TWENTY GOOD REASONSNot to worry about polar bears an update

Susan J Crockford

The Global Warming Policy Foundation

GWPF Briefing 28

GWPF REPORTSViews expressed in the publications ofthe Global Warming Policy Foundationare those of the authors not those ofthe GWPF its Academic Advisory Coun-cil members or its directors

THE GLOBALWARMING POLICY FOUNDATIONDirectorBenny Peiser

BOARDOF TRUSTEESLord Lawson (Chairman) Peter LilleyLord Donoughue Charles MooreLord Fellowes Baroness NicholsonRt RevdDrPeter Forster BishopofChester Graham Stringer MPSir Martin Jacomb Lord Turnbull

ACADEMIC ADVISORY COUNCILProfessor Christopher Essex (Chairman) Professor Ross McKitrickSir Samuel Brittan Professor Garth PaltridgeSir Ian Byatt Professor Ian PlimerDr John Constable Professor Paul ReiterProfessor Vincent Courtillot Dr Matt RidleyProfessor Freeman Dyson Sir Alan RudgeChristian Gerondeau Professor Nir ShavivProfessor William Happer Professor Philip StottProfessor David Henderson Professor Henrik SvensmarkProfessor Terence Kealey Professor Anastasios TsonisProfessor Deepak Lal Professor Fritz VahrenholtProfessor Richard Lindzen Dr David WhitehouseProfessor Robert Mendelsohn

CREDITSCover image Copyright Cartoons by Joshwwwcartoonsbyjoshcom

TWENTY GOOD REASONSNot to worry about polar bears an update

Susan J Crockford

copy Copyright 2017 The Global Warming Policy Foundation

Contents

About the author vii

Executive summary ix

Introduction 1

1 A conservation success story 1

2 Fewer populations in decline 1

3 Abrupt summer sea icedeclinehasnot affectedpolar bearnumbersas predicted 4

4 Chukchi Sea population is thriving 5

5 More prey means healthier polar bears 5

6 Polar bears are adaptable 6

7 Southern Beaufort numbers have rebounded 6

8 Barents Sea numbers have increased 6

9 Low sea ice in 2012 had no harmful effect on Southern Beaufortbear numbers 7

10 Other species impacted by high polar bear numbers 7

11 Western Hudson Bay population numbers are stable 7

12 Hudson Bay sea ice is not changing much 10

13 Problem bears in Churchill are not lean or starving 10

14 Churchill Manitoba had the most problem bears in 1983 and 2016 10

15 Marginal sea ice declines during the feeding period 11

16 No evidence that subsistence hunting is affecting bear populations 12

17 Stressful research methods have been curtailed 12

18 No recent reports of polar bear cannibalism 13

v

19 Polar bears appear unaffected by pollution 14

20 Polar bears have survived past warm periods 14

Conclusion 14

Notes 16

About the authorDr Susan Crockford is an evolutionary biologist and has been working for 35 yearsin archaeozoology paleozoology and forensic zoology She is an adjunct professor attheUniversity of Victoria British Columbia butworks full time for a private consultingcompany she co-owns (Pacific Identifications Inc) She is the author of Rhythms ofLife Thyroid Hormone and the Origin of Species Eaten A Novel (a polar bear attackthriller) Polar Bear Facts and Myths (for ages seven and up also available in Frenchand German) Polar Bears Have Big Feet (for preschoolers) and the fully referencedPolar Bears Outstanding Survivors of Climate Change1 as well as a scientific paper onpolar bear conservation status2 She has authored several earlier briefing papers andvideos for GWPF on the subjects of polar bears and walrus345678 Susan Crockfordblogs at wwwpolarbearsciencecom

vii

Executive summary1 Polar bears are still a conservation success story there are more polar bears

now than there were 40 years ago

2 Fewer populations are in decline than in 2010 (only one officially) and only sixare data deficient (down from nine)

3 Abrupt summer sea ice decline has not affected polar bear numbers as pre-dicted even though sea ice levels dropped to mid-century levels in 2007 theexpected decimation of polar bears failed to occur

4 The Chukchi Sea population is thriving despite a pronounced lengthening ofthe ice-free season since 2007

5 Less sea ice in the summer in the Chukchi Sea has meant a healthy prey basefor polar bears because ringed seals feed primarily in the ice-free season

6 Polar bears have shown themselves to be adaptable to changing ice conditionsin several regions

7 Southern Beaufort numbers have rebounded since the last survey count

8 Barents Sea numbers have probably increased since 2005 and have definitelynot declined despite much less sea ice cover

9 There is no evidence that record-low summer sea ice in 2012 had a harmfuleffect on Southern Beaufort bear numbers

10 Other species are being negatively impacted by high polar bear numbers es-pecially nesting sea birds and ducks

11 Western Hudson Bay population numbers have been stable since 2004 despitewhat scientists are telling the media

12 Hudson Bay sea ice has not changed since about 1999 the breakup dates andfreeze-up dates are highly variable but the ice-free period was not any longerin 2015 than it was in 2004 However this fall freeze-up is shaping up to be theearliest in decades

13 Problem bears in Churchill are not lean or starving

14 Churchill Manitoba had the most problem bears in 1983 and 2016 which werelate freeze-up years but many of the incidents in 2016 can be attributed to in-creased vigilance on the part of patrol officers after an attack in 2013

15 There have been only marginal sea-ice declines during the feeding period inspring when polar bears need sea ice the most

16 The is no evidence that subsistence hunting is affecting bear populations

17 Stressful research methods have been curtailed in much of Canada

ix

18 There have been no reports of polar bear cannibalism since 2011

19 Polar bears appear unaffected by pollution studies suggest only that harm istheoretically possible not that it has happened

20 Polar bears have survived past warm periods which is evidence they have theability to survive future warm periods

Conclusion

bull Polar bears are thriving they are not currently threatened with extinction

bull Tens of thousands of polar bears did not die as a result of more than a decadeof low summer sea ice as was predicted

bull Polar bears donrsquot need sea ice in late summerearly fall as long as they are well-fed in the spring

x

IntroductionJust in time for Polar Bears Internationalrsquos self-proclaimed9 fall Polar Bear Week (5ndash11November 2017)10 here is a new resource for cooling the polar bear spin Irsquove up-dated my 2015 summary of reasons not to worry about polar bears which is nowmore than two years old11 In this new version you will find links to supporting in-formation including published papers and fully referenced blog posts of mine thatprovide backgroundmaps andbibliographies although someof themost importantgraphs andmaps have been reproduced here I hope you find it a useful resource forrefuting the pessimism1213 and prophecies of catastrophe14 about the future of po-lar bears Please feel free to share it As global leaders meet in Bonn for COP23 (6ndash17November 2017)15 itrsquos time to celebrate the proven resilience of polar bears to theirever-changing Arctic environment

1 A conservation success storyPolar bears are still a conservation success story16 With the estimated global popu-lation almost certainly greater than 2800017 we can say for sure that there are morepolarbearsnowthan therewere40years ago (Figure1)18 Sadly althoughcompletinga global survey was one of the primary objectives of the Polar Bear Specialist Group(PBSG) at its inception 49 years ago it has so far been unable to do so because at leastfour subpopulations have never been counted The PBSG global estimate was listedin July 2014 as lsquoapproximately 25000rsquo bears19 This number has not been revised20

even though the estimate PBSG members provided the International Union for theConservation of Nature (IUCN) for its 2015 assessment was 22000ndash31000 or about2600021 Surveys completed or published since bring the total higher still2

Even with the lack of precision inherent in these estimates global numbers arestill too high to qualify the polar bear as lsquovulnerablersquo to or lsquothreatenedrsquo with extinc-tion based on current population levels22 Polar bears today are also well distributedthroughout their available habitat (winter sea ice)23 which is a recognized charac-teristic of a healthy species All concerns expressed regarding polar bear survival areabout the future24

2 Fewer populations in declineA recent status assessment for polar bears published by Environment Canada inMay201426 showed only two subpopulations are lsquolikely decliningrsquo down from four listedby the PBSG as declining in 2013 and seven in 2010 (Figure 2)27 Baffin Bay whichearned its lsquolikely decliningrsquo status due to suspicions of overharvesting (not sea ice de-cline) was reported in 2017 to be likely stable28 Kane Basin assessed as lsquodecliningrsquoin 2010 and 2013 (but lsquodata deficientrsquo in 2014) was reported in 2017 to be lsquostablersquo or

1

0

5

10

15

20

25

30

0

5

10

15

20

25

30

1950 1960 1970 1980 1990 2000 2010

1950 1960 1970 1980 1990 2000 2010

(a) Official estimate

(b) Unofficial estimate

Figure 1 Official estimates of polar bear numbersUpper graph uses totals reported in PBSG status tables (to 2013) with minmax lowergraph uses the same figures but adds back in the so-called lsquoinaccuratersquo estimates

dropped between 2005 and 2013 (in 2014 the PBSG finally did the same)25 The 1960figure is a ballpark estimate Further detail can be found at my website18 and Crockford

20172

2

lsquolikely increasingrsquo28 (but see Section 10) This leaves only the Southern Beaufort bearpopulation as lsquolikely decliningrsquo and even this is a highly questionable assessment (seeSection 7) Note also that the number of subpopulation considered lsquodata deficientrsquo(Figure 2 areas in brown) has been reduced from nine in 2014 to six in 2017 threebear populations (Barents Sea Kara Sea and Kane Basin) have recently been surveyedand now have population estimates showing probable increases

For example a first-ever Kara Sea population estimate completed in late 2014potentially adds another 3200 or so bears to the global total29 This estimate (range2700ndash3500) derivedbyRussianbiologists was added to theofficial global countpub-lished in 2015 by the IUCN Red List21 A former ball-park estimate was about 200018

suggesting an increase may have taken place

Figure 2 Global polar bear population status assessment even better than thisFigures from the IUCN Polar Bear Specialist Group assessment (2013) and EnvironmentCanada (May 2014)30 Brown data deficient red declining yellow likely decline lightblue likely stable dark blue stable light green likely increase dark green increase

More recent surveys show BB BS KB and KS are stable or likely increasing2

3

3 Abrupt summer sea ice decline has not affectedpolar bear numbers as predicted

Arctic sea ice has declined since satellite records began in 1979 but polar bears haveso far adjusted well to this change especially to the sudden decline to reduced sum-mer sea ice levels that have been the norm since 2007 The degree of abrupt dropin summer sea ice that occurred in 2007 was not predicted by experts to occur untilmid-century However the predicted decimation of polar bears worldwide expectedunder mid-century conditions (Figure 3)31 ndash which entailed a loss of 23 of the globaltotal (to only about 6660ndash8325 bears) as well as the total extermination of 10 entiresubpopulations ndash not only failed to occur it did not come even close to happening32

If the experts had been right back in 2007 there would be no polar bears at all inthe Southern Beaufort or Western Hudson Bay this year33 There is also evidence thatless summer ice in the Central Canadian Arctic has already been beneficial for polarbears34 an advantage not expected until later this century This is due in part to thefact that less summer ice is good for ringed seals - on which polar bears prey ndash whichfeed primarily during the ice-free season (see Section 5) and which do best with first-year ice cover during the spring birthing and mating seasons

(a) (b)

Figure 3 Predicted sea ice changes versus outturn(a) Predictions based on 2004 data for 2020 (light grey) 2050 (mid grey) and 2080(dark grey) These were used in 2007 to predict a 66 decline in global polar bearnumbers (b) Situation as at 10 September 2012 an example of the sea ice extent

experienced in since 200735 See Crockford 2017 for details2

4

4 Chukchi Sea population is thrivingThe results of a new study published in 2013 were a direct contradiction of the re-peatedmessage that recent large sea-ice declines in late summer hadput these bearsin peril36 The paper showed that Chukchi polar bears are doingbetter than theywerein the 1980s37 and better than any others except the bears of Foxe Basin (northernHudson Bay) who are doing exceptionally well38

There is still no official population estimate for the Chukchi Sea the population isofficially listed as zero but was previously estimated at about 2000 individuals How-ever it appears that record-breaking sea-ice levels in September 2007 the lowestsince 1979 had no discernible effect on Chukchi Sea polar bears39 as confirmed byresearch up to 2016240 As a result the status of this population was upgraded fromlsquodecliningrsquo to lsquodata deficientrsquo by the PBSG in 201341 Despite the gloomy predictions alonger-than-average ice-freeperiodhas actually beengood forChukchi polar bears42

5 More preymeans healthier polar bearsThe reason Chukchi Sea polar bears did so well with an extended open-water sea-son was because ringed seals their primary prey do most of their feeding in ice-freesummer waters More fat seals mean more fat seal pups the following spring for po-lar bears A recent study found that in recent years with extensive September sea-iceminimums the summer feedingperiod for sealswas extendedand theybecameextrafat43 This meant that some seals provided a more energy-rich food source for polarbears over the following fall and winter an immediate benefit to the bears In addi-tion well-fed female ringed seals produced fat healthy pups the next spring whichmeant more food for polar bears when they needed it the most

Between 2008 and 2011 both ringed seals and polar bears did better than eitherhad done in the 1980s when summer sea ice coverage was more extensive Oddlyin March 2013 less than six months after ringed seals were placed on the Americanlist of species lsquothreatenedrsquo with extinction44 ringed seal biologists were reporting totheir peers that the results of their Chukchi Sea research contradicted their dire pre-dictions45 Surprisingly to them less summer sea ice was better for ringed seals notworse In July 2014 a judge decreed that the 2012 decision to list bearded seals inAlaska as lsquothreatenedrsquo was deficient and that there were no near-term threats Thejudge called it lsquoan abuse of discretionrsquo46

The USA stands out as the only nation that insists that Arctic seals have been (orwill be shortly) harmed by recent declines in summer sea ice47 which made it all themore surprising that in September 2017 the US Fish andWildlife Service announcedit would not pursue a plan to list Pacific walrus as lsquothreatenedrsquo with extinction underthe Endangered Species Act48 Their experts concluded there was no evidence of on-going harm or an imminent threat to walrus survival

5

6 Polar bears are adaptablePolar bears have been shown to move from areas with unsuitable ice to areas withbetter ice conditions even over the short term This is strong evidence of their abilityto adapt to changing sea ice Recently it was noted that a number of bears from theBarents Seawhere sea-ice coverage is strongly influencedbyvariations in theAtlanticMultidecadal Oscillation49 moved to the islands of the Franz Josef Land archipelagoin the Kara Sea where there has beenmore predictable ice cover50 This is just one ex-ample of polar bear flexibility A past example was the movement of Southern Beau-fort bears into the Chukchi Sea during the catastrophic 1974ndash1976 episode of thickspring ice in the Eastern Beaufort Flexibility in choosing maternity dens (onshorevs sea ice) as well as variability in feeding areas (nearshore vs offshore)51 give polarbears the resilience they need to survive as a species

7 Southern Beaufort numbers have reboundedAccording to a preliminary US Fish amp Wildlife Service survey Southern Beaufort bearnumberswerehigher in the fall of 2012 than theyhadbeen in theprevious tenyears52

indicating a recovery from the dramatic decline (25ndash50) that occurred between2004 and 2006 because of the effects of thick spring sea ice53 For unknown rea-sons the newly-developed models used to estimate Southern Beaufort populationsize used only data up until 2010 even though mark-recapture data up until 2012were available54 This is known because the data was used for another study seeSection 8 The failure of thick spring ice conditions to recur in recent years and theearly formation and expansion of spring polynyas in the eastern Beaufort have likelybeenbeneficial for polar bears and seals55 resulting in the rare sighting of at least oneset of healthy triplet cubs in 201656

8 Barents Sea numbers have increasedThe Svalbard portion of the Barents Sea subpopulation was surveyed in 2015 andwas initially reported to have increased by 42 over the count performed in 200457

The just-publishedpaper confirms that a 42 increase in abundance indeedoccurred(685 bears in 2004 versus 973 bears in 2015)58 However due to the large uncertainty(broad error ranges) in the estimates involved even a 42 increase was not statis-tically significant This point was strongly emphasized by the PBSG59 in their recentstatus update for the Barents Sea

Becauseof theoverlapping confidence intervals it cannot be concluded that theBS subpopulation has grown60

The authors of the Svalbard survey however had this to say

6

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

GWPF REPORTSViews expressed in the publications ofthe Global Warming Policy Foundationare those of the authors not those ofthe GWPF its Academic Advisory Coun-cil members or its directors

THE GLOBALWARMING POLICY FOUNDATIONDirectorBenny Peiser

BOARDOF TRUSTEESLord Lawson (Chairman) Peter LilleyLord Donoughue Charles MooreLord Fellowes Baroness NicholsonRt RevdDrPeter Forster BishopofChester Graham Stringer MPSir Martin Jacomb Lord Turnbull

ACADEMIC ADVISORY COUNCILProfessor Christopher Essex (Chairman) Professor Ross McKitrickSir Samuel Brittan Professor Garth PaltridgeSir Ian Byatt Professor Ian PlimerDr John Constable Professor Paul ReiterProfessor Vincent Courtillot Dr Matt RidleyProfessor Freeman Dyson Sir Alan RudgeChristian Gerondeau Professor Nir ShavivProfessor William Happer Professor Philip StottProfessor David Henderson Professor Henrik SvensmarkProfessor Terence Kealey Professor Anastasios TsonisProfessor Deepak Lal Professor Fritz VahrenholtProfessor Richard Lindzen Dr David WhitehouseProfessor Robert Mendelsohn

CREDITSCover image Copyright Cartoons by Joshwwwcartoonsbyjoshcom

TWENTY GOOD REASONSNot to worry about polar bears an update

Susan J Crockford

copy Copyright 2017 The Global Warming Policy Foundation

Contents

About the author vii

Executive summary ix

Introduction 1

1 A conservation success story 1

2 Fewer populations in decline 1

3 Abrupt summer sea icedeclinehasnot affectedpolar bearnumbersas predicted 4

4 Chukchi Sea population is thriving 5

5 More prey means healthier polar bears 5

6 Polar bears are adaptable 6

7 Southern Beaufort numbers have rebounded 6

8 Barents Sea numbers have increased 6

9 Low sea ice in 2012 had no harmful effect on Southern Beaufortbear numbers 7

10 Other species impacted by high polar bear numbers 7

11 Western Hudson Bay population numbers are stable 7

12 Hudson Bay sea ice is not changing much 10

13 Problem bears in Churchill are not lean or starving 10

14 Churchill Manitoba had the most problem bears in 1983 and 2016 10

15 Marginal sea ice declines during the feeding period 11

16 No evidence that subsistence hunting is affecting bear populations 12

17 Stressful research methods have been curtailed 12

18 No recent reports of polar bear cannibalism 13

v

19 Polar bears appear unaffected by pollution 14

20 Polar bears have survived past warm periods 14

Conclusion 14

Notes 16

About the authorDr Susan Crockford is an evolutionary biologist and has been working for 35 yearsin archaeozoology paleozoology and forensic zoology She is an adjunct professor attheUniversity of Victoria British Columbia butworks full time for a private consultingcompany she co-owns (Pacific Identifications Inc) She is the author of Rhythms ofLife Thyroid Hormone and the Origin of Species Eaten A Novel (a polar bear attackthriller) Polar Bear Facts and Myths (for ages seven and up also available in Frenchand German) Polar Bears Have Big Feet (for preschoolers) and the fully referencedPolar Bears Outstanding Survivors of Climate Change1 as well as a scientific paper onpolar bear conservation status2 She has authored several earlier briefing papers andvideos for GWPF on the subjects of polar bears and walrus345678 Susan Crockfordblogs at wwwpolarbearsciencecom

vii

Executive summary1 Polar bears are still a conservation success story there are more polar bears

now than there were 40 years ago

2 Fewer populations are in decline than in 2010 (only one officially) and only sixare data deficient (down from nine)

3 Abrupt summer sea ice decline has not affected polar bear numbers as pre-dicted even though sea ice levels dropped to mid-century levels in 2007 theexpected decimation of polar bears failed to occur

4 The Chukchi Sea population is thriving despite a pronounced lengthening ofthe ice-free season since 2007

5 Less sea ice in the summer in the Chukchi Sea has meant a healthy prey basefor polar bears because ringed seals feed primarily in the ice-free season

6 Polar bears have shown themselves to be adaptable to changing ice conditionsin several regions

7 Southern Beaufort numbers have rebounded since the last survey count

8 Barents Sea numbers have probably increased since 2005 and have definitelynot declined despite much less sea ice cover

9 There is no evidence that record-low summer sea ice in 2012 had a harmfuleffect on Southern Beaufort bear numbers

10 Other species are being negatively impacted by high polar bear numbers es-pecially nesting sea birds and ducks

11 Western Hudson Bay population numbers have been stable since 2004 despitewhat scientists are telling the media

12 Hudson Bay sea ice has not changed since about 1999 the breakup dates andfreeze-up dates are highly variable but the ice-free period was not any longerin 2015 than it was in 2004 However this fall freeze-up is shaping up to be theearliest in decades

13 Problem bears in Churchill are not lean or starving

14 Churchill Manitoba had the most problem bears in 1983 and 2016 which werelate freeze-up years but many of the incidents in 2016 can be attributed to in-creased vigilance on the part of patrol officers after an attack in 2013

15 There have been only marginal sea-ice declines during the feeding period inspring when polar bears need sea ice the most

16 The is no evidence that subsistence hunting is affecting bear populations

17 Stressful research methods have been curtailed in much of Canada

ix

18 There have been no reports of polar bear cannibalism since 2011

19 Polar bears appear unaffected by pollution studies suggest only that harm istheoretically possible not that it has happened

20 Polar bears have survived past warm periods which is evidence they have theability to survive future warm periods

Conclusion

bull Polar bears are thriving they are not currently threatened with extinction

bull Tens of thousands of polar bears did not die as a result of more than a decadeof low summer sea ice as was predicted

bull Polar bears donrsquot need sea ice in late summerearly fall as long as they are well-fed in the spring

x

IntroductionJust in time for Polar Bears Internationalrsquos self-proclaimed9 fall Polar Bear Week (5ndash11November 2017)10 here is a new resource for cooling the polar bear spin Irsquove up-dated my 2015 summary of reasons not to worry about polar bears which is nowmore than two years old11 In this new version you will find links to supporting in-formation including published papers and fully referenced blog posts of mine thatprovide backgroundmaps andbibliographies although someof themost importantgraphs andmaps have been reproduced here I hope you find it a useful resource forrefuting the pessimism1213 and prophecies of catastrophe14 about the future of po-lar bears Please feel free to share it As global leaders meet in Bonn for COP23 (6ndash17November 2017)15 itrsquos time to celebrate the proven resilience of polar bears to theirever-changing Arctic environment

1 A conservation success storyPolar bears are still a conservation success story16 With the estimated global popu-lation almost certainly greater than 2800017 we can say for sure that there are morepolarbearsnowthan therewere40years ago (Figure1)18 Sadly althoughcompletinga global survey was one of the primary objectives of the Polar Bear Specialist Group(PBSG) at its inception 49 years ago it has so far been unable to do so because at leastfour subpopulations have never been counted The PBSG global estimate was listedin July 2014 as lsquoapproximately 25000rsquo bears19 This number has not been revised20

even though the estimate PBSG members provided the International Union for theConservation of Nature (IUCN) for its 2015 assessment was 22000ndash31000 or about2600021 Surveys completed or published since bring the total higher still2

Even with the lack of precision inherent in these estimates global numbers arestill too high to qualify the polar bear as lsquovulnerablersquo to or lsquothreatenedrsquo with extinc-tion based on current population levels22 Polar bears today are also well distributedthroughout their available habitat (winter sea ice)23 which is a recognized charac-teristic of a healthy species All concerns expressed regarding polar bear survival areabout the future24

2 Fewer populations in declineA recent status assessment for polar bears published by Environment Canada inMay201426 showed only two subpopulations are lsquolikely decliningrsquo down from four listedby the PBSG as declining in 2013 and seven in 2010 (Figure 2)27 Baffin Bay whichearned its lsquolikely decliningrsquo status due to suspicions of overharvesting (not sea ice de-cline) was reported in 2017 to be likely stable28 Kane Basin assessed as lsquodecliningrsquoin 2010 and 2013 (but lsquodata deficientrsquo in 2014) was reported in 2017 to be lsquostablersquo or

1

0

5

10

15

20

25

30

0

5

10

15

20

25

30

1950 1960 1970 1980 1990 2000 2010

1950 1960 1970 1980 1990 2000 2010

(a) Official estimate

(b) Unofficial estimate

Figure 1 Official estimates of polar bear numbersUpper graph uses totals reported in PBSG status tables (to 2013) with minmax lowergraph uses the same figures but adds back in the so-called lsquoinaccuratersquo estimates

dropped between 2005 and 2013 (in 2014 the PBSG finally did the same)25 The 1960figure is a ballpark estimate Further detail can be found at my website18 and Crockford

20172

2

lsquolikely increasingrsquo28 (but see Section 10) This leaves only the Southern Beaufort bearpopulation as lsquolikely decliningrsquo and even this is a highly questionable assessment (seeSection 7) Note also that the number of subpopulation considered lsquodata deficientrsquo(Figure 2 areas in brown) has been reduced from nine in 2014 to six in 2017 threebear populations (Barents Sea Kara Sea and Kane Basin) have recently been surveyedand now have population estimates showing probable increases

For example a first-ever Kara Sea population estimate completed in late 2014potentially adds another 3200 or so bears to the global total29 This estimate (range2700ndash3500) derivedbyRussianbiologists was added to theofficial global countpub-lished in 2015 by the IUCN Red List21 A former ball-park estimate was about 200018

suggesting an increase may have taken place

Figure 2 Global polar bear population status assessment even better than thisFigures from the IUCN Polar Bear Specialist Group assessment (2013) and EnvironmentCanada (May 2014)30 Brown data deficient red declining yellow likely decline lightblue likely stable dark blue stable light green likely increase dark green increase

More recent surveys show BB BS KB and KS are stable or likely increasing2

3

3 Abrupt summer sea ice decline has not affectedpolar bear numbers as predicted

Arctic sea ice has declined since satellite records began in 1979 but polar bears haveso far adjusted well to this change especially to the sudden decline to reduced sum-mer sea ice levels that have been the norm since 2007 The degree of abrupt dropin summer sea ice that occurred in 2007 was not predicted by experts to occur untilmid-century However the predicted decimation of polar bears worldwide expectedunder mid-century conditions (Figure 3)31 ndash which entailed a loss of 23 of the globaltotal (to only about 6660ndash8325 bears) as well as the total extermination of 10 entiresubpopulations ndash not only failed to occur it did not come even close to happening32

If the experts had been right back in 2007 there would be no polar bears at all inthe Southern Beaufort or Western Hudson Bay this year33 There is also evidence thatless summer ice in the Central Canadian Arctic has already been beneficial for polarbears34 an advantage not expected until later this century This is due in part to thefact that less summer ice is good for ringed seals - on which polar bears prey ndash whichfeed primarily during the ice-free season (see Section 5) and which do best with first-year ice cover during the spring birthing and mating seasons

(a) (b)

Figure 3 Predicted sea ice changes versus outturn(a) Predictions based on 2004 data for 2020 (light grey) 2050 (mid grey) and 2080(dark grey) These were used in 2007 to predict a 66 decline in global polar bearnumbers (b) Situation as at 10 September 2012 an example of the sea ice extent

experienced in since 200735 See Crockford 2017 for details2

4

4 Chukchi Sea population is thrivingThe results of a new study published in 2013 were a direct contradiction of the re-peatedmessage that recent large sea-ice declines in late summer hadput these bearsin peril36 The paper showed that Chukchi polar bears are doingbetter than theywerein the 1980s37 and better than any others except the bears of Foxe Basin (northernHudson Bay) who are doing exceptionally well38

There is still no official population estimate for the Chukchi Sea the population isofficially listed as zero but was previously estimated at about 2000 individuals How-ever it appears that record-breaking sea-ice levels in September 2007 the lowestsince 1979 had no discernible effect on Chukchi Sea polar bears39 as confirmed byresearch up to 2016240 As a result the status of this population was upgraded fromlsquodecliningrsquo to lsquodata deficientrsquo by the PBSG in 201341 Despite the gloomy predictions alonger-than-average ice-freeperiodhas actually beengood forChukchi polar bears42

5 More preymeans healthier polar bearsThe reason Chukchi Sea polar bears did so well with an extended open-water sea-son was because ringed seals their primary prey do most of their feeding in ice-freesummer waters More fat seals mean more fat seal pups the following spring for po-lar bears A recent study found that in recent years with extensive September sea-iceminimums the summer feedingperiod for sealswas extendedand theybecameextrafat43 This meant that some seals provided a more energy-rich food source for polarbears over the following fall and winter an immediate benefit to the bears In addi-tion well-fed female ringed seals produced fat healthy pups the next spring whichmeant more food for polar bears when they needed it the most

Between 2008 and 2011 both ringed seals and polar bears did better than eitherhad done in the 1980s when summer sea ice coverage was more extensive Oddlyin March 2013 less than six months after ringed seals were placed on the Americanlist of species lsquothreatenedrsquo with extinction44 ringed seal biologists were reporting totheir peers that the results of their Chukchi Sea research contradicted their dire pre-dictions45 Surprisingly to them less summer sea ice was better for ringed seals notworse In July 2014 a judge decreed that the 2012 decision to list bearded seals inAlaska as lsquothreatenedrsquo was deficient and that there were no near-term threats Thejudge called it lsquoan abuse of discretionrsquo46

The USA stands out as the only nation that insists that Arctic seals have been (orwill be shortly) harmed by recent declines in summer sea ice47 which made it all themore surprising that in September 2017 the US Fish andWildlife Service announcedit would not pursue a plan to list Pacific walrus as lsquothreatenedrsquo with extinction underthe Endangered Species Act48 Their experts concluded there was no evidence of on-going harm or an imminent threat to walrus survival

5

6 Polar bears are adaptablePolar bears have been shown to move from areas with unsuitable ice to areas withbetter ice conditions even over the short term This is strong evidence of their abilityto adapt to changing sea ice Recently it was noted that a number of bears from theBarents Seawhere sea-ice coverage is strongly influencedbyvariations in theAtlanticMultidecadal Oscillation49 moved to the islands of the Franz Josef Land archipelagoin the Kara Sea where there has beenmore predictable ice cover50 This is just one ex-ample of polar bear flexibility A past example was the movement of Southern Beau-fort bears into the Chukchi Sea during the catastrophic 1974ndash1976 episode of thickspring ice in the Eastern Beaufort Flexibility in choosing maternity dens (onshorevs sea ice) as well as variability in feeding areas (nearshore vs offshore)51 give polarbears the resilience they need to survive as a species

7 Southern Beaufort numbers have reboundedAccording to a preliminary US Fish amp Wildlife Service survey Southern Beaufort bearnumberswerehigher in the fall of 2012 than theyhadbeen in theprevious tenyears52

indicating a recovery from the dramatic decline (25ndash50) that occurred between2004 and 2006 because of the effects of thick spring sea ice53 For unknown rea-sons the newly-developed models used to estimate Southern Beaufort populationsize used only data up until 2010 even though mark-recapture data up until 2012were available54 This is known because the data was used for another study seeSection 8 The failure of thick spring ice conditions to recur in recent years and theearly formation and expansion of spring polynyas in the eastern Beaufort have likelybeenbeneficial for polar bears and seals55 resulting in the rare sighting of at least oneset of healthy triplet cubs in 201656

8 Barents Sea numbers have increasedThe Svalbard portion of the Barents Sea subpopulation was surveyed in 2015 andwas initially reported to have increased by 42 over the count performed in 200457

The just-publishedpaper confirms that a 42 increase in abundance indeedoccurred(685 bears in 2004 versus 973 bears in 2015)58 However due to the large uncertainty(broad error ranges) in the estimates involved even a 42 increase was not statis-tically significant This point was strongly emphasized by the PBSG59 in their recentstatus update for the Barents Sea

Becauseof theoverlapping confidence intervals it cannot be concluded that theBS subpopulation has grown60

The authors of the Svalbard survey however had this to say

6

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

TWENTY GOOD REASONSNot to worry about polar bears an update

Susan J Crockford

copy Copyright 2017 The Global Warming Policy Foundation

Contents

About the author vii

Executive summary ix

Introduction 1

1 A conservation success story 1

2 Fewer populations in decline 1

3 Abrupt summer sea icedeclinehasnot affectedpolar bearnumbersas predicted 4

4 Chukchi Sea population is thriving 5

5 More prey means healthier polar bears 5

6 Polar bears are adaptable 6

7 Southern Beaufort numbers have rebounded 6

8 Barents Sea numbers have increased 6

9 Low sea ice in 2012 had no harmful effect on Southern Beaufortbear numbers 7

10 Other species impacted by high polar bear numbers 7

11 Western Hudson Bay population numbers are stable 7

12 Hudson Bay sea ice is not changing much 10

13 Problem bears in Churchill are not lean or starving 10

14 Churchill Manitoba had the most problem bears in 1983 and 2016 10

15 Marginal sea ice declines during the feeding period 11

16 No evidence that subsistence hunting is affecting bear populations 12

17 Stressful research methods have been curtailed 12

18 No recent reports of polar bear cannibalism 13

v

19 Polar bears appear unaffected by pollution 14

20 Polar bears have survived past warm periods 14

Conclusion 14

Notes 16

About the authorDr Susan Crockford is an evolutionary biologist and has been working for 35 yearsin archaeozoology paleozoology and forensic zoology She is an adjunct professor attheUniversity of Victoria British Columbia butworks full time for a private consultingcompany she co-owns (Pacific Identifications Inc) She is the author of Rhythms ofLife Thyroid Hormone and the Origin of Species Eaten A Novel (a polar bear attackthriller) Polar Bear Facts and Myths (for ages seven and up also available in Frenchand German) Polar Bears Have Big Feet (for preschoolers) and the fully referencedPolar Bears Outstanding Survivors of Climate Change1 as well as a scientific paper onpolar bear conservation status2 She has authored several earlier briefing papers andvideos for GWPF on the subjects of polar bears and walrus345678 Susan Crockfordblogs at wwwpolarbearsciencecom

vii

Executive summary1 Polar bears are still a conservation success story there are more polar bears

now than there were 40 years ago

2 Fewer populations are in decline than in 2010 (only one officially) and only sixare data deficient (down from nine)

3 Abrupt summer sea ice decline has not affected polar bear numbers as pre-dicted even though sea ice levels dropped to mid-century levels in 2007 theexpected decimation of polar bears failed to occur

4 The Chukchi Sea population is thriving despite a pronounced lengthening ofthe ice-free season since 2007

5 Less sea ice in the summer in the Chukchi Sea has meant a healthy prey basefor polar bears because ringed seals feed primarily in the ice-free season

6 Polar bears have shown themselves to be adaptable to changing ice conditionsin several regions

7 Southern Beaufort numbers have rebounded since the last survey count

8 Barents Sea numbers have probably increased since 2005 and have definitelynot declined despite much less sea ice cover

9 There is no evidence that record-low summer sea ice in 2012 had a harmfuleffect on Southern Beaufort bear numbers

10 Other species are being negatively impacted by high polar bear numbers es-pecially nesting sea birds and ducks

11 Western Hudson Bay population numbers have been stable since 2004 despitewhat scientists are telling the media

12 Hudson Bay sea ice has not changed since about 1999 the breakup dates andfreeze-up dates are highly variable but the ice-free period was not any longerin 2015 than it was in 2004 However this fall freeze-up is shaping up to be theearliest in decades

13 Problem bears in Churchill are not lean or starving

14 Churchill Manitoba had the most problem bears in 1983 and 2016 which werelate freeze-up years but many of the incidents in 2016 can be attributed to in-creased vigilance on the part of patrol officers after an attack in 2013

15 There have been only marginal sea-ice declines during the feeding period inspring when polar bears need sea ice the most

16 The is no evidence that subsistence hunting is affecting bear populations

17 Stressful research methods have been curtailed in much of Canada

ix

18 There have been no reports of polar bear cannibalism since 2011

19 Polar bears appear unaffected by pollution studies suggest only that harm istheoretically possible not that it has happened

20 Polar bears have survived past warm periods which is evidence they have theability to survive future warm periods

Conclusion

bull Polar bears are thriving they are not currently threatened with extinction

bull Tens of thousands of polar bears did not die as a result of more than a decadeof low summer sea ice as was predicted

bull Polar bears donrsquot need sea ice in late summerearly fall as long as they are well-fed in the spring

x

IntroductionJust in time for Polar Bears Internationalrsquos self-proclaimed9 fall Polar Bear Week (5ndash11November 2017)10 here is a new resource for cooling the polar bear spin Irsquove up-dated my 2015 summary of reasons not to worry about polar bears which is nowmore than two years old11 In this new version you will find links to supporting in-formation including published papers and fully referenced blog posts of mine thatprovide backgroundmaps andbibliographies although someof themost importantgraphs andmaps have been reproduced here I hope you find it a useful resource forrefuting the pessimism1213 and prophecies of catastrophe14 about the future of po-lar bears Please feel free to share it As global leaders meet in Bonn for COP23 (6ndash17November 2017)15 itrsquos time to celebrate the proven resilience of polar bears to theirever-changing Arctic environment

1 A conservation success storyPolar bears are still a conservation success story16 With the estimated global popu-lation almost certainly greater than 2800017 we can say for sure that there are morepolarbearsnowthan therewere40years ago (Figure1)18 Sadly althoughcompletinga global survey was one of the primary objectives of the Polar Bear Specialist Group(PBSG) at its inception 49 years ago it has so far been unable to do so because at leastfour subpopulations have never been counted The PBSG global estimate was listedin July 2014 as lsquoapproximately 25000rsquo bears19 This number has not been revised20

even though the estimate PBSG members provided the International Union for theConservation of Nature (IUCN) for its 2015 assessment was 22000ndash31000 or about2600021 Surveys completed or published since bring the total higher still2

Even with the lack of precision inherent in these estimates global numbers arestill too high to qualify the polar bear as lsquovulnerablersquo to or lsquothreatenedrsquo with extinc-tion based on current population levels22 Polar bears today are also well distributedthroughout their available habitat (winter sea ice)23 which is a recognized charac-teristic of a healthy species All concerns expressed regarding polar bear survival areabout the future24

2 Fewer populations in declineA recent status assessment for polar bears published by Environment Canada inMay201426 showed only two subpopulations are lsquolikely decliningrsquo down from four listedby the PBSG as declining in 2013 and seven in 2010 (Figure 2)27 Baffin Bay whichearned its lsquolikely decliningrsquo status due to suspicions of overharvesting (not sea ice de-cline) was reported in 2017 to be likely stable28 Kane Basin assessed as lsquodecliningrsquoin 2010 and 2013 (but lsquodata deficientrsquo in 2014) was reported in 2017 to be lsquostablersquo or

1

0

5

10

15

20

25

30

0

5

10

15

20

25

30

1950 1960 1970 1980 1990 2000 2010

1950 1960 1970 1980 1990 2000 2010

(a) Official estimate

(b) Unofficial estimate

Figure 1 Official estimates of polar bear numbersUpper graph uses totals reported in PBSG status tables (to 2013) with minmax lowergraph uses the same figures but adds back in the so-called lsquoinaccuratersquo estimates

dropped between 2005 and 2013 (in 2014 the PBSG finally did the same)25 The 1960figure is a ballpark estimate Further detail can be found at my website18 and Crockford

20172

2

lsquolikely increasingrsquo28 (but see Section 10) This leaves only the Southern Beaufort bearpopulation as lsquolikely decliningrsquo and even this is a highly questionable assessment (seeSection 7) Note also that the number of subpopulation considered lsquodata deficientrsquo(Figure 2 areas in brown) has been reduced from nine in 2014 to six in 2017 threebear populations (Barents Sea Kara Sea and Kane Basin) have recently been surveyedand now have population estimates showing probable increases

For example a first-ever Kara Sea population estimate completed in late 2014potentially adds another 3200 or so bears to the global total29 This estimate (range2700ndash3500) derivedbyRussianbiologists was added to theofficial global countpub-lished in 2015 by the IUCN Red List21 A former ball-park estimate was about 200018

suggesting an increase may have taken place

Figure 2 Global polar bear population status assessment even better than thisFigures from the IUCN Polar Bear Specialist Group assessment (2013) and EnvironmentCanada (May 2014)30 Brown data deficient red declining yellow likely decline lightblue likely stable dark blue stable light green likely increase dark green increase

More recent surveys show BB BS KB and KS are stable or likely increasing2

3

3 Abrupt summer sea ice decline has not affectedpolar bear numbers as predicted

Arctic sea ice has declined since satellite records began in 1979 but polar bears haveso far adjusted well to this change especially to the sudden decline to reduced sum-mer sea ice levels that have been the norm since 2007 The degree of abrupt dropin summer sea ice that occurred in 2007 was not predicted by experts to occur untilmid-century However the predicted decimation of polar bears worldwide expectedunder mid-century conditions (Figure 3)31 ndash which entailed a loss of 23 of the globaltotal (to only about 6660ndash8325 bears) as well as the total extermination of 10 entiresubpopulations ndash not only failed to occur it did not come even close to happening32

If the experts had been right back in 2007 there would be no polar bears at all inthe Southern Beaufort or Western Hudson Bay this year33 There is also evidence thatless summer ice in the Central Canadian Arctic has already been beneficial for polarbears34 an advantage not expected until later this century This is due in part to thefact that less summer ice is good for ringed seals - on which polar bears prey ndash whichfeed primarily during the ice-free season (see Section 5) and which do best with first-year ice cover during the spring birthing and mating seasons

(a) (b)

Figure 3 Predicted sea ice changes versus outturn(a) Predictions based on 2004 data for 2020 (light grey) 2050 (mid grey) and 2080(dark grey) These were used in 2007 to predict a 66 decline in global polar bearnumbers (b) Situation as at 10 September 2012 an example of the sea ice extent

experienced in since 200735 See Crockford 2017 for details2

4

4 Chukchi Sea population is thrivingThe results of a new study published in 2013 were a direct contradiction of the re-peatedmessage that recent large sea-ice declines in late summer hadput these bearsin peril36 The paper showed that Chukchi polar bears are doingbetter than theywerein the 1980s37 and better than any others except the bears of Foxe Basin (northernHudson Bay) who are doing exceptionally well38

There is still no official population estimate for the Chukchi Sea the population isofficially listed as zero but was previously estimated at about 2000 individuals How-ever it appears that record-breaking sea-ice levels in September 2007 the lowestsince 1979 had no discernible effect on Chukchi Sea polar bears39 as confirmed byresearch up to 2016240 As a result the status of this population was upgraded fromlsquodecliningrsquo to lsquodata deficientrsquo by the PBSG in 201341 Despite the gloomy predictions alonger-than-average ice-freeperiodhas actually beengood forChukchi polar bears42

5 More preymeans healthier polar bearsThe reason Chukchi Sea polar bears did so well with an extended open-water sea-son was because ringed seals their primary prey do most of their feeding in ice-freesummer waters More fat seals mean more fat seal pups the following spring for po-lar bears A recent study found that in recent years with extensive September sea-iceminimums the summer feedingperiod for sealswas extendedand theybecameextrafat43 This meant that some seals provided a more energy-rich food source for polarbears over the following fall and winter an immediate benefit to the bears In addi-tion well-fed female ringed seals produced fat healthy pups the next spring whichmeant more food for polar bears when they needed it the most

Between 2008 and 2011 both ringed seals and polar bears did better than eitherhad done in the 1980s when summer sea ice coverage was more extensive Oddlyin March 2013 less than six months after ringed seals were placed on the Americanlist of species lsquothreatenedrsquo with extinction44 ringed seal biologists were reporting totheir peers that the results of their Chukchi Sea research contradicted their dire pre-dictions45 Surprisingly to them less summer sea ice was better for ringed seals notworse In July 2014 a judge decreed that the 2012 decision to list bearded seals inAlaska as lsquothreatenedrsquo was deficient and that there were no near-term threats Thejudge called it lsquoan abuse of discretionrsquo46

The USA stands out as the only nation that insists that Arctic seals have been (orwill be shortly) harmed by recent declines in summer sea ice47 which made it all themore surprising that in September 2017 the US Fish andWildlife Service announcedit would not pursue a plan to list Pacific walrus as lsquothreatenedrsquo with extinction underthe Endangered Species Act48 Their experts concluded there was no evidence of on-going harm or an imminent threat to walrus survival

5

6 Polar bears are adaptablePolar bears have been shown to move from areas with unsuitable ice to areas withbetter ice conditions even over the short term This is strong evidence of their abilityto adapt to changing sea ice Recently it was noted that a number of bears from theBarents Seawhere sea-ice coverage is strongly influencedbyvariations in theAtlanticMultidecadal Oscillation49 moved to the islands of the Franz Josef Land archipelagoin the Kara Sea where there has beenmore predictable ice cover50 This is just one ex-ample of polar bear flexibility A past example was the movement of Southern Beau-fort bears into the Chukchi Sea during the catastrophic 1974ndash1976 episode of thickspring ice in the Eastern Beaufort Flexibility in choosing maternity dens (onshorevs sea ice) as well as variability in feeding areas (nearshore vs offshore)51 give polarbears the resilience they need to survive as a species

7 Southern Beaufort numbers have reboundedAccording to a preliminary US Fish amp Wildlife Service survey Southern Beaufort bearnumberswerehigher in the fall of 2012 than theyhadbeen in theprevious tenyears52

indicating a recovery from the dramatic decline (25ndash50) that occurred between2004 and 2006 because of the effects of thick spring sea ice53 For unknown rea-sons the newly-developed models used to estimate Southern Beaufort populationsize used only data up until 2010 even though mark-recapture data up until 2012were available54 This is known because the data was used for another study seeSection 8 The failure of thick spring ice conditions to recur in recent years and theearly formation and expansion of spring polynyas in the eastern Beaufort have likelybeenbeneficial for polar bears and seals55 resulting in the rare sighting of at least oneset of healthy triplet cubs in 201656

8 Barents Sea numbers have increasedThe Svalbard portion of the Barents Sea subpopulation was surveyed in 2015 andwas initially reported to have increased by 42 over the count performed in 200457

The just-publishedpaper confirms that a 42 increase in abundance indeedoccurred(685 bears in 2004 versus 973 bears in 2015)58 However due to the large uncertainty(broad error ranges) in the estimates involved even a 42 increase was not statis-tically significant This point was strongly emphasized by the PBSG59 in their recentstatus update for the Barents Sea

Becauseof theoverlapping confidence intervals it cannot be concluded that theBS subpopulation has grown60

The authors of the Svalbard survey however had this to say

6

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

Contents

About the author vii

Executive summary ix

Introduction 1

1 A conservation success story 1

2 Fewer populations in decline 1

3 Abrupt summer sea icedeclinehasnot affectedpolar bearnumbersas predicted 4

4 Chukchi Sea population is thriving 5

5 More prey means healthier polar bears 5

6 Polar bears are adaptable 6

7 Southern Beaufort numbers have rebounded 6

8 Barents Sea numbers have increased 6

9 Low sea ice in 2012 had no harmful effect on Southern Beaufortbear numbers 7

10 Other species impacted by high polar bear numbers 7

11 Western Hudson Bay population numbers are stable 7

12 Hudson Bay sea ice is not changing much 10

13 Problem bears in Churchill are not lean or starving 10

14 Churchill Manitoba had the most problem bears in 1983 and 2016 10

15 Marginal sea ice declines during the feeding period 11

16 No evidence that subsistence hunting is affecting bear populations 12

17 Stressful research methods have been curtailed 12

18 No recent reports of polar bear cannibalism 13

v

19 Polar bears appear unaffected by pollution 14

20 Polar bears have survived past warm periods 14

Conclusion 14

Notes 16

About the authorDr Susan Crockford is an evolutionary biologist and has been working for 35 yearsin archaeozoology paleozoology and forensic zoology She is an adjunct professor attheUniversity of Victoria British Columbia butworks full time for a private consultingcompany she co-owns (Pacific Identifications Inc) She is the author of Rhythms ofLife Thyroid Hormone and the Origin of Species Eaten A Novel (a polar bear attackthriller) Polar Bear Facts and Myths (for ages seven and up also available in Frenchand German) Polar Bears Have Big Feet (for preschoolers) and the fully referencedPolar Bears Outstanding Survivors of Climate Change1 as well as a scientific paper onpolar bear conservation status2 She has authored several earlier briefing papers andvideos for GWPF on the subjects of polar bears and walrus345678 Susan Crockfordblogs at wwwpolarbearsciencecom

vii

Executive summary1 Polar bears are still a conservation success story there are more polar bears

now than there were 40 years ago

2 Fewer populations are in decline than in 2010 (only one officially) and only sixare data deficient (down from nine)

3 Abrupt summer sea ice decline has not affected polar bear numbers as pre-dicted even though sea ice levels dropped to mid-century levels in 2007 theexpected decimation of polar bears failed to occur

4 The Chukchi Sea population is thriving despite a pronounced lengthening ofthe ice-free season since 2007

5 Less sea ice in the summer in the Chukchi Sea has meant a healthy prey basefor polar bears because ringed seals feed primarily in the ice-free season

6 Polar bears have shown themselves to be adaptable to changing ice conditionsin several regions

7 Southern Beaufort numbers have rebounded since the last survey count

8 Barents Sea numbers have probably increased since 2005 and have definitelynot declined despite much less sea ice cover

9 There is no evidence that record-low summer sea ice in 2012 had a harmfuleffect on Southern Beaufort bear numbers

10 Other species are being negatively impacted by high polar bear numbers es-pecially nesting sea birds and ducks

11 Western Hudson Bay population numbers have been stable since 2004 despitewhat scientists are telling the media

12 Hudson Bay sea ice has not changed since about 1999 the breakup dates andfreeze-up dates are highly variable but the ice-free period was not any longerin 2015 than it was in 2004 However this fall freeze-up is shaping up to be theearliest in decades

13 Problem bears in Churchill are not lean or starving

14 Churchill Manitoba had the most problem bears in 1983 and 2016 which werelate freeze-up years but many of the incidents in 2016 can be attributed to in-creased vigilance on the part of patrol officers after an attack in 2013

15 There have been only marginal sea-ice declines during the feeding period inspring when polar bears need sea ice the most

16 The is no evidence that subsistence hunting is affecting bear populations

17 Stressful research methods have been curtailed in much of Canada

ix

18 There have been no reports of polar bear cannibalism since 2011

19 Polar bears appear unaffected by pollution studies suggest only that harm istheoretically possible not that it has happened

20 Polar bears have survived past warm periods which is evidence they have theability to survive future warm periods

Conclusion

bull Polar bears are thriving they are not currently threatened with extinction

bull Tens of thousands of polar bears did not die as a result of more than a decadeof low summer sea ice as was predicted

bull Polar bears donrsquot need sea ice in late summerearly fall as long as they are well-fed in the spring

x

IntroductionJust in time for Polar Bears Internationalrsquos self-proclaimed9 fall Polar Bear Week (5ndash11November 2017)10 here is a new resource for cooling the polar bear spin Irsquove up-dated my 2015 summary of reasons not to worry about polar bears which is nowmore than two years old11 In this new version you will find links to supporting in-formation including published papers and fully referenced blog posts of mine thatprovide backgroundmaps andbibliographies although someof themost importantgraphs andmaps have been reproduced here I hope you find it a useful resource forrefuting the pessimism1213 and prophecies of catastrophe14 about the future of po-lar bears Please feel free to share it As global leaders meet in Bonn for COP23 (6ndash17November 2017)15 itrsquos time to celebrate the proven resilience of polar bears to theirever-changing Arctic environment

1 A conservation success storyPolar bears are still a conservation success story16 With the estimated global popu-lation almost certainly greater than 2800017 we can say for sure that there are morepolarbearsnowthan therewere40years ago (Figure1)18 Sadly althoughcompletinga global survey was one of the primary objectives of the Polar Bear Specialist Group(PBSG) at its inception 49 years ago it has so far been unable to do so because at leastfour subpopulations have never been counted The PBSG global estimate was listedin July 2014 as lsquoapproximately 25000rsquo bears19 This number has not been revised20

even though the estimate PBSG members provided the International Union for theConservation of Nature (IUCN) for its 2015 assessment was 22000ndash31000 or about2600021 Surveys completed or published since bring the total higher still2

Even with the lack of precision inherent in these estimates global numbers arestill too high to qualify the polar bear as lsquovulnerablersquo to or lsquothreatenedrsquo with extinc-tion based on current population levels22 Polar bears today are also well distributedthroughout their available habitat (winter sea ice)23 which is a recognized charac-teristic of a healthy species All concerns expressed regarding polar bear survival areabout the future24

2 Fewer populations in declineA recent status assessment for polar bears published by Environment Canada inMay201426 showed only two subpopulations are lsquolikely decliningrsquo down from four listedby the PBSG as declining in 2013 and seven in 2010 (Figure 2)27 Baffin Bay whichearned its lsquolikely decliningrsquo status due to suspicions of overharvesting (not sea ice de-cline) was reported in 2017 to be likely stable28 Kane Basin assessed as lsquodecliningrsquoin 2010 and 2013 (but lsquodata deficientrsquo in 2014) was reported in 2017 to be lsquostablersquo or

1

0

5

10

15

20

25

30

0

5

10

15

20

25

30

1950 1960 1970 1980 1990 2000 2010

1950 1960 1970 1980 1990 2000 2010

(a) Official estimate

(b) Unofficial estimate

Figure 1 Official estimates of polar bear numbersUpper graph uses totals reported in PBSG status tables (to 2013) with minmax lowergraph uses the same figures but adds back in the so-called lsquoinaccuratersquo estimates

dropped between 2005 and 2013 (in 2014 the PBSG finally did the same)25 The 1960figure is a ballpark estimate Further detail can be found at my website18 and Crockford

20172

2

lsquolikely increasingrsquo28 (but see Section 10) This leaves only the Southern Beaufort bearpopulation as lsquolikely decliningrsquo and even this is a highly questionable assessment (seeSection 7) Note also that the number of subpopulation considered lsquodata deficientrsquo(Figure 2 areas in brown) has been reduced from nine in 2014 to six in 2017 threebear populations (Barents Sea Kara Sea and Kane Basin) have recently been surveyedand now have population estimates showing probable increases

For example a first-ever Kara Sea population estimate completed in late 2014potentially adds another 3200 or so bears to the global total29 This estimate (range2700ndash3500) derivedbyRussianbiologists was added to theofficial global countpub-lished in 2015 by the IUCN Red List21 A former ball-park estimate was about 200018

suggesting an increase may have taken place

Figure 2 Global polar bear population status assessment even better than thisFigures from the IUCN Polar Bear Specialist Group assessment (2013) and EnvironmentCanada (May 2014)30 Brown data deficient red declining yellow likely decline lightblue likely stable dark blue stable light green likely increase dark green increase

More recent surveys show BB BS KB and KS are stable or likely increasing2

3

3 Abrupt summer sea ice decline has not affectedpolar bear numbers as predicted

Arctic sea ice has declined since satellite records began in 1979 but polar bears haveso far adjusted well to this change especially to the sudden decline to reduced sum-mer sea ice levels that have been the norm since 2007 The degree of abrupt dropin summer sea ice that occurred in 2007 was not predicted by experts to occur untilmid-century However the predicted decimation of polar bears worldwide expectedunder mid-century conditions (Figure 3)31 ndash which entailed a loss of 23 of the globaltotal (to only about 6660ndash8325 bears) as well as the total extermination of 10 entiresubpopulations ndash not only failed to occur it did not come even close to happening32

If the experts had been right back in 2007 there would be no polar bears at all inthe Southern Beaufort or Western Hudson Bay this year33 There is also evidence thatless summer ice in the Central Canadian Arctic has already been beneficial for polarbears34 an advantage not expected until later this century This is due in part to thefact that less summer ice is good for ringed seals - on which polar bears prey ndash whichfeed primarily during the ice-free season (see Section 5) and which do best with first-year ice cover during the spring birthing and mating seasons

(a) (b)

Figure 3 Predicted sea ice changes versus outturn(a) Predictions based on 2004 data for 2020 (light grey) 2050 (mid grey) and 2080(dark grey) These were used in 2007 to predict a 66 decline in global polar bearnumbers (b) Situation as at 10 September 2012 an example of the sea ice extent

experienced in since 200735 See Crockford 2017 for details2

4

4 Chukchi Sea population is thrivingThe results of a new study published in 2013 were a direct contradiction of the re-peatedmessage that recent large sea-ice declines in late summer hadput these bearsin peril36 The paper showed that Chukchi polar bears are doingbetter than theywerein the 1980s37 and better than any others except the bears of Foxe Basin (northernHudson Bay) who are doing exceptionally well38

There is still no official population estimate for the Chukchi Sea the population isofficially listed as zero but was previously estimated at about 2000 individuals How-ever it appears that record-breaking sea-ice levels in September 2007 the lowestsince 1979 had no discernible effect on Chukchi Sea polar bears39 as confirmed byresearch up to 2016240 As a result the status of this population was upgraded fromlsquodecliningrsquo to lsquodata deficientrsquo by the PBSG in 201341 Despite the gloomy predictions alonger-than-average ice-freeperiodhas actually beengood forChukchi polar bears42

5 More preymeans healthier polar bearsThe reason Chukchi Sea polar bears did so well with an extended open-water sea-son was because ringed seals their primary prey do most of their feeding in ice-freesummer waters More fat seals mean more fat seal pups the following spring for po-lar bears A recent study found that in recent years with extensive September sea-iceminimums the summer feedingperiod for sealswas extendedand theybecameextrafat43 This meant that some seals provided a more energy-rich food source for polarbears over the following fall and winter an immediate benefit to the bears In addi-tion well-fed female ringed seals produced fat healthy pups the next spring whichmeant more food for polar bears when they needed it the most

Between 2008 and 2011 both ringed seals and polar bears did better than eitherhad done in the 1980s when summer sea ice coverage was more extensive Oddlyin March 2013 less than six months after ringed seals were placed on the Americanlist of species lsquothreatenedrsquo with extinction44 ringed seal biologists were reporting totheir peers that the results of their Chukchi Sea research contradicted their dire pre-dictions45 Surprisingly to them less summer sea ice was better for ringed seals notworse In July 2014 a judge decreed that the 2012 decision to list bearded seals inAlaska as lsquothreatenedrsquo was deficient and that there were no near-term threats Thejudge called it lsquoan abuse of discretionrsquo46

The USA stands out as the only nation that insists that Arctic seals have been (orwill be shortly) harmed by recent declines in summer sea ice47 which made it all themore surprising that in September 2017 the US Fish andWildlife Service announcedit would not pursue a plan to list Pacific walrus as lsquothreatenedrsquo with extinction underthe Endangered Species Act48 Their experts concluded there was no evidence of on-going harm or an imminent threat to walrus survival

5

6 Polar bears are adaptablePolar bears have been shown to move from areas with unsuitable ice to areas withbetter ice conditions even over the short term This is strong evidence of their abilityto adapt to changing sea ice Recently it was noted that a number of bears from theBarents Seawhere sea-ice coverage is strongly influencedbyvariations in theAtlanticMultidecadal Oscillation49 moved to the islands of the Franz Josef Land archipelagoin the Kara Sea where there has beenmore predictable ice cover50 This is just one ex-ample of polar bear flexibility A past example was the movement of Southern Beau-fort bears into the Chukchi Sea during the catastrophic 1974ndash1976 episode of thickspring ice in the Eastern Beaufort Flexibility in choosing maternity dens (onshorevs sea ice) as well as variability in feeding areas (nearshore vs offshore)51 give polarbears the resilience they need to survive as a species

7 Southern Beaufort numbers have reboundedAccording to a preliminary US Fish amp Wildlife Service survey Southern Beaufort bearnumberswerehigher in the fall of 2012 than theyhadbeen in theprevious tenyears52

indicating a recovery from the dramatic decline (25ndash50) that occurred between2004 and 2006 because of the effects of thick spring sea ice53 For unknown rea-sons the newly-developed models used to estimate Southern Beaufort populationsize used only data up until 2010 even though mark-recapture data up until 2012were available54 This is known because the data was used for another study seeSection 8 The failure of thick spring ice conditions to recur in recent years and theearly formation and expansion of spring polynyas in the eastern Beaufort have likelybeenbeneficial for polar bears and seals55 resulting in the rare sighting of at least oneset of healthy triplet cubs in 201656

8 Barents Sea numbers have increasedThe Svalbard portion of the Barents Sea subpopulation was surveyed in 2015 andwas initially reported to have increased by 42 over the count performed in 200457

The just-publishedpaper confirms that a 42 increase in abundance indeedoccurred(685 bears in 2004 versus 973 bears in 2015)58 However due to the large uncertainty(broad error ranges) in the estimates involved even a 42 increase was not statis-tically significant This point was strongly emphasized by the PBSG59 in their recentstatus update for the Barents Sea

Becauseof theoverlapping confidence intervals it cannot be concluded that theBS subpopulation has grown60

The authors of the Svalbard survey however had this to say

6

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

19 Polar bears appear unaffected by pollution 14

20 Polar bears have survived past warm periods 14

Conclusion 14

Notes 16

About the authorDr Susan Crockford is an evolutionary biologist and has been working for 35 yearsin archaeozoology paleozoology and forensic zoology She is an adjunct professor attheUniversity of Victoria British Columbia butworks full time for a private consultingcompany she co-owns (Pacific Identifications Inc) She is the author of Rhythms ofLife Thyroid Hormone and the Origin of Species Eaten A Novel (a polar bear attackthriller) Polar Bear Facts and Myths (for ages seven and up also available in Frenchand German) Polar Bears Have Big Feet (for preschoolers) and the fully referencedPolar Bears Outstanding Survivors of Climate Change1 as well as a scientific paper onpolar bear conservation status2 She has authored several earlier briefing papers andvideos for GWPF on the subjects of polar bears and walrus345678 Susan Crockfordblogs at wwwpolarbearsciencecom

vii

Executive summary1 Polar bears are still a conservation success story there are more polar bears

now than there were 40 years ago

2 Fewer populations are in decline than in 2010 (only one officially) and only sixare data deficient (down from nine)

3 Abrupt summer sea ice decline has not affected polar bear numbers as pre-dicted even though sea ice levels dropped to mid-century levels in 2007 theexpected decimation of polar bears failed to occur

4 The Chukchi Sea population is thriving despite a pronounced lengthening ofthe ice-free season since 2007

5 Less sea ice in the summer in the Chukchi Sea has meant a healthy prey basefor polar bears because ringed seals feed primarily in the ice-free season

6 Polar bears have shown themselves to be adaptable to changing ice conditionsin several regions

7 Southern Beaufort numbers have rebounded since the last survey count

8 Barents Sea numbers have probably increased since 2005 and have definitelynot declined despite much less sea ice cover

9 There is no evidence that record-low summer sea ice in 2012 had a harmfuleffect on Southern Beaufort bear numbers

10 Other species are being negatively impacted by high polar bear numbers es-pecially nesting sea birds and ducks

11 Western Hudson Bay population numbers have been stable since 2004 despitewhat scientists are telling the media

12 Hudson Bay sea ice has not changed since about 1999 the breakup dates andfreeze-up dates are highly variable but the ice-free period was not any longerin 2015 than it was in 2004 However this fall freeze-up is shaping up to be theearliest in decades

13 Problem bears in Churchill are not lean or starving

14 Churchill Manitoba had the most problem bears in 1983 and 2016 which werelate freeze-up years but many of the incidents in 2016 can be attributed to in-creased vigilance on the part of patrol officers after an attack in 2013

15 There have been only marginal sea-ice declines during the feeding period inspring when polar bears need sea ice the most

16 The is no evidence that subsistence hunting is affecting bear populations

17 Stressful research methods have been curtailed in much of Canada

ix

18 There have been no reports of polar bear cannibalism since 2011

19 Polar bears appear unaffected by pollution studies suggest only that harm istheoretically possible not that it has happened

20 Polar bears have survived past warm periods which is evidence they have theability to survive future warm periods

Conclusion

bull Polar bears are thriving they are not currently threatened with extinction

bull Tens of thousands of polar bears did not die as a result of more than a decadeof low summer sea ice as was predicted

bull Polar bears donrsquot need sea ice in late summerearly fall as long as they are well-fed in the spring

x

IntroductionJust in time for Polar Bears Internationalrsquos self-proclaimed9 fall Polar Bear Week (5ndash11November 2017)10 here is a new resource for cooling the polar bear spin Irsquove up-dated my 2015 summary of reasons not to worry about polar bears which is nowmore than two years old11 In this new version you will find links to supporting in-formation including published papers and fully referenced blog posts of mine thatprovide backgroundmaps andbibliographies although someof themost importantgraphs andmaps have been reproduced here I hope you find it a useful resource forrefuting the pessimism1213 and prophecies of catastrophe14 about the future of po-lar bears Please feel free to share it As global leaders meet in Bonn for COP23 (6ndash17November 2017)15 itrsquos time to celebrate the proven resilience of polar bears to theirever-changing Arctic environment

1 A conservation success storyPolar bears are still a conservation success story16 With the estimated global popu-lation almost certainly greater than 2800017 we can say for sure that there are morepolarbearsnowthan therewere40years ago (Figure1)18 Sadly althoughcompletinga global survey was one of the primary objectives of the Polar Bear Specialist Group(PBSG) at its inception 49 years ago it has so far been unable to do so because at leastfour subpopulations have never been counted The PBSG global estimate was listedin July 2014 as lsquoapproximately 25000rsquo bears19 This number has not been revised20

even though the estimate PBSG members provided the International Union for theConservation of Nature (IUCN) for its 2015 assessment was 22000ndash31000 or about2600021 Surveys completed or published since bring the total higher still2

Even with the lack of precision inherent in these estimates global numbers arestill too high to qualify the polar bear as lsquovulnerablersquo to or lsquothreatenedrsquo with extinc-tion based on current population levels22 Polar bears today are also well distributedthroughout their available habitat (winter sea ice)23 which is a recognized charac-teristic of a healthy species All concerns expressed regarding polar bear survival areabout the future24

2 Fewer populations in declineA recent status assessment for polar bears published by Environment Canada inMay201426 showed only two subpopulations are lsquolikely decliningrsquo down from four listedby the PBSG as declining in 2013 and seven in 2010 (Figure 2)27 Baffin Bay whichearned its lsquolikely decliningrsquo status due to suspicions of overharvesting (not sea ice de-cline) was reported in 2017 to be likely stable28 Kane Basin assessed as lsquodecliningrsquoin 2010 and 2013 (but lsquodata deficientrsquo in 2014) was reported in 2017 to be lsquostablersquo or

1

0

5

10

15

20

25

30

0

5

10

15

20

25

30

1950 1960 1970 1980 1990 2000 2010

1950 1960 1970 1980 1990 2000 2010

(a) Official estimate

(b) Unofficial estimate

Figure 1 Official estimates of polar bear numbersUpper graph uses totals reported in PBSG status tables (to 2013) with minmax lowergraph uses the same figures but adds back in the so-called lsquoinaccuratersquo estimates

dropped between 2005 and 2013 (in 2014 the PBSG finally did the same)25 The 1960figure is a ballpark estimate Further detail can be found at my website18 and Crockford

20172

2

lsquolikely increasingrsquo28 (but see Section 10) This leaves only the Southern Beaufort bearpopulation as lsquolikely decliningrsquo and even this is a highly questionable assessment (seeSection 7) Note also that the number of subpopulation considered lsquodata deficientrsquo(Figure 2 areas in brown) has been reduced from nine in 2014 to six in 2017 threebear populations (Barents Sea Kara Sea and Kane Basin) have recently been surveyedand now have population estimates showing probable increases

For example a first-ever Kara Sea population estimate completed in late 2014potentially adds another 3200 or so bears to the global total29 This estimate (range2700ndash3500) derivedbyRussianbiologists was added to theofficial global countpub-lished in 2015 by the IUCN Red List21 A former ball-park estimate was about 200018

suggesting an increase may have taken place

Figure 2 Global polar bear population status assessment even better than thisFigures from the IUCN Polar Bear Specialist Group assessment (2013) and EnvironmentCanada (May 2014)30 Brown data deficient red declining yellow likely decline lightblue likely stable dark blue stable light green likely increase dark green increase

More recent surveys show BB BS KB and KS are stable or likely increasing2

3

3 Abrupt summer sea ice decline has not affectedpolar bear numbers as predicted

Arctic sea ice has declined since satellite records began in 1979 but polar bears haveso far adjusted well to this change especially to the sudden decline to reduced sum-mer sea ice levels that have been the norm since 2007 The degree of abrupt dropin summer sea ice that occurred in 2007 was not predicted by experts to occur untilmid-century However the predicted decimation of polar bears worldwide expectedunder mid-century conditions (Figure 3)31 ndash which entailed a loss of 23 of the globaltotal (to only about 6660ndash8325 bears) as well as the total extermination of 10 entiresubpopulations ndash not only failed to occur it did not come even close to happening32

If the experts had been right back in 2007 there would be no polar bears at all inthe Southern Beaufort or Western Hudson Bay this year33 There is also evidence thatless summer ice in the Central Canadian Arctic has already been beneficial for polarbears34 an advantage not expected until later this century This is due in part to thefact that less summer ice is good for ringed seals - on which polar bears prey ndash whichfeed primarily during the ice-free season (see Section 5) and which do best with first-year ice cover during the spring birthing and mating seasons

(a) (b)

Figure 3 Predicted sea ice changes versus outturn(a) Predictions based on 2004 data for 2020 (light grey) 2050 (mid grey) and 2080(dark grey) These were used in 2007 to predict a 66 decline in global polar bearnumbers (b) Situation as at 10 September 2012 an example of the sea ice extent

experienced in since 200735 See Crockford 2017 for details2

4

4 Chukchi Sea population is thrivingThe results of a new study published in 2013 were a direct contradiction of the re-peatedmessage that recent large sea-ice declines in late summer hadput these bearsin peril36 The paper showed that Chukchi polar bears are doingbetter than theywerein the 1980s37 and better than any others except the bears of Foxe Basin (northernHudson Bay) who are doing exceptionally well38

There is still no official population estimate for the Chukchi Sea the population isofficially listed as zero but was previously estimated at about 2000 individuals How-ever it appears that record-breaking sea-ice levels in September 2007 the lowestsince 1979 had no discernible effect on Chukchi Sea polar bears39 as confirmed byresearch up to 2016240 As a result the status of this population was upgraded fromlsquodecliningrsquo to lsquodata deficientrsquo by the PBSG in 201341 Despite the gloomy predictions alonger-than-average ice-freeperiodhas actually beengood forChukchi polar bears42

5 More preymeans healthier polar bearsThe reason Chukchi Sea polar bears did so well with an extended open-water sea-son was because ringed seals their primary prey do most of their feeding in ice-freesummer waters More fat seals mean more fat seal pups the following spring for po-lar bears A recent study found that in recent years with extensive September sea-iceminimums the summer feedingperiod for sealswas extendedand theybecameextrafat43 This meant that some seals provided a more energy-rich food source for polarbears over the following fall and winter an immediate benefit to the bears In addi-tion well-fed female ringed seals produced fat healthy pups the next spring whichmeant more food for polar bears when they needed it the most

Between 2008 and 2011 both ringed seals and polar bears did better than eitherhad done in the 1980s when summer sea ice coverage was more extensive Oddlyin March 2013 less than six months after ringed seals were placed on the Americanlist of species lsquothreatenedrsquo with extinction44 ringed seal biologists were reporting totheir peers that the results of their Chukchi Sea research contradicted their dire pre-dictions45 Surprisingly to them less summer sea ice was better for ringed seals notworse In July 2014 a judge decreed that the 2012 decision to list bearded seals inAlaska as lsquothreatenedrsquo was deficient and that there were no near-term threats Thejudge called it lsquoan abuse of discretionrsquo46

The USA stands out as the only nation that insists that Arctic seals have been (orwill be shortly) harmed by recent declines in summer sea ice47 which made it all themore surprising that in September 2017 the US Fish andWildlife Service announcedit would not pursue a plan to list Pacific walrus as lsquothreatenedrsquo with extinction underthe Endangered Species Act48 Their experts concluded there was no evidence of on-going harm or an imminent threat to walrus survival

5

6 Polar bears are adaptablePolar bears have been shown to move from areas with unsuitable ice to areas withbetter ice conditions even over the short term This is strong evidence of their abilityto adapt to changing sea ice Recently it was noted that a number of bears from theBarents Seawhere sea-ice coverage is strongly influencedbyvariations in theAtlanticMultidecadal Oscillation49 moved to the islands of the Franz Josef Land archipelagoin the Kara Sea where there has beenmore predictable ice cover50 This is just one ex-ample of polar bear flexibility A past example was the movement of Southern Beau-fort bears into the Chukchi Sea during the catastrophic 1974ndash1976 episode of thickspring ice in the Eastern Beaufort Flexibility in choosing maternity dens (onshorevs sea ice) as well as variability in feeding areas (nearshore vs offshore)51 give polarbears the resilience they need to survive as a species

7 Southern Beaufort numbers have reboundedAccording to a preliminary US Fish amp Wildlife Service survey Southern Beaufort bearnumberswerehigher in the fall of 2012 than theyhadbeen in theprevious tenyears52

indicating a recovery from the dramatic decline (25ndash50) that occurred between2004 and 2006 because of the effects of thick spring sea ice53 For unknown rea-sons the newly-developed models used to estimate Southern Beaufort populationsize used only data up until 2010 even though mark-recapture data up until 2012were available54 This is known because the data was used for another study seeSection 8 The failure of thick spring ice conditions to recur in recent years and theearly formation and expansion of spring polynyas in the eastern Beaufort have likelybeenbeneficial for polar bears and seals55 resulting in the rare sighting of at least oneset of healthy triplet cubs in 201656

8 Barents Sea numbers have increasedThe Svalbard portion of the Barents Sea subpopulation was surveyed in 2015 andwas initially reported to have increased by 42 over the count performed in 200457

The just-publishedpaper confirms that a 42 increase in abundance indeedoccurred(685 bears in 2004 versus 973 bears in 2015)58 However due to the large uncertainty(broad error ranges) in the estimates involved even a 42 increase was not statis-tically significant This point was strongly emphasized by the PBSG59 in their recentstatus update for the Barents Sea

Becauseof theoverlapping confidence intervals it cannot be concluded that theBS subpopulation has grown60

The authors of the Svalbard survey however had this to say

6

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

About the authorDr Susan Crockford is an evolutionary biologist and has been working for 35 yearsin archaeozoology paleozoology and forensic zoology She is an adjunct professor attheUniversity of Victoria British Columbia butworks full time for a private consultingcompany she co-owns (Pacific Identifications Inc) She is the author of Rhythms ofLife Thyroid Hormone and the Origin of Species Eaten A Novel (a polar bear attackthriller) Polar Bear Facts and Myths (for ages seven and up also available in Frenchand German) Polar Bears Have Big Feet (for preschoolers) and the fully referencedPolar Bears Outstanding Survivors of Climate Change1 as well as a scientific paper onpolar bear conservation status2 She has authored several earlier briefing papers andvideos for GWPF on the subjects of polar bears and walrus345678 Susan Crockfordblogs at wwwpolarbearsciencecom

vii

Executive summary1 Polar bears are still a conservation success story there are more polar bears

now than there were 40 years ago

2 Fewer populations are in decline than in 2010 (only one officially) and only sixare data deficient (down from nine)

3 Abrupt summer sea ice decline has not affected polar bear numbers as pre-dicted even though sea ice levels dropped to mid-century levels in 2007 theexpected decimation of polar bears failed to occur

4 The Chukchi Sea population is thriving despite a pronounced lengthening ofthe ice-free season since 2007

5 Less sea ice in the summer in the Chukchi Sea has meant a healthy prey basefor polar bears because ringed seals feed primarily in the ice-free season

6 Polar bears have shown themselves to be adaptable to changing ice conditionsin several regions

7 Southern Beaufort numbers have rebounded since the last survey count

8 Barents Sea numbers have probably increased since 2005 and have definitelynot declined despite much less sea ice cover

9 There is no evidence that record-low summer sea ice in 2012 had a harmfuleffect on Southern Beaufort bear numbers

10 Other species are being negatively impacted by high polar bear numbers es-pecially nesting sea birds and ducks

11 Western Hudson Bay population numbers have been stable since 2004 despitewhat scientists are telling the media

12 Hudson Bay sea ice has not changed since about 1999 the breakup dates andfreeze-up dates are highly variable but the ice-free period was not any longerin 2015 than it was in 2004 However this fall freeze-up is shaping up to be theearliest in decades

13 Problem bears in Churchill are not lean or starving

14 Churchill Manitoba had the most problem bears in 1983 and 2016 which werelate freeze-up years but many of the incidents in 2016 can be attributed to in-creased vigilance on the part of patrol officers after an attack in 2013

15 There have been only marginal sea-ice declines during the feeding period inspring when polar bears need sea ice the most

16 The is no evidence that subsistence hunting is affecting bear populations

17 Stressful research methods have been curtailed in much of Canada

ix

18 There have been no reports of polar bear cannibalism since 2011

19 Polar bears appear unaffected by pollution studies suggest only that harm istheoretically possible not that it has happened

20 Polar bears have survived past warm periods which is evidence they have theability to survive future warm periods

Conclusion

bull Polar bears are thriving they are not currently threatened with extinction

bull Tens of thousands of polar bears did not die as a result of more than a decadeof low summer sea ice as was predicted

bull Polar bears donrsquot need sea ice in late summerearly fall as long as they are well-fed in the spring

x

IntroductionJust in time for Polar Bears Internationalrsquos self-proclaimed9 fall Polar Bear Week (5ndash11November 2017)10 here is a new resource for cooling the polar bear spin Irsquove up-dated my 2015 summary of reasons not to worry about polar bears which is nowmore than two years old11 In this new version you will find links to supporting in-formation including published papers and fully referenced blog posts of mine thatprovide backgroundmaps andbibliographies although someof themost importantgraphs andmaps have been reproduced here I hope you find it a useful resource forrefuting the pessimism1213 and prophecies of catastrophe14 about the future of po-lar bears Please feel free to share it As global leaders meet in Bonn for COP23 (6ndash17November 2017)15 itrsquos time to celebrate the proven resilience of polar bears to theirever-changing Arctic environment

1 A conservation success storyPolar bears are still a conservation success story16 With the estimated global popu-lation almost certainly greater than 2800017 we can say for sure that there are morepolarbearsnowthan therewere40years ago (Figure1)18 Sadly althoughcompletinga global survey was one of the primary objectives of the Polar Bear Specialist Group(PBSG) at its inception 49 years ago it has so far been unable to do so because at leastfour subpopulations have never been counted The PBSG global estimate was listedin July 2014 as lsquoapproximately 25000rsquo bears19 This number has not been revised20

even though the estimate PBSG members provided the International Union for theConservation of Nature (IUCN) for its 2015 assessment was 22000ndash31000 or about2600021 Surveys completed or published since bring the total higher still2

Even with the lack of precision inherent in these estimates global numbers arestill too high to qualify the polar bear as lsquovulnerablersquo to or lsquothreatenedrsquo with extinc-tion based on current population levels22 Polar bears today are also well distributedthroughout their available habitat (winter sea ice)23 which is a recognized charac-teristic of a healthy species All concerns expressed regarding polar bear survival areabout the future24

2 Fewer populations in declineA recent status assessment for polar bears published by Environment Canada inMay201426 showed only two subpopulations are lsquolikely decliningrsquo down from four listedby the PBSG as declining in 2013 and seven in 2010 (Figure 2)27 Baffin Bay whichearned its lsquolikely decliningrsquo status due to suspicions of overharvesting (not sea ice de-cline) was reported in 2017 to be likely stable28 Kane Basin assessed as lsquodecliningrsquoin 2010 and 2013 (but lsquodata deficientrsquo in 2014) was reported in 2017 to be lsquostablersquo or

1

0

5

10

15

20

25

30

0

5

10

15

20

25

30

1950 1960 1970 1980 1990 2000 2010

1950 1960 1970 1980 1990 2000 2010

(a) Official estimate

(b) Unofficial estimate

Figure 1 Official estimates of polar bear numbersUpper graph uses totals reported in PBSG status tables (to 2013) with minmax lowergraph uses the same figures but adds back in the so-called lsquoinaccuratersquo estimates

dropped between 2005 and 2013 (in 2014 the PBSG finally did the same)25 The 1960figure is a ballpark estimate Further detail can be found at my website18 and Crockford

20172

2

lsquolikely increasingrsquo28 (but see Section 10) This leaves only the Southern Beaufort bearpopulation as lsquolikely decliningrsquo and even this is a highly questionable assessment (seeSection 7) Note also that the number of subpopulation considered lsquodata deficientrsquo(Figure 2 areas in brown) has been reduced from nine in 2014 to six in 2017 threebear populations (Barents Sea Kara Sea and Kane Basin) have recently been surveyedand now have population estimates showing probable increases

For example a first-ever Kara Sea population estimate completed in late 2014potentially adds another 3200 or so bears to the global total29 This estimate (range2700ndash3500) derivedbyRussianbiologists was added to theofficial global countpub-lished in 2015 by the IUCN Red List21 A former ball-park estimate was about 200018

suggesting an increase may have taken place

Figure 2 Global polar bear population status assessment even better than thisFigures from the IUCN Polar Bear Specialist Group assessment (2013) and EnvironmentCanada (May 2014)30 Brown data deficient red declining yellow likely decline lightblue likely stable dark blue stable light green likely increase dark green increase

More recent surveys show BB BS KB and KS are stable or likely increasing2

3

3 Abrupt summer sea ice decline has not affectedpolar bear numbers as predicted

Arctic sea ice has declined since satellite records began in 1979 but polar bears haveso far adjusted well to this change especially to the sudden decline to reduced sum-mer sea ice levels that have been the norm since 2007 The degree of abrupt dropin summer sea ice that occurred in 2007 was not predicted by experts to occur untilmid-century However the predicted decimation of polar bears worldwide expectedunder mid-century conditions (Figure 3)31 ndash which entailed a loss of 23 of the globaltotal (to only about 6660ndash8325 bears) as well as the total extermination of 10 entiresubpopulations ndash not only failed to occur it did not come even close to happening32

If the experts had been right back in 2007 there would be no polar bears at all inthe Southern Beaufort or Western Hudson Bay this year33 There is also evidence thatless summer ice in the Central Canadian Arctic has already been beneficial for polarbears34 an advantage not expected until later this century This is due in part to thefact that less summer ice is good for ringed seals - on which polar bears prey ndash whichfeed primarily during the ice-free season (see Section 5) and which do best with first-year ice cover during the spring birthing and mating seasons

(a) (b)

Figure 3 Predicted sea ice changes versus outturn(a) Predictions based on 2004 data for 2020 (light grey) 2050 (mid grey) and 2080(dark grey) These were used in 2007 to predict a 66 decline in global polar bearnumbers (b) Situation as at 10 September 2012 an example of the sea ice extent

experienced in since 200735 See Crockford 2017 for details2

4

4 Chukchi Sea population is thrivingThe results of a new study published in 2013 were a direct contradiction of the re-peatedmessage that recent large sea-ice declines in late summer hadput these bearsin peril36 The paper showed that Chukchi polar bears are doingbetter than theywerein the 1980s37 and better than any others except the bears of Foxe Basin (northernHudson Bay) who are doing exceptionally well38

There is still no official population estimate for the Chukchi Sea the population isofficially listed as zero but was previously estimated at about 2000 individuals How-ever it appears that record-breaking sea-ice levels in September 2007 the lowestsince 1979 had no discernible effect on Chukchi Sea polar bears39 as confirmed byresearch up to 2016240 As a result the status of this population was upgraded fromlsquodecliningrsquo to lsquodata deficientrsquo by the PBSG in 201341 Despite the gloomy predictions alonger-than-average ice-freeperiodhas actually beengood forChukchi polar bears42

5 More preymeans healthier polar bearsThe reason Chukchi Sea polar bears did so well with an extended open-water sea-son was because ringed seals their primary prey do most of their feeding in ice-freesummer waters More fat seals mean more fat seal pups the following spring for po-lar bears A recent study found that in recent years with extensive September sea-iceminimums the summer feedingperiod for sealswas extendedand theybecameextrafat43 This meant that some seals provided a more energy-rich food source for polarbears over the following fall and winter an immediate benefit to the bears In addi-tion well-fed female ringed seals produced fat healthy pups the next spring whichmeant more food for polar bears when they needed it the most

Between 2008 and 2011 both ringed seals and polar bears did better than eitherhad done in the 1980s when summer sea ice coverage was more extensive Oddlyin March 2013 less than six months after ringed seals were placed on the Americanlist of species lsquothreatenedrsquo with extinction44 ringed seal biologists were reporting totheir peers that the results of their Chukchi Sea research contradicted their dire pre-dictions45 Surprisingly to them less summer sea ice was better for ringed seals notworse In July 2014 a judge decreed that the 2012 decision to list bearded seals inAlaska as lsquothreatenedrsquo was deficient and that there were no near-term threats Thejudge called it lsquoan abuse of discretionrsquo46

The USA stands out as the only nation that insists that Arctic seals have been (orwill be shortly) harmed by recent declines in summer sea ice47 which made it all themore surprising that in September 2017 the US Fish andWildlife Service announcedit would not pursue a plan to list Pacific walrus as lsquothreatenedrsquo with extinction underthe Endangered Species Act48 Their experts concluded there was no evidence of on-going harm or an imminent threat to walrus survival

5

6 Polar bears are adaptablePolar bears have been shown to move from areas with unsuitable ice to areas withbetter ice conditions even over the short term This is strong evidence of their abilityto adapt to changing sea ice Recently it was noted that a number of bears from theBarents Seawhere sea-ice coverage is strongly influencedbyvariations in theAtlanticMultidecadal Oscillation49 moved to the islands of the Franz Josef Land archipelagoin the Kara Sea where there has beenmore predictable ice cover50 This is just one ex-ample of polar bear flexibility A past example was the movement of Southern Beau-fort bears into the Chukchi Sea during the catastrophic 1974ndash1976 episode of thickspring ice in the Eastern Beaufort Flexibility in choosing maternity dens (onshorevs sea ice) as well as variability in feeding areas (nearshore vs offshore)51 give polarbears the resilience they need to survive as a species

7 Southern Beaufort numbers have reboundedAccording to a preliminary US Fish amp Wildlife Service survey Southern Beaufort bearnumberswerehigher in the fall of 2012 than theyhadbeen in theprevious tenyears52

indicating a recovery from the dramatic decline (25ndash50) that occurred between2004 and 2006 because of the effects of thick spring sea ice53 For unknown rea-sons the newly-developed models used to estimate Southern Beaufort populationsize used only data up until 2010 even though mark-recapture data up until 2012were available54 This is known because the data was used for another study seeSection 8 The failure of thick spring ice conditions to recur in recent years and theearly formation and expansion of spring polynyas in the eastern Beaufort have likelybeenbeneficial for polar bears and seals55 resulting in the rare sighting of at least oneset of healthy triplet cubs in 201656

8 Barents Sea numbers have increasedThe Svalbard portion of the Barents Sea subpopulation was surveyed in 2015 andwas initially reported to have increased by 42 over the count performed in 200457

The just-publishedpaper confirms that a 42 increase in abundance indeedoccurred(685 bears in 2004 versus 973 bears in 2015)58 However due to the large uncertainty(broad error ranges) in the estimates involved even a 42 increase was not statis-tically significant This point was strongly emphasized by the PBSG59 in their recentstatus update for the Barents Sea

Becauseof theoverlapping confidence intervals it cannot be concluded that theBS subpopulation has grown60

The authors of the Svalbard survey however had this to say

6

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

Executive summary1 Polar bears are still a conservation success story there are more polar bears

now than there were 40 years ago

2 Fewer populations are in decline than in 2010 (only one officially) and only sixare data deficient (down from nine)

3 Abrupt summer sea ice decline has not affected polar bear numbers as pre-dicted even though sea ice levels dropped to mid-century levels in 2007 theexpected decimation of polar bears failed to occur

4 The Chukchi Sea population is thriving despite a pronounced lengthening ofthe ice-free season since 2007

5 Less sea ice in the summer in the Chukchi Sea has meant a healthy prey basefor polar bears because ringed seals feed primarily in the ice-free season

6 Polar bears have shown themselves to be adaptable to changing ice conditionsin several regions

7 Southern Beaufort numbers have rebounded since the last survey count

8 Barents Sea numbers have probably increased since 2005 and have definitelynot declined despite much less sea ice cover

9 There is no evidence that record-low summer sea ice in 2012 had a harmfuleffect on Southern Beaufort bear numbers

10 Other species are being negatively impacted by high polar bear numbers es-pecially nesting sea birds and ducks

11 Western Hudson Bay population numbers have been stable since 2004 despitewhat scientists are telling the media

12 Hudson Bay sea ice has not changed since about 1999 the breakup dates andfreeze-up dates are highly variable but the ice-free period was not any longerin 2015 than it was in 2004 However this fall freeze-up is shaping up to be theearliest in decades

13 Problem bears in Churchill are not lean or starving

14 Churchill Manitoba had the most problem bears in 1983 and 2016 which werelate freeze-up years but many of the incidents in 2016 can be attributed to in-creased vigilance on the part of patrol officers after an attack in 2013

15 There have been only marginal sea-ice declines during the feeding period inspring when polar bears need sea ice the most

16 The is no evidence that subsistence hunting is affecting bear populations

17 Stressful research methods have been curtailed in much of Canada

ix

18 There have been no reports of polar bear cannibalism since 2011

19 Polar bears appear unaffected by pollution studies suggest only that harm istheoretically possible not that it has happened

20 Polar bears have survived past warm periods which is evidence they have theability to survive future warm periods

Conclusion

bull Polar bears are thriving they are not currently threatened with extinction

bull Tens of thousands of polar bears did not die as a result of more than a decadeof low summer sea ice as was predicted

bull Polar bears donrsquot need sea ice in late summerearly fall as long as they are well-fed in the spring

x

IntroductionJust in time for Polar Bears Internationalrsquos self-proclaimed9 fall Polar Bear Week (5ndash11November 2017)10 here is a new resource for cooling the polar bear spin Irsquove up-dated my 2015 summary of reasons not to worry about polar bears which is nowmore than two years old11 In this new version you will find links to supporting in-formation including published papers and fully referenced blog posts of mine thatprovide backgroundmaps andbibliographies although someof themost importantgraphs andmaps have been reproduced here I hope you find it a useful resource forrefuting the pessimism1213 and prophecies of catastrophe14 about the future of po-lar bears Please feel free to share it As global leaders meet in Bonn for COP23 (6ndash17November 2017)15 itrsquos time to celebrate the proven resilience of polar bears to theirever-changing Arctic environment

1 A conservation success storyPolar bears are still a conservation success story16 With the estimated global popu-lation almost certainly greater than 2800017 we can say for sure that there are morepolarbearsnowthan therewere40years ago (Figure1)18 Sadly althoughcompletinga global survey was one of the primary objectives of the Polar Bear Specialist Group(PBSG) at its inception 49 years ago it has so far been unable to do so because at leastfour subpopulations have never been counted The PBSG global estimate was listedin July 2014 as lsquoapproximately 25000rsquo bears19 This number has not been revised20

even though the estimate PBSG members provided the International Union for theConservation of Nature (IUCN) for its 2015 assessment was 22000ndash31000 or about2600021 Surveys completed or published since bring the total higher still2

Even with the lack of precision inherent in these estimates global numbers arestill too high to qualify the polar bear as lsquovulnerablersquo to or lsquothreatenedrsquo with extinc-tion based on current population levels22 Polar bears today are also well distributedthroughout their available habitat (winter sea ice)23 which is a recognized charac-teristic of a healthy species All concerns expressed regarding polar bear survival areabout the future24

2 Fewer populations in declineA recent status assessment for polar bears published by Environment Canada inMay201426 showed only two subpopulations are lsquolikely decliningrsquo down from four listedby the PBSG as declining in 2013 and seven in 2010 (Figure 2)27 Baffin Bay whichearned its lsquolikely decliningrsquo status due to suspicions of overharvesting (not sea ice de-cline) was reported in 2017 to be likely stable28 Kane Basin assessed as lsquodecliningrsquoin 2010 and 2013 (but lsquodata deficientrsquo in 2014) was reported in 2017 to be lsquostablersquo or

1

0

5

10

15

20

25

30

0

5

10

15

20

25

30

1950 1960 1970 1980 1990 2000 2010

1950 1960 1970 1980 1990 2000 2010

(a) Official estimate

(b) Unofficial estimate

Figure 1 Official estimates of polar bear numbersUpper graph uses totals reported in PBSG status tables (to 2013) with minmax lowergraph uses the same figures but adds back in the so-called lsquoinaccuratersquo estimates

dropped between 2005 and 2013 (in 2014 the PBSG finally did the same)25 The 1960figure is a ballpark estimate Further detail can be found at my website18 and Crockford

20172

2

lsquolikely increasingrsquo28 (but see Section 10) This leaves only the Southern Beaufort bearpopulation as lsquolikely decliningrsquo and even this is a highly questionable assessment (seeSection 7) Note also that the number of subpopulation considered lsquodata deficientrsquo(Figure 2 areas in brown) has been reduced from nine in 2014 to six in 2017 threebear populations (Barents Sea Kara Sea and Kane Basin) have recently been surveyedand now have population estimates showing probable increases

For example a first-ever Kara Sea population estimate completed in late 2014potentially adds another 3200 or so bears to the global total29 This estimate (range2700ndash3500) derivedbyRussianbiologists was added to theofficial global countpub-lished in 2015 by the IUCN Red List21 A former ball-park estimate was about 200018

suggesting an increase may have taken place

Figure 2 Global polar bear population status assessment even better than thisFigures from the IUCN Polar Bear Specialist Group assessment (2013) and EnvironmentCanada (May 2014)30 Brown data deficient red declining yellow likely decline lightblue likely stable dark blue stable light green likely increase dark green increase

More recent surveys show BB BS KB and KS are stable or likely increasing2

3

3 Abrupt summer sea ice decline has not affectedpolar bear numbers as predicted

Arctic sea ice has declined since satellite records began in 1979 but polar bears haveso far adjusted well to this change especially to the sudden decline to reduced sum-mer sea ice levels that have been the norm since 2007 The degree of abrupt dropin summer sea ice that occurred in 2007 was not predicted by experts to occur untilmid-century However the predicted decimation of polar bears worldwide expectedunder mid-century conditions (Figure 3)31 ndash which entailed a loss of 23 of the globaltotal (to only about 6660ndash8325 bears) as well as the total extermination of 10 entiresubpopulations ndash not only failed to occur it did not come even close to happening32

If the experts had been right back in 2007 there would be no polar bears at all inthe Southern Beaufort or Western Hudson Bay this year33 There is also evidence thatless summer ice in the Central Canadian Arctic has already been beneficial for polarbears34 an advantage not expected until later this century This is due in part to thefact that less summer ice is good for ringed seals - on which polar bears prey ndash whichfeed primarily during the ice-free season (see Section 5) and which do best with first-year ice cover during the spring birthing and mating seasons

(a) (b)

Figure 3 Predicted sea ice changes versus outturn(a) Predictions based on 2004 data for 2020 (light grey) 2050 (mid grey) and 2080(dark grey) These were used in 2007 to predict a 66 decline in global polar bearnumbers (b) Situation as at 10 September 2012 an example of the sea ice extent

experienced in since 200735 See Crockford 2017 for details2

4

4 Chukchi Sea population is thrivingThe results of a new study published in 2013 were a direct contradiction of the re-peatedmessage that recent large sea-ice declines in late summer hadput these bearsin peril36 The paper showed that Chukchi polar bears are doingbetter than theywerein the 1980s37 and better than any others except the bears of Foxe Basin (northernHudson Bay) who are doing exceptionally well38

There is still no official population estimate for the Chukchi Sea the population isofficially listed as zero but was previously estimated at about 2000 individuals How-ever it appears that record-breaking sea-ice levels in September 2007 the lowestsince 1979 had no discernible effect on Chukchi Sea polar bears39 as confirmed byresearch up to 2016240 As a result the status of this population was upgraded fromlsquodecliningrsquo to lsquodata deficientrsquo by the PBSG in 201341 Despite the gloomy predictions alonger-than-average ice-freeperiodhas actually beengood forChukchi polar bears42

5 More preymeans healthier polar bearsThe reason Chukchi Sea polar bears did so well with an extended open-water sea-son was because ringed seals their primary prey do most of their feeding in ice-freesummer waters More fat seals mean more fat seal pups the following spring for po-lar bears A recent study found that in recent years with extensive September sea-iceminimums the summer feedingperiod for sealswas extendedand theybecameextrafat43 This meant that some seals provided a more energy-rich food source for polarbears over the following fall and winter an immediate benefit to the bears In addi-tion well-fed female ringed seals produced fat healthy pups the next spring whichmeant more food for polar bears when they needed it the most

Between 2008 and 2011 both ringed seals and polar bears did better than eitherhad done in the 1980s when summer sea ice coverage was more extensive Oddlyin March 2013 less than six months after ringed seals were placed on the Americanlist of species lsquothreatenedrsquo with extinction44 ringed seal biologists were reporting totheir peers that the results of their Chukchi Sea research contradicted their dire pre-dictions45 Surprisingly to them less summer sea ice was better for ringed seals notworse In July 2014 a judge decreed that the 2012 decision to list bearded seals inAlaska as lsquothreatenedrsquo was deficient and that there were no near-term threats Thejudge called it lsquoan abuse of discretionrsquo46

The USA stands out as the only nation that insists that Arctic seals have been (orwill be shortly) harmed by recent declines in summer sea ice47 which made it all themore surprising that in September 2017 the US Fish andWildlife Service announcedit would not pursue a plan to list Pacific walrus as lsquothreatenedrsquo with extinction underthe Endangered Species Act48 Their experts concluded there was no evidence of on-going harm or an imminent threat to walrus survival

5

6 Polar bears are adaptablePolar bears have been shown to move from areas with unsuitable ice to areas withbetter ice conditions even over the short term This is strong evidence of their abilityto adapt to changing sea ice Recently it was noted that a number of bears from theBarents Seawhere sea-ice coverage is strongly influencedbyvariations in theAtlanticMultidecadal Oscillation49 moved to the islands of the Franz Josef Land archipelagoin the Kara Sea where there has beenmore predictable ice cover50 This is just one ex-ample of polar bear flexibility A past example was the movement of Southern Beau-fort bears into the Chukchi Sea during the catastrophic 1974ndash1976 episode of thickspring ice in the Eastern Beaufort Flexibility in choosing maternity dens (onshorevs sea ice) as well as variability in feeding areas (nearshore vs offshore)51 give polarbears the resilience they need to survive as a species

7 Southern Beaufort numbers have reboundedAccording to a preliminary US Fish amp Wildlife Service survey Southern Beaufort bearnumberswerehigher in the fall of 2012 than theyhadbeen in theprevious tenyears52

indicating a recovery from the dramatic decline (25ndash50) that occurred between2004 and 2006 because of the effects of thick spring sea ice53 For unknown rea-sons the newly-developed models used to estimate Southern Beaufort populationsize used only data up until 2010 even though mark-recapture data up until 2012were available54 This is known because the data was used for another study seeSection 8 The failure of thick spring ice conditions to recur in recent years and theearly formation and expansion of spring polynyas in the eastern Beaufort have likelybeenbeneficial for polar bears and seals55 resulting in the rare sighting of at least oneset of healthy triplet cubs in 201656

8 Barents Sea numbers have increasedThe Svalbard portion of the Barents Sea subpopulation was surveyed in 2015 andwas initially reported to have increased by 42 over the count performed in 200457

The just-publishedpaper confirms that a 42 increase in abundance indeedoccurred(685 bears in 2004 versus 973 bears in 2015)58 However due to the large uncertainty(broad error ranges) in the estimates involved even a 42 increase was not statis-tically significant This point was strongly emphasized by the PBSG59 in their recentstatus update for the Barents Sea

Becauseof theoverlapping confidence intervals it cannot be concluded that theBS subpopulation has grown60

The authors of the Svalbard survey however had this to say

6

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

18 There have been no reports of polar bear cannibalism since 2011

19 Polar bears appear unaffected by pollution studies suggest only that harm istheoretically possible not that it has happened

20 Polar bears have survived past warm periods which is evidence they have theability to survive future warm periods

Conclusion

bull Polar bears are thriving they are not currently threatened with extinction

bull Tens of thousands of polar bears did not die as a result of more than a decadeof low summer sea ice as was predicted

bull Polar bears donrsquot need sea ice in late summerearly fall as long as they are well-fed in the spring

x

IntroductionJust in time for Polar Bears Internationalrsquos self-proclaimed9 fall Polar Bear Week (5ndash11November 2017)10 here is a new resource for cooling the polar bear spin Irsquove up-dated my 2015 summary of reasons not to worry about polar bears which is nowmore than two years old11 In this new version you will find links to supporting in-formation including published papers and fully referenced blog posts of mine thatprovide backgroundmaps andbibliographies although someof themost importantgraphs andmaps have been reproduced here I hope you find it a useful resource forrefuting the pessimism1213 and prophecies of catastrophe14 about the future of po-lar bears Please feel free to share it As global leaders meet in Bonn for COP23 (6ndash17November 2017)15 itrsquos time to celebrate the proven resilience of polar bears to theirever-changing Arctic environment

1 A conservation success storyPolar bears are still a conservation success story16 With the estimated global popu-lation almost certainly greater than 2800017 we can say for sure that there are morepolarbearsnowthan therewere40years ago (Figure1)18 Sadly althoughcompletinga global survey was one of the primary objectives of the Polar Bear Specialist Group(PBSG) at its inception 49 years ago it has so far been unable to do so because at leastfour subpopulations have never been counted The PBSG global estimate was listedin July 2014 as lsquoapproximately 25000rsquo bears19 This number has not been revised20

even though the estimate PBSG members provided the International Union for theConservation of Nature (IUCN) for its 2015 assessment was 22000ndash31000 or about2600021 Surveys completed or published since bring the total higher still2

Even with the lack of precision inherent in these estimates global numbers arestill too high to qualify the polar bear as lsquovulnerablersquo to or lsquothreatenedrsquo with extinc-tion based on current population levels22 Polar bears today are also well distributedthroughout their available habitat (winter sea ice)23 which is a recognized charac-teristic of a healthy species All concerns expressed regarding polar bear survival areabout the future24

2 Fewer populations in declineA recent status assessment for polar bears published by Environment Canada inMay201426 showed only two subpopulations are lsquolikely decliningrsquo down from four listedby the PBSG as declining in 2013 and seven in 2010 (Figure 2)27 Baffin Bay whichearned its lsquolikely decliningrsquo status due to suspicions of overharvesting (not sea ice de-cline) was reported in 2017 to be likely stable28 Kane Basin assessed as lsquodecliningrsquoin 2010 and 2013 (but lsquodata deficientrsquo in 2014) was reported in 2017 to be lsquostablersquo or

1

0

5

10

15

20

25

30

0

5

10

15

20

25

30

1950 1960 1970 1980 1990 2000 2010

1950 1960 1970 1980 1990 2000 2010

(a) Official estimate

(b) Unofficial estimate

Figure 1 Official estimates of polar bear numbersUpper graph uses totals reported in PBSG status tables (to 2013) with minmax lowergraph uses the same figures but adds back in the so-called lsquoinaccuratersquo estimates

dropped between 2005 and 2013 (in 2014 the PBSG finally did the same)25 The 1960figure is a ballpark estimate Further detail can be found at my website18 and Crockford

20172

2

lsquolikely increasingrsquo28 (but see Section 10) This leaves only the Southern Beaufort bearpopulation as lsquolikely decliningrsquo and even this is a highly questionable assessment (seeSection 7) Note also that the number of subpopulation considered lsquodata deficientrsquo(Figure 2 areas in brown) has been reduced from nine in 2014 to six in 2017 threebear populations (Barents Sea Kara Sea and Kane Basin) have recently been surveyedand now have population estimates showing probable increases

For example a first-ever Kara Sea population estimate completed in late 2014potentially adds another 3200 or so bears to the global total29 This estimate (range2700ndash3500) derivedbyRussianbiologists was added to theofficial global countpub-lished in 2015 by the IUCN Red List21 A former ball-park estimate was about 200018

suggesting an increase may have taken place

Figure 2 Global polar bear population status assessment even better than thisFigures from the IUCN Polar Bear Specialist Group assessment (2013) and EnvironmentCanada (May 2014)30 Brown data deficient red declining yellow likely decline lightblue likely stable dark blue stable light green likely increase dark green increase

More recent surveys show BB BS KB and KS are stable or likely increasing2

3

3 Abrupt summer sea ice decline has not affectedpolar bear numbers as predicted

Arctic sea ice has declined since satellite records began in 1979 but polar bears haveso far adjusted well to this change especially to the sudden decline to reduced sum-mer sea ice levels that have been the norm since 2007 The degree of abrupt dropin summer sea ice that occurred in 2007 was not predicted by experts to occur untilmid-century However the predicted decimation of polar bears worldwide expectedunder mid-century conditions (Figure 3)31 ndash which entailed a loss of 23 of the globaltotal (to only about 6660ndash8325 bears) as well as the total extermination of 10 entiresubpopulations ndash not only failed to occur it did not come even close to happening32

If the experts had been right back in 2007 there would be no polar bears at all inthe Southern Beaufort or Western Hudson Bay this year33 There is also evidence thatless summer ice in the Central Canadian Arctic has already been beneficial for polarbears34 an advantage not expected until later this century This is due in part to thefact that less summer ice is good for ringed seals - on which polar bears prey ndash whichfeed primarily during the ice-free season (see Section 5) and which do best with first-year ice cover during the spring birthing and mating seasons

(a) (b)

Figure 3 Predicted sea ice changes versus outturn(a) Predictions based on 2004 data for 2020 (light grey) 2050 (mid grey) and 2080(dark grey) These were used in 2007 to predict a 66 decline in global polar bearnumbers (b) Situation as at 10 September 2012 an example of the sea ice extent

experienced in since 200735 See Crockford 2017 for details2

4

4 Chukchi Sea population is thrivingThe results of a new study published in 2013 were a direct contradiction of the re-peatedmessage that recent large sea-ice declines in late summer hadput these bearsin peril36 The paper showed that Chukchi polar bears are doingbetter than theywerein the 1980s37 and better than any others except the bears of Foxe Basin (northernHudson Bay) who are doing exceptionally well38

There is still no official population estimate for the Chukchi Sea the population isofficially listed as zero but was previously estimated at about 2000 individuals How-ever it appears that record-breaking sea-ice levels in September 2007 the lowestsince 1979 had no discernible effect on Chukchi Sea polar bears39 as confirmed byresearch up to 2016240 As a result the status of this population was upgraded fromlsquodecliningrsquo to lsquodata deficientrsquo by the PBSG in 201341 Despite the gloomy predictions alonger-than-average ice-freeperiodhas actually beengood forChukchi polar bears42

5 More preymeans healthier polar bearsThe reason Chukchi Sea polar bears did so well with an extended open-water sea-son was because ringed seals their primary prey do most of their feeding in ice-freesummer waters More fat seals mean more fat seal pups the following spring for po-lar bears A recent study found that in recent years with extensive September sea-iceminimums the summer feedingperiod for sealswas extendedand theybecameextrafat43 This meant that some seals provided a more energy-rich food source for polarbears over the following fall and winter an immediate benefit to the bears In addi-tion well-fed female ringed seals produced fat healthy pups the next spring whichmeant more food for polar bears when they needed it the most

Between 2008 and 2011 both ringed seals and polar bears did better than eitherhad done in the 1980s when summer sea ice coverage was more extensive Oddlyin March 2013 less than six months after ringed seals were placed on the Americanlist of species lsquothreatenedrsquo with extinction44 ringed seal biologists were reporting totheir peers that the results of their Chukchi Sea research contradicted their dire pre-dictions45 Surprisingly to them less summer sea ice was better for ringed seals notworse In July 2014 a judge decreed that the 2012 decision to list bearded seals inAlaska as lsquothreatenedrsquo was deficient and that there were no near-term threats Thejudge called it lsquoan abuse of discretionrsquo46

The USA stands out as the only nation that insists that Arctic seals have been (orwill be shortly) harmed by recent declines in summer sea ice47 which made it all themore surprising that in September 2017 the US Fish andWildlife Service announcedit would not pursue a plan to list Pacific walrus as lsquothreatenedrsquo with extinction underthe Endangered Species Act48 Their experts concluded there was no evidence of on-going harm or an imminent threat to walrus survival

5

6 Polar bears are adaptablePolar bears have been shown to move from areas with unsuitable ice to areas withbetter ice conditions even over the short term This is strong evidence of their abilityto adapt to changing sea ice Recently it was noted that a number of bears from theBarents Seawhere sea-ice coverage is strongly influencedbyvariations in theAtlanticMultidecadal Oscillation49 moved to the islands of the Franz Josef Land archipelagoin the Kara Sea where there has beenmore predictable ice cover50 This is just one ex-ample of polar bear flexibility A past example was the movement of Southern Beau-fort bears into the Chukchi Sea during the catastrophic 1974ndash1976 episode of thickspring ice in the Eastern Beaufort Flexibility in choosing maternity dens (onshorevs sea ice) as well as variability in feeding areas (nearshore vs offshore)51 give polarbears the resilience they need to survive as a species

7 Southern Beaufort numbers have reboundedAccording to a preliminary US Fish amp Wildlife Service survey Southern Beaufort bearnumberswerehigher in the fall of 2012 than theyhadbeen in theprevious tenyears52

indicating a recovery from the dramatic decline (25ndash50) that occurred between2004 and 2006 because of the effects of thick spring sea ice53 For unknown rea-sons the newly-developed models used to estimate Southern Beaufort populationsize used only data up until 2010 even though mark-recapture data up until 2012were available54 This is known because the data was used for another study seeSection 8 The failure of thick spring ice conditions to recur in recent years and theearly formation and expansion of spring polynyas in the eastern Beaufort have likelybeenbeneficial for polar bears and seals55 resulting in the rare sighting of at least oneset of healthy triplet cubs in 201656

8 Barents Sea numbers have increasedThe Svalbard portion of the Barents Sea subpopulation was surveyed in 2015 andwas initially reported to have increased by 42 over the count performed in 200457

The just-publishedpaper confirms that a 42 increase in abundance indeedoccurred(685 bears in 2004 versus 973 bears in 2015)58 However due to the large uncertainty(broad error ranges) in the estimates involved even a 42 increase was not statis-tically significant This point was strongly emphasized by the PBSG59 in their recentstatus update for the Barents Sea

Becauseof theoverlapping confidence intervals it cannot be concluded that theBS subpopulation has grown60

The authors of the Svalbard survey however had this to say

6

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

IntroductionJust in time for Polar Bears Internationalrsquos self-proclaimed9 fall Polar Bear Week (5ndash11November 2017)10 here is a new resource for cooling the polar bear spin Irsquove up-dated my 2015 summary of reasons not to worry about polar bears which is nowmore than two years old11 In this new version you will find links to supporting in-formation including published papers and fully referenced blog posts of mine thatprovide backgroundmaps andbibliographies although someof themost importantgraphs andmaps have been reproduced here I hope you find it a useful resource forrefuting the pessimism1213 and prophecies of catastrophe14 about the future of po-lar bears Please feel free to share it As global leaders meet in Bonn for COP23 (6ndash17November 2017)15 itrsquos time to celebrate the proven resilience of polar bears to theirever-changing Arctic environment

1 A conservation success storyPolar bears are still a conservation success story16 With the estimated global popu-lation almost certainly greater than 2800017 we can say for sure that there are morepolarbearsnowthan therewere40years ago (Figure1)18 Sadly althoughcompletinga global survey was one of the primary objectives of the Polar Bear Specialist Group(PBSG) at its inception 49 years ago it has so far been unable to do so because at leastfour subpopulations have never been counted The PBSG global estimate was listedin July 2014 as lsquoapproximately 25000rsquo bears19 This number has not been revised20

even though the estimate PBSG members provided the International Union for theConservation of Nature (IUCN) for its 2015 assessment was 22000ndash31000 or about2600021 Surveys completed or published since bring the total higher still2

Even with the lack of precision inherent in these estimates global numbers arestill too high to qualify the polar bear as lsquovulnerablersquo to or lsquothreatenedrsquo with extinc-tion based on current population levels22 Polar bears today are also well distributedthroughout their available habitat (winter sea ice)23 which is a recognized charac-teristic of a healthy species All concerns expressed regarding polar bear survival areabout the future24

2 Fewer populations in declineA recent status assessment for polar bears published by Environment Canada inMay201426 showed only two subpopulations are lsquolikely decliningrsquo down from four listedby the PBSG as declining in 2013 and seven in 2010 (Figure 2)27 Baffin Bay whichearned its lsquolikely decliningrsquo status due to suspicions of overharvesting (not sea ice de-cline) was reported in 2017 to be likely stable28 Kane Basin assessed as lsquodecliningrsquoin 2010 and 2013 (but lsquodata deficientrsquo in 2014) was reported in 2017 to be lsquostablersquo or

1

0

5

10

15

20

25

30

0

5

10

15

20

25

30

1950 1960 1970 1980 1990 2000 2010

1950 1960 1970 1980 1990 2000 2010

(a) Official estimate

(b) Unofficial estimate

Figure 1 Official estimates of polar bear numbersUpper graph uses totals reported in PBSG status tables (to 2013) with minmax lowergraph uses the same figures but adds back in the so-called lsquoinaccuratersquo estimates

dropped between 2005 and 2013 (in 2014 the PBSG finally did the same)25 The 1960figure is a ballpark estimate Further detail can be found at my website18 and Crockford

20172

2

lsquolikely increasingrsquo28 (but see Section 10) This leaves only the Southern Beaufort bearpopulation as lsquolikely decliningrsquo and even this is a highly questionable assessment (seeSection 7) Note also that the number of subpopulation considered lsquodata deficientrsquo(Figure 2 areas in brown) has been reduced from nine in 2014 to six in 2017 threebear populations (Barents Sea Kara Sea and Kane Basin) have recently been surveyedand now have population estimates showing probable increases

For example a first-ever Kara Sea population estimate completed in late 2014potentially adds another 3200 or so bears to the global total29 This estimate (range2700ndash3500) derivedbyRussianbiologists was added to theofficial global countpub-lished in 2015 by the IUCN Red List21 A former ball-park estimate was about 200018

suggesting an increase may have taken place

Figure 2 Global polar bear population status assessment even better than thisFigures from the IUCN Polar Bear Specialist Group assessment (2013) and EnvironmentCanada (May 2014)30 Brown data deficient red declining yellow likely decline lightblue likely stable dark blue stable light green likely increase dark green increase

More recent surveys show BB BS KB and KS are stable or likely increasing2

3

3 Abrupt summer sea ice decline has not affectedpolar bear numbers as predicted

Arctic sea ice has declined since satellite records began in 1979 but polar bears haveso far adjusted well to this change especially to the sudden decline to reduced sum-mer sea ice levels that have been the norm since 2007 The degree of abrupt dropin summer sea ice that occurred in 2007 was not predicted by experts to occur untilmid-century However the predicted decimation of polar bears worldwide expectedunder mid-century conditions (Figure 3)31 ndash which entailed a loss of 23 of the globaltotal (to only about 6660ndash8325 bears) as well as the total extermination of 10 entiresubpopulations ndash not only failed to occur it did not come even close to happening32

If the experts had been right back in 2007 there would be no polar bears at all inthe Southern Beaufort or Western Hudson Bay this year33 There is also evidence thatless summer ice in the Central Canadian Arctic has already been beneficial for polarbears34 an advantage not expected until later this century This is due in part to thefact that less summer ice is good for ringed seals - on which polar bears prey ndash whichfeed primarily during the ice-free season (see Section 5) and which do best with first-year ice cover during the spring birthing and mating seasons

(a) (b)

Figure 3 Predicted sea ice changes versus outturn(a) Predictions based on 2004 data for 2020 (light grey) 2050 (mid grey) and 2080(dark grey) These were used in 2007 to predict a 66 decline in global polar bearnumbers (b) Situation as at 10 September 2012 an example of the sea ice extent

experienced in since 200735 See Crockford 2017 for details2

4

4 Chukchi Sea population is thrivingThe results of a new study published in 2013 were a direct contradiction of the re-peatedmessage that recent large sea-ice declines in late summer hadput these bearsin peril36 The paper showed that Chukchi polar bears are doingbetter than theywerein the 1980s37 and better than any others except the bears of Foxe Basin (northernHudson Bay) who are doing exceptionally well38

There is still no official population estimate for the Chukchi Sea the population isofficially listed as zero but was previously estimated at about 2000 individuals How-ever it appears that record-breaking sea-ice levels in September 2007 the lowestsince 1979 had no discernible effect on Chukchi Sea polar bears39 as confirmed byresearch up to 2016240 As a result the status of this population was upgraded fromlsquodecliningrsquo to lsquodata deficientrsquo by the PBSG in 201341 Despite the gloomy predictions alonger-than-average ice-freeperiodhas actually beengood forChukchi polar bears42

5 More preymeans healthier polar bearsThe reason Chukchi Sea polar bears did so well with an extended open-water sea-son was because ringed seals their primary prey do most of their feeding in ice-freesummer waters More fat seals mean more fat seal pups the following spring for po-lar bears A recent study found that in recent years with extensive September sea-iceminimums the summer feedingperiod for sealswas extendedand theybecameextrafat43 This meant that some seals provided a more energy-rich food source for polarbears over the following fall and winter an immediate benefit to the bears In addi-tion well-fed female ringed seals produced fat healthy pups the next spring whichmeant more food for polar bears when they needed it the most

Between 2008 and 2011 both ringed seals and polar bears did better than eitherhad done in the 1980s when summer sea ice coverage was more extensive Oddlyin March 2013 less than six months after ringed seals were placed on the Americanlist of species lsquothreatenedrsquo with extinction44 ringed seal biologists were reporting totheir peers that the results of their Chukchi Sea research contradicted their dire pre-dictions45 Surprisingly to them less summer sea ice was better for ringed seals notworse In July 2014 a judge decreed that the 2012 decision to list bearded seals inAlaska as lsquothreatenedrsquo was deficient and that there were no near-term threats Thejudge called it lsquoan abuse of discretionrsquo46

The USA stands out as the only nation that insists that Arctic seals have been (orwill be shortly) harmed by recent declines in summer sea ice47 which made it all themore surprising that in September 2017 the US Fish andWildlife Service announcedit would not pursue a plan to list Pacific walrus as lsquothreatenedrsquo with extinction underthe Endangered Species Act48 Their experts concluded there was no evidence of on-going harm or an imminent threat to walrus survival

5

6 Polar bears are adaptablePolar bears have been shown to move from areas with unsuitable ice to areas withbetter ice conditions even over the short term This is strong evidence of their abilityto adapt to changing sea ice Recently it was noted that a number of bears from theBarents Seawhere sea-ice coverage is strongly influencedbyvariations in theAtlanticMultidecadal Oscillation49 moved to the islands of the Franz Josef Land archipelagoin the Kara Sea where there has beenmore predictable ice cover50 This is just one ex-ample of polar bear flexibility A past example was the movement of Southern Beau-fort bears into the Chukchi Sea during the catastrophic 1974ndash1976 episode of thickspring ice in the Eastern Beaufort Flexibility in choosing maternity dens (onshorevs sea ice) as well as variability in feeding areas (nearshore vs offshore)51 give polarbears the resilience they need to survive as a species

7 Southern Beaufort numbers have reboundedAccording to a preliminary US Fish amp Wildlife Service survey Southern Beaufort bearnumberswerehigher in the fall of 2012 than theyhadbeen in theprevious tenyears52

indicating a recovery from the dramatic decline (25ndash50) that occurred between2004 and 2006 because of the effects of thick spring sea ice53 For unknown rea-sons the newly-developed models used to estimate Southern Beaufort populationsize used only data up until 2010 even though mark-recapture data up until 2012were available54 This is known because the data was used for another study seeSection 8 The failure of thick spring ice conditions to recur in recent years and theearly formation and expansion of spring polynyas in the eastern Beaufort have likelybeenbeneficial for polar bears and seals55 resulting in the rare sighting of at least oneset of healthy triplet cubs in 201656

8 Barents Sea numbers have increasedThe Svalbard portion of the Barents Sea subpopulation was surveyed in 2015 andwas initially reported to have increased by 42 over the count performed in 200457

The just-publishedpaper confirms that a 42 increase in abundance indeedoccurred(685 bears in 2004 versus 973 bears in 2015)58 However due to the large uncertainty(broad error ranges) in the estimates involved even a 42 increase was not statis-tically significant This point was strongly emphasized by the PBSG59 in their recentstatus update for the Barents Sea

Becauseof theoverlapping confidence intervals it cannot be concluded that theBS subpopulation has grown60

The authors of the Svalbard survey however had this to say

6

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

0

5

10

15

20

25

30

0

5

10

15

20

25

30

1950 1960 1970 1980 1990 2000 2010

1950 1960 1970 1980 1990 2000 2010

(a) Official estimate

(b) Unofficial estimate

Figure 1 Official estimates of polar bear numbersUpper graph uses totals reported in PBSG status tables (to 2013) with minmax lowergraph uses the same figures but adds back in the so-called lsquoinaccuratersquo estimates

dropped between 2005 and 2013 (in 2014 the PBSG finally did the same)25 The 1960figure is a ballpark estimate Further detail can be found at my website18 and Crockford

20172

2

lsquolikely increasingrsquo28 (but see Section 10) This leaves only the Southern Beaufort bearpopulation as lsquolikely decliningrsquo and even this is a highly questionable assessment (seeSection 7) Note also that the number of subpopulation considered lsquodata deficientrsquo(Figure 2 areas in brown) has been reduced from nine in 2014 to six in 2017 threebear populations (Barents Sea Kara Sea and Kane Basin) have recently been surveyedand now have population estimates showing probable increases

For example a first-ever Kara Sea population estimate completed in late 2014potentially adds another 3200 or so bears to the global total29 This estimate (range2700ndash3500) derivedbyRussianbiologists was added to theofficial global countpub-lished in 2015 by the IUCN Red List21 A former ball-park estimate was about 200018

suggesting an increase may have taken place

Figure 2 Global polar bear population status assessment even better than thisFigures from the IUCN Polar Bear Specialist Group assessment (2013) and EnvironmentCanada (May 2014)30 Brown data deficient red declining yellow likely decline lightblue likely stable dark blue stable light green likely increase dark green increase

More recent surveys show BB BS KB and KS are stable or likely increasing2

3

3 Abrupt summer sea ice decline has not affectedpolar bear numbers as predicted

Arctic sea ice has declined since satellite records began in 1979 but polar bears haveso far adjusted well to this change especially to the sudden decline to reduced sum-mer sea ice levels that have been the norm since 2007 The degree of abrupt dropin summer sea ice that occurred in 2007 was not predicted by experts to occur untilmid-century However the predicted decimation of polar bears worldwide expectedunder mid-century conditions (Figure 3)31 ndash which entailed a loss of 23 of the globaltotal (to only about 6660ndash8325 bears) as well as the total extermination of 10 entiresubpopulations ndash not only failed to occur it did not come even close to happening32

If the experts had been right back in 2007 there would be no polar bears at all inthe Southern Beaufort or Western Hudson Bay this year33 There is also evidence thatless summer ice in the Central Canadian Arctic has already been beneficial for polarbears34 an advantage not expected until later this century This is due in part to thefact that less summer ice is good for ringed seals - on which polar bears prey ndash whichfeed primarily during the ice-free season (see Section 5) and which do best with first-year ice cover during the spring birthing and mating seasons

(a) (b)

Figure 3 Predicted sea ice changes versus outturn(a) Predictions based on 2004 data for 2020 (light grey) 2050 (mid grey) and 2080(dark grey) These were used in 2007 to predict a 66 decline in global polar bearnumbers (b) Situation as at 10 September 2012 an example of the sea ice extent

experienced in since 200735 See Crockford 2017 for details2

4

4 Chukchi Sea population is thrivingThe results of a new study published in 2013 were a direct contradiction of the re-peatedmessage that recent large sea-ice declines in late summer hadput these bearsin peril36 The paper showed that Chukchi polar bears are doingbetter than theywerein the 1980s37 and better than any others except the bears of Foxe Basin (northernHudson Bay) who are doing exceptionally well38

There is still no official population estimate for the Chukchi Sea the population isofficially listed as zero but was previously estimated at about 2000 individuals How-ever it appears that record-breaking sea-ice levels in September 2007 the lowestsince 1979 had no discernible effect on Chukchi Sea polar bears39 as confirmed byresearch up to 2016240 As a result the status of this population was upgraded fromlsquodecliningrsquo to lsquodata deficientrsquo by the PBSG in 201341 Despite the gloomy predictions alonger-than-average ice-freeperiodhas actually beengood forChukchi polar bears42

5 More preymeans healthier polar bearsThe reason Chukchi Sea polar bears did so well with an extended open-water sea-son was because ringed seals their primary prey do most of their feeding in ice-freesummer waters More fat seals mean more fat seal pups the following spring for po-lar bears A recent study found that in recent years with extensive September sea-iceminimums the summer feedingperiod for sealswas extendedand theybecameextrafat43 This meant that some seals provided a more energy-rich food source for polarbears over the following fall and winter an immediate benefit to the bears In addi-tion well-fed female ringed seals produced fat healthy pups the next spring whichmeant more food for polar bears when they needed it the most

Between 2008 and 2011 both ringed seals and polar bears did better than eitherhad done in the 1980s when summer sea ice coverage was more extensive Oddlyin March 2013 less than six months after ringed seals were placed on the Americanlist of species lsquothreatenedrsquo with extinction44 ringed seal biologists were reporting totheir peers that the results of their Chukchi Sea research contradicted their dire pre-dictions45 Surprisingly to them less summer sea ice was better for ringed seals notworse In July 2014 a judge decreed that the 2012 decision to list bearded seals inAlaska as lsquothreatenedrsquo was deficient and that there were no near-term threats Thejudge called it lsquoan abuse of discretionrsquo46

The USA stands out as the only nation that insists that Arctic seals have been (orwill be shortly) harmed by recent declines in summer sea ice47 which made it all themore surprising that in September 2017 the US Fish andWildlife Service announcedit would not pursue a plan to list Pacific walrus as lsquothreatenedrsquo with extinction underthe Endangered Species Act48 Their experts concluded there was no evidence of on-going harm or an imminent threat to walrus survival

5

6 Polar bears are adaptablePolar bears have been shown to move from areas with unsuitable ice to areas withbetter ice conditions even over the short term This is strong evidence of their abilityto adapt to changing sea ice Recently it was noted that a number of bears from theBarents Seawhere sea-ice coverage is strongly influencedbyvariations in theAtlanticMultidecadal Oscillation49 moved to the islands of the Franz Josef Land archipelagoin the Kara Sea where there has beenmore predictable ice cover50 This is just one ex-ample of polar bear flexibility A past example was the movement of Southern Beau-fort bears into the Chukchi Sea during the catastrophic 1974ndash1976 episode of thickspring ice in the Eastern Beaufort Flexibility in choosing maternity dens (onshorevs sea ice) as well as variability in feeding areas (nearshore vs offshore)51 give polarbears the resilience they need to survive as a species

7 Southern Beaufort numbers have reboundedAccording to a preliminary US Fish amp Wildlife Service survey Southern Beaufort bearnumberswerehigher in the fall of 2012 than theyhadbeen in theprevious tenyears52

indicating a recovery from the dramatic decline (25ndash50) that occurred between2004 and 2006 because of the effects of thick spring sea ice53 For unknown rea-sons the newly-developed models used to estimate Southern Beaufort populationsize used only data up until 2010 even though mark-recapture data up until 2012were available54 This is known because the data was used for another study seeSection 8 The failure of thick spring ice conditions to recur in recent years and theearly formation and expansion of spring polynyas in the eastern Beaufort have likelybeenbeneficial for polar bears and seals55 resulting in the rare sighting of at least oneset of healthy triplet cubs in 201656

8 Barents Sea numbers have increasedThe Svalbard portion of the Barents Sea subpopulation was surveyed in 2015 andwas initially reported to have increased by 42 over the count performed in 200457

The just-publishedpaper confirms that a 42 increase in abundance indeedoccurred(685 bears in 2004 versus 973 bears in 2015)58 However due to the large uncertainty(broad error ranges) in the estimates involved even a 42 increase was not statis-tically significant This point was strongly emphasized by the PBSG59 in their recentstatus update for the Barents Sea

Becauseof theoverlapping confidence intervals it cannot be concluded that theBS subpopulation has grown60

The authors of the Svalbard survey however had this to say

6

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

lsquolikely increasingrsquo28 (but see Section 10) This leaves only the Southern Beaufort bearpopulation as lsquolikely decliningrsquo and even this is a highly questionable assessment (seeSection 7) Note also that the number of subpopulation considered lsquodata deficientrsquo(Figure 2 areas in brown) has been reduced from nine in 2014 to six in 2017 threebear populations (Barents Sea Kara Sea and Kane Basin) have recently been surveyedand now have population estimates showing probable increases

For example a first-ever Kara Sea population estimate completed in late 2014potentially adds another 3200 or so bears to the global total29 This estimate (range2700ndash3500) derivedbyRussianbiologists was added to theofficial global countpub-lished in 2015 by the IUCN Red List21 A former ball-park estimate was about 200018

suggesting an increase may have taken place

Figure 2 Global polar bear population status assessment even better than thisFigures from the IUCN Polar Bear Specialist Group assessment (2013) and EnvironmentCanada (May 2014)30 Brown data deficient red declining yellow likely decline lightblue likely stable dark blue stable light green likely increase dark green increase

More recent surveys show BB BS KB and KS are stable or likely increasing2

3

3 Abrupt summer sea ice decline has not affectedpolar bear numbers as predicted

Arctic sea ice has declined since satellite records began in 1979 but polar bears haveso far adjusted well to this change especially to the sudden decline to reduced sum-mer sea ice levels that have been the norm since 2007 The degree of abrupt dropin summer sea ice that occurred in 2007 was not predicted by experts to occur untilmid-century However the predicted decimation of polar bears worldwide expectedunder mid-century conditions (Figure 3)31 ndash which entailed a loss of 23 of the globaltotal (to only about 6660ndash8325 bears) as well as the total extermination of 10 entiresubpopulations ndash not only failed to occur it did not come even close to happening32

If the experts had been right back in 2007 there would be no polar bears at all inthe Southern Beaufort or Western Hudson Bay this year33 There is also evidence thatless summer ice in the Central Canadian Arctic has already been beneficial for polarbears34 an advantage not expected until later this century This is due in part to thefact that less summer ice is good for ringed seals - on which polar bears prey ndash whichfeed primarily during the ice-free season (see Section 5) and which do best with first-year ice cover during the spring birthing and mating seasons

(a) (b)

Figure 3 Predicted sea ice changes versus outturn(a) Predictions based on 2004 data for 2020 (light grey) 2050 (mid grey) and 2080(dark grey) These were used in 2007 to predict a 66 decline in global polar bearnumbers (b) Situation as at 10 September 2012 an example of the sea ice extent

experienced in since 200735 See Crockford 2017 for details2

4

4 Chukchi Sea population is thrivingThe results of a new study published in 2013 were a direct contradiction of the re-peatedmessage that recent large sea-ice declines in late summer hadput these bearsin peril36 The paper showed that Chukchi polar bears are doingbetter than theywerein the 1980s37 and better than any others except the bears of Foxe Basin (northernHudson Bay) who are doing exceptionally well38

There is still no official population estimate for the Chukchi Sea the population isofficially listed as zero but was previously estimated at about 2000 individuals How-ever it appears that record-breaking sea-ice levels in September 2007 the lowestsince 1979 had no discernible effect on Chukchi Sea polar bears39 as confirmed byresearch up to 2016240 As a result the status of this population was upgraded fromlsquodecliningrsquo to lsquodata deficientrsquo by the PBSG in 201341 Despite the gloomy predictions alonger-than-average ice-freeperiodhas actually beengood forChukchi polar bears42

5 More preymeans healthier polar bearsThe reason Chukchi Sea polar bears did so well with an extended open-water sea-son was because ringed seals their primary prey do most of their feeding in ice-freesummer waters More fat seals mean more fat seal pups the following spring for po-lar bears A recent study found that in recent years with extensive September sea-iceminimums the summer feedingperiod for sealswas extendedand theybecameextrafat43 This meant that some seals provided a more energy-rich food source for polarbears over the following fall and winter an immediate benefit to the bears In addi-tion well-fed female ringed seals produced fat healthy pups the next spring whichmeant more food for polar bears when they needed it the most

Between 2008 and 2011 both ringed seals and polar bears did better than eitherhad done in the 1980s when summer sea ice coverage was more extensive Oddlyin March 2013 less than six months after ringed seals were placed on the Americanlist of species lsquothreatenedrsquo with extinction44 ringed seal biologists were reporting totheir peers that the results of their Chukchi Sea research contradicted their dire pre-dictions45 Surprisingly to them less summer sea ice was better for ringed seals notworse In July 2014 a judge decreed that the 2012 decision to list bearded seals inAlaska as lsquothreatenedrsquo was deficient and that there were no near-term threats Thejudge called it lsquoan abuse of discretionrsquo46

The USA stands out as the only nation that insists that Arctic seals have been (orwill be shortly) harmed by recent declines in summer sea ice47 which made it all themore surprising that in September 2017 the US Fish andWildlife Service announcedit would not pursue a plan to list Pacific walrus as lsquothreatenedrsquo with extinction underthe Endangered Species Act48 Their experts concluded there was no evidence of on-going harm or an imminent threat to walrus survival

5

6 Polar bears are adaptablePolar bears have been shown to move from areas with unsuitable ice to areas withbetter ice conditions even over the short term This is strong evidence of their abilityto adapt to changing sea ice Recently it was noted that a number of bears from theBarents Seawhere sea-ice coverage is strongly influencedbyvariations in theAtlanticMultidecadal Oscillation49 moved to the islands of the Franz Josef Land archipelagoin the Kara Sea where there has beenmore predictable ice cover50 This is just one ex-ample of polar bear flexibility A past example was the movement of Southern Beau-fort bears into the Chukchi Sea during the catastrophic 1974ndash1976 episode of thickspring ice in the Eastern Beaufort Flexibility in choosing maternity dens (onshorevs sea ice) as well as variability in feeding areas (nearshore vs offshore)51 give polarbears the resilience they need to survive as a species

7 Southern Beaufort numbers have reboundedAccording to a preliminary US Fish amp Wildlife Service survey Southern Beaufort bearnumberswerehigher in the fall of 2012 than theyhadbeen in theprevious tenyears52

indicating a recovery from the dramatic decline (25ndash50) that occurred between2004 and 2006 because of the effects of thick spring sea ice53 For unknown rea-sons the newly-developed models used to estimate Southern Beaufort populationsize used only data up until 2010 even though mark-recapture data up until 2012were available54 This is known because the data was used for another study seeSection 8 The failure of thick spring ice conditions to recur in recent years and theearly formation and expansion of spring polynyas in the eastern Beaufort have likelybeenbeneficial for polar bears and seals55 resulting in the rare sighting of at least oneset of healthy triplet cubs in 201656

8 Barents Sea numbers have increasedThe Svalbard portion of the Barents Sea subpopulation was surveyed in 2015 andwas initially reported to have increased by 42 over the count performed in 200457

The just-publishedpaper confirms that a 42 increase in abundance indeedoccurred(685 bears in 2004 versus 973 bears in 2015)58 However due to the large uncertainty(broad error ranges) in the estimates involved even a 42 increase was not statis-tically significant This point was strongly emphasized by the PBSG59 in their recentstatus update for the Barents Sea

Becauseof theoverlapping confidence intervals it cannot be concluded that theBS subpopulation has grown60

The authors of the Svalbard survey however had this to say

6

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

3 Abrupt summer sea ice decline has not affectedpolar bear numbers as predicted

Arctic sea ice has declined since satellite records began in 1979 but polar bears haveso far adjusted well to this change especially to the sudden decline to reduced sum-mer sea ice levels that have been the norm since 2007 The degree of abrupt dropin summer sea ice that occurred in 2007 was not predicted by experts to occur untilmid-century However the predicted decimation of polar bears worldwide expectedunder mid-century conditions (Figure 3)31 ndash which entailed a loss of 23 of the globaltotal (to only about 6660ndash8325 bears) as well as the total extermination of 10 entiresubpopulations ndash not only failed to occur it did not come even close to happening32

If the experts had been right back in 2007 there would be no polar bears at all inthe Southern Beaufort or Western Hudson Bay this year33 There is also evidence thatless summer ice in the Central Canadian Arctic has already been beneficial for polarbears34 an advantage not expected until later this century This is due in part to thefact that less summer ice is good for ringed seals - on which polar bears prey ndash whichfeed primarily during the ice-free season (see Section 5) and which do best with first-year ice cover during the spring birthing and mating seasons

(a) (b)

Figure 3 Predicted sea ice changes versus outturn(a) Predictions based on 2004 data for 2020 (light grey) 2050 (mid grey) and 2080(dark grey) These were used in 2007 to predict a 66 decline in global polar bearnumbers (b) Situation as at 10 September 2012 an example of the sea ice extent

experienced in since 200735 See Crockford 2017 for details2

4

4 Chukchi Sea population is thrivingThe results of a new study published in 2013 were a direct contradiction of the re-peatedmessage that recent large sea-ice declines in late summer hadput these bearsin peril36 The paper showed that Chukchi polar bears are doingbetter than theywerein the 1980s37 and better than any others except the bears of Foxe Basin (northernHudson Bay) who are doing exceptionally well38

There is still no official population estimate for the Chukchi Sea the population isofficially listed as zero but was previously estimated at about 2000 individuals How-ever it appears that record-breaking sea-ice levels in September 2007 the lowestsince 1979 had no discernible effect on Chukchi Sea polar bears39 as confirmed byresearch up to 2016240 As a result the status of this population was upgraded fromlsquodecliningrsquo to lsquodata deficientrsquo by the PBSG in 201341 Despite the gloomy predictions alonger-than-average ice-freeperiodhas actually beengood forChukchi polar bears42

5 More preymeans healthier polar bearsThe reason Chukchi Sea polar bears did so well with an extended open-water sea-son was because ringed seals their primary prey do most of their feeding in ice-freesummer waters More fat seals mean more fat seal pups the following spring for po-lar bears A recent study found that in recent years with extensive September sea-iceminimums the summer feedingperiod for sealswas extendedand theybecameextrafat43 This meant that some seals provided a more energy-rich food source for polarbears over the following fall and winter an immediate benefit to the bears In addi-tion well-fed female ringed seals produced fat healthy pups the next spring whichmeant more food for polar bears when they needed it the most

Between 2008 and 2011 both ringed seals and polar bears did better than eitherhad done in the 1980s when summer sea ice coverage was more extensive Oddlyin March 2013 less than six months after ringed seals were placed on the Americanlist of species lsquothreatenedrsquo with extinction44 ringed seal biologists were reporting totheir peers that the results of their Chukchi Sea research contradicted their dire pre-dictions45 Surprisingly to them less summer sea ice was better for ringed seals notworse In July 2014 a judge decreed that the 2012 decision to list bearded seals inAlaska as lsquothreatenedrsquo was deficient and that there were no near-term threats Thejudge called it lsquoan abuse of discretionrsquo46

The USA stands out as the only nation that insists that Arctic seals have been (orwill be shortly) harmed by recent declines in summer sea ice47 which made it all themore surprising that in September 2017 the US Fish andWildlife Service announcedit would not pursue a plan to list Pacific walrus as lsquothreatenedrsquo with extinction underthe Endangered Species Act48 Their experts concluded there was no evidence of on-going harm or an imminent threat to walrus survival

5

6 Polar bears are adaptablePolar bears have been shown to move from areas with unsuitable ice to areas withbetter ice conditions even over the short term This is strong evidence of their abilityto adapt to changing sea ice Recently it was noted that a number of bears from theBarents Seawhere sea-ice coverage is strongly influencedbyvariations in theAtlanticMultidecadal Oscillation49 moved to the islands of the Franz Josef Land archipelagoin the Kara Sea where there has beenmore predictable ice cover50 This is just one ex-ample of polar bear flexibility A past example was the movement of Southern Beau-fort bears into the Chukchi Sea during the catastrophic 1974ndash1976 episode of thickspring ice in the Eastern Beaufort Flexibility in choosing maternity dens (onshorevs sea ice) as well as variability in feeding areas (nearshore vs offshore)51 give polarbears the resilience they need to survive as a species

7 Southern Beaufort numbers have reboundedAccording to a preliminary US Fish amp Wildlife Service survey Southern Beaufort bearnumberswerehigher in the fall of 2012 than theyhadbeen in theprevious tenyears52

indicating a recovery from the dramatic decline (25ndash50) that occurred between2004 and 2006 because of the effects of thick spring sea ice53 For unknown rea-sons the newly-developed models used to estimate Southern Beaufort populationsize used only data up until 2010 even though mark-recapture data up until 2012were available54 This is known because the data was used for another study seeSection 8 The failure of thick spring ice conditions to recur in recent years and theearly formation and expansion of spring polynyas in the eastern Beaufort have likelybeenbeneficial for polar bears and seals55 resulting in the rare sighting of at least oneset of healthy triplet cubs in 201656

8 Barents Sea numbers have increasedThe Svalbard portion of the Barents Sea subpopulation was surveyed in 2015 andwas initially reported to have increased by 42 over the count performed in 200457

The just-publishedpaper confirms that a 42 increase in abundance indeedoccurred(685 bears in 2004 versus 973 bears in 2015)58 However due to the large uncertainty(broad error ranges) in the estimates involved even a 42 increase was not statis-tically significant This point was strongly emphasized by the PBSG59 in their recentstatus update for the Barents Sea

Becauseof theoverlapping confidence intervals it cannot be concluded that theBS subpopulation has grown60

The authors of the Svalbard survey however had this to say

6

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

4 Chukchi Sea population is thrivingThe results of a new study published in 2013 were a direct contradiction of the re-peatedmessage that recent large sea-ice declines in late summer hadput these bearsin peril36 The paper showed that Chukchi polar bears are doingbetter than theywerein the 1980s37 and better than any others except the bears of Foxe Basin (northernHudson Bay) who are doing exceptionally well38

There is still no official population estimate for the Chukchi Sea the population isofficially listed as zero but was previously estimated at about 2000 individuals How-ever it appears that record-breaking sea-ice levels in September 2007 the lowestsince 1979 had no discernible effect on Chukchi Sea polar bears39 as confirmed byresearch up to 2016240 As a result the status of this population was upgraded fromlsquodecliningrsquo to lsquodata deficientrsquo by the PBSG in 201341 Despite the gloomy predictions alonger-than-average ice-freeperiodhas actually beengood forChukchi polar bears42

5 More preymeans healthier polar bearsThe reason Chukchi Sea polar bears did so well with an extended open-water sea-son was because ringed seals their primary prey do most of their feeding in ice-freesummer waters More fat seals mean more fat seal pups the following spring for po-lar bears A recent study found that in recent years with extensive September sea-iceminimums the summer feedingperiod for sealswas extendedand theybecameextrafat43 This meant that some seals provided a more energy-rich food source for polarbears over the following fall and winter an immediate benefit to the bears In addi-tion well-fed female ringed seals produced fat healthy pups the next spring whichmeant more food for polar bears when they needed it the most

Between 2008 and 2011 both ringed seals and polar bears did better than eitherhad done in the 1980s when summer sea ice coverage was more extensive Oddlyin March 2013 less than six months after ringed seals were placed on the Americanlist of species lsquothreatenedrsquo with extinction44 ringed seal biologists were reporting totheir peers that the results of their Chukchi Sea research contradicted their dire pre-dictions45 Surprisingly to them less summer sea ice was better for ringed seals notworse In July 2014 a judge decreed that the 2012 decision to list bearded seals inAlaska as lsquothreatenedrsquo was deficient and that there were no near-term threats Thejudge called it lsquoan abuse of discretionrsquo46

The USA stands out as the only nation that insists that Arctic seals have been (orwill be shortly) harmed by recent declines in summer sea ice47 which made it all themore surprising that in September 2017 the US Fish andWildlife Service announcedit would not pursue a plan to list Pacific walrus as lsquothreatenedrsquo with extinction underthe Endangered Species Act48 Their experts concluded there was no evidence of on-going harm or an imminent threat to walrus survival

5

6 Polar bears are adaptablePolar bears have been shown to move from areas with unsuitable ice to areas withbetter ice conditions even over the short term This is strong evidence of their abilityto adapt to changing sea ice Recently it was noted that a number of bears from theBarents Seawhere sea-ice coverage is strongly influencedbyvariations in theAtlanticMultidecadal Oscillation49 moved to the islands of the Franz Josef Land archipelagoin the Kara Sea where there has beenmore predictable ice cover50 This is just one ex-ample of polar bear flexibility A past example was the movement of Southern Beau-fort bears into the Chukchi Sea during the catastrophic 1974ndash1976 episode of thickspring ice in the Eastern Beaufort Flexibility in choosing maternity dens (onshorevs sea ice) as well as variability in feeding areas (nearshore vs offshore)51 give polarbears the resilience they need to survive as a species

7 Southern Beaufort numbers have reboundedAccording to a preliminary US Fish amp Wildlife Service survey Southern Beaufort bearnumberswerehigher in the fall of 2012 than theyhadbeen in theprevious tenyears52

indicating a recovery from the dramatic decline (25ndash50) that occurred between2004 and 2006 because of the effects of thick spring sea ice53 For unknown rea-sons the newly-developed models used to estimate Southern Beaufort populationsize used only data up until 2010 even though mark-recapture data up until 2012were available54 This is known because the data was used for another study seeSection 8 The failure of thick spring ice conditions to recur in recent years and theearly formation and expansion of spring polynyas in the eastern Beaufort have likelybeenbeneficial for polar bears and seals55 resulting in the rare sighting of at least oneset of healthy triplet cubs in 201656

8 Barents Sea numbers have increasedThe Svalbard portion of the Barents Sea subpopulation was surveyed in 2015 andwas initially reported to have increased by 42 over the count performed in 200457

The just-publishedpaper confirms that a 42 increase in abundance indeedoccurred(685 bears in 2004 versus 973 bears in 2015)58 However due to the large uncertainty(broad error ranges) in the estimates involved even a 42 increase was not statis-tically significant This point was strongly emphasized by the PBSG59 in their recentstatus update for the Barents Sea

Becauseof theoverlapping confidence intervals it cannot be concluded that theBS subpopulation has grown60

The authors of the Svalbard survey however had this to say

6

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

6 Polar bears are adaptablePolar bears have been shown to move from areas with unsuitable ice to areas withbetter ice conditions even over the short term This is strong evidence of their abilityto adapt to changing sea ice Recently it was noted that a number of bears from theBarents Seawhere sea-ice coverage is strongly influencedbyvariations in theAtlanticMultidecadal Oscillation49 moved to the islands of the Franz Josef Land archipelagoin the Kara Sea where there has beenmore predictable ice cover50 This is just one ex-ample of polar bear flexibility A past example was the movement of Southern Beau-fort bears into the Chukchi Sea during the catastrophic 1974ndash1976 episode of thickspring ice in the Eastern Beaufort Flexibility in choosing maternity dens (onshorevs sea ice) as well as variability in feeding areas (nearshore vs offshore)51 give polarbears the resilience they need to survive as a species

7 Southern Beaufort numbers have reboundedAccording to a preliminary US Fish amp Wildlife Service survey Southern Beaufort bearnumberswerehigher in the fall of 2012 than theyhadbeen in theprevious tenyears52

indicating a recovery from the dramatic decline (25ndash50) that occurred between2004 and 2006 because of the effects of thick spring sea ice53 For unknown rea-sons the newly-developed models used to estimate Southern Beaufort populationsize used only data up until 2010 even though mark-recapture data up until 2012were available54 This is known because the data was used for another study seeSection 8 The failure of thick spring ice conditions to recur in recent years and theearly formation and expansion of spring polynyas in the eastern Beaufort have likelybeenbeneficial for polar bears and seals55 resulting in the rare sighting of at least oneset of healthy triplet cubs in 201656

8 Barents Sea numbers have increasedThe Svalbard portion of the Barents Sea subpopulation was surveyed in 2015 andwas initially reported to have increased by 42 over the count performed in 200457

The just-publishedpaper confirms that a 42 increase in abundance indeedoccurred(685 bears in 2004 versus 973 bears in 2015)58 However due to the large uncertainty(broad error ranges) in the estimates involved even a 42 increase was not statis-tically significant This point was strongly emphasized by the PBSG59 in their recentstatus update for the Barents Sea

Becauseof theoverlapping confidence intervals it cannot be concluded that theBS subpopulation has grown60

The authors of the Svalbard survey however had this to say

6

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

There is no evidence that the fast reduction of sea-ice habitat in the area hasyet led to a reduction in population size The carrying capacity is likely reducedsignificantly but recovery fromearlier depletionup to 1973may still be ongoing

9 Low sea ice in 2012 had no harmful effect onSouthern Beaufort bear numbers

Thedramatically lowSeptember sea ice of 2012 apparently hadnoeffect on SouthernBeaufort Sea polar bear numbers or at least we have heard nothing to indicate anyadverse effects61 Even though 2012 had the longest open-water period in the South-ern Beaufort since at least 1979 (see Figure 4) researchers doingmark-recaptureworkin the area did not report large numbers of starving bears during the summer of 2012or in the spring of 201362 Instead an aerial survey conducted in the fall of 2012 re-ported that numbers were higher than they had been in a decade (see Section 7)That is because the extent of sea ice in early summer and late fall means little to polarbears in part because most bears eat very little then even if they are on the ice63

10 Other species impacted by high polar bearnumbers

There are somany polar bears in the Foxe Basin64 and the southern Davis Strait65 (Fig-ure 5) that they may be decimating some nesting sea bird colonies66 If so then thiswould represent a downside of there being too many bears And in Western Hud-son Bay polar bears have been reported eating record numbers of caribou and snowgeese because populations of these prey animals are higher than they have been indecades67 Such welcome food sources for eastern Canadian bears provide a little re-lief from their summer fast as whale carcasses do for western bears68 (such as thoseat Kaktovik69 in the Beaufort Sea or onWrangel Island in the Chukchi Sea70) Howeverall evidence suggests that such terrestrial foods are not necessary for bears that havefed well during the previous spring71 whether on land or out on the ice most polarbears eat very little over the late summerearly fall months72

11 Western Hudson Bay population numbers arestable

Western Hudson Bay polar bear numbers have stabilized73 Numbers have not con-tinued to decline precipitously as predicted after amodest decline between 1987 and200474 Differentmethods of calculating an estimate includingwhich portions of theregion were surveyed have generated numbers that look like a large population de-

7

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

Figure 4 Sea ice extent at the 2012 late summer minimum As at 16 September 2012Source NSIDC

cline has taken place when no such change has actually happened75767778 In shortwhile theremay have been a slight decline in numbers since 2004 there has not beena statistically-significant decline79 and the just-released results of a 2016 survey con-firm this conclusion75 There were 949 bears in 2011 (range 618ndash1280) and 842 bearsin 2016 (range 562ndash1121) a statistically insignificant decline of about 11 You maystill find people saying that Western Hudson Bay polar bear numbers have droppedfrom about 1200 (in 1987) to about 800 now (a 33 decline)80 However it is notscientifically appropriate to compare these figures because they were based on dif-ferent types of surveys conducted over different portions of the region81 The officialWesternHudsonBay estimate acceptedby the PBSG in 2014 andby the IUCN in 2015is 1030 bears (range 754ndash1406 about 10 higher than but not statistically different

8

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

SB

BB

DSFB

WH

Figure 5 Some polar bear assessment areasSB Southern Beaufort Sea BB Baffin Bay FB Foxe Basin WH Western Hudson Bay DS

Davis Strait

from the 935 bears estimated in 2004 because the ranges overlap)82 EnvironmentCanada (2014) considered thepopulation lsquolikely stablersquo (see Section 2) an assessmentupheld by the latest survey

9

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

12 Hudson Bay sea ice is not changingmuchFor the last three years break-up dates forWestern Hudson Bay have been somewhatlater than the recent average in 201683 and 201784 bears came off the ice frommid-to late-July while in 2015 some bears did not come ashore until early August85 Onthe other hand freeze-up in 201686 ndash an official El Nintildeo year ndash was quite late (earlyDecember) as it was during the El Nintildeo year of 1998 However freeze-up was alsojust as late in 1983 1999 2003 and 2010 Surprisingly 2017 looks headed for anearly freeze-up87 In other words freeze-up dates are quite variable year to year andso are breakup dates88

All of this suggests that in Western Hudson Bay some years have been good forpolar bears and others have been not so good but there has not been a relentlesscontinuing decline in sea-ice breakup dates over the last thirty years that has forcedbears onshore for ever-lengthening periods of time89 This has allowed polar bearsto adapt via natural selection90 A paper published in 2017 showed that between2004 and 2015 polar bears spent about three weeks longer on shore than they did inthe 1980s The step-change in the length of the ice-free period occurred in the late1980s91 and it appears that polar bears have adapted to it92

13 Problembears in Churchill are not lean or starvingThe Canadian Broadcasting Corporation recently produced a relatively balanced doc-umentary about someof the controversies involved in polar bear conservation calledThe Politics of Polar Bears93 It included an interview with the head conservation offi-cer in Churchill who noted that virtually none of the lsquoproblem bearsrsquo (see Section 14)captured over the last five years were starving or lean Churchill Polar Bear Alert re-ports for 201694 and 201795 stated that bears coming off the ice at mid-summer werein lsquogreat shapersquo This suggests that many of the polar bear problems experienced byWestern Hudson Bay communities in recent years are due to higher numbers of bears(or a redistributionofbears especially of sub-adultmales) ndash aspredictedbypolar bearbiologist Ian Stirling in the 1970s96 ndash combined with other factors (such as increasednumbers of residents and tourists and their associated attractants) Sea-ice changesare unlikely to be a cause

14 Churchill Manitoba had themost problem bearsin 1983 and 2016

The first of the twoworst years for problembears in Churchill that could be correlatedwith lack of sea ice happened back in 1983 when the last human fatality from a polarbear attack occurred Ironically 1983 was a year when breakup of sea ice was laterthan usual so the bears had more time on the ice to feed Unfortunately freeze-up

10

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

was also much later than usual leaving many bears in a very lean state and unableto resume hunting until early December Similar conditions prevailed for the secondworst year (2016) which also had late breakup and late freeze-up Hundreds of prob-lem bears had to be dealt with in 2016 although the high number was partly an ef-fect of ice conditions and partly the result of a zero-tolerance policy for bears close totown97 implemented after an attack on a resident in 201398 Breakup and freeze-updates for Western Hudson Bay are highly variable (see Section 12) and do not corre-late well with high or low Arctic sea-ice levels in September (Figure 6) In some yearsthenumber of problembears inChurchill does not correlatewellwithbreakupandorfreeze-up dates because critical ice and snow conditions during the spring are nevertaken into account99 As of late October there have been fewer problem bears inChurchill in 2017 than in 2016100

20

10

0

-10

-20

-30

-40

1979 1984 1989 1994 1999 2004 2009 2014

MarchSeptember

Figure 6 Arctic sea-ice levels 1978ndash2014Source NOAArsquos lsquoArctic Report Card 2014rsquo Note the lack of error bars indicating theestimated accuracy of each value which should be present on a scientific graph

15 Marginal sea ice declines during the feedingperiod

Across the Arctic there has been only a marginal decline in total sea ice extent (Fig-ure 6) between March and June the critical spring feeding period when polar bearsrequire the ice as a hunting platform for gorging on young fat seals Polar bears con-

11

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

sume two-thirds or more of their yearly food intake during this time they generallyeat little during the summer101 whether on land or on the ice Feeding picks up againin the fall but declines over the winter explaining why polar bears everywhere areleanest at the end of winter102 just before Arctic seals pups are born and fattest inearly summer103

In 2017 sea ice levels during the springwerehigher thanusual in the Labrador Sea(home to Davis Strait polar bears)104 and as a consequence communities in coastalLabrador and Newfoundland saw record-breaking numbers of bear sightings105 in-cluding a scary encounter that resulted in a bear being shot106

16 No evidence that subsistence hunting is affectingbear populations

There is no plausible evidence that regulated subsistence hunting is causing polarbear numbers to decline despite suspicions harboured by PBSG biologists The oneregion where overhunting was suspected but not proven107 to have caused a differ-ence to population numbers is Baffin Bay108 However results of a recent populationsurvey refute that assumption the population did not decline due to overhuntingbut instead increased 36 over the previous estimate (see Section 2)28

17 Stressful researchmethods have been curtailedMany polar bear biologists have stopped putting satellite radio collars on polar bearsand have turned to other methods to gather population size data a step that meansless handling stress for the bears In some regions such as the Barents and ChukchiSeas large-scale markndashrecapture studies would be logistically impractical althoughsome small projects are conducted in the Barents Sea109 In other areas repeatedcapture each involving a helicopter chase and use of tranquilizer guns is seen byArctic residents as stressful for the bears especially females with young cubs Alsothe drug residues are potentially bad news for aboriginal hunters and their familieswho eat themeat110 Oddly polar bear biologists chose to dispel the serious concernsover invasive research by presenting the outputs of computer models111

At the moment in most regions of Canada with polar bears (Figure 7) includ-ing Nunavut the Northwest Territories and Quebec permits are no longer being ap-proved for mark-recapture work112 Invasive research does continue in other areaswithin Canada113 especially Western and Southern Hudson Bay Labrador and New-foundland andbeyond particularly in theSouthernBeaufort114 andEastGreenland115

12

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

NorthwestTerritories Nunavut

Manitoba

OntarioQuebec

Labrador andNewfoundland

Figure 7 Polar bear research regimes in CanadaRed permits no longer issued green markndashrecapture still permitted

18 No recent reports of polar bear cannibalismAs of 2017 there have been no further reports of polar bear cannibalism since atleast 2011 and no reports of den collapses due to unusually warm winter or early-spring temperatures since 1990116 even though 2012 had the lowest summer ice ex-tent since 1979 Even in regions where bears are reportedly under stress (such as theSouthern Beaufort Western Hudson Bay and the Barents Sea) we have not had anyfurther reports of cannibalism117 or den-collapse deaths either through themedia orin the published literature

13

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

19 Polar bears appear unaffected by pollutionSo-called lsquotoxicrsquo chemicals cycle from human use into the environment move up thefood chain especially through animal fat As top Arctic predators that consume lotsof fat polar bears have thepotential to retainmore of these toxins thanother animalsHowever most of the papers published so far on this topic fail to demonstrate thatany damage to polar bear health ndash or even alterations to established biochemistry ndashhave taken place118 The effects discussed are virtually all theoretical

East Greenland bears appear to be the most lsquopollutedrsquo of all polar bears tested sofar119 yet they seem to be doing well Even their penis bones are holding up120 re-ports that polar bear penis bones have been breaking due to weakening bone struc-ture causedby retained toxic environmental chemicals have sensationalized the orig-inal report121 whichonly said thebones could perhaps break The samecaveats applyto a just-published paper on toxic chemicals found in Hudson Bay polar bears122 al-though such chemicals could perhaps affect their health no empirical evidence forany harmful effects has been shown

20 Polar bears have survived past warm periodsOne of the most recent genetic studies published emphasized that polar bears as aspecies survived more than one previous warm period when there was virtually nosummer sea ice123 Sea ice has varied both over the short term (ie decades-longclimate oscillations) and the long term (glacial-to-interglacial cycles of thousands ofyears) Over the last 100000 years for example there have been periods of muchless ice than today but also periods with much much more124 Polar bear popula-tion numbers probably fluctuated up and down in conjunction with these sea icechanges125 but the polar bear as a species survived126 and so did all of the Arcticseal species they depend on for food including Pacific walrus (a species limited byfood127 not sea ice) Their survival indicates that these Arctic species in an evolution-ary sense are very well-adapted to their highly-variable habitat128 despite their lowgenetic diversity129

ConclusionThese are all good reasons to feel good about the current status of the polar bearPolar bears are not threatened130 with extinction due to declining sea ice despite thehue and cry from activist scientists131 and environmental organizations132 Indeedbecause the polar bear is doing so well133 those who would like to see polar bearslisted as lsquovulnerablersquo on the IUCN Red List depend entirely upon emotional prophe-cies of summer sea-ice declines decades from now to make their case134 They wantpublicity but they certainly donrsquot want the public to realize how poor were their pre-

14

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

vious pessimistic predictions about the response of polar bears to low summer seaice135 or to notice how nearly all polar bear photos published in recent years showfat healthy animals136 or to observe that healthy triplet cubs (a rare phenomenonthat supposedly no longer exists in Western Hudson Bay137 where they used to becommon138) have been photographed in Western Hudson Bay (2017)139 the South-ern Beaufort Sea (2016)140 and the Chukchi Sea141 Tens of thousands of polar bearsdid not die as a result of more than a decade of low summer sea ice for one simplereason polar bears donrsquot need sea ice in late summerearly fall as long as they arewell-fed in the spring

15

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

Notes1 httpswwwamazoncomsref=dp_byline_sr_book_1ie=UTF8amptext=Susan+J+Crockfordampsearch-alias=booksampfield-author=Susan+J+Crockfordampsort=relevancerank and httpssusancrockfordcom2 Crockford S 2017 Testing the hypothesis that routine sea ice coverage of 3ndash5million km2

results in a greater than 30decline in population size of polar bears (Ursusmaritimus) PeerJPreprints 2 March 2017 Doi 107287peerjpreprints2737v33 Crockford S August 2017 The death of a climate icon httpwwwthegwpforggwpftvtubepress_item=XCzwFalI8OQ4 Crockford S February 2017 Polar bear scare unmasked the saga of a toppled globalwarming icon httpwwwthegwpforggwpftvtubepress_item=z6bcCTFnGZ05 Crockford S October 2014The walrus fuss walrus haulouts are nothing new httpwwwthegwpforggwpftvtubepress_item=cwaAwsS2OOYamptubepress_page=26 Crockford S October 2014 On the beach walrus haulouts are nothing new httpwwwthegwpforgsusan-crockford-on-the-beach-27 Crockford S July 2015 The Arctic fallacy sea ice stability and the polar bear httpwwwthegwpforgsusan-crockford-the-arctic-fallacy-28 Crockford S April 2015 Twenty reasons not to worry about polar bears (2015) httpwwwthegwpforg20-reasons-to-be-cheerful-on-international-polar-bear-day-2015-29 Polar Bear Week (Amstrup S)

an event created by my colleagues at Polar Bears International to draw atten-tion to sea ice loss in the Arctic and the urgent need to halt the global rise intemperatures causing the ice to melt This year Polar Bear Week coincides withthe COP23 climate change conference in Bonn Germany The overlap is fittingPolar bears are the premier symbol of global warming with their very survivalthreatened by melting habitat

See httpswwwhuffingtonpostcomentryand-now-germany-must-lead_us_59f740dfe4b06ae9067aba6110 Polar Bear Week 2017 httpspolarbearsinternationalorgget-involvedpolar-bear-week11 httpswwwthegwpforgcontentuploads20150620reasonspdf12 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml13 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056814 httpswwwwashingtonpostcomnewsenergy-environmentwp20170109without-action-on-climate-change-say-goodbye-to-polar-bearsutm_term=7bbf4040d6f915 httpnewsroomunfcccintcop-23-bonn16 httppolarbearsciencecom20150101iucn-polar-bear-specialist-groupout-lived-its-usefulness-20-years-ago17 httpspolarbearsciencecom20170412global-polar-bear-population-size-is-about-28500-when-updates-are-included

16

18 httppolarbearsciencecom20140218graphing-polar-bear-population-estimates-over-time19 httppbsgnpolarnoenstatuspb-global-estimatehtml20 httpspolarbearsciencecom20170501iucn-specialist-group-now-rejects-polar-bear-numbers-it-used-for-2015-iucn-red-list-review21 Wiig Oslash Amstrup S Atwood T Laidre K Lunn N Obbard M et al 2015 Ursusmaritimus The IUCN Red List of Threatened Species 2015 eT22823A14871490 httpwwwiucnredlistorgdetails22823022 httppolarbearsciencecom20140705are-polar-bears-really-endangered23 httppolarbearsciencecom20150128claim-of-range-contraction-of-polar-bears-due-to-declines-in-summer-sea-ice-doesnt-hold-up24 httpwwwbbccomearthstory20141107-will-polar-bears-become-extinct25 httppolarbearsciencecom20141219challenging-noaas-arctic-report-card-2014-on-polar-bears httppbsgnpolarnoenstatuspb-global-estimatehtml26 httpswwwecgccanaturedefaultasplang=Enampn=F77294A3-1_fig0427 httppolarbearsciencecom20141028status-of-canadian-polar-bear-populations-has-been-changed-more-good-news28 httpspolarbearsciencecom20170215baffin-bay-and-kane-basin-polar-bears-not-declining-concludes-new-report29 httppolarbearsciencecom20141230kara-sea-first-ever-polar-bear-count-suggests-about-3200-bears-live-there30 httpswwwecgccanaturedefaultasplang=Enampn=F77294A3-1_fig0431 httpspolarbearsciencecom20170119new-paper-asks-has-recent-sea-ice-loss-caused-polar-bear-populations-to-crash32 httpspolarbearsciencecom20170714abrupt-summer-sea-ice-decline-has-not-affected-polar-bear-numbers-as-predicted33 httppolarbearsciencecom20161221as-polar-bear-populations-fail-to-decline-with-sea-ice-message-of-doom-intensifies34 httpspolarbearsciencecom20170426experts-vision-of-an-ice-free-summer-is-already-wrong-benefitting-polar-bears35 httpspolarbearsciencecom20170119new-paper-asks-has-recent-sea-ice-loss-caused-polar-bear-populations-to-crash36 httppolarbearsciencecom20130707chukchi-polar-bear-status-contradicts-the-message-new-details37 httppolarbearsciencecom20130908how-and-why-great-news-about-chukchi-polar-bears-has-been-suppressed38 httppolarbearsciencecom20140212foxe-basin-polar-bear-status-another-stable-population39 httppolarbearsciencecom20130915record-sea-ice-loss-in-2007-had-no-effect-on-polar-bears-chukchi-study-confirms40 Rode et al 2017 Spring fasting behavior in a marine apex predator provides an index ofecosystem productivity Global Change Biology httponlinelibrarywileycomdoi101111gcb13933full

17

41 httpspolarbearsciencefileswordpresscom201402summary-of-polar-bear-population-status-per-2013-pbsg_npolar_no_en_status_status-table_htm_feb-14-2014pdf42 httppolarbearsciencecom20150112if-summer-ice-was-critical-for-s-beaufort-polar-bears-2012-would-have-decimated-them43 httppolarbearsciencecom20130711chukchibering-sea-ringed-seals-doing-better-despite-declines-in-ice-and-snow-new-study44 httppolarbearsciencecom20121230bearded-and-ringed-seals-join-the-polar-bear-as-threatened-by-a-computer-modeled-future45 httppolarbearsciencecom20130711chukchibering-sea-ringed-seals-doing-better-despite-declines-in-ice-and-snow-new-study46 httppolarbearsciencecom20140727bearded-seals-in-alaska-face-no-serious-threat-of-reduction-let-alone-extinction-judge-rules47 httppolarbearsciencecom20141231threatened-arctic-species-comparison-shows-usa-most-assertive-about-global-warming48 httpspolarbearsciencecom20171004breaking-pacific-walrus-is-not-threatened-with-extinction-says-us-fish-wildlife49 httppolarbearsciencecom20140310barents-sea-polar-bear-condition-varies-with-amo-and-spring-sea-ice-conditions50 httppolarbearsciencecom20140414polar-bears-move-around-as-sea-ice-habitat-changes-this-is-what-resilience-looks-like51 httppolarbearsciencecom20140820summer-sea-ice-melt-and-polar-bear-maternity-dens52 httpspolarbearsciencefileswordpresscom201403usfws-2013-2014-polar-bear-newsletter_smpdf see p 17 lower right See also httppolarbearsciencecom20141119polar-bear-researchers-knew-s-beaufort-population-continued-to-increase-up-to-201253 httpspolarbearsciencecom20170611usgs-treadmill-paper-repeats-bogus-claim-that-ice-loss-harmed-polar-bears54 httppolarbearsciencecom20141217recent-s-beaufort-polar-bear-count-was-a-cherry-picked-result-new-evidence55 httpspolarbearsciencecom20170522southern-beaufort-sea-ice-melt-in-may-good-news-for-polar-bears-or-catastrophe56 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml57 httpspolarbearsciencecom20151223survey-results-svalbard-polar-bear-numbers-increased-42-over-last-11-years58 Aars J MarquesTA Lone K et al 2017 The number and distribution of polar bears inthe western Barents Sea Polar Research 361 1374125 See Table 359 httpspolarbearsciencecom20170501iucn-pbsg-insists-the-2015-barents-sea-polar-bear-count-was-not-an-increase60 httppbsgnpolarnoenstatuspopulationsbarents-seahtml61 httppolarbearsciencecom20150112if-summer-ice-was-critical-for-s-beaufort-polar-bears-2012-would-have-decimated-them62 httpwwwusgsgovnewsroomarticleaspID=4075VJCA2Xt5Yvy

18

63 httppolarbearsciencecom20150209polar-bears-out-on-the-sea-ice-eat-few-seals-in-summer-and-early-fall64 httppolarbearsciencecom20140212foxe-basin-polar-bear-status-another-stable-population65 httppolarbearsciencecom20130610signs-that-davis-strait-polar-bears-are-at-carrying-capacity66 httppolarbearsciencecom20140209thriving-foxe-basin-and-davis-strait-polar-bears-threaten-nesting-sea-birds67 httppolarbearsciencecom20140126churchill-polar-bears-eat-more-caribou-and-geese-now-than-in-1968-because-there-are-more-caribou-and-geese-new-research-reveals68 httppolarbearsciencecom20131213kaktovik-polar-bear-photos-again-no-starving-bears69 httppolarbearsciencecom20130930polar-bears-at-kaktovik-alaska-not-stranded-due-to-retreating-ice70 httpswwwthesuncouknews4577222incredible-moment-more-than-230-polar-bears-descend-on-a-russian-beach-to-feast-on-a-giant-whale-carcass71 httpspolarbearsciencecom20160619terrestrial-food-fight-amongst-polar-bear-researchers-reflects-political-differences72 httppolarbearsciencecom20150209polar-bears-out-on-the-sea-ice-eat-few-seals-in-summer-and-early-fall73 httppolarbearsciencecom20141205western-hudson-bay-polar-bear-population-is-stable-press-release74 httpspolarbearsciencecom20170919breaking-2016-w-hudson-bay-polar-bear-survey-shows-the-population-is-still-stable75 Dyck M Campbell M Lee D Boulanger J and Hedman D 2017 2016 Aerial surveyof the Western Hudson Bay polar bear subpopulation Final report Nunavut Department ofEnvironment Wildlife Research Section Iglolik NU httpwwwgovnucaenvironnementinformationwildlife-research-reportspolarbear76 Lunn NJ Servanty S Regehr EV et al 2016 Demography of an apex predator atthe edge of its range ndash impacts of changing sea ice on polar bears in Hudson Bay EcologicalApplications in press DOI 10189015-125677 Regehr EV Lunn NJ Amstrup SC and Stirling I 2007 Effects of earlier sea ice breakupon survival and population size of polar bears in Western Hudson Bay Journal of WildlifeManagement 712673ndash268378 Stapleton S Atkinson S Hedman D and Garshelis D 2014 Revisiting WesternHudson Bay using aerial surveys to update polar bear abundance in a sentinel popula-tion Biological Conservation 17038ndash47 httpwwwsciencedirectcomsciencearticlepiiS000632071300461879 httpwwwcbccanewsmultimediapolar-bears-in-churchill-face-bleak-future-researchers-warn-1438056880 httpwwwtheguardiancomenvironment2013nov27polar-bears-climate-change-canada-hudson-bay httpwwwupworthycoma-scientist-who-has-studied-polar-bears-

19

for-34-years-is-starting-to-get-really-worried httpswwwtheatlanticcomsciencearchive201612trouble-in-polar-bear-capital510839 httpwwwcbccanewsthenationalpolar-bears-in-steady-decline-in-northern-manitoba-researchers-find-1438548081 httpspolarbearsciencecom20170529polar-bear-counts-for-w-hudson-bay-core-area-numbers-are-not-comparable82 Because the 2011 and 2016Western Hudson Bay aerial surveys used somewhat differentmethods the only population size numbers that can be compared are these 2011 (949 range618ndash1280) and 2016 (842 range 562ndash1121) The slight decline apparent over 5 years (11)was not statistically significant (Dyck et al 2017 pg 3 37) When differences inmethodologyand assumptions are taken into account there is no evidence to suggest the estimate for2016 is different from the 2011 estimate of 1030 bears (Stapleton et al 2014) which is notstatistically different from the estimate of 935 calculated in 2004 (Regehr et al 2007) Seeendnote 75-78 for full citations83 httpspolarbearsciencecom20160804polar-bears-off-the-ice-in-w-hudson-bay-are-well-fed-and-in-great-shape-this-year84 httpspolarbearsciencecom20170724churchill-polar-bear-report-17-23-july-20-those-ashore-appear-to-be-in-great-shape85 httppolarbearsciencecom20150729hudson-bay-davis-strait-and-foxe-basin-sea-ice-highest-since-199286 httppolarbearsciencecom20161205an-el-nino-year-late-start-to-freeze-up-on-hudson-bay-bears-gearing-up-to-hunt87 httpspolarbearsciencecom20171102early-freeze-up-in-progress-on-hudson-bay-what-a-difference-a-year-makes88 httpspolarbearsciencecom20161115no-correlation-between-freeze-up-dates-for-hudson-bay-total-arctic-ice-cover89 httpspolarbearsciencecom20131122hudson-bay-freeze-up-has-not-been-a-day-later-each-year-since-198190 httppolarbearsciencecom20140930natural-selection-helps-polar-bears-adapt-to-sea-ice-variability-which-means-some-bears-die91 httpspolarbearsciencecom20170209new-paper-updates-lack-of-trend-in-w-hudson-bay-breakupfreeze-up-dates-to-2015 httppolarbearsciencecom20150617when-was-the-earliest-ice-breakup-year-for-western-hudson-bay-polar-bears92 httpspolarbearsciencecom20170209new-paper-updates-lack-of-trend-in-w-hudson-bay-breakupfreeze-up-dates-to-201593 The long version of the program can be viewed online at httpwwwcbccaplayerShowsShowsAbsolutely+CanadianAbsolutely+ManitobaID2505861208 and a shorter (30minute) version at httpwwwcbccanewstechnologypolarbears-threatened-species-or-political-pawn-12753645 See also httpwwwcbccanewstechnologypolar-bears-threatened-species-or-political-pawn-1275364594 httpspolarbearsciencecom20160804polar-bears-off-the-ice-in-w-hudson-bay-are-well-fed-and-in-great-shape-this-year95 httpspolarbearsciencecom20170724churchill-polar-bear-report-17-23-july-20-those-ashore-appear-to-be-in-great-shape

20

96 httppolarbearsciencecom20131117human-polar-bear-conflicts-stirling-1974-vs-amstrup-201397 httpspolarbearsciencecom20160229more-churchill-polar-bear-captures-due-to-increased-vigilance-not-global-warming98 httppolarbearsciencecom20131104churchill-polar-bear-attack-shamelessly-used-to-advance-global-warming-agenda99 httppolarbearsciencecom20150514snow-depth-over-spring-sea-ice-affects-polar-bear-feeding-success-and-ringed-seal-survival100 httpspolarbearsciencecom20171102early-freeze-up-in-progress-on-hudson-bay-what-a-difference-a-year-makes101 httppolarbearsciencecom20150209polar-bears-out-on-the-sea-ice-eat-few-seals-in-summer-and-early-fall102 httpspolarbearsciencecom20170328recent-incident-in-foxe-basin-shows-the-danger-of-hungry-polar-bears-in-winter103 httpspolarbearsciencecom20170823fat-polar-bears-and-lots-of-them-drive-public-confidence-in-future-of-the-species104 httpspolarbearsciencecom20170422sea-ice-off-newfoundland-thickest-ever-yet-another-polar-bear-comes-ashore105 httpspolarbearsciencecom20170403east-coast-crawling-with-polar-bears-since-early-march-thanks-to-the-pack-ice106 httpspolarbearsciencecom20170410newfoundland-conservation-officers-right-to-kill-polar-bear-in-hunting-mode107 httppolarbearsciencecom20140227foxe-basin-aerial-survey-a-watershedmoment-for-polar-bear-research-part-2108 httppolarbearsciencecom20131111baffin-bay-polar-bear-population-survey-done-results-due-end-2014109 httppolarbearsciencecom20140602barents-sea-polar-bear-cubs-new-data-for-2014-made-to-sound-ominous110 httppolarbearsciencecom20140226tranquilizing-polar-bears-and-meat-tainted-with-drugs111 httppolarbearsciencecom20141218polar-bear-biologists-miss-the-mark-in-new-study-on-invasive-mark-recapture-effects112 Discussed at httppolarbearsciencecom20140224foxe-basin-aerial-survey-a-watershed-moment-for-polar-bear-research-part-1 and httppolarbearsciencecom20140227foxe-basin-aerial-survey-a-watershed-moment-for-polar-bear-research-part-2113 httppolarbearsciencecom20140302guest-post-invasive-research-is-alive-and-well-in-canada114 httppolarbearsciencecom20130829ten-out-of-ten-polar-bears-being-tracked-this-summer-in-the-beaufort-sea-are-on-the-ice115 httppolarbearsciencecom20150204east-greenland-polar-bears-said-to-be-the-most-polluted-but-appears-to-be-doing-just-fine116 httponlinelibrarywileycomdoi101111j1365-2486201202753xabstract

21

117 httppolarbearsciencecom20130410cannibalism-in-polar-bears-spin-and-misrepresentation-of-fact-galore118 httppolarbearsciencecom20150316no-evidence-of-actual-damage-to-polar-bear-brains-from-environmental-contaminants119 httppolarbearsciencecom20150204east-greenland-polar-bears-said-to-be-the-most-polluted-but-appears-to-be-doing-just-fine120 httppolarbearsciencecom20150128polar-bear-penises-not-breaking-due-to-pcbs-new-paper-full-of-coulds-and-maybes121 httpgristorglistwe-are-literally-breaking-polar-bear-penises-now122 httpnationalpostcompmnnews-pmncanada-news-pmnnew-chemical-cocktails-found-in-hudson-bay-polar-bears123 httppolarbearsciencecom20140317new-genetic-study-confirms-polar-bears-survived-several-warm-interglacials124 httppolarbearsciencecom20150608my-new-arctic-fallacy-paper-sea-ice-stability-and-the-polar-bear125 httppolarbearsciencecom20150421polar-bears-barely-survived-the-sea-ice-habitat-changes-of-the-last-ice-age-evidence-suggests126 httppolarbearsciencecom20160109paleoclimate-genetic-study-confirms-arctic-species-adapted-to-sea-ice-changes127 httppolarbearsciencecom20141023walrus-mass-haulout-hype-refuted-the-video128 httppolarbearsciencecom20140930natural-selection-helps-polar-bears-adapt-to-sea-ice-variability-which-means-some-bears-die129 httppolarbearsciencecom20160114genetic-similarity-of-polar-bears-does-not-make-them-vulnerable-to-global-warming130 httpwwwbbccomearthstory20141107-will-polar-bears-become-extinct131 httpspolarbearsciencecom20170109fake-news-on-polar-bear-survival-predictions-is-political-posturing132 httppolarbearsciencecom20140618center-for-biological-diversity-provides-a-public-disservice-on-polar-bear-status133 httpspolarbearsciencecom20170831video-death-of-a-climate-icon-the-polar-bears-demise-as-a-useful-poster-child134 httpspolarbearsciencecom20161207polar-bears-that-didnt-die-from-recent-sea-ice-loss-will-die-in-35-yrs-say-sperts135 httppolarbearsciencecom20161221as-polar-bear-populations-fail-to-decline-with-sea-ice-message-of-doom-intensifies136 httpspolarbearsciencecom20170823fat-polar-bears-and-lots-of-them-drive-public-confidence-in-future-of-the-species httpspolarbearsciencecom20171001fat-healthy-polar-bear-update-hundreds-of-not-starving-bears-attracted-to-dead-whale137 httpwwwcbccanewsthenationalpolar-bears-in-steady-decline-in-northern-manitoba-researchers-find-14385480138 httppolarbearsciencecom20120926western-hudson-bay-polar-bears-are-not-like-the-others-part-1

22

139 httpswwwchurchillwildcompolar-bear-triplets-highlight-summer-at-seal-river-heritage-lodge140 httpswwwnytimescom20161218sciencepolar-bears-global-warminghtml141 httpspolarbearsciencecom20160225ten-dire-polar-bear-predictions-that-have-failed-as-global-population-hits-22-31k

GWPF BRIEFINGS1 Andrew Turnbull The Really Inconvenient Truth or lsquoIt Ainrsquot Necessarily Sorsquo2 Philipp Mueller The Greening of the Sahel3 William Happer The Truth about Greenhouse Gases4 Gordon Hughes The Impact of Wind Power on Household Energy Bills5 Matt Ridley The Perils of Confirmation Bias6 Philipp Mueller The Abundance of Fossil Fuels7 Indur Goklany Is Global Warming the Number One Threat to Humanity8 Andrew Montford The Climate Model and the Public Purse9 Philipp Mueller UK Energy Security Myth and Reality10 Andrew Montford Precipitation Deluge and Flood11 Susan Crockford On the Beach12 Madhav Khandekar Floods and Droughts in the Indian Monsoon13 Indur Goklany Unhealthy Exaggeration14 Susan Crockford Twenty Reasons not to Worry about Polar Bears15 Various The Small Print16 Susan Crockford The Arctic Fallacy17 Indur Goklany The Many Benefits of Carbon Dioxide18 Judith Curry The Climate Debate in the USA19 Indur Goklany The Papal Academiesrsquo Broken Moral Compass20 Donoughue and Forster The Papal Encyclical a Critical Christian Response21 Andrew Montford Parched Earth Policy Drought Heatwave and Conflict22 David Campbell The Paris Agreement and the Fifth Carbon Budget23 Various The Stern Review Ten Years of Harm24 Judith Curry Climate Models for the Layman25 Fritz Vahrenholt Germanyrsquos Energiewende a Disaster in the Making26 Hughes Aris Constable Offshore Wind Strike Prices27 Michael Miersch Truly Green28 Susan Crockford 20 Good Reasons Not to Worry About Polar Bears

TheGlobalWarming Policy Foundation is an all-party and non-party thinktank and a registered educational charity which while openminded onthe contested science of global warming is deeply concerned about thecosts and other implications ofmany of the policies currently being advo-cated

Our main focus is to analyse global warming policies and their economicand other implications Our aim is to provide themost robust and reliableeconomic analysis and advice Above all we seek to inform the mediapoliticians and the public in a newsworthy way on the subject in generaland on themisinformation towhich they are all too frequently being sub-jected at the present time

The key to the success of theGWPF is the trust and credibility thatwehaveearned in the eyes of a growing number of policy makers journalists andthe interested public The GWPF is funded overwhelmingly by voluntarydonations from a number of private individuals and charitable trusts Inorder to make clear its complete independence it does not accept giftsfrom either energy companies or anyone with a significant interest in anenergy company

Viewsexpressed in thepublicationsof theGlobalWarmingPolicyFoun-dation are those of the authors not those of the GWPF its trustees itsAcademic Advisory Council members or its directors

Published by the Global Warming Policy Foundation

For further information about GWPF or a print copy of this reportplease contact

The Global Warming Policy Foundation55 Tufton Street London SW1P 3QLT 0207 3406038 M 07553 361717wwwthegwpforg

Registered in England No 6962749Registered with the Charity Commission No 1131448

• About the author
• Executive summary
• Introduction
• A conservation success story
• Fewer populations in decline
• Abrupt summer sea ice decline has not affected polar bear numbers as predicted
• Chukchi Sea population is thriving
• More prey means healthier polar bears
• Polar bears are adaptable
• Southern Beaufort numbers have rebounded
• Barents Sea numbers have increased
• Low sea ice in 2012 had no harmful effect on Southern Beaufort bear numbers
• Other species impacted by high polar bear numbers
• Western Hudson Bay population numbers are stable
• Hudson Bay sea ice is not changing much
• Problem bears in Churchill are not lean or starving
• Churchill Manitoba had the most problem bears in 1983 and 2016
• Marginal sea ice declines during the feeding period
• No evidence that subsistence hunting is affecting bear populations
• Stressful research methods have been curtailed
• No recent reports of polar bear cannibalism
• Polar bears appear unaffected by pollution
• Polar bears have survived past warm periods
• Conclusion
• Notes

GWPF BRIEFINGS1 Andrew Turnbull The Really Inconvenient Truth or lsquoIt Ainrsquot Necessarily Sorsquo2 Philipp Mueller The Greening of the Sahel3 William Happer The Truth about Greenhouse Gases4 Gordon Hughes The Impact of Wind Power on Household Energy Bills5 Matt Ridley The Perils of Confirmation Bias6 Philipp Mueller The Abundance of Fossil Fuels7 Indur Goklany Is Global Warming the Number One Threat to Humanity8 Andrew Montford The Climate Model and the Public Purse9 Philipp Mueller UK Energy Security Myth and Reality10 Andrew Montford Precipitation Deluge and Flood11 Susan Crockford On the Beach12 Madhav Khandekar Floods and Droughts in the Indian Monsoon13 Indur Goklany Unhealthy Exaggeration14 Susan Crockford Twenty Reasons not to Worry about Polar Bears15 Various The Small Print16 Susan Crockford The Arctic Fallacy17 Indur Goklany The Many Benefits of Carbon Dioxide18 Judith Curry The Climate Debate in the USA19 Indur Goklany The Papal Academiesrsquo Broken Moral Compass20 Donoughue and Forster The Papal Encyclical a Critical Christian Response21 Andrew Montford Parched Earth Policy Drought Heatwave and Conflict22 David Campbell The Paris Agreement and the Fifth Carbon Budget23 Various The Stern Review Ten Years of Harm24 Judith Curry Climate Models for the Layman25 Fritz Vahrenholt Germanyrsquos Energiewende a Disaster in the Making26 Hughes Aris Constable Offshore Wind Strike Prices27 Michael Miersch Truly Green28 Susan Crockford 20 Good Reasons Not to Worry About Polar Bears

TheGlobalWarming Policy Foundation is an all-party and non-party thinktank and a registered educational charity which while openminded onthe contested science of global warming is deeply concerned about thecosts and other implications ofmany of the policies currently being advo-cated

Our main focus is to analyse global warming policies and their economicand other implications Our aim is to provide themost robust and reliableeconomic analysis and advice Above all we seek to inform the mediapoliticians and the public in a newsworthy way on the subject in generaland on themisinformation towhich they are all too frequently being sub-jected at the present time

The key to the success of theGWPF is the trust and credibility thatwehaveearned in the eyes of a growing number of policy makers journalists andthe interested public The GWPF is funded overwhelmingly by voluntarydonations from a number of private individuals and charitable trusts Inorder to make clear its complete independence it does not accept giftsfrom either energy companies or anyone with a significant interest in anenergy company

Viewsexpressed in thepublicationsof theGlobalWarmingPolicyFoun-dation are those of the authors not those of the GWPF its trustees itsAcademic Advisory Council members or its directors

Published by the Global Warming Policy Foundation

For further information about GWPF or a print copy of this reportplease contact

The Global Warming Policy Foundation55 Tufton Street London SW1P 3QLT 0207 3406038 M 07553 361717wwwthegwpforg

Registered in England No 6962749Registered with the Charity Commission No 1131448

• About the author
• Executive summary
• Introduction
• A conservation success story
• Fewer populations in decline
• Abrupt summer sea ice decline has not affected polar bear numbers as predicted
• Chukchi Sea population is thriving
• More prey means healthier polar bears
• Polar bears are adaptable
• Southern Beaufort numbers have rebounded
• Barents Sea numbers have increased
• Low sea ice in 2012 had no harmful effect on Southern Beaufort bear numbers
• Other species impacted by high polar bear numbers
• Western Hudson Bay population numbers are stable
• Hudson Bay sea ice is not changing much
• Problem bears in Churchill are not lean or starving
• Churchill Manitoba had the most problem bears in 1983 and 2016
• Marginal sea ice declines during the feeding period
• No evidence that subsistence hunting is affecting bear populations
• Stressful research methods have been curtailed
• No recent reports of polar bear cannibalism
• Polar bears appear unaffected by pollution
• Polar bears have survived past warm periods
• Conclusion
• Notes

TheGlobalWarming Policy Foundation is an all-party and non-party thinktank and a registered educational charity which while openminded onthe contested science of global warming is deeply concerned about thecosts and other implications ofmany of the policies currently being advo-cated

Our main focus is to analyse global warming policies and their economicand other implications Our aim is to provide themost robust and reliableeconomic analysis and advice Above all we seek to inform the mediapoliticians and the public in a newsworthy way on the subject in generaland on themisinformation towhich they are all too frequently being sub-jected at the present time

The key to the success of theGWPF is the trust and credibility thatwehaveearned in the eyes of a growing number of policy makers journalists andthe interested public The GWPF is funded overwhelmingly by voluntarydonations from a number of private individuals and charitable trusts Inorder to make clear its complete independence it does not accept giftsfrom either energy companies or anyone with a significant interest in anenergy company

Viewsexpressed in thepublicationsof theGlobalWarmingPolicyFoun-dation are those of the authors not those of the GWPF its trustees itsAcademic Advisory Council members or its directors

Published by the Global Warming Policy Foundation

For further information about GWPF or a print copy of this reportplease contact

The Global Warming Policy Foundation55 Tufton Street London SW1P 3QLT 0207 3406038 M 07553 361717wwwthegwpforg

Registered in England No 6962749Registered with the Charity Commission No 1131448

• About the author
• Executive summary
• Introduction
• A conservation success story
• Fewer populations in decline
• Abrupt summer sea ice decline has not affected polar bear numbers as predicted
• Chukchi Sea population is thriving
• More prey means healthier polar bears
• Polar bears are adaptable
• Southern Beaufort numbers have rebounded
• Barents Sea numbers have increased
• Low sea ice in 2012 had no harmful effect on Southern Beaufort bear numbers
• Other species impacted by high polar bear numbers
• Western Hudson Bay population numbers are stable
• Hudson Bay sea ice is not changing much
• Problem bears in Churchill are not lean or starving
• Churchill Manitoba had the most problem bears in 1983 and 2016
• Marginal sea ice declines during the feeding period
• No evidence that subsistence hunting is affecting bear populations
• Stressful research methods have been curtailed
• No recent reports of polar bear cannibalism
• Polar bears appear unaffected by pollution
• Polar bears have survived past warm periods
• Conclusion
• Notes