how many reptiles are killed by cats in australia?reptiles in diet (n) % native reptiles/all...

How many reptiles are killed by cats in Australia

J C Z WoinarskiAJ B P MurphyA R PalmerB S M LeggeC C R DickmanDT S Doherty E G EdwardsF A NankivellG J L ReadH and D Stokeld I

ANESP Threatened Species Recovery Hub Research Institute for the Environment and LivelihoodsCharles Darwin University Casuarina NT 0909 Australia

BDepartment of Biodiversity Conservation and Attractions Locked Bag 104 Bentley Delivery CentreWA 6983 Australia

CNESP Threatened Species Recovery Hub Centre for Biodiversity and Conservation ResearchUniversity of Queensland St Lucia Qld 4072 Australia

DNESP Threatened Species Recovery Hub Desert Ecology Research Group School of Life and EnvironmentalSciences A08 University of Sydney NSW 2006 Australia

EDeakinUniversity School of Life and Environmental Sciences Centre for Integrative Ecology (BurwoodCampus)Geelong Vic 3220 Australia

FDepartment of Environment and Natural Resources PO Box 1120 Alice Springs NT 0871 AustraliaGNature Foundation SA Inc PO Box 448 Hindmarsh SA 5007 AustraliaHUniversity of Adelaide School of Earth and Environmental Sciences SA 5000 AustraliaIDepartment of Environment and Natural Resources Berrimah NT 0820 AustraliaJCorresponding author Email johnwoinarskicdueduau

AbstractContext Feral cats (Felis catus) are a threat to biodiversity globally but their impacts upon continental reptile faunas

have been poorly resolvedAimsToestimate thenumberof reptiles killedannually inAustralia bycats and to listAustralian reptile speciesknown to

be killed by catsMethodsWeused (1)data fromgt80Australian studies of cat diet (collectivelygt10 000 samples) and (2) estimates of the

feral cat population size to model and map the number of reptiles killed by feral catsKey resultsFeral cats inAustraliarsquos natural environments kill 466million reptiles yrndash1 (95CI 271ndash1006million) The

tally varies substantially among years depending on changes in the cat population driven by rainfall in inlandAustralia Thenumberof reptileskilledbycats is highest inarid regionsOnaverage feral cats kill 61 reptileskmndash2yearndash1 andan individualferal cat kills 225 reptiles yearndash1 The take of reptiles per cat is higher than reported for other continents Reptiles occur at ahigher incidence in cat diet than in the diet of Australiarsquos other main introduced predator the European red fox (Vulpesvulpes) Based on a smaller sample size we estimate 130million reptiles yearndash1 are killed by feral cats in highly modifiedlandscapes and 53million reptiles yearndash1 by pet cats summing to 649million reptiles yearndash1 killed by all cats Predation bycats is reported for 258Australian reptile species (about one-quarter of described species) including 11 threatened species

ConclusionsCat predation exerts a considerable ongoing toll onAustralian reptilesHowever it remains challenging tointerpret the impact of this predation in termsof populationviability or conservation concern forAustralian reptiles becausepopulation size is unknown formostAustralian reptile speciesmortality rates due to catswill vary across reptile species andbecause there is likely tobemarkedvariation among reptile species in their capability to sustain anyparticular predation rate

ImplicationsThis studyprovides awell grounded estimate of the numbers of reptiles killed by cats but intensive studiesof individual reptile species are required to contextualise the conservation consequences of such predation

Additional keywords conservation diet introduced predator island mortality predation

Received 10 November 2017 accepted 18 March 2018 published online 15 June 2018

Introduction

As with most other terrestrial vertebrate groups many reptilespecies across theworldhavedeclinedorbecomeextinct because

of invasive predator species with susceptibility especiallypronounced for island-endemic species (Boumlhm et al 2016Doherty et al 2016) However the impacts of introduced

CSIRO PUBLISHING

Wildlife Researchhttpsdoiorg101071WR17160

Journal compilation CSIRO 2018 wwwpublishcsiroaujournalswr

predators are generally not well resolved for continental reptilefaunas because there is little information on predation rates oron the effects of predation rates on the population viability ofany reptile species In Australia the significance of predationby introduced species upon reptiles is also difficult to evaluatebecause the reptile fauna is incompletely catalogued In additionpopulation trends for reptile species are difficult to discernbecause there are few substantial population monitoringprograms for reptiles (Meiri 2016 Meiri and Chapple 2016Woinarski 2018)Nonetheless recent studies havedemonstratedsevere impacts of introduced predators on at least localpopulations of some Australian reptiles For example highrates of predation on egg clutches by the introduced Europeanred fox (Vulpes vulpes) and pig (Sus scrofa) are implicatedin population declines of several species some threatenedof freshwater turtles (Spencer 2002 Spencer and Thompson2005 Fordham et al 2006 2008 Micheli-Campbell et al 2013Whytlaw et al 2013 Freeman et al 2014 Fielder et al 2015Robley et al 2016) and marine turtles (Limpus and Reimer1994) Predation by the red fox is also a recognised threat to somethreatened Australian lizard species (Nielsen and Bull 2016)Furthermore predation by the red fox has been implicated incomplex but substantial changes in some Australian reptilecommunities (particularly suppression of native reptilianpredators Olsson et al 2005 Sutherland et al 2011 Readand Scoleri 2015) Introduced predators probably primarilythe wolf snake (Lycodon capucinus) are also considered tohave caused the recent collapse of the endemic reptile faunaof theAustralian external territory of Christmas Island with fourof thefive native lizard species becoming extinct or extinct in thewild over the last decade (Smith et al 2012Andrew et al 2018)

Here we assess the extent of predation by the introducedhouse cat (Felis catus) on the Australian reptile fauna Catswere introduced to Australia at the time of European settlement(1788) and have since spread across the entire continent andonto most large islands (Abbott 2008 Abbott et al 2014 Leggeet al 2017) They have caused severe detrimental impacts onthe Australian mammal fauna (Woinarski et al 2015) and area major source of mortality for Australian birds (Woinarskiet al 2017a) There has been far less consideration of theirimpacts on the Australian reptile fauna The most substantialassessmentwaswithina recent studyofcontinental-scalevariationin the diet of feral cats (Doherty et al 2015) That study reportedthat (1) reptiles formed a significant component of the diet of cats(average frequency of occurrence 24 in cat dietary samples)(2) therewas substantial geographic variation in the occurrence ofreptiles in cat diet with a higher frequency of reptiles in cat dietarysamples from hotter drier areas and in mid-latitudes and (3) 157reptile species had been recorded within the diet of feral cats inAustralia including one threatened species the recently extinctChristmas Island forest skink (Emoia nativitatis)

Using a recent assessment of geographic variation in thedensity and hence total population size of feral cats inAustralia (Legge et al 2017) information on the number ofindividual reptiles within cat dietary samples (as distinct fromsimply the percentage occurrence of reptiles in dietary samples)and a more extensive compilation of cat diet information weextend the study of Doherty et al (2015) to evaluate the annualtally of reptiles killed by cats inAustralia and the spatial variation

in this number This study complements collates informationfrom many of the studies reported in and adopts a similaranalytical approach to a recent assessment of the number andspecies of birds killed by cats in Australia (Woinarski et al2017a 2017b) Our objectives are to (1) examine environmentaland geographical variation in the number of reptiles killed byferal cats (2) derive an overall estimate of the number of reptileskilled by feral cats annually (3) attempt to contextualise thisestimate in relation to the overall number of reptiles in Australia(4) compare these assessments with the number of birds killed inAustralia by cats (Woinarski et al 2017a) (5) compile anupdated inventory of Australian reptile species known to bekilled by feral cats (6) interpret the conservation consequencesand implications of these results and (7) compare these resultswith available information fromother continentsOurmain focusis on feral cats in largely natural environments but we alsoinclude some information on predation of reptiles by pet cats andby feral cats in highly modified environments

This assessment is of some global significance because theAustralian reptile fauna comprises more than 10 of theglobal reptile complement most Australian species (gt90)are endemic (Chapman 2009) and because the conservationmanagement of reptiles has been notably neglected globallycompared with other vertebrate groups (Roll et al 2017)

Methods

Feral cats in natural environments

To determine the numbers of feral cats in Australia and thespatial variation in cat density Legge et al (2017) collated andthen modelled 91 site-based estimates of feral cat density fromlargely natural sites widely and representatively scattered acrossAustralia They concluded that the total number of feral cats inlargely natural landscapes inAustralia was 207million (varyingbetween 14million in drought and average years to 56millionafter prolonged and extensive wet periods in inland Australia)

We collated 82 results from Australian studies (with aminimum of 10 cat scat or stomach samples per study) thatprovided a quantitative assessment of the frequency ofoccurrence of reptiles in cat stomachs or scats (Table 1) Thesestudies were widely spread across Australia (Fig 1) and includedbroad representation of Australian natural environments Intotal 32 of these studies were also included in a previousconsideration of continental variation in the diet of feral cats inAustralia (Doherty et al 2015) Where multiple studies providedestimates for the same location thesewere averaged (weighted bythe number of samples examined) Several individual studiesreported information from more than one site or from the samesite in markedly different conditions where the source data couldbe readily resolved to site level information from these separatesitesorconditionswas treatedasdistinctdatapoints inouranalyses(as per Table 1) such that the total number of study sitecombinations included in our analyses (98) exceeds the numberof included studies

Although the frequency of occurrence of reptiles in the diet offeral cats in Australia generally increases in warmer seasonsconsistent with seasonal variation in reptile activity (Paltridge2002 Yip et al 2015) it was not possible for us to account forseasonal variation in cat diet in this analysis becausemany of the

B Wildlife Research J C Z Woinarski

Table 1 Collation of accounts of the frequency of reptiles in the diet of feral cats in Australia (limited to those studies with gt10 samples)N sample sizeNG relevant information not given in source lsquoislandrsquo indicates island smaller than Tasmania Abbreviations forAustralian jurisdictions NSW

New South Wales NT Northern Territory Qld Queensland SA South Australia Tas Tasmania Vic Victoria WA Western Australia

Location frequency ofoccurrence ofreptiles indiet (N)

nativereptilesallreptilesin diet

Mean no ofindividualreptilesin sampleswith reptiles

Sampletype

Site type Source

Kanandah Nullarbor WA 421 (76) 100 NG Stomachs Mainland natural Algar and Friend (1995)Purple Downs SA 100 (14) 100 NG Stomachs Mainland natural Bayly (1976)Farina SA 550 (21) NG NG Stomachs Mainland natural Bayly (1978)Wedge Island Tas 15 (527) 100 NG Scats Island natural Beh (1995)East Gippsland Vic 45 (22) NG NG Scats Mainland natural Buckmaster (2011)Wet Tropics Qld 0 (123) NG NG Scats Mainland natural Burnett (2001)Gibson Desert WA 421 (19) NG NG Scats Mainland natural Burrows et al (2003)Various sites Tas 88 (45) NG NG Stomachs Mainland natural Cahill (2005)Yathong NSW 301 (112) 100 NG Stomachs Mainland natural Catling (1988)Collation across many sites Vic 25 (128) NG NG Stomachs Mainland natural Coman and Brunner (1972)Kakadu NT 80 (49) NG NG Scats Mainland natural Corbett (1995)Erldunda NT 553 (38) NG NG Stomachs Mainland natural Corbett (1995)Christmas Island 33 (92) NG NG Scats Island natural Corbett et al (2003)SW Wheatbelt WA 103 (39) NG NG Stomachs Mainland natural Crawford (2010)NingalooCape Range WA 40 (10) 100 300 Stomachs Mainland natural F Delanzy T Thomson and

M Vanderklift (unpubl)Dirk Hartog Island 714 (14) 100 NG Stomachs Island natural Deller et al (2015)Oberon NSW (natural area) 121 (33) NG NG Scats Mainland natural Denny (2005)Oberon NSW (rubbish dump) 83 (48) NG NG Scats Mainland modified Denny (2005)Tibooburra NSW (natural area) 458 (144) NG NG Scats Mainland natural Denny (2005)Tibooburra NSW

(rubbish dump)462 (119) NG NG Scats Mainland modified Denny (2005)

Dwellingup WA 71 (14) NG NG Stomachs Mainland natural C Dickman (unpubl)Katherine NT 414 (29) 100 275 Stomachs Mainland natural C Dickman (unpubl)Kellerberrin ndash Durokoppin WA 104 (48) 100 120 Stomachs Mainland natural C Dickman (unpubl)Mt Isa ndash Cloncurry Qld 462 (26) 100 217 Stomachs Mainland natural C Dickman (unpubl)Rottnest Island WA 219 (32) 100 114 Scats Island natural C Dickman (unpubl)Charles Darwin Reserve WA 463 (123) NG NG Scats Mainland natural Doherty (2015)Burt Plain NT 364 (33) 100 NG Stomachs Mainland natural G Edwards (unpubl)Daly Basin bioregion NT 182 (11) 100 NG Stomachs Mainland natural G Edwards (unpubl)Finke bioregion NT 348 (23) 100 NG Stomachs Mainland natural G Edwards (unpubl)Great Sandy Desert NT 250 (16) 100 NG Stomachs Mainland natural G Edwards (unpubl)Hamilton Downs NT 727 (187) NG NG Scats Mainland natural G Edwards (unpubl)MacDonnell Ranges NT 239 (109) 100 NG Stomachs Mainland natural G Edwards (unpubl)Mitchell Grass Downs NT 177 (192) 100 NG Stomachs Mainland natural G Edwards (unpubl)Pine Creek bioregion NT 71 (14) 100 NG Stomachs Mainland natural G Edwards (unpubl)Tanami NT 180 (61) 100 NG Stomachs Mainland natural G Edwards (unpubl)Irving Creek and Hale River NT 114 (35) NG NG Scats Mainland natural Foulkes (2002)Barrington Tops NSW 20 (49) NG NG Scats Mainland natural Glen et al (2011)Flinders Ranges SA 140 (50) NG NG Stomachs Mainland natural Hart (1994)Great Dog Island Tas 516 (91) 100 NG Scats Island natural Hayde (1992)Flinders Ranges SA

(before rabbit control)152 (70) 100 NG Stomachs Mainland natural Holden and Mutze (2002)

Flinders Ranges SA(post rabbit control)

131 (288) NG NG Stomachs Mainland natural Holden and Mutze (2002)

Anglesea Vic 06 (159) NG NG Scats Mainland modified Hutchings (2003)Karijini NP WA 170 (88) NG NG Scats Mainland natural Johnston et al (2013)Flinders Ranges SA 80 (60) NG NG Scats Mainland natural Johnston et al (2012)Flinders Ranges SA 292 (24) NG 129 Stomachs Mainland natural Johnston et al (2012)Macquarie Island Tas 0 (41) NG NG Stomachs Island natural Jones (1977)Macquarie Island Tas 0 (756) NG NG Scats Island natural Jones (1977)Mallee Vic 130 (131) NG NG Stomachs Mainland natural Jones and Coman (1981)Kinchega NP NSW 280 (65) NG NG Stomachs Mainland natural Jones and Coman (1981)Eastern Highlands Vic 30 (117) NG NG Stomachs Mainland natural Jones and Coman (1981)

(continued next page)

Reptiles killed by cats in Australia Wildlife Research C

Table 1 (continued )




Sampletype

Site type Source

Phillip Island Vic 50 (277) NG NG Stomachs Island natural Kirkwood et al (2005)Inland NE Qld 630 (169) 100 261 Stomachs Mainland natural Kutt (2011)Lambert station SW Qld 180 (49) NG NG Stomachs Mainland natural Lapidge and Henshall (2001)Mt Field and Tasman

Peninsula Tas0 (27) NG NG Stomachs Mainland natural Lazenby (2012)

Piccaninny Plains Qld 722 (18) NG 177 Stomachs Mainland natural McGregor et al (2016)northern Simpson Desert Qld 573 (377) NG NG Scats Mainland natural Mahon (1999)lsquoPastoralrsquo (mostly Pilbara

and Murchison) WA440 (50) 100 NG Stomachs Mainland natural Martin et al (1996)

lsquoRuralrsquo (mostly wheatbelt) WA 0 (31) NG NG Stomachs Mainland natural Martin et al (1996)Mitchell grass downs Qld 503 (187) 100 196 Stomachs Mainland natural Mifsud and Woolley (2012)Lake Burrendong NSW 34 (600) NG NG Scats Mainland natural Molsher et al (1999)Fitzgerald NP WA 195 (41) NG NG Stomachs Mainland natural OrsquoConnell (2010)Blackall Qld 467 (30) 100 NG Stomachs Mainland natural R Palmer (unpubl)Davenport Downs Qld 429 (184) 100 193 Scats and

stomachsMainland natural R Palmer (unpubl)

Denham Dump WA 453 (53) NG NG Scats Mainland modified R Palmer (unpubl)Diamantina Lakes Qld 560 (257) 100 NG Scats and


Great Western Woodlands WA 364 (11) 100 NG Scats Mainland natural R Palmer (unpubl)Inglewood Qld 45 (22) 100 NG Scats Mainland natural R Palmer (unpubl)Monkey Mia WA 421 (19) 100 NG Scats Mainland modified R Palmer (unpubl)Muncoonie Lakes

Birdsville Qld185 (27) 100 NG Scats Mainland natural R Palmer (unpubl)

Mulyungarie SA 350 (40) NG 221 Stomachs Mainland natural R Palmer (unpubl)North Kimberley WA 211 (19) 100 NG Scats Mainland natural R Palmer (unpubl)Offham SW Qld 435 (23) 100 200 Stomachs Mainland natural R Palmer (unpubl)Pannawonica WA 385 (13) 100 NG Scats Mainland natural R Palmer (unpubl)Kintore NT 629 (70) NG NG Scats Mainland natural Paltridge (2002)Tennant Creek

(Tanami Desert) NT724 (76) NG NG Scats Mainland natural Paltridge (2002)

Barkly Tablelands NT 170 (cA) NG NG Stomachs Mainland natural Paltridge et al (1997)Tanami NT 200 (bA) NG NG Stomachs Mainland natural Paltridge et al (1997)Watarrka NT 230 (aA) NG NG Stomachs Mainland natural Paltridge et al (1997)West (Pellew) Island NT 545 (11) NG 350 Scats Island natural Paltridge et al (2016)Simpson Desert NT 91 (44) NG NG Scats Mainland natural Pavey et al (2008)Roxby Downs SA 320 (127) NG NG Stomachs Mainland natural Pedler and Lynch (2016)Roxby Downs SA 294 (360) 100 262 Stomachs Mainland natural Read and Bowen (2001)Heirisson Prong WA 138 (109) NG NG Stomachs Mainland natural Risbey et al (1999)Sandford Tas 85 (47) NG NG Scats Mainland natural Schwarz (1995)Simpson Desert Qld 330 (42) NG NG Scats Mainland natural Spencer et al (2014)Kakadu NT 48 (84) NG NG Scats Mainland natural Stokeld et al (2016)Darwin NT (urbanrural) 56 (18) 100 100 Stomachs Mainland modified D Stokeld (unpubl)KakaduWardekken NT 348 (23) 100 163 Stomachs Mainland natural D Stokeld (unpubl)Top End NT 400 (10) 100 250 Stomachs Mainland natural D Stokeld (unpubl)Southern NT 545 (22) 100 142 Stomachs Mainland natural Strong and Low (1983)Christmas Island 310 (93) NG NG Scats and

stomachsIsland natural Tidemann et al (1994)

Croajingalong Vic 230 (48) NG NG Scats Mainland natural Triggs et al (1984)Armidale NSW 423 (26) 100 409 Scats Mainland natural van Herk (1980)Kosciuszko NSW 59 (17) NG NG Scats and

stomachsMainland natural Watson (2006)

Witchelina SA 631 (404) 100 305 Stomachs Mainland natural Woinarski et al (in press)Matuwa (Lorna Glen) WA 264 (337) NG NG Scats Mainland natural Wysong (2016)Western Qld (lsquoboomrsquo period) 230 (152) 100 146 Stomachs Mainland natural Yip et al (2015)Western Qld (lsquobustrsquo period) 600 (35) 100 290 Stomachs Mainland natural Yip et al (2015)

ASample sizes not given for separate areas in text but a + b + c = 390

D Wildlife Research J C Z Woinarski

constituent studies collated here spanned several seasons orthe time of year covered by the sampling was not specified Thestudies occurred over the period 1969ndash2017 but we do notinclude year in analyses as any directional trend in diet overdecadal scales is unlikely and Legge et al (2017) found noevidence of trends in cat densities over this period Inter-annualvariation in rainfall is a key driver of the abundance of manyspecies in arid and semiarid Australia including feral cats(Legge et al 2017) and we include separate analyses (for thenumber of reptiles killed by cats) based on modelled densitiesof cats in years of good rainfall in arid and semiarid Australiaand in years of poor or average rainfall there (Legge et al 2017)Inter-annual rainfall patterns in arid and semiarid Australiamay also influence the abundance of reptile species but theserelationships are more complex and vary among reptile species(Read et al 2012 Dickman et al 2014 Greenville et al 2016)

Collectively the collated cat dietary studies include 10 744samples of scats or stomachs Most studies reported onlyfrequency of occurrence (ie the proportion of stomachs orscats that contained reptiles) rather than a record of the numberof individual reptiles in those samples However in a subset ofthe studies (Table 1) tallies were given for the number ofindividual reptiles in those samples that contained reptilesWe assessed whether there was a relationship across studiesbetween the number of reptile individuals in those samples

that contained reptiles and the frequency of occurrence ofreptiles in those diet samples We modelled this relationshipusing a linear least-squares regression model of the form

log ethindividuals 1THORN frequency

Here we assume that that one stomach or scat samplerepresents 24 h worth of prey eaten by an individual cat Thisis likely to be a conservative under-estimate of the number ofprey killed per day because (1) prey are largely digested after12 h (2) cats typically produce more than one scat per day(3) cats may kill some reptiles but not necessarily consumethem (lsquosurplus killrsquo) (4) cats may injure hunted animalsbut not directly kill and consume them and many of thoseinjured animals will subsequently die and (5) reptile eggsand hatchlings may be rapidly digested and leave little trace(Hubbs 1951 Jackson 1951 George 1978 Davies and Prentice1980 Read and Bowen 2001 Jessup 2004 Loss et al 2013)Conversely cats may also scavenge so some reptiles includedin cat dietary studies are not necessarily killed by the cat thatconsumed them (Hayde 1992 Molsher et al 2017)

For analysis of the environmental (and other) factors thatmay have contributed to variation in the frequency of occurrenceand number of reptiles in cat samples we noted whether thestudy was from an island or the mainlands of Australia and

2500 mm

100 mm

Mean annual rainfall

Fig 1 Occurrence of cat dietary studies collated in this study There were 89 studies in natural vegetation(76 on the Australian mainland three in Tasmania and 10 on smaller islands including Macquarie andChristmas Islands not shown on map) There were another six studies in highly modified environments(such as rubbish dumps) The map background shows mean annual rainfall (Australian Bureau ofMeteorology 2016b) The dashed line indicates the Tropic of Capricorn

Reptiles killed by cats in Australia Wildlife Research E

Tasmania (64 519 km2) and ndash if on an island ndash the size of theisland We derived a composite variable expressing whetherthe site was an island and the size of the island

island size index frac14 log10 minimum 1area

10 000

n o

where area is landmass or island area in km2 Therefore any landmass or island with area 10 000 km2 (ie the Tasmanian andAustralian mainlands) has an index of 0 Islands lt10 000 km2

have negative values which become increasingly negativewith decreasing island area From the reported location of thestudy we also determined mean annual rainfall (AustralianBureau of Meteorology 2016b) mean annual temperature(Australian Bureau of Meteorology 2016a) mean tree coverwithin a 5-km radius (Hansen et al 2003) and topographicruggedness (standard deviation of elevation within a 5-kmradius) (Jarvis et al 2008)

We used generalised linear modelling to examine geographicvariation in the frequency of occurrence of reptiles in the diet offeral cats The response variable was a proportion (number ofsamples containing reptiles out of the total number of samples)and thus was analysed using the binomial error family Weexamined a set of 40 candidate models representing allcombinations of the five explanatory variables described above(island size index rainfall temperature tree cover ruggedness)including an interaction between rainfall and temperature (toaccount for a possible negative effect of temperature on wateravailability) Models were evaluated using a second-order formof Akaikersquos Information Criterion (QAICc) which is appropriatefor small sample sizes and overdispersed data (Burnham andAnderson 2003) There was evidence of strong overdispersionso we used the lsquoquasibinomialrsquo error structure to estimatecoefficient standard errors and confidence intervals

The final model was based on multi-model averaging of theentire candidate set with each model weighted according to withe Akaike weight equivalent to the probability of a particularmodel being thebest in the candidate set (BurnhamandAnderson2003) The final model was used to predict the frequency ofoccurrence of reptiles in cat diet across Australiarsquos naturalenvironments (ie excluding areas of intensive land use suchasurbanareas and rubbishdumps followingLeggeet al (2017))

The predicted frequency of occurrence of reptiles in catdiets was used to estimate the number of individual reptiles inthose cat samples that contained reptiles using the linear least-squares regression model described earlier (log [individuals ndash 1]~frequency) We multiplied the predicted frequency ofoccurrence of reptiles in cat samples across Australia by thepredicted number of individual reptiles in those cat sampleswith reptiles which provided a spatial representation of theestimated number of reptiles killed per feral cat per day Thisresult was multiplied by the modelled density of cats in naturalenvironments across Australia (Legge et al 2017) and then by36525 (days in a year) to provide a spatial representation ofthe estimated number of reptiles killed by cats kmndash2 yearndash1 Wesummed this rate across the natural environments of Australiato derive the total number of reptiles killed by feral cats

We followed the approach of Loss et al (2013) and Leggeet al (2017) and characterised the uncertainty of the estimatedtotal number of reptiles killed by feral cats using bootstrapping

Bootstrapping is an appropriate approach because we neededto propagate errors through several analytical steps (eg theestimate of the total feral cat population the number of reptileseaten per cat per year) We simultaneously bootstrapped (20 000times) the three underlying datasets (1) cat density (2) frequencyof reptiles in cat diet samples and (3) the number of individualreptiles in cat diet samples containing reptiles For each randomselection of these underlyingdatawe recalculated the total numberof reptiles killed We report the 25 and 975 quantiles forthe 20 000 values of the total number of reptiles killed

Based on studies that included identification of reptilespecies in cat dietary items we also calculated the meanpercentage of reptile items consumed that were native speciesFrom all studies that reported the total number of individualreptiles in cat samples and the taxonomic identity (to familygenus or species) we also calculated the percentage of cat-killedreptiles by broad reptile group crocodiles (family Crocodylidae)marine turtles (Cheloniidae and Dermochelyidae) freshwaterturtles (Carettochelydidae and Chelidae) geckoes(Carphodactylidae Diplodactylidae Gekkonidae) pygopodids(Pygopodidae) agamids (Agamidae) skinks (Scincidae)monitors (Varanidae) blind snakes (Typhlopidae) pythons(Boidae) file snakes (Acrochordidae) colubrid snakes(Colubridae) or elapid snakes (Elapidae)

Feral cats in highly modified landscapes

Legge et al (2017) estimated that there are 072million feralcats occurring in the ~57 000 km2 of Australia that comprisehighly modified landscapes (such as rubbish dumps intensivepiggeries urban areas) where food supplementation for feralcats is unintentionally provided by humans There were only sixAustralian studies (with gt10 samples) that reported frequency ofreptiles in the diet of feral cats occurring in highly modifiedenvironments (Table 1) This small number provides little scopefor assessing variability so we simply use the average frequencyof occurrence of reptiles in samples across these six studies andmultiply this mean by the expected number of individual reptilesin cat samples with that frequency and then by the density (andhence population size) of feral cats in these environments asestimated byLegge et al (2017)We also compare the frequencyof reptiles in these samples with those from feral cats in naturalenvironments using MannndashWhitney U-tests but note that thesmall sample size of dietary studies for cats in highly modifiedenvironments constrains the reliability of such comparisons

Pet cats

From national surveys of pet ownership the population of petcats in Australia has been previously estimated at 388million(Animal Medicines Australia 2016) The average number ofreptiles killed by pet cats in Australia has been estimated inseveral studies that have involved cat owners tallying the numberof prey items brought in by pet cats over fixed time periods(Paton 1990 Paton 1991 Paton 1993 Trueman 1991 Barratt1997 Barratt 1998) There is substantial variation in such talliesaccording to the amount of time the pet cat is allowed to roamoutside (Trueman 1991)

The actual number of kills by pet cats is likely to beappreciably higher than these owner-reported tallies given

F Wildlife Research J C Z Woinarski

that studies elsewhere indicate that pet cats typically returnhome with a relatively small proportion of prey actually taken(Blancher 2013) with estimates of this proportion from studieson other continents being 125 (Maclean 2007) 23 (Loydet al 2013) and 30 (Kays andDeWan2004) Herewe averageacross Australian studies the number of individual reptilesreported by pet owners to be killed by their pet cats per yearand scale this up to account for the number of reptiles killed butnot returned to the catrsquos home using the mean (22) from thethree studies that provide estimates of this proportion

Comparison of frequency of reptiles in the diet of feral catswith that of other co-occurring mammalian predators

Australian reptiles face many introduced and native predators inaddition to cats A subset of the feral cat diet studies collated herealso included comparable sampling of the diet of other co-occurring mammalian predators notably the introduced redfox and dingo (including wild dog) (Canis dingofamiliaris)For studies that included at least 10 samples of feral cats and atleast 10 samples of one other mammalian predator species wecompared the frequency of reptiles in samples using Wilcoxonmatched-pairs tests

List of reptile species reported to be killed by feral cats

From a collation of individual cat dietary studies Doherty et al(2015) derived a list of Australian reptile species known to bekilled by feral cats We add to that list by incorporatinginformation from additional cat dietary studies autecologicalstudies of reptiles and specimens reported as cat-killed from allmain museums in Australia There are some notable caveats andbiases in constructing such a list First the Australian reptilefauna has been subjected to major taxonomic overhaul in recentdecades resulting inter alia in a rapid increase in the number ofdescribed species (Oliver et al 2009 Cogger 2014Meiri 2016)therefore specific names given for reptiles in older studies maynow be difficult to reconcile unambiguously with the currentlyrecognised taxonomy Second diagnostic morphologicalcharacteristics for reptile species in some groups (eg manysmall skinks blind snakes) are difficult enough to resolve in thefieldwith intact specimens but suchfine species-level resolutionwill be impossible in many circumstances for the partly digestedand fragmented material within cat stomachs or ndash even morechallenging ndash from reptile scales and skeletal residue in cat scatsthusmany reptiles in cat dietary samples have been listed only tofamily or genus level Third many reptile species have highlylocalised ranges (Rosauer et al 2016 Oliver et al 2017) andtheremayhave beenno sampling of cat diet in the small areas thatsuch species occupy

We also report the conservation status of reptile speciesrecorded to be killed by cats although we note that conservationstatus has not yet (as at February 2018) been completed for mostAustralian species (Boumlhm et al 2013 Meiri and Chapple 2016)

Results


Based on 89 estimates from natural environments in Australia(Table1Fig 1) theoverall frequencyofoccurrenceof reptiles incat scat and stomach samples was 256 (95CI 210ndash307)

with frequency ranging widely across individual studies from0 to 100

Generalised linear modelling suggested that two variableswere clear predictors of the frequency of reptiles in feral cat dietsamples mean annual rainfall (with higher frequency of reptilesin cat samples in areas of lower rainfall) and mean annualtemperature (with higher frequency of occurrence in areas ofhigher temperature) (Fig 2) These variables were included inthe 17 most highly ranked models all with a very high level ofsupport (QAICc lt149 Table 2) The best models had R2 of056 Other variables (whether the sample was from an island

0

20

40

60

80

100

0 5 10 15 20 25 30

Mean annual temperature (degC)

0

20

40

60

80

100

0 1000 2000 3000

Fre

quen

cy o

f rep

tiles

in c

at d

iets

(

)

Mean annual rainfall (mm)

(a)

(b)

Fig 2 Variation in the frequency of reptiles in cat samples in relationto (a) mean annual rainfall and (b) mean annual temperature in AustraliaObservations from the mainland comprising Tasmania and greaterAustralian mainland are indicated by filled circles while those fromislands smaller than Tasmania (64 519 km2) are indicated by unfilledcircles Regression lines represent the predictions of generalised linearmodels (quasibinomial errors) with 95 confidence intervals

Reptiles killed by cats in Australia Wildlife Research G

or mainland topographic ruggedness or tree cover) had littleinfluence on the frequency of reptiles in cat diet Thesemodelledrelationships were used to project the frequency of reptiles in catdiets across Australia (Fig 3a)

The number of individual reptiles in cat dietary samples thatcontained reptiles was correlated with the frequency of reptilesin cat samples (Fig 4) ie when a high proportion of the catsamples in a study contained reptiles each of those sampleswith reptiles was likely to include many individual reptilesThere were many notable cases of high numbers of individualreptiles in single cat stomachs including 24 individual reptilesin a single cat stomach (Muir 1982) 40 (including 34Tympanocryptis lineata) and 21 individual reptiles (including15 T lineata) (Brooker 1977) at least 19 skinks (Jones andComan 1981) 32 (including 24 Ctenophorus pictus) 22 and19 reptile individuals (Read and Bowen 2001) 27 individualskinks (all Pseudomoia pagenstecheri) (Cahill 2005) 20individual skinks (all Ctenotus regius) (Bayly 1976) and 3318 and 17 individual reptiles (Woinarski et al in press)

Spatial analyses revealed a clear contrast in the relativenumbers of reptiles killed per km2 between mesic coastalAustralia (with relatively low numbers of reptiles killed witha minimum of 01 kmndash2 yearndash1) and arid and semiarid areasof the Australian interior (with relatively high kill rates toa maximum of 219 kmndash2 yearndash1) (Fig 3b)

Summing these rates provides an estimate of 466millionreptiles (95 CI 271ndash1006million) killed by feral cats acrossthe natural environments of Australia per year (varying from250million (95 CI 168ndash501million) in dry or average yearsto 149 billion in wet years (95 CI 058ndash356 billion))(Fig 5a) On average a feral cat kills 225 reptiles per year(95 CI 157ndash344) (Fig 5b) The average number of reptileskilled by feral cats in natural environments is 611 kmndash2 yearndash1

(95 CI 355ndash1318) varying from 327 kmndash2 yearndash1 (95 CI220ndash656) in dry and average years to 1947 kmndash2 yearndash1 (95CI 762ndash4660) in wet years

For the 41 studies where all the species of reptiles present incat dietary sampleswere reported all reptile specieswere nativeHowever two studies fromChristmas Island (Corbett et al 2003Tidemann et al 1994) reported some occurrence of introducedreptile species in cat diet but information presented in thosestudies did not allow the calculation of a proportion of all cat-killed reptiles that was native Given that the two ChristmasIsland studies are atypical in sampling an area with a relativelyhigh proportion of introduced reptiles and that introduced reptilespecies are absent frommost sites in studies where reptiles in catdiet samples were not identified to species it is highly likely thatnative reptile species in the diet of feral cats comprise close to100 of all reptiles consumed across most of Australia

Reptiles killed by cats are taxonomically diverse Acrosscat dietary studies that reported the identity and number of allreptiles killed (Table 3) skinks (350) agamids (303) andgeckoes (215) comprised the largest proportions of cat-killed reptile individuals Pygopodids (16) goannas (35)blind snakes (18) pythons (01) colubrid snakes (01) andelapid snakes (62) comprised smaller proportions and thesestudies reported no crocodiles marine turtles freshwater turtlesorfile snakes in the cat dietary samples (Table 3) ndash although thereare records of cats consuming freshwater turtles and hatchlingmarine turtles in other studies that provided less quantitativedescriptions of cat diet (Supplementary Table S1) There wassubstantial variation among studies in the relative proportions ofdifferent reptile families killed by cats (Table 3)


Of the six studies that reported the frequency of occurrence ofreptiles in samples from feral cats in highly modifiedenvironments (Table 1) the mean frequency of occurrence ofreptiles was 247 similar to and not significantly differentfrom that for cats in largely natural environments (mean 256MannndashWhitney U-test z= 047 P= 064) Multiplying thereptile frequency in the six studies by the expected number ofreptile individuals in sampleswith reptiles (relationship shown inFig 4) by 36525 (days in a year) and then by the total populationsize of feral cats in highly modified landscapes (072 millionLegge et al (2017)) produces an estimate of 1300millionreptiles killed per year by feral cats in modified environments

Pet cats

Pet owners reported an average of 78 reptiles observed to betaken home as prey per cat per year in Adelaide from a sample of166 cats (with the highest rates of predation of reptiles by pet catsin rural areas followed by country towns and then suburbs)(Paton 1991) In comparable studies pet owners in Canberrareported an average of 06 reptiles taken home as prey per catper year from a sample of 138 cats (Barratt 1998) and those inHobart reported an average of 06 reptiles per year from a sampleof 166 cats (Trueman 1991) Using the average of 30 reptilesobserved to be taken per cat per year across these studies andscaling this mean by the average proportion of all kills that arereturned home (ie 22) the average number of reptiles killed

Table 2 Models explaining variation in frequency of reptiles in catdiets in natural environments throughout Australia and the results of

the model selection procedureThe models are shown ranked in ascending order of the model selectioncriterion DQAICc which is the difference between the modelrsquos QAICc

value and the minimum AICc value in the candidate set wi is the Akaikeweight or the probability of the model being the best in the candidate setModels that are well supported relative to the null model (within 2 QAICc

units) are shaded grey models with limited support (DQAICc gt5) or lowersupport than the null model are not included in the table

Model DQAICc wi R2

~log10 (rainfall) + temperature 00 029 056~log10 (rainfall) temperature 15 014 057~log10 (rainfall) + temperature + tree cover 21 010 056~log10 (rainfall) + temperature + ruggedness 23 009 056~island size index + log10 (rainfall) + temperature 23 009 056~log10 (rainfall) temperature + tree cover 37 005 057~log10 (rainfall) temperature + ruggedness 38 004 057~island size index + log10 (rainfall) temperature 38 004 057~island size index + log10 (rainfall) + t

emperature + tree cover44 003 056

~log10 (rainfall) + temperature + treecover + ruggedness

44 003 056

~island size index + log10 (rainfall) +temperature + ruggedness

46 003 056

H Wildlife Research J C Z Woinarski

60

10

150 reptiles kmndash2 yearndash1


(a) Frequency of reptiles inferal cat diets

(b) Number of reptiles eatenby feral cats

Fig 3 Model projections of (a) the frequency of reptiles in cat diets and (b) the number of reptiles killed bycats each year in natural environments throughout Australia For (a) predictor variables in the regressionmodel aremean annual rainfall mean annual temperature tree cover and ruggedness weighted according toAkaike weights (wi) for the candidate models (Table 2) The dashed lines indicate the Tropic of Capricorn

Reptiles killed by cats in Australia Wildlife Research I

by individual pet cats is 136 yearndash1 Hence with a totalAustralian population of 388million pet cats the estimatedannual tally of reptiles killed by pet cats is 529million Wenote the marked disparity in estimated rates of predation by petcats on reptiles between the studies by Paton (1991) and those byBarratt (1998) and Trueman (1991) and thus attach lowconfidence to our collated tally

Comparison of frequency of occurrence of reptiles in the dietof feral cats with that of other co-occurring mammalianpredators

Comparative data on the frequency of occurrence of reptiles insamples of feral cats and other co-occurring mammalianpredators are summarised in Table 4 Across 24 studies wherethe diet of co-occurring cats and foxes was reported thefrequency of occurrence of reptiles was appreciably higher inthe diet of cats (mean = 311) than of foxes (mean = 200)(Wilcoxon-matched-pairs test z= 346 P= 00005) Across 18studies in which the diet of co-occurring cats and wild dogs(including dingoes)was reported the frequency of occurrence ofreptiles in the diet of cats (263) was higher than that of dogs(161) but not significantly so (z= 150 P= 014) Only twostudies with sample sizes of gt10 samples per predator specieshave considered the diet of cats and a co-occurring nativemarsupial predator in both cases the spotted-tailed quollDasyurus maculatus (Burnett 2001 Glen et al 2011) In thesestudies the frequency of reptiles was low in both species (meanof 10 for cats and 39 for quolls)

Reptile species reported to be killed by feral cats

Wecollated recordsof 258Australian reptile species known tobekilled by cats (Supplementary Table S1) a substantial increasefrom the 157 species previously reported by Doherty et al(2015) This tally represents about a quarter of the describedAustralian terrestrial reptile fauna (997 species are listed in

Supplementary Table S1 which excludes sea snakes) andincludes representation of all families with primarilyterrestrial species Varanidae had the highest proportion(47) of species reported in cat diets possibly because theseare relatively large lizards and are readily identifiable to speciesin cat dietary samples Species known to be killed by catscomprised 10ndash30 of the species complement for most otherterrestrial families

Although there is insufficient information in the collatedsources to report on species-level impacts of cat predationsome reptile species have been reported as cat prey frommany studies the tree dtella (Gehyra variegata) Bynoersquosprickly gecko (Heteronotia binoei) central bearded dragon(Pogona vitticeps) robust ctenotus (Ctenotus robustus)broad-banded sand-swimmer (Eremiascincus richardsonii)and curl snake (Suta suta) have all been reported as cat preyin at least 10 studies describing cat diet This may be becausethese species are targeted by cats they are common andwidespread andor relatively many cat dietary studies havebeen undertaken within their range

The list of cat-killed reptile species includes four of the 31Australian terrestrial squamate species listed as threatened by theIUCN (as at February 2018) ndash (1) the Christmas Island forestskink (2)dwarf copperhead (Austrelaps labialis) (3)LordHowe

0

1

2

3

4

5

6

0 20 40 60 80

Indi

vidu

al r

eptil

es p

er d

iet s

ampl

e

Frequency of reptiles in cat diets ()

Fig 4 The modelled relationship between the number of individualreptiles in those samples containing reptiles and the frequency (incidence)of reptiles in cat dietary samples according to a linear least-squaresregression model of the form log (individuals ndash 1) ~frequency

0

5

10

15

20

25

30

35

0 800 1600 2400 3200 4000

Fre

quen

cy (

)

Total number of reptiles eaten by feral cats (M reptiles yearndash1)

0

3

6

9

12

0 100 200 300 400

Fre

quen

cy (

)

Reptiles eaten by each feral cat (reptiles catndash1 yearndash1)

Dryndashaverage periods onlyAll observations

Wet periods only

(a) Total number of reptiles eaten

(b) Number of reptiles eaten by each feral cat

Fig 5 Uncertainty in (a) the total number of reptiles eaten and (b) thenumber of reptiles eaten by each feral cat based on bootstrapping of thedataset 20 000 times At the top of each panel is the mean (filled circle)and 95 confidence bounds (lines) In (a) this is shown separately foranalyses with cat density observations from wet periods dryndashaverageperiods and including all observations (wet and dryndashaverage) (as definedin Legge et al 2017)

J Wildlife Research J C Z Woinarski

Tab

le3

Percentag

eof

allreptile

siden

tified

incatdietarysamplesb

yreptile

family

for

stud

iesrepo

rtingtheiden

tity

andnu

mbe

rsof

allreptile

sconsum

edby

feralcats

lsquoFreqOccrsquo

isthe

ofcatsamples

that

contained

reptileslsquoN

oreptilesrsquois

thetotalnu

mberof

reptileindividu

alsrepo

rted

incatdietary

samples

inthestud

yReptile

families

Gecko

es(C

arph

odactylidae

DiplodactylidaeGekko

nidae)Pyg

op(Pyg

opod

idae)

Agam(A

gamidae)

Scinc(Scincidae)

Varan(V

aranidae)

Typ

hl(Typ

hlop

idae)

Colub

(C

olub

ridae)Boid

(Boidae)

Elap

(Elapidae)N

otethat

none

ofthelisted

stud

iesinclud

edcrocod

ilesm

arineor

freshw

ater

turtlesor

file

snakes

ascatdietaryitem

s

Location

Sou

rce

Freq

Occ

No

reptiles

Gecko

esPyg

op

Agam

Scinc

Varan

Typ

hl

Colub

Boid

Elapid

Wedge

Island

Tas

Beh

(199

5)15

800

00

00

1000

00

00

00

00

00

NingalooCapeRangeW

ADelanzyT

hompson

and

Vanderkift(unp

ubl)

400

1266

783

00

83

167

00

00

00

00

MtIsaQld

Dickm

an(unp

ubl)

462

2611

538

308

346

00

38

00

00

154

Katherine

ndashVRDN

TDickm

an(unp

ubl)

414

3339

461

30

455

00

30

00

00

30

RottnestIsland

WA

Dickm

an(unp

ubl)

219

1010

000

00

700

00

00

00

00

20KellerberrinndashDurok

oppin

WA

Dickm

an(unp

ubl)

104

600

00

333

667

00

00

00

00

00

Dwelling

upW

ADickm

an(unp

ubl)

71

100

00

00

1000

00

00

00

00

00

GreatDog

Island

Tas

Hayde

(199

2)51

647

00

00

00

936

00

00

00

00

64

Flind

ersRangesSA

John

ston

etal(20

12)

292

900

00

00

1000

00

00

00

00

00

Phillip

Island

Vic

Kirkw

oodet

al(20

05)

50

2000

00

00

1000

00

00

00

00

00

Inland

NEQld

Kutt(201

1)63

027

735

722

343

155

51

00

00

04

69

Picanniny

PlainsQld

McG

rego

ret

al(20

16)

722

2387

00

217

739

00

00

00

00

00

Mitchellgrassdo

wnsQ

ldMifsudandWoo

lley

(201

2)50

313

192

23

519

206

00

23

00

00

137

OffhamQ

ldPalmer

(unp

ubl)

435

2030

000

150

450

50

00

00

00

50

BlackallQld

Palmer

(unp

ubl)

467

2763

000

185

37

00

00

00

00

148

Mulyu

ngarieQ

ldPalmer

(unp

ubl)

350

3154

800

161

32

00

00

00

00

129

West(Pellew)Island

NT

Paltridge

etal(20

16)

545

2195

00

333

476

00

00

48

00

48

Rox

byDow

nsS

AReadandBow

en(200

1)29

430

521

607

249

456

33

23

00

00

16

Heirisson

Prong

WA

Risbeyet

al(19

99)

138

1533

300

333

333

00

00

00

00

00

Arm

idaleNSW

vanHerk(198

0)42

325

120

00

40

840

00

00

00

00

00

WitchelinaSA

Woinarski

etal(in

press)

631

442

174

16

348

305

57

38

00

02

59

Western

Qld

(boo

mperiod

)Yip

etal(20

15)

230

5080

20

600

220

20

00

00

00

60

Western

Qld

(bustperiod

)Yip

etal(20

15)

600

5413

037

315

333

37

00

00

00

148

Totals

1588

342

2548

155

55

281

299

Reptiles killed by cats in Australia Wildlife Research K

Island skink (Oligosoma lichenigera) and (4) great desertskink (Liopholis kintorei) ndash as well as eight of the 45terrestrial squamate species listed as threatened nationallyunder Australiarsquos Environment Protection and BiodiversityConservation Act 1999 (as at February 2018) and one marineturtle and one freshwater turtle listed as threatened nationally(Supplementary Table S1)

Discussion

We provide the most robust estimate to date on the extentof and geographic variation in continental-scale predation ofreptiles by an introduced species That take is substantial feralcats in Australiarsquos largely natural environments kill more thanone million reptiles per day and individual cats take onaverage more than 225 individual reptiles yearndash1 with almostall of these killed reptiles being native species (consistent withthe generally low proportion of non-native to native reptilesin most parts of Australia)

The incidence of predation on reptiles by feral cats showsmarked geographic variation being significantly higher in hotterand drier regions consistent with results reported by Dohertyet al (2015) Given that cat density also tends to be higher inarid Australia at least in wetter seasons (Legge et al 2017) thetotal number of reptiles killed by cats per unit area increasesby at least an order of magnitude from Australiarsquos higherrainfall coastal fringe to inland deserts Although there is littlecomparable information on geographic variation in the densityof reptiles variation in numbers of reptiles killed by cats isbroadly consistent with patterns in the species richness of theAustralian reptile fauna with species richness highest formany groups in more arid areas (Pianka 1969 1981 1989Morton and James 1988 Powney et al 2010 Cogger 2014)with some indication that density of reptiles is also highest inarid areas of Australia (Read et al 2012)

The only previous estimate of the numbers of reptiles killedby cats per area or per year for any site in Australia is that ofRead and Bowen (2001) for a site (Roxby Downs) in arid South

Table 4 Australian studies reporting the frequency () of reptiles in the diet of cats and co-occurring mammalian predatorsStudies are included only where at least 10 samples were reported for cats and at least one other predator The sample size is given in parentheses

Co-occurring predators Location SourceFeral cat Fox Dogdingo Spotted-tailed quoll

550 (21) 107 (29) Farina SA Bayly (1978)00 (123) 15 (282) 22 (1252) Wet Tropics Qld Burnett (2001)421 (19) 410 (22) Gibson Desert WA Burrows et al (2003)301 (112) 233 (288) Yathong NSW Catling (1988)553 (38) 114 (44) 119 (285) Erldunda NT Corbett (1995)463 (123) 54 (37) Charles Darwin reserve WA Doherty (2015)114 (35) 00 (26) 55 (310) Irving Creek and Hale River NT Foulkes (2002)20 (49) 126 (95) 29 (68) 56 (168) Barrington Tops NSW Glen et al (2011)140 (50) 17 (105) Flinders Ranges SA Hart (1994)131 (288) 95 (774) Flinders Ranges SA

(post rabbit control)Holden and Mutze (2002)

170 (88) 466 (73) Karijini NP WA Johnston et al (2013)30 (117) 60 (166) Eastern Highlands Vic Coman (1972) Jones and Coman (1981)50 (277) 00 (147) Phillip Island Vic Kirkwood et al (2005)180 (49) 25 (38) SW Qld Lapidge and Henshall (2001)573 (377) 366 (382) Simpson Desert Qld Mahon (1999)503 (187) 250 (52) Mitchell Grass Downs Qld Mifsud and Woolley (2012)34 (600) 92 (261) Lake Burrendong NSW Molsher et al (1999)

Molsher et al (2000)101 (217) 336 (756) Astrebla Downs Qld R Palmer (unpubl)429 (184) 179 (28) Davenport Downs Qld R Palmer (unpubl)364 (11) 278 (18) 29 (105) Great Western Woodlands WA R Palmer (unpubl)45 (22) 38 (53) Inglewood Qld R Palmer (unpubl)185 (27) 234 (64) Muncoonie Lakes Birdsville Qld R Palmer (unpubl)435 (23) 365 (74) Offham SW Qld R Palmer (unpubl) Palmer (1995)385 (13) 00 (50) Pannawonica WA R Palmer (unpubl)629 (70) 657 (70) Kintore Paltridge (2002)724 (76) 491 (53) 766 (77) Tennant Creek Paltridge (2002)91 (44) 32 (63) 228 (316) Simpson Desert NT Pavey et al (2008)294 (360) 190 (105) Roxby Downs SA Read and Bowen (2001)138 (109) 21 (47) Heirisson Prong WA Risbey et al (1999)311 (254) 182 (572) 263 (236) Simpson Desert Qld Spencer et al (2017)48 (84) 01 (1100) Kapalga NT Stokeld et al (2016)230 (48) 30 (937) 30 (412) Croajingalong Vic Triggs et al (1984)631 (404) 686 (51) 00 (11) Witchelina SA Woinarski et al (in press)264 (337) 25 (353) Matuwa (Lorna Glen) Wysong (2016)

L Wildlife Research J C Z Woinarski

Australia They estimated a feral cat density there of 2 kmndash2and average kill rate by individual cats of 350 reptileindividuals yearndash1 thus concluding that feral cats in that areaconsumed 700 individual reptiles kmndash2 yearndash1 These estimatesare somewhat higher than our modelled estimates for aridAustralia with cat density in that study notably higher thantypical values reported in Legge et al (2017)

Our focus was primarily on the numbers of reptiles killedby feral cats in natural environments and most of the evidencethat we collated refers to this component of the Australian catpopulation With much less evidence we also estimated thenumbers of reptiles killed by pet cats at 53million yearndash1 and byferal cats in highly modified environments at 130million yearndash1hence summing to 649million reptiles yearndash1 (ie ~18millionreptiles dayndash1) killed by all components of the Australian catpopulation

It is difficult to contextualise and interpret our estimatesof the annual take of Australian reptiles by cats in terms ofconservation impact consequences to the population viabilityof any reptile species or relative to other causes of reptilemortality because very few studies have assessed suchparameters (Braysher 1993) There are remarkably few studiesthat provide robust information on population size or densityfor any Australian reptile species or the overall density ofreptiles At an arid site in South Australia Read et al (2013)used markndashrecapture analyses to estimate densities for sixcommon reptile species (of skinks and geckoes) with thesevarying from 85 to nearly 400 individuals handash1 Ehmann andCogger (1985) collated the few available density estimatesfor individual Australian reptile species across a broaderenvironmental range and Cogger et al (2003) used these toestimate that the average density (across all reptile species) inAustralia was 200 individual reptiles handash1 giving a national tallyof 154 000million reptiles These are clearlybold extrapolationsbut they are the only available estimates of density and the totalnumbers for Australian reptile assemblages Albeit recognisingthe meagre evidence base these tallies indicate that cats kill~04 of Australian reptiles per year

Cogger et al (2003) also provided an estimate for one othermajor source of reptile mortality in Australia the number ofreptile individuals killed by land clearing Based on theirestimates of average reptile density and a then-annual rate ofvegetation clearance of ~4500 km2 in Queensland (theAustralian state with highest rate of loss of native vegetation)they concluded that this clearing resulted in the loss of 89millionindividual reptiles per year The national rate of deforestationhas declined unevenly since then and in 2013ndash14 was~2000 km2 yearndash1 (Evans 2016) However deforestation inQueensland increased again in 2015ndash16 with 40millionreptiles estimated to be killed there in each of those years(Cogger et al 2017) These annual rates of loss of reptilesdue to habitat clearance are appreciably less than ourestimates of the numbers of reptiles lost annually to catpredation (~649million) However we recognise that such acomparison has interpretational constraints clearing results inpermanent loss of habitat suitability and reduction in reptiledensity whereas a larger annual tally of reptiles killed due to catpredation may have far less acute or longer-term impact onindividual reptile species or communities than habitat loss

Our collation includes records of more than 250 Australianreptile species killed by feral cats including10species nationallylisted as threatened The actual number of reptile species killedby cats is likely to be appreciably higher than this tally given thatmany cat dietary studies have not reported reptile prey to specieslevel many Australian reptile species are highly localised andthere have been no cat dietary studies in many parts of AustraliaCats consumeabroad taxonomic spectrumofAustralian reptilesbut may prey selectively on some species or species groups In acomparison of actual abundance and frequency of prey in catdietary samples at a site in inland Queensland Kutt (2012)concluded that cats preyed selectively on reptile species in thesize range 10ndash50 g and less so in the size ranges 50ndash100 g and100ndash3500 g and selected against reptile specieslt10 gHoweversuch a size preference is challenging to relate to impacts onindividual species because many reptile species exhibit markedsize changes over their lifetime At a site in arid South AustraliaRead and Bowen (2001) found that cats ate fewer individualsof the reptile species (relative to their actual abundance)associated with stony plains than species associated with sanddunes and concluded that this was because at the local scalecats were more abundant in the latter habitat They also notedsome differences in cat predation rates between similarlysized co-occurring reptiles and considered that this waspossibly due to different defence responses with reptilespecies that responded vigorously to potential attack (such asthe geckoUnderwoodisaurusmilii and some large elapid snakes)experiencing lower rates of predation

Given cat hunting behaviour (and geographic variation intheir density) reptile groups likely to be most affected by catpredation are those that (1) are relatively long-lived and havelow rates of reproduction (because these may be most affectedby any factor causing increase in mortality rates) (2) have highpredictability in activity such as those with permanent burrowsor latrine sites (because the ambush strategy typically employedby cats will be most effective with such prey types Moore et al(2018)) (3) occur in habitats with relatively open groundvegetation andor in sites subject to frequent and extensivefire (because cats may occur more commonly in such areasand hunt most effectively in them Leahy et al (2015)McGregor et al (2015)) (4) are colonial or semi-colonial(because cats may develop effective search images for suchspecies and target them selectively) (5) are predominantlyterrestrial rather than arboreal or fossorial (although cats canhunt in trees and can dig up prey Saunders (1991)) (6) do notoccur in rugged rocky areas (because cat density and huntingefficiencymay be lowest in such habitats Hohnen et al (2016))and (7) occur mainly in arid or semiarid areas Several genera oflarge Australian skinks (BellatoriasCyclodomorphus EgerniaEulamprus Liopholis Nangura Tiliqua) and agamids (egPogona) exhibit many of these characteristics (Chapple 2003Moore et al 2018) and therefore can be expected to show themost pronounced impacts from cat predation Impacts may alsobe severe for some reptile species that occur on islands wherebreeding seabirds occur in part of the year allowing for high catdensities but where few other prey items are available at othertimes of the year

When averaged across Australia the rate of predation by catson reptiles may indicate (albeit with very low confidence) that a

Reptiles killed by cats in Australia Wildlife Research M

small proportion of the national reptile population is killed bycats each year however cases of very high (and selective)predation pressure are evident in some reported instances oflarge numbers of individual reptiles (oftenmostly of one species)in stomachs of single cats (Woinarski et al in press) Such highpredation rates may well lead to local depletion of populationsof some cat-targeted reptile species There are few relevantstudies that have assessed rates of mortality and their causesfor individual reptile species in Australia Sweet (2007)radio-tracked 50 individuals of Varanus tristis and V scalarisin Kakadu National Park northern Australia over a 10-monthperiod and recorded predation by cats for six of theseindividuals by far the largest source of mortality for thosemarked individuals A radio-tracking study of two largeelapid snakes in south-eastern Australia also found that catswere a major source of mortality (Whitaker and Shine 2000)and a recent study of the threatened great desert skink alsoconcluded that mortality due to feral cats was higher than thatfromanyother predator (Moore et al 2018) In a less quantitativestudy Read and Bedford (1991) considered threats to the highlylocalised snake Austrelaps labialis recorded its occurrencein samples from pet cats and consequently suggested lsquocatpredation rates on threatened pygmy copperheads may besignificant due to the large domestic and feral cat populationin the Mt Lofty Rangesrsquo (p 3) While such studies suggest that arelatively high proportion of individuals may be killed by catsfew studies have demonstrated population-level impacts partlybecause such evidence may require long-term research andintensive monitoring

Introduced predators may have direct detrimental impactson some reptile species and they may also have more diffusecommunity-level impacts A small number of Australianstudies have considered reptile assemblages in areas wherecontrasting management has led to marked differences in theabundance of foxes (Olsson et al 2005 Sutherland et al 2011)cats (Stokeld et al 2016) or both foxes and cats (Moseby et al2009 Read and Scoleri 2015) These studies indicate that manycomponents of these reptile assemblages change markedly dueto the impacts of introduced predators most likely throughtheir suppression of previously apex reptilian predators(Jessop et al 2016) Given that the rate of predation by cats ishigher than that by foxes (the present studyCatling (1988)Readand Bowen (2001)) ndash cats occur over much more of Australiathan do foxes and may often also be at higher abundance thanfoxes (Read andBowen 2001) ndash it is plausible that feral cats havehad major impacts on reptile communities across much ofAustralia However these impacts may be complex andhighly interactive as predation by cats may also have resultedin marked decreases in some native bird mammal and reptilespecies that also prey on reptiles therefore the net impact of catson individual reptile species and reptile assemblagesmaybeverydifficult to assess

The results reported here for the extent of predation by cats onAustralian reptiles can be compared with a recent study of theextent of predation by cats on Australian birds (Woinarski et al2017a) and also of the extent of predation on reptiles by cats inother continents Although mammals are typically the maincomponent of cat diet in most areas of Australia as elsewherein the world (Doherty et al 2015 2017) feral cats in largely

natural environments in Australia include a high and broadlysimilar proportion of birds and reptiles in their diet (overallfrequency of 316 and 256 respectively Woinarski et al(2017a)) Unlike for reptiles cat predation on Australian birds ishighest on islands especially smaller islands This is largelybecause cats on many Australian islands prey heavily ondense populations of breeding seabirds and may also bebecause many islands do not support mammalian prey Aswith reptiles more birds are killed by cats in hot and dryregions (at least in good rainfall years) although this patternis notably more pronounced for reptiles than for birdsNationally the total number of reptiles killed by all cats inAustralia is substantially higher than the number of birdskilled by cats (649million versus 377million)

There are no comparable robust assessments of the extent ofcat predation on reptiles for other continents In a recent reviewof the impacts of cats on wildlife in the contiguous USA basedon analysis of predation rates reported in a series of collatedstudies Loss et al (2013) located only one such study of un-owned cats that reported on reptile predation with that percapita rate (59 reptile individuals catndash1 yearndash1 Parmalee(1953)) appreciably lower than that reported here (225reptile individual catndash1 yearndash1) However estimates of thenumbers of feral (or lsquofree-roamingrsquo) cats are far higher forthe US (30ndash80million) than for Australia (21ndash63millionLegge et al (2017)) so the overall take of reptiles by catsfor the US (median 478million with a range between 258 and822 million Loss et al (2013)) is comparable to that reportedhere for Australia In their collation Loss et al (2013) alsonoted only one comparable study from Europe which reporteda rate of predation by unowned cats of 415 reptile individualscatndash1 yearndash1 Biroacute et al (2005)) Although this is a very sparsebase for comparison it suggests that the per capita rate ofpredation on reptiles by feral cats in Australia is likely to besubstantially higher than in North America and EuropeThis possibly reflects the strong association between highfrequency of reptiles in cat diets (and high densities ofreptiles) and hot and dry climate zones (Fig 2 Dohertyet al (2015)) given that most of North America and Europeis cooler and wetter than Australia

Our results suggest that cat predation may be a majorsource of mortality for Australian reptiles Howevermuch of the interpretation of this result is constrained byshortcomings in evidence our study did not seek to assesswhether predation by cats is leading to chronic ongoingdepletion in the lsquostanding croprsquo of Australian reptiles Thereare some priority areas of research that could most effectivelyaddress those shortcomings One priority is more autecologicalresearch (including assessments of demographic factors suchas the rate of predation and other mortality factors)particularly for some reptile genera with traits that renderthem likely to be susceptible to cat predation Such anapproach would allow for an assessment of the extent towhich mortality rates due to cat predation affect populationviability and size Another priority is targeted assessmentsof responses of reptile species at sites with contrastingmanagement of feral cats (such as predator-proof exclosuresor broad-scale baiting) Our study is based on collations ofcat dietary studies spaced widely across Australia but we

N Wildlife Research J C Z Woinarski

recognise that some environments (notably rainforests) andregions were relatively under-sampled and additional studiesin such sites would increase the representativeness of ouranalysis Another priority for research is to contextualise thethreat posed by cats relative to mortality due to other threatfactors and to better understand the interactions between catpredation and those factors A final priority is to substantiallyincrease the extent and coverage of population monitoringin Australian reptile species to provide more information onreptile population trends and to provide timely warning ofdeclines that may have conservation significance (Woinarski2018)

Cat predation may also subvert the assumed conservationsecurity provided to native reptiles by the conservation reservesystem given that feral cats occur in similar density within andoutsideAustraliarsquos reserve system (Legge et al 2017) Thereforeconservation of reptiles likely to be susceptible at populationscale to predation by cats will require targeted and effectivecontrol of cats rather than simply inclusion of those susceptiblespecies within the reserve system

The loss of ~18million native reptiles per day due topredation by cats provides further evidence of the potentialconservation impact of this introduced predator on Australianbiodiversity and underscores the value of efforts now beingmade to manage feral cat populations (eg through local-scaleexclosures enhanced island biosecurity broad-scale predatorcontrol programs) and the predation pressure they exert (egmanagement of fire and grazing pressure) especially targetingconservation management for species whose populationviability is most vulnerable to cat predation (Commonwealthof Australia 2015 Department of the Environment 2015)

Conflicts of interest

The authors declare no conflicts of interest

Supplementary material

Supplementary Table S1 provides a list of all Australianterrestrial reptile species showing sources of records ofpredation by cats for each species

Acknowledgements

The data collation analysis and preparation of this paper was supported bythe Australian Governmentrsquos National Environmental Science Program(Threatened Species Recovery Hub) We thank the Museum and ArtGallery of the Northern Territory (and curator Gavin Dally) Museum ofVictoria (LauraCook)TasmanianMuseumandArtGallery (BelindaBauer)Western Australian Museum (Rebecca Bray) Australian National WildlifeCollection (CSIRO Leo Joseph) Queensland Museum (Heather JanetzkiAndrew Amey) South Australian Museum (David Stemmer PhilippaHorton) and Australian Museum (Cameron Slatyer Mark Eldridge) forrecords of reptiles in their collection reported as cat-killed We thank theAustralian Research Council for grant funding (project DP 140104621) toCRD We thank Hal Cogger for information and advice and KatherineMoseby and an anonymous referee for helpful comments on an earlier draftWe thank Flavie Delanzy Taaryn Thomson and Mat Vanderklift for accessto some unpublished information on reptiles from cat samples This paperrests on data arising from the inglorious labours of many people who havesearched for and through cat faeces and the internal organs of dead cats ndash that

effort is much appreciated and we hope this collation contributes towardsa demonstration of the value of such dedicated effort

References

Abbott I (2008) The spread of the cat Felis catus in Australia re-examination of the current conceptual model with additionalinformation Conservation Science Western Australia 7 1ndash17

Abbott I Peacock D and Short J (2014) The new guard the arrival andimpacts of cats and foxes In lsquoCarnivores of Australia Past Present andFuturersquo (Eds A S Glen and C R Dickman) pp 69ndash104 (CSIROPublishing Melbourne)

Algar D and Friend J A (1995) Feral pests program Project 11Methodsof broadscale control of feral cats and fox control at a numbat re-introduction site Year 2 Department of Conservation and LandManagement Perth

Andrew P Cogger H Driscoll D Flakus S Harlow P Maple DMisso M Pink C Retallick K Rose K Tiernan B West J andWoinarski J C Z (2018) Somewhat saved a captive breeding programfor two endemic Christmas Island lizard species now extinct in the wildOryx 52 171ndash174 doi101017S0030605316001071

Animal Medicines Australia (2016) Pet ownership in Australia Availableat httpanimalmedicinesaustraliaorgauwp-contentuploads201611AMA_Pet-Ownership-in-Australia-2016-Report_smlpdf [verifiedApril 2018]

Australian Bureau of Meteorology (2016a) Average annual and monthlymaximum minimum and mean temperature httpwwwbomgovaujspnccclimate_averagestemperatureindexjsp [Verified April 2018]

Australian Bureau of Meteorology (2016b) Average annual seasonaland monthly rainfall httpwwwbomgovaujspnccclimate_averagesrainfallindexjsp [verified April 2018]

Barratt D G (1997) Predation by house cats Felis catus (L) in CanberraAustralia I Prey composition and preference Wildlife Research 24263ndash277 doi101071WR96020

Barratt D G (1998) Predation by house cats Felis catus (L) in CanberraAustralia II Factors affecting the amount of prey caught and estimates ofthe impact on wildlife Wildlife Research 25 475ndash487 doi101071WR97026

Bayly C P (1976) Observations on the food of the feral cat (Felis catus) inan arid environment South Australian Naturalist 51 22ndash24

BaylyCP (1978)Acomparisonof thediets of the red foxand the feral cat inan arid environment South Australian Naturalist 53 20ndash28

Beh J C L (1995) Thewinter ecology of the feral catFelis catus (Linnaeus1758) at Wedge Island Tasmania BSc (Hons) thesis University ofTasmania Hobart

Biroacute Z Lanszki J Szemethy L HeltaiM andRandi E (2005) Feedinghabits of feral domestic cats (Felis catus) wild cats (Felis sylvestris) andtheir hybrids trophic niche overlap among cat groups in HungaryJournal of Zoology 266 187ndash196 doi101017S0952836905006771

Blancher P (2013) Estimated number of birds killed by house cats (Feliscatus) in Canada Avian Conservation amp Ecology 8 3 doi105751ACE-00557-080203

Boumlhm M Collen B Baillie J E M Bowles P Chanson J Cox NHammerson G Hoffmann M Livingstone S R Ram M RhodinA G J Stuart S N Van Dijk P P Young B E Afuang L EAghasyan A Garcia A Aguilar C Ajtic R Akarsu F AlencarL R V Allison A Ananjeva N Anderson S Andren C Ariano-SanchezD Arredondo J C AuliyaMAustin C C Avci A BakerP J Barreto-Lima A F Barrio-Amoros C Basu D Bates M FBatistella A Bauer A Bennett D Bohme W Broadley D BrownR Burgess J Captain A Carreira S Castaneda M R Castro FCatenazzi A Cedeno-Vazquez J R Chapple D G Cheylan MCisneros-Heredia D F Cogalniceanu D Cogger H Corti C CostaG C Couper P J Courtney T Crnobrnja-Isailovic J Crochet P-ACrother B Cruz F Daltry J C Daniels R J R Das I de Silva A

Reptiles killed by cats in Australia Wildlife Research O

DiesmosACDirksenLDoanTMDoddCKDoodySDorcasM E Duarte de Barros Filho J Egan V T ElMouden E H EmbertD Espinoza R E Fallabrino A Feng X Feng Z-J Fitzgerald LFlores-Villela O Franca F G R Frost D Gadsden H Gamble TGanesh S R Garcia M A Garcia-Perez J E Gatus J Gaulke MGeniez P Georges A Gerlach J Goldberg S Gonzalez J-C TGower D J Grant T Greenbaum E Grieco C Guo P HamiltonA M Hare K Hedges S B Heideman N Hilton-Taylor CHitchmough R Hollingsworth B Hutchinson M F Ineich IIverson J B Jaksic F M Jenkins R Joger U Jose R KaskaY Kaya U Keogh S Kohler G Kuchling G Kumlutas Y KwetA La Marca E Lamar W Lane A Lardner B Latta C Latta GLau M Lavin P Lawson D LeBreton M Lehr E Limpus D JLipczynski N LoboA S Lopez-LunaMA Luiselli L LukoschekV Lundberg M Lymberakis P Macey R Magnusson W EMahler L Malhotra A Mariaux J Maritz B Marques O A VMarquez R Martins M Masterson G Mateo J A Mathew RMathews NMayer GMcCranie J RMeasey JMendoza-QuijanoFMenegonMMetrailler SMilton D AMontgomery CMoratoS AAMott TMunoz-AlonsoAMurphy J Nguyen TQ NilsonG Nogueira C Nunez H Orlov N Ota H Ottenwalder JPapenfuss T J Pasachnik S Passos P Pauwels O S G Perez-BuitragoN Perez-MelladoV Pianka E R Pleguezuelos J PollockC Ponce-Campos P Powell R Pupin F Quintero Diaz G ERadder R Ramer J Rasmussen A R Raxworthy C ReynoldsR Richman N Rico E L Riservato E Rivas G da Rocha P L BRodel M-O Rodriguez Schettino L Roosenburg W M Ross J PSadek R Sanders K Santos-Barrera G Schleich H H SchmidtB R Schmitz A Sharifi M Shea G Shi H-T Shine R SindacoR Slimani T Somaweera R Spawls S Stafford P Stuebing RSweet S S Sy E Temple H J Tognelli M F Tolley K TolsonP J TuniyevB Tuniyev SUzumaeN vanBuurtGVanSluysMVelasco A Vences M Vesely M Vinke S Vinke T Vogel GVogrin M Vogt R C Wearn O R Werner Y L Whiting M JWiewandt TWilkinson JWilsonBWren SZaminT andZugG(2013) The conservation status of the worldrsquos reptiles BiologicalConservation 157 372ndash385 doi101016jbiocon201207015

BoumlhmMWilliamsR Bramhall HRMcMillanKMDavidsonADGarcia A Bland L M Bielby J and Collen B (2016) Correlates ofextinction risk in squamate reptiles the relative importance of biologygeography threat and range sizeGlobal Ecology and Biogeography 25391ndash405 doi101111geb12419

Braysher M (1993) The need for a critical review of the impact of pestanimals on Australiarsquos herpetofauna In lsquoHerpetology in Australiaa Diverse Disciplinersquo (Eds D Lunney and D Ayers) p 36 (RoyalZoological Society of New South Wales Sydney)

Brooker M G (1977) Some notes on the mammalian fauna of the westernNullarbor Plain Western Australia Western Australian Naturalist(Perth) 14 2ndash15

Buckmaster A J (2011) Ecology of the feral cat (Felis catus) in the tallforests of Far East Gippsland PhD thesis University of SydneySydney

Burnett S E (2001) Ecology and conservation status of the northernspot-tailed quoll Dasyurus maculatus with reference to the future ofAustraliarsquos marsupial carnivores PhD Thesis James Cook UniversityTownsville

Burnham K P and Anderson D R (2003) lsquoModel Selection andMultimodel Inference a Practical Information-Theoretic Approachrsquo(Springer New York)

Burrows N D Algar D Robinson A D Sinagra J Ward B andLiddelow G L (2003) Controlling introduced predators in theGibson Desert of Western Australia Journal of Arid Environments55 691ndash713 doi101016S0140-1963(02)00317-8

Cahill K (2005) Morphometrics diet and aspects of disease inTasmanian feral and stray cats BSc (Hons) thesis University ofTasmania Hobart

Catling P C (1988) Similarities and contrasts in the diets of foxesVulpes vulpes and cats Felis catus relative to fluctuating preypopulations and drought Wildlife Research 15 307ndash317 doi101071WR9880307

Chapman A D (2009) lsquoNumbers of Living Species in Australia and theWorldrsquo (Australian Biological Resources Study Canberra)

Chapple D G (2003) Ecology life-history and behavior in theAustralian scincid genus Egernia with comments on the evolution ofcomplex sociality in lizards Herpetological Monograph 17 145ndash180doi1016550733-1347(2003)017[0145ELABIT]20CO2

Cogger H G (2014) lsquoReptiles and Amphibians of Australiarsquo Seventh edn(CSIRO Publishing Melbourne)

CoggerHFordH JohnsonCHolman J andButlerD (2003) lsquoImpactsof Land Clearing on Australian Wildlife in Queenslandrsquo (World WideFund for Nature Australia Brisbane)

Cogger H Dickman C Ford H Johnson C and Taylor M F J (2017)lsquoAustralian Animals Lost to Bulldozers in Queensland 2013ndash15 WWF-Australiarsquo (WWF-Australia Sydney)

Coman B J (1972) Helminth parasites of the dingo and feral dog inVictoria with some notes on the diet of the host Australian VeterinaryJournal 48 456ndash461 doi101111j1751-08131972tb02281x

Coman B J and Brunner H (1972) Food habits of the feral house cat inVictoriaTheJournal ofWildlifeManagement36 848ndash853 doi1023073799439

Commonwealth of Australia (2015) lsquoThreatened Species Strategyrsquo(Commonwealth of Australia Canberra)

Corbett L K (1995) lsquoTheDingo inAustralia andAsiarsquo (University of NewSouth Wales Press Sydney)

Corbett L Corome F and Richards G (2003) Fauna survey of minelease applications amp National Park reference areas Christmas IslandAugust 2002 EWL Sciences Pty Ltd for Phosphate Resources LimitedDarwin

Crawford H (2010) A comparison of the red fox (Vulpes vulpes) and feralcat (Felis catus) diets in the south west region of Western Australia PhD thesis Murdoch University Perth

Davies W and Prentice R (1980) The feral cat in Australia Wildlife inAustralia 17 20ndash26

DellerMMillsHRHamiltonN andAlgarD (2015)Diet of feral catsFelis catus on Dirk Hartog Island Journal of the Royal Society ofWestern Australia 98 37ndash43

Denny E A (2005) Ecology of free-living cats exploiting waste disposalsites dietmorphometrics population dynamics and population geneticsPhD thesis University of Sydney Sydney

Department of the Environment (2015) Threat abatement plan for predationby feral cats (Commonwealth of Australia Canberra)

Dickman CRWardleGM Foulkes JN and de PreuN (2014)Desertcomplex environments In lsquoBiodiversity and Environmental Changersquo(EdsD Lindenmayer E BurnsN Thurgate andA Lowe) pp 379ndash438(CSIRO Publishing Melbourne)

Doherty T S (2015) Dietary overlap between sympatric dingoes and feralcats at a semiarid rangeland site in Western Australia AustralianMammalogy 37 219ndash224 doi101071AM14038

Doherty T S Davis R A Etten E J B Algar D Collier N DickmanC R Edwards G Masters P Palmer R and Robinson S (2015)A continental-scale analysis of feral cat diet in Australia Journal ofBiogeography 42 964ndash975 doi101111jbi12469

Doherty T S GlenA S NimmoDG Ritchie E G andDickman C R(2016) Invasive predators and global biodiversity loss Proceedings ofthe National Academy of Sciences of the United States of America 11311261ndash11265 doi101073pnas1602480113

P Wildlife Research J C Z Woinarski

DohertyTSDickmanCR JohnsonCNLeggeSMRitchieEG andWoinarski J C Z (2017) Impacts and management of feral catsFelis catus in Australia Mammal Review 47 83ndash97 doi101111mam12080

Ehmann H F W and Cogger H G (1985) Australiarsquos endangeredherpetofauna a review of criteria and policies In lsquoThe Biology ofAustralasian Frogs and Reptilesrsquo (Eds G C Grigg R Shine andH F W Ehmann) pp 435ndash447 (Surrey Beatty and Sons with RoyalZoological Society of New South Wales Sydney)

Evans M C (2016) Deforestation in Australia drivers trends and policyresponses Pacific Conservation Biology 22 130ndash150 doi101071PC15052

Fielder D P Limpus D J and Limpus C J (2015) Reproduction andpopulation ecology of the vulnerable western sawshelled turtleMyuchelys bellii in the MurrayndashDarling Basin Australia AustralianJournal of Zoology 62 463ndash476 doi101071ZO14070

Fordham D A Georges A Corey B and Brook B W (2006) Feral pigpredation threatens the indigenous harvest and local persistence of snake-necked turtles in northern Australia Biological Conservation 133379ndash388 doi101016jbiocon200607001

Fordham D A Georges A and Brook B W (2008) Indigenous harvestexotic pig predation and local persistence of a long-lived vertebratemanaging a tropical freshwater turtle for sustainability and conservationJournal of Applied Ecology 45 52ndash62 doi101111j1365-2664200701414x

Foulkes J (2002) The ecology and management of the common brushtailpossum (Trichosurus vulpecula) in central Australia PhD thesisUniversity of Canberra Canberra

FreemanA Thomson S andCann J (2014)Elseya lavarackorum (Whiteand Archer 1994) ndash Gulf Snapping Turtle Gulf Snapper RiversleighSnapping Turtle Lavarackrsquos Turtle In lsquoConservation Biology ofFrshwater Turtles and Tortoises a Compilation Project of the IUCNTortoise and Freshwater Turtle Specialist Grouprsquo (Eds A G J RhodinP C H Pritchard P P van Dijk R A Saumure K A BuhlmannJ B Iverson and R A Mittermeier) pp 0821ndash08210 doi103854crm5082lavarackorumv12014

George W G (1978) Domestic cats as density independent hunters andlsquosurplusrsquo killers Carnivore Genetics Newsletter 3 282ndash287

Glen A S Pennay M Dickman C R Wintle B A and Firestone K B(2011) Diets of sympatric native and introduced carnivores in theBarrington Tops eastern Australia Austral Ecology 36 290ndash296doi101111j1442-9993201002149x

Greenville A C Wardle G M Nguyen V and Dickman C R (2016)Spatial and temporal synchrony in reptile population dynamics invariable environments Oecologia 182 475ndash485 doi101007s00442-016-3672-8

HansenMCDeFries R S Townshend J RG CarrollMDimiceli Cand Sohlberg R A (2003) Global percent tree cover at a spatialresolution of 500m first results of the MODIS vegetation continuousfields algorithm Earth Interactions 7 art10 doi1011751087-3562(2003)007lt0001GPTCAAgt20CO2

Hart S (1994)Thediet of foxes (Vulpes vulpes) and feral cats (Felis catus) inthe Flinders RangesNational Park SouthAustralia BSc (Hons) thesisUniversity of Adelaide Adelaide

HaydeKA (1992) Ecology of the feral catFelis catus onGreatDog IslandBSc (Hons) thesis University of Tasmania Hobart

Hohnen R Tuft KMcGregor HW Legge S Radford I J and JohnsonC N (2016) Occupancy of the invasive feral cat varies with habitatcomplexity PLoS One 11 e0152520 doi101371journalpone0152520

Holden C andMutze G (2002) Impact of rabbit haemorrhagic disease onintroduced predators in the Flinders Ranges South Australia WildlifeResearch 29 615ndash626 doi101071WR00101

HubbsE L (1951) Foodhabits of feral house cats in theSacramentoValleyCalifornia Fish and Game 37 177ndash189

Hutchings S (2003) The diet of feral house cats (Felis catus) at a regionalrubbish tip Victoria Wildlife Research 30 103ndash110 doi101071WR99067

JacksonWB (1951) Foodhabits ofBaltimoreMaryland cats in relation torat populations Journal of Mammalogy 32 458ndash461 doi1023071375794

Jarvis A Reuter H I Nelson A and Guevara E (2008) Hole-filledSRTM for the globe Version 4 available from the CGIAR-CSI SRTM90m Database httpwwwcgiar-csiorgdatasrtm-90m-digital-elevation-database-v4-1

Jessop T S Gillespie G and Letnic M (2016) Examining multi-scale effects of the invasive fox on a large varanid (Varanusvarius White 1790) mesopredator In lsquoInterdisciplinary WorldConference on Monitor Lizardsrsquo (Ed M Cota) pp 221ndash236(Institute for Research and Development Suan Sunandha RajabhatUniversity Bangkok)

Jessup D A (2004) The welfare of feral cats and wildlife Journal of theAmericanVeterinaryMedicalAssociation225 1377ndash1383 doi102460javma20042251377

Johnston M Gigliotti F OrsquoDonoghue M Holdsworth M Robinson SHerrodA andEklomK (2012) Field assessment of theCuriosityregbaitfor management of feral cats in the semi-arid zone (Flinders RangesNational Park) Technical Report Series no 234 Arthur Rylah Institutefor Environmental Research Melbourne

Johnston M OrsquoDonoghue M Holdsworth M Robinson S Herrod AEklomKGigliotti F Bould L andLittleN (2013) Field assessmentof the Curiosityreg bait for managing feral cats in the Pilbara TechnicalReport Series no 245 Arthur Rylah Institute for EnvironmentalResearch Melbourne

Jones E (1977) Ecology of the feral cat Felis catus (L) (CarnivoraFelidae) on Macquarie Island Australian Wildlife Research 4 249ndash262doi101071WR9770249

Jones E and Coman B J (1981) Ecology of the feral cat Felis catus (L)in south-eastern Australia I Diet Australian Wildlife Research 8537ndash547 doi101071WR9810537

Kays R W and DeWan A A (2004) Ecological impact of insideoutsidehouse cats around a suburban nature preserve Animal Conservation 7273ndash283 doi101017S1367943004001489

Kirkwood RDann P andBelvedereM (2005)A comparison of the dietsof feral cats Felis catus and red foxes Vulpes vulpes on Phillip IslandVictoria Australian Mammalogy 27 89ndash93 doi101071AM05089

Kutt A S (2011) The diet of the feral cat (Felis catus) in north-easternAustralia Acta Theriologica 56 157ndash169 doi101007s13364-010-0016-7

Kutt A S (2012) Feral cat (Felis catus) prey size and selectivity in north-eastern Australia implications for mammal conservation Journal ofZoology 287 292ndash300 doi101111j1469-7998201200915x

Lapidge S J and Henshall S (2001) Diet of foxes and cats with evidenceof predation on yellow-footed rock-wallabies (Petrogale xanthopusceleris) by foxes in southwestern Queensland Australian Mammalogy23 47ndash51 doi101071AM01047

Lazenby B T (2012) Do feral cats affect small mammals A case studyfrom the forests of southern Tasmania PhD thesis University ofSydney Sydney

Leahy L Legge S M Tuft K McGregor H Barmuta L Jones M Eand Johnson C N (2015) Amplified predation after fire suppressesrodent populations in Australiarsquos tropical savannas Wildlife Research42 705ndash716 doi101071WR15011

Legge S Murphy B P McGregor H Woinarski J C Z Augusteyn JBallard G Baseler M Buckmaster T Dickman C R Doherty TEdwardsG Eyre T Fancourt B FergusonD ForsythDM GearyW L Gentle M Gillespie G Greenwood L Hohnen R Hume SJohnson C N Maxwell N McDonald P Morris K Moseby KNewsome T Nimmo D Paltridge R Ramsey D Read J Rendall

Reptiles killed by cats in Australia Wildlife Research Q

A Rich M Ritchie E Rowland J Short J Stokeld D SutherlandD R Wayne A F Woodford L and Zewe F (2017) Enumeratinga continental-scale threat how many feral cats are in AustraliaBiological Conservation 206 293ndash303 doi101016jbiocon201611032

Limpus C andReimerD (1994) The loggerhead turtleCaretta caretta inQueensland a population in decline In lsquoProceedings of the AustralianMarine Turtle Conservation Workshoprsquo (Ed R James) pp 39ndash47(Australian Nature Conservation Agency Canberra)

Loss S R Will T and Marra P P (2013) The impact of free-rangingdomestic cats onwildlife of theUnited StatesNatureCommunications 41396 doi101038ncomms2380

Loyd K A T Hernandez S M Carroll J P Abernathy K J andMarshall G J (2013) Quantifying free-roaming domestic cat predationusing animal-borne video cameras Biological Conservation 160183ndash189 doi101016jbiocon201301008

Maclean M (2007) Impact of domestic cat predation on bird and smallmammal populations PhD thesis University of Exeter Exeter UK

MahonP S (1999) Predationby feral cats and red foxes and thedynamics ofsmall mammal populations in arid Australia PhD thesis University ofSydney Sydney

Martin G R Twigg L E and Robinson D J (1996) Comparison of thediet of feral cats from rural and pastoral Western Australia WildlifeResearch 23 475ndash484 doi101071WR9960475

McGregor H Legge S Jones M E and Johnson C N (2015) Feral catsare better killers in open habitats revealed by animal-borne video PLoSOne 10 e0133915 doi101371journalpone0133915

McGregor H W Cliff H B and Kanowski J (2016) Habitat preferencefor fire scars by feral cats in Cape York Peninsula Australian WildlifeResearch 43 623ndash633 doi101071WR16058

Meiri S (2016) Small rare and trendy traits and biogeography of lizardsdescribed in the 21st century Journal of Zoology 299 251ndash261doi101111jzo12356

Meiri S and Chapple D G (2016) Biases in the current knowledge ofthreat status in lizards and bridging the lsquoassessment gaprsquo BiologicalConservation 204 6ndash15 doi101016jbiocon201603009

Micheli-Campbell M A Baumgartl T Booth D T Campbell H AConnell M and Franklin C E (2013) Selectivity and repeated use ofnesting sites in a freshwater turtle Herpetologica 69 383ndash396doi101655HERPETOLOGICA-D-12-00057

Mifsud G and Woolley P A (2012) Predation of the Julia Creek dunnart(Sminthopsis douglasi) and other native fauna by cats and foxes onMitchell grass downs in Queensland Australian Mammalogy 34188ndash195 doi101071AM11035

Molsher R Newsome A and Dickman C (1999) Feeding ecology andpopulation dynamics of the feral cat (Felis catus) in relation to theavailability of prey in central-eastern New South Wales WildlifeResearch 26 593ndash607 doi101071WR98058

MolsherRLGiffordE J andMcIlroy JC (2000)Temporal spatial andindividual variation in the diet of red foxes (Vulpes vulpes) in centralNewSouth Wales Wildlife Research 27 593ndash601 doi101071WR99015

Molsher R L Newsome A E Newsome T M and Dickman C R(2017) Mesopredator management effects of red fox control on theabundance diet and use of space by feral cats PLoS One 12 e0168460doi101371journalpone0168460

Moore D Kearney M R Paltridge R McAlpin S and Stow A (2018)Feeling the pressure at home Predator activity at the burrow entrance ofan endangered arid-zone skink Austral Ecology 43 102ndash109doi101111aec12547

Morton S R and James C D (1988) The diversity and abundance oflizards in arid Australia a new hypothesis American Naturalist 132237ndash256 doi101086284847

Moseby K E Hill B M and Read J L (2009) Arid recovery ndash acomparison of reptile and smallmammal populations inside and outside a

large rabbit cat and fox-proof exclosure in arid South AustraliaAustral Ecology 34 156ndash169 doi101111j1442-9993200801916x

Muir B G (1982) Cats in Western Australian national parks AustralianRanger Bulletin 2 8

Nielsen T P and Bull C M (2016) Impact of foxes digging for thepygmy bluetongue lizard (Tiliqua adelaidensis) Transactions of theRoyal Society of South Australia 140 228ndash233 doi1010800372142620161196473

OrsquoConnell G J (2010) The diet of feral cats (Felis catus) in the FitzgeraldRiver National Park south-western Australia BSc (Hons) thesisUniversity of Western Australia Perth

Oliver PM AdamsM LeeM S Y HutchinsonM N andDoughty P(2009) Cryptic diversity in vertebrates molecular data doubleestimates of species diversity in a radiation of Australian lizards(Diplodactylus Gekkota) Proceedings of the Royal Society ofLondon Series B Biological Sciences 276 2001ndash2007 doi101098rspb20081881

Oliver PM Laver R J DeMelloMartins F Pratt R C Hunjan S andMoritz C (2017) A novel hotspot of vertebrate endemism and anevolutionary refugium in tropical Australia Diversity amp Distributions23 53ndash66 doi101111ddi12506

Olsson M Wapstra E Swan G Snaith E Clarke R and Madsen Y(2005) Effects of long-term fox baiting on species composition andabundance in an Australian lizard community Austral Ecology 30899ndash905 doi101111j1442-9993200501534x

Palmer R A (1995) Diet of the red fox (Vulpes vulpes) in south-westernQueensland The Rangeland Journal 17 99ndash108 doi101071RJ9950099

Paltridge R (2002) The diets of cats foxes and dingoes in relation to preyavailability in the Tanami Desert Northern TerritoryWildlife Research29 389ndash403 doi101071WR00010

Paltridge R Gibson D and Edwards G (1997) Diet of the feral cat(Felis catus) in central Australia Wildlife Research 24 67ndash76doi101071WR96023

Paltridge R Johnston A Fitzpatrick S and Goodman C (2016)Reversing the decline of mammals in northern Australia response ofnative mammals to cat management on the Pellew Islands 2011ndash2015Desert Wildlife Surveys Alice Springs

Parmalee P W (1953) Food habits of the feral house cat in east-centralTexas The Journal of Wildlife Management 17 375ndash376 doi1023073797127

Paton D (1990) Domestic cats and wildlife results from initialquestionnaire Bird Observer 696 34ndash35

Paton D C (1991) Loss of wildlife to domestic cats In lsquoThe Impact of Catson Native Wildlifersquo (Ed C Potter) pp 64ndash69 (Australian NationalParks amp Wildlife Service Canberra)

Paton D C (1993) Impacts of domestic and feral cats on wildlife In lsquoCatManagement Workshop Proceedings ndash 1993rsquo (Eds G Siepen andC Owens) pp 9ndash15 (Queensland Department of Environment andHeritage Brisbane)

Pavey C R Eldridge S R andHeywoodM (2008) Population dynamicsand prey selection of native and introduced predators during a rodentoutbreak in arid Australia Journal of Mammalogy 89 674ndash683doi10164407-MAMM-A-168R1

Pedler R D and Lynch C E (2016) An unprecedented irruption andbreeding of Flock Bronzewings Phaps histrionica in central SouthAustralia Australian Field Ornithology 33 1ndash13 doi1020938afo33001013

Pianka E R (1969) Habitat specificity speciation and species densityin Australian desert lizards Ecology 50 498ndash502 doi1023071933908

Pianka E R (1981) Diversity and adaptive radiations of Australian desertlizards In lsquoEcological Biogeography of Australiarsquo (Ed A Keast)pp 1377ndash1392 (W Junk The Hague)

R Wildlife Research J C Z Woinarski

Pianka E R (1989) Desert lizard diversity additional comments andsome data American Naturalist 134 344ndash364 doi101086284985

Powney G D Grenyer R Orme C D L Owens I P F and Meiri S(2010) Hot dry and different Australian lizard richness is unlike thatof mammals amphibians and birds Global Ecology and Biogeography19 386ndash396 doi101111j1466-8238200900521x

Read J L and Bedford G (1991) The distribution and ecology ofthe Pygmy Copperhead Snake (Austrelaps labialis) Herpetofauna21 1ndash6

Read J and Bowen Z (2001) Population dynamics diet and aspects ofthe biology of feral cats and foxes in arid South Australia WildlifeResearch 28 195ndash203 doi101071WR99065

Read J L and Scoleri V (2015) Ecological implications of reptilemesopredator release in arid South Australia Journal of Herpetology49 64ndash69 doi10167013-208

Read J LKovacK-J BrookBW andFordhamDA (2012)Boomingduring a bust asynchronous population responses of arid zone lizardsto climatic variables Acta Oecologica 40 51ndash61 doi101016jactao201109006

Risbey D A Calver M C and Short J (1999) The impact of cats andfoxes on the small vertebrate fauna of Heirisson Prong WesternAustralia I Exploring potential impact using diet analysis WildlifeResearch 26 621ndash630 doi101071WR98066

Robley A Howard K Lindeman M Cameron E Jardine A andHiscock D (2016) The effectiveness of short-term fox control inprotecting a seasonally vulnerable species the Eastern Long-neckedTurtle (Chelodina longicollis) Ecological Management amp Restoration17 63ndash69 doi101111emr12199

RollU FeldmanANovosolovMAllisonA BauerAMBernardRBoumlhmMCastro-Herrera FChirioLCollenBCioliGRDaboolL Das I Doan TMGrismer L L HoogmoedM ItescuY KrausF LeBreton M Lewin A Martins M Maza E Meirte D NagyZ T Nogueira CC PauwelsO SG Pincheira-DonosoD PowneyG D Sindaco R Tallowin O J S Torres-Carvajal O Trape J-FVidan E Uetz P Wagner P Wang Y Orme C D L Grenyer Rand Meiri S (2017) The global distribution of tetrapods reveals a needfor targeted reptile conservation Nature Ecology amp Evolution 11677ndash1682 doi101038s41559-017-0332-2

Rosauer D F Blom M P K Bourke G Catalano S Donnellan SGillespie G Mulder E Oliver P M Potter S and Pratt R (2016)Phylogeography hotspots and conservation priorities an example fromthe Top End of Australia Biological Conservation 204 83ndash93doi101016jbiocon201605002

Saunders D A (1991) The effect of land clearing on the ecology ofCarnabyrsquos Cockatoo and the inland red-tailed black-cockatoo in thewheatbelt of Western Australia Acta XX Congressus InternationalisOrnithologici 1 658ndash665

Schwarz E (1995) Habitat use in a population ofmainland Tasmanian feralcats Felis catus GradDip (Hons) thesis University of TasmaniaHobart

Smith M J Cogger H Tiernan B Maple D Boland C Napier FDetto T and Smith P (2012) An oceanic island reptile communityunder threat the decline of reptiles on Christmas Island Indian OceanHerpetological Conservation and Biology 7 206ndash218

Spencer R-J (2002) Experimentally testing nest site selection fitnesstrade-offs and predation risk in turtles Ecology 83 2136ndash2144doi1018900012-9658(2002)083[2136ETNSSF]20CO2

Spencer R-J and Thompson M B (2005) Experimental analysis of theimpact of foxes on freshwater turtle populations Conservation Biology19 845ndash854 doi101111j1523-1739200500487x

Spencer E E Crowther M S and Dickman C R (2014) Diet and preyselectivity of three species of sympatric mammalian predators in central

Australia Journal of Mammalogy 95 1278ndash1288 doi10164413-MAMM-A-300

Spencer E E Newsome T M and Dickman C R (2017) Prey selectionand dietary flexibility of three species of mammalian predator duringan irruption of non-cyclic prey Royal Society Open Science 4 170317doi101098rsos170317

Stokeld D Gentles T Young S Hill B Fisher A Woinarski J andGillespie G (2016) Experimental evaluation of the role of feral catpredation in the decline of small mammals in Kakadu National Park NTDepartment of Land Resource Management Berrimah

Strong B W and Low W A (1983) Some observations of feral catsFelis catus in the southern Northern Territory Technical Report 9Conservation Commission of the Northern Territory Alice Springs

Sutherland D R Glen A S and Paul J (2011) Could controllingmammalian carnivores lead to mesopredator release of carnivorousreptiles Proceedings of the Royal Society of London Series BBiological Sciences 278 641ndash648 doi101098rspb20102103

Sweet S S (2007) Comparative spatial ecology of two small arborealmonitors in northern Australia In lsquoAdvances in Monitor Research IIIrsquo(Eds H-G Horn W Boehme and U Krebs) pp 378ndash402 (EditionChimaira Rheinbach)

Tidemann C R Yorkston H D and Russack A J (1994) The diet ofcats Felis catus on Christmas Island Indian Ocean Wildlife Research21 279ndash286 doi101071WR9940279

Triggs B Brunner H and Cullen J M (1984) The food of fox dog andcat in Croajingalong National Park south-eastern Victoria AustralianWildlife Research 11 491ndash499 doi101071WR9840491

Trueman P (1991) The impact of domestic and semi-domestic cats onthe wildlife of southern Tasmania BSc (Hons) thesis University ofTasmania Hobart

van Herk P (1980) A dietary study of the feral cat Felis catus in a ruralenvironment with emphasis on its ecology BNatRes thesis Universityof New England Armidale

Watson K (2006) Aspects of the history home range and diet of theferal cat (Felis catus) in the Perisher Range resort area of KosciuszkoNational Park New South Wales MSc thesis University of SydneySydney

Whitaker P B and Shine R (2000) Sources of mortality of large elapidsnakes in an agricultural landscape Journal ofHerpetology 34 121ndash128doi1023071565247

Whytlaw P A EdwardsW and Congdon B C (2013)Marine turtle nestdepredation by feral pigs (Sus scrofa) on the Western Cape YorkPeninsula Australia implications for management Wildlife Research30 377ndash384

Woinarski J C Z (2018) The extent and adequacy of monitoring forAustralian threatened reptile species In lsquoMonitoring Threatened Speciesand Ecological Communitiesrsquo (Eds S Legge D B LindenmayerN M Robinson B C Scheele D M Southwell and B A Wintle)pp 69ndash84 (CSIRO Publishing Melbourne)

Woinarski J C Z Burbidge AA andHarrison P L (2015) The ongoingunravelling of a continental fauna decline and extinction of Australianmammals since European settlement Proceedings of the NationalAcademy of Sciences of the United States of America 112 4531ndash4540doi101073pnas1417301112

Woinarski J C ZMurphy B P Legge SM Garnett S T LawesM JComer S Dickman C R Doherty T S Edwards G Nankivell APaton D Palmer R and Woolley L A (2017a) How many birds arekilled by cats in Australia Biological Conservation 214 76ndash87doi101016jbiocon201708006

Woinarski J C Z Woolley L A Garnett S T Legge S M MurphyB P Lawes M J Comer S Dickman C R Doherty T S EdwardsG Nankivell A Palmer R and Paton D (2017b) Compilation and

Reptiles killed by cats in Australia Wildlife Research S

traits of Australian bird species killed by cats Biological Conservation216 1ndash9 doi101016jbiocon201709017

Woinarski J C Z South S L Drummond P Johnston G R andNankivell A (In press) The diet of the feral cat (Felis catus) red fox(Vulpes vulpes) and dog (Canis familiaris) over a three-year period atWitchelina Reserve in arid South Australia Australian Mammalogydoi101071AM17033

Wysong M L (2016) Predator ecology in the arid rangelands ofWestern Australia spatial interactions and resource competition

between an apex predator the dingo Canis dingo and an introducedmesopredator the feral cat Felis catus PhD thesis University ofWestern Australia Perth

Yip S J S Rich M and Dickman C R (2015) Diet of the feral catFelis catus in central Australian grassland habitats during populationcycles of its principal preyMammal Research 60 39ndash50 doi101007s13364-014-0208-7

T Wildlife Research J C Z Woinarski

wwwpublishcsiroaujournalswr

predators are generally not well resolved for continental reptilefaunas because there is little information on predation rates oron the effects of predation rates on the population viability ofany reptile species In Australia the significance of predationby introduced species upon reptiles is also difficult to evaluatebecause the reptile fauna is incompletely catalogued In additionpopulation trends for reptile species are difficult to discernbecause there are few substantial population monitoringprograms for reptiles (Meiri 2016 Meiri and Chapple 2016Woinarski 2018)Nonetheless recent studies havedemonstratedsevere impacts of introduced predators on at least localpopulations of some Australian reptiles For example highrates of predation on egg clutches by the introduced Europeanred fox (Vulpes vulpes) and pig (Sus scrofa) are implicatedin population declines of several species some threatenedof freshwater turtles (Spencer 2002 Spencer and Thompson2005 Fordham et al 2006 2008 Micheli-Campbell et al 2013Whytlaw et al 2013 Freeman et al 2014 Fielder et al 2015Robley et al 2016) and marine turtles (Limpus and Reimer1994) Predation by the red fox is also a recognised threat to somethreatened Australian lizard species (Nielsen and Bull 2016)Furthermore predation by the red fox has been implicated incomplex but substantial changes in some Australian reptilecommunities (particularly suppression of native reptilianpredators Olsson et al 2005 Sutherland et al 2011 Readand Scoleri 2015) Introduced predators probably primarilythe wolf snake (Lycodon capucinus) are also considered tohave caused the recent collapse of the endemic reptile faunaof theAustralian external territory of Christmas Island with fourof thefive native lizard species becoming extinct or extinct in thewild over the last decade (Smith et al 2012Andrew et al 2018)

Here we assess the extent of predation by the introducedhouse cat (Felis catus) on the Australian reptile fauna Catswere introduced to Australia at the time of European settlement(1788) and have since spread across the entire continent andonto most large islands (Abbott 2008 Abbott et al 2014 Leggeet al 2017) They have caused severe detrimental impacts onthe Australian mammal fauna (Woinarski et al 2015) and area major source of mortality for Australian birds (Woinarskiet al 2017a) There has been far less consideration of theirimpacts on the Australian reptile fauna The most substantialassessmentwaswithina recent studyofcontinental-scalevariationin the diet of feral cats (Doherty et al 2015) That study reportedthat (1) reptiles formed a significant component of the diet of cats(average frequency of occurrence 24 in cat dietary samples)(2) therewas substantial geographic variation in the occurrence ofreptiles in cat diet with a higher frequency of reptiles in cat dietarysamples from hotter drier areas and in mid-latitudes and (3) 157reptile species had been recorded within the diet of feral cats inAustralia including one threatened species the recently extinctChristmas Island forest skink (Emoia nativitatis)

Using a recent assessment of geographic variation in thedensity and hence total population size of feral cats inAustralia (Legge et al 2017) information on the number ofindividual reptiles within cat dietary samples (as distinct fromsimply the percentage occurrence of reptiles in dietary samples)and a more extensive compilation of cat diet information weextend the study of Doherty et al (2015) to evaluate the annualtally of reptiles killed by cats inAustralia and the spatial variation

in this number This study complements collates informationfrom many of the studies reported in and adopts a similaranalytical approach to a recent assessment of the number andspecies of birds killed by cats in Australia (Woinarski et al2017a 2017b) Our objectives are to (1) examine environmentaland geographical variation in the number of reptiles killed byferal cats (2) derive an overall estimate of the number of reptileskilled by feral cats annually (3) attempt to contextualise thisestimate in relation to the overall number of reptiles in Australia(4) compare these assessments with the number of birds killed inAustralia by cats (Woinarski et al 2017a) (5) compile anupdated inventory of Australian reptile species known to bekilled by feral cats (6) interpret the conservation consequencesand implications of these results and (7) compare these resultswith available information fromother continentsOurmain focusis on feral cats in largely natural environments but we alsoinclude some information on predation of reptiles by pet cats andby feral cats in highly modified environments

This assessment is of some global significance because theAustralian reptile fauna comprises more than 10 of theglobal reptile complement most Australian species (gt90)are endemic (Chapman 2009) and because the conservationmanagement of reptiles has been notably neglected globallycompared with other vertebrate groups (Roll et al 2017)

Methods


To determine the numbers of feral cats in Australia and thespatial variation in cat density Legge et al (2017) collated andthen modelled 91 site-based estimates of feral cat density fromlargely natural sites widely and representatively scattered acrossAustralia They concluded that the total number of feral cats inlargely natural landscapes inAustralia was 207million (varyingbetween 14million in drought and average years to 56millionafter prolonged and extensive wet periods in inland Australia)

We collated 82 results from Australian studies (with aminimum of 10 cat scat or stomach samples per study) thatprovided a quantitative assessment of the frequency ofoccurrence of reptiles in cat stomachs or scats (Table 1) Thesestudies were widely spread across Australia (Fig 1) and includedbroad representation of Australian natural environments Intotal 32 of these studies were also included in a previousconsideration of continental variation in the diet of feral cats inAustralia (Doherty et al 2015) Where multiple studies providedestimates for the same location thesewere averaged (weighted bythe number of samples examined) Several individual studiesreported information from more than one site or from the samesite in markedly different conditions where the source data couldbe readily resolved to site level information from these separatesitesorconditionswas treatedasdistinctdatapoints inouranalyses(as per Table 1) such that the total number of study sitecombinations included in our analyses (98) exceeds the numberof included studies

Although the frequency of occurrence of reptiles in the diet offeral cats in Australia generally increases in warmer seasonsconsistent with seasonal variation in reptile activity (Paltridge2002 Yip et al 2015) it was not possible for us to account forseasonal variation in cat diet in this analysis becausemany of the

B Wildlife Research J C Z Woinarski






Sampletype

Site type Source















Sampletype

Site type Source


























2500 mm

100 mm






10 000

n o











Pet cats










Results





0

20

40

60

80

100

0 5 10 15 20 25 30


0

20

40

60

80

100

0 1000 2000 3000

Fre

quen

cy o

f rep

tiles

in c

at d

iets

(

)


(a)

(b)












Pet cats






Model DQAICc wi R2




44 003 056


46 003 056


60

10















0

1

2

3

4

5

6

0 20 40 60 80

Indi

vidu

al r

eptil

es p

er d

iet s

ampl

e



0

5

10

15

20

25

30

35

0 800 1600 2400 3200 4000

Fre

quen

cy (

)


0

3

6

9

12

0 100 200 300 400

Fre

quen

cy (

)



Wet periods only





Tab

le3

Percentag

eof

allreptile

siden

tified


yreptile

family

for

stud

iesrepo

rtingtheiden

tity

andnu

mbe

rsof

allreptile

sconsum

edby

feralcats

lsquoFreqOccrsquo

isthe

ofcatsamples

that

contained

reptileslsquoN

oreptilesrsquois

thetotalnu

mberof

reptileindividu

alsrepo

rted

incatdietary

samples

inthestud

yReptile

families

Gecko

es(C

arph

odactylidae


nidae)Pyg

op(Pyg

opod

idae)

Agam(A

gamidae)

Scinc(Scincidae)

Varan(V

aranidae)

Typ

hl(Typ

hlop

idae)

Colub

(C

olub

ridae)Boid

(Boidae)

Elap

(Elapidae)N

otethat

none

ofthelisted

stud

iesinclud

edcrocod

ilesm

arineor

freshw

ater

turtlesor

file

snakes

ascatdietaryitem

s

Location

Sou

rce

Freq

Occ

No

reptiles

Gecko

esPyg

op

Agam

Scinc

Varan

Typ

hl

Colub

Boid

Elapid

Wedge

Island

Tas

Beh

(199

5)15

800

00

00

1000

00

00

00

00

00

NingalooCapeRangeW

ADelanzyT

hompson

and

Vanderkift(unp

ubl)

400

1266

783

00

83

167

00

00

00

00

MtIsaQld

Dickm

an(unp

ubl)

462

2611

538

308

346

00

38

00

00

154

Katherine

ndashVRDN

TDickm

an(unp

ubl)

414

3339

461

30

455

00

30

00

00

30

RottnestIsland

WA

Dickm

an(unp

ubl)

219

1010

000

00

700

00

00

00

00


oppin

WA

Dickm

an(unp

ubl)

104

600

00

333

667

00

00

00

00

00

Dwelling

upW

ADickm

an(unp

ubl)

71

100

00

00

1000

00

00

00

00

00

GreatDog

Island

Tas

Hayde

(199

2)51

647

00

00

00

936

00

00

00

00

64

Flind

ersRangesSA

John

ston

etal(20

12)

292

900

00

00

1000

00

00

00

00

00

Phillip

Island

Vic

Kirkw

oodet

al(20

05)

50

2000

00

00

1000

00

00

00

00

00

Inland

NEQld

Kutt(201

1)63

027

735

722

343

155

51

00

00

04

69

Picanniny

PlainsQld

McG

rego

ret

al(20

16)

722

2387

00

217

739

00

00

00

00

00

Mitchellgrassdo

wnsQ

ldMifsudandWoo

lley

(201

2)50

313

192

23

519

206

00

23

00

00

137

OffhamQ

ldPalmer

(unp

ubl)

435

2030

000

150

450

50

00

00

00

50

BlackallQld

Palmer

(unp

ubl)

467

2763

000

185

37

00

00

00

00

148

Mulyu

ngarieQ

ldPalmer

(unp

ubl)

350

3154

800

161

32

00

00

00

00

129

West(Pellew)Island

NT

Paltridge

etal(20

16)

545

2195

00

333

476

00

00

48

00

48

Rox

byDow

nsS

AReadandBow

en(200

1)29

430

521

607

249

456

33

23

00

00

16

Heirisson

Prong

WA

Risbeyet

al(19

99)

138

1533

300

333

333

00

00

00

00

00

Arm

idaleNSW

vanHerk(198

0)42

325

120

00

40

840

00

00

00

00

00

WitchelinaSA

Woinarski

etal(in

press)

631

442

174

16

348

305

57

38

00

02

59

Western

Qld

(boo

mperiod

)Yip

etal(20

15)

230

5080

20

600

220

20

00

00

00

60

Western

Qld

(bustperiod

)Yip

etal(20

15)

600

5413

037

315

333

37

00

00

00

148

Totals

1588

342

2548

155

55

281

299



Discussion

































Acknowledgements



References







































































































































































Sampletype

Site type Source















Sampletype

Site type Source


























2500 mm

100 mm






10 000

n o











Pet cats










Results





0

20

40

60

80

100

0 5 10 15 20 25 30


0

20

40

60

80

100

0 1000 2000 3000

Fre

quen

cy o

f rep

tiles

in c

at d

iets

(

)


(a)

(b)












Pet cats






Model DQAICc wi R2




44 003 056


46 003 056


60

10















0

1

2

3

4

5

6

0 20 40 60 80

Indi

vidu

al r

eptil

es p

er d

iet s

ampl

e



0

5

10

15

20

25

30

35

0 800 1600 2400 3200 4000

Fre

quen

cy (

)


0

3

6

9

12

0 100 200 300 400

Fre

quen

cy (

)



Wet periods only





Tab

le3

Percentag

eof

allreptile

siden

tified


yreptile

family

for

stud

iesrepo

rtingtheiden

tity

andnu

mbe

rsof

allreptile

sconsum

edby

feralcats

lsquoFreqOccrsquo

isthe

ofcatsamples

that

contained

reptileslsquoN

oreptilesrsquois

thetotalnu

mberof

reptileindividu

alsrepo

rted

incatdietary

samples

inthestud

yReptile

families

Gecko

es(C

arph

odactylidae


nidae)Pyg

op(Pyg

opod

idae)

Agam(A

gamidae)

Scinc(Scincidae)

Varan(V

aranidae)

Typ

hl(Typ

hlop

idae)

Colub

(C

olub

ridae)Boid

(Boidae)

Elap

(Elapidae)N

otethat

none

ofthelisted

stud

iesinclud

edcrocod

ilesm

arineor

freshw

ater

turtlesor

file

snakes

ascatdietaryitem

s

Location

Sou

rce

Freq

Occ

No

reptiles

Gecko

esPyg

op

Agam

Scinc

Varan

Typ

hl

Colub

Boid

Elapid

Wedge

Island

Tas

Beh

(199

5)15

800

00

00

1000

00

00

00

00

00

NingalooCapeRangeW

ADelanzyT

hompson

and

Vanderkift(unp

ubl)

400

1266

783

00

83

167

00

00

00

00

MtIsaQld

Dickm

an(unp

ubl)

462

2611

538

308

346

00

38

00

00

154

Katherine

ndashVRDN

TDickm

an(unp

ubl)

414

3339

461

30

455

00

30

00

00

30

RottnestIsland

WA

Dickm

an(unp

ubl)

219

1010

000

00

700

00

00

00

00


oppin

WA

Dickm

an(unp

ubl)

104

600

00

333

667

00

00

00

00

00

Dwelling

upW

ADickm

an(unp

ubl)

71

100

00

00

1000

00

00

00

00

00

GreatDog

Island

Tas

Hayde

(199

2)51

647

00

00

00

936

00

00

00

00

64

Flind

ersRangesSA

John

ston

etal(20

12)

292

900

00

00

1000

00

00

00

00

00

Phillip

Island

Vic

Kirkw

oodet

al(20

05)

50

2000

00

00

1000

00

00

00

00

00

Inland

NEQld

Kutt(201

1)63

027

735

722

343

155

51

00

00

04

69

Picanniny

PlainsQld

McG

rego

ret

al(20

16)

722

2387

00

217

739

00

00

00

00

00

Mitchellgrassdo

wnsQ

ldMifsudandWoo

lley

(201

2)50

313

192

23

519

206

00

23

00

00

137

OffhamQ

ldPalmer

(unp

ubl)

435

2030

000

150

450

50

00

00

00

50

BlackallQld

Palmer

(unp

ubl)

467

2763

000

185

37

00

00

00

00

148

Mulyu

ngarieQ

ldPalmer

(unp

ubl)

350

3154

800

161

32

00

00

00

00

129

West(Pellew)Island

NT

Paltridge

etal(20

16)

545

2195

00

333

476

00

00

48

00

48

Rox

byDow

nsS

AReadandBow

en(200

1)29

430

521

607

249

456

33

23

00

00

16

Heirisson

Prong

WA

Risbeyet

al(19

99)

138

1533

300

333

333

00

00

00

00

00

Arm

idaleNSW

vanHerk(198

0)42

325

120

00

40

840

00

00

00

00

00

WitchelinaSA

Woinarski

etal(in

press)

631

442

174

16

348

305

57

38

00

02

59

Western

Qld

(boo

mperiod

)Yip

etal(20

15)

230

5080

20

600

220

20

00

00

00

60

Western

Qld

(bustperiod

)Yip

etal(20

15)

600

5413

037

315

333

37

00

00

00

148

Totals

1588

342

2548

155

55

281

299



Discussion

































Acknowledgements



References






































































































































































Sampletype

Site type Source


























2500 mm

100 mm






10 000

n o











Pet cats










Results





0

20

40

60

80

100

0 5 10 15 20 25 30


0

20

40

60

80

100

0 1000 2000 3000

Fre

quen

cy o

f rep

tiles

in c

at d

iets

(

)


(a)

(b)












Pet cats






Model DQAICc wi R2




44 003 056


46 003 056


60

10















0

1

2

3

4

5

6

0 20 40 60 80

Indi

vidu

al r

eptil

es p

er d

iet s

ampl

e



0

5

10

15

20

25

30

35

0 800 1600 2400 3200 4000

Fre

quen

cy (

)


0

3

6

9

12

0 100 200 300 400

Fre

quen

cy (

)



Wet periods only





Tab

le3

Percentag

eof

allreptile

siden

tified


yreptile

family

for

stud

iesrepo

rtingtheiden

tity

andnu

mbe

rsof

allreptile

sconsum

edby

feralcats

lsquoFreqOccrsquo

isthe

ofcatsamples

that

contained

reptileslsquoN

oreptilesrsquois

thetotalnu

mberof

reptileindividu

alsrepo

rted

incatdietary

samples

inthestud

yReptile

families

Gecko

es(C

arph

odactylidae


nidae)Pyg

op(Pyg

opod

idae)

Agam(A

gamidae)

Scinc(Scincidae)

Varan(V

aranidae)

Typ

hl(Typ

hlop

idae)

Colub

(C

olub

ridae)Boid

(Boidae)

Elap

(Elapidae)N

otethat

none

ofthelisted

stud

iesinclud

edcrocod

ilesm

arineor

freshw

ater

turtlesor

file

snakes

ascatdietaryitem

s

Location

Sou

rce

Freq

Occ

No

reptiles

Gecko

esPyg

op

Agam

Scinc

Varan

Typ

hl

Colub

Boid

Elapid

Wedge

Island

Tas

Beh

(199

5)15

800

00

00

1000

00

00

00

00

00

NingalooCapeRangeW

ADelanzyT

hompson

and

Vanderkift(unp

ubl)

400

1266

783

00

83

167

00

00

00

00

MtIsaQld

Dickm

an(unp

ubl)

462

2611

538

308

346

00

38

00

00

154

Katherine

ndashVRDN

TDickm

an(unp

ubl)

414

3339

461

30

455

00

30

00

00

30

RottnestIsland

WA

Dickm

an(unp

ubl)

219

1010

000

00

700

00

00

00

00


oppin

WA

Dickm

an(unp

ubl)

104

600

00

333

667

00

00

00

00

00

Dwelling

upW

ADickm

an(unp

ubl)

71

100

00

00

1000

00

00

00

00

00

GreatDog

Island

Tas

Hayde

(199

2)51

647

00

00

00

936

00

00

00

00

64

Flind

ersRangesSA

John

ston

etal(20

12)

292

900

00

00

1000

00

00

00

00

00

Phillip

Island

Vic

Kirkw

oodet

al(20

05)

50

2000

00

00

1000

00

00

00

00

00

Inland

NEQld

Kutt(201

1)63

027

735

722

343

155

51

00

00

04

69

Picanniny

PlainsQld

McG

rego

ret

al(20

16)

722

2387

00

217

739

00

00

00

00

00

Mitchellgrassdo

wnsQ

ldMifsudandWoo

lley

(201

2)50

313

192

23

519

206

00

23

00

00

137

OffhamQ

ldPalmer

(unp

ubl)

435

2030

000

150

450

50

00

00

00

50

BlackallQld

Palmer

(unp

ubl)

467

2763

000

185

37

00

00

00

00

148

Mulyu

ngarieQ

ldPalmer

(unp

ubl)

350

3154

800

161

32

00

00

00

00

129

West(Pellew)Island

NT

Paltridge

etal(20

16)

545

2195

00

333

476

00

00

48

00

48

Rox

byDow

nsS

AReadandBow

en(200

1)29

430

521

607

249

456

33

23

00

00

16

Heirisson

Prong

WA

Risbeyet

al(19

99)

138

1533

300

333

333

00

00

00

00

00

Arm

idaleNSW

vanHerk(198

0)42

325

120

00

40

840

00

00

00

00

00

WitchelinaSA

Woinarski

etal(in

press)

631

442

174

16

348

305

57

38

00

02

59

Western

Qld

(boo

mperiod

)Yip

etal(20

15)

230

5080

20

600

220

20

00

00

00

60

Western

Qld

(bustperiod

)Yip

etal(20

15)

600

5413

037

315

333

37

00

00

00

148

Totals

1588

342

2548

155

55

281

299



Discussion

































Acknowledgements



References








































































































































































2500 mm

100 mm






10 000

n o











Pet cats










Results





0

20

40

60

80

100

0 5 10 15 20 25 30


0

20

40

60

80

100

0 1000 2000 3000

Fre

quen

cy o

f rep

tiles

in c

at d

iets

(

)


(a)

(b)












Pet cats






Model DQAICc wi R2




44 003 056


46 003 056


60

10















0

1

2

3

4

5

6

0 20 40 60 80

Indi

vidu

al r

eptil

es p

er d

iet s

ampl

e



0

5

10

15

20

25

30

35

0 800 1600 2400 3200 4000

Fre

quen

cy (

)


0

3

6

9

12

0 100 200 300 400

Fre

quen

cy (

)



Wet periods only





Tab

le3

Percentag

eof

allreptile

siden

tified


yreptile

family

for

stud

iesrepo

rtingtheiden

tity

andnu

mbe

rsof

allreptile

sconsum

edby

feralcats

lsquoFreqOccrsquo

isthe

ofcatsamples

that

contained

reptileslsquoN

oreptilesrsquois

thetotalnu

mberof

reptileindividu

alsrepo

rted

incatdietary

samples

inthestud

yReptile

families

Gecko

es(C

arph

odactylidae


nidae)Pyg

op(Pyg

opod

idae)

Agam(A

gamidae)

Scinc(Scincidae)

Varan(V

aranidae)

Typ

hl(Typ

hlop

idae)

Colub

(C

olub

ridae)Boid

(Boidae)

Elap

(Elapidae)N

otethat

none

ofthelisted

stud

iesinclud

edcrocod

ilesm

arineor

freshw

ater

turtlesor

file

snakes

ascatdietaryitem

s

Location

Sou

rce

Freq

Occ

No

reptiles

Gecko

esPyg

op

Agam

Scinc

Varan

Typ

hl

Colub

Boid

Elapid

Wedge

Island

Tas

Beh

(199

5)15

800

00

00

1000

00

00

00

00

00

NingalooCapeRangeW

ADelanzyT

hompson

and

Vanderkift(unp

ubl)

400

1266

783

00

83

167

00

00

00

00

MtIsaQld

Dickm

an(unp

ubl)

462

2611

538

308

346

00

38

00

00

154

Katherine

ndashVRDN

TDickm

an(unp

ubl)

414

3339

461

30

455

00

30

00

00

30

RottnestIsland

WA

Dickm

an(unp

ubl)

219

1010

000

00

700

00

00

00

00


oppin

WA

Dickm

an(unp

ubl)

104

600

00

333

667

00

00

00

00

00

Dwelling

upW

ADickm

an(unp

ubl)

71

100

00

00

1000

00

00

00

00

00

GreatDog

Island

Tas

Hayde

(199

2)51

647

00

00

00

936

00

00

00

00

64

Flind

ersRangesSA

John

ston

etal(20

12)

292

900

00

00

1000

00

00

00

00

00

Phillip

Island

Vic

Kirkw

oodet

al(20

05)

50

2000

00

00

1000

00

00

00

00

00

Inland

NEQld

Kutt(201

1)63

027

735

722

343

155

51

00

00

04

69

Picanniny

PlainsQld

McG

rego

ret

al(20

16)

722

2387

00

217

739

00

00

00

00

00

Mitchellgrassdo

wnsQ

ldMifsudandWoo

lley

(201

2)50

313

192

23

519

206

00

23

00

00

137

OffhamQ

ldPalmer

(unp

ubl)

435

2030

000

150

450

50

00

00

00

50

BlackallQld

Palmer

(unp

ubl)

467

2763

000

185

37

00

00

00

00

148

Mulyu

ngarieQ

ldPalmer

(unp

ubl)

350

3154

800

161

32

00

00

00

00

129

West(Pellew)Island

NT

Paltridge

etal(20

16)

545

2195

00

333

476

00

00

48

00

48

Rox

byDow

nsS

AReadandBow

en(200

1)29

430

521

607

249

456

33

23

00

00

16

Heirisson

Prong

WA

Risbeyet

al(19

99)

138

1533

300

333

333

00

00

00

00

00

Arm

idaleNSW

vanHerk(198

0)42

325

120

00

40

840

00

00

00

00

00

WitchelinaSA

Woinarski

etal(in

press)

631

442

174

16

348

305

57

38

00

02

59

Western

Qld

(boo

mperiod

)Yip

etal(20

15)

230

5080

20

600

220

20

00

00

00

60

Western

Qld

(bustperiod

)Yip

etal(20

15)

600

5413

037

315

333

37

00

00

00

148

Totals

1588

342

2548

155

55

281

299



Discussion

































Acknowledgements



References




































































































































































10 000

n o











Pet cats










Results





0

20

40

60

80

100

0 5 10 15 20 25 30


0

20

40

60

80

100

0 1000 2000 3000

Fre

quen

cy o

f rep

tiles

in c

at d

iets

(

)


(a)

(b)












Pet cats






Model DQAICc wi R2




44 003 056


46 003 056


60

10















0

1

2

3

4

5

6

0 20 40 60 80

Indi

vidu

al r

eptil

es p

er d

iet s

ampl

e



0

5

10

15

20

25

30

35

0 800 1600 2400 3200 4000

Fre

quen

cy (

)


0

3

6

9

12

0 100 200 300 400

Fre

quen

cy (

)



Wet periods only





Tab

le3

Percentag

eof

allreptile

siden

tified


yreptile

family

for

stud

iesrepo

rtingtheiden

tity

andnu

mbe

rsof

allreptile

sconsum

edby

feralcats

lsquoFreqOccrsquo

isthe

ofcatsamples

that

contained

reptileslsquoN

oreptilesrsquois

thetotalnu

mberof

reptileindividu

alsrepo

rted

incatdietary

samples

inthestud

yReptile

families

Gecko

es(C

arph

odactylidae


nidae)Pyg

op(Pyg

opod

idae)

Agam(A

gamidae)

Scinc(Scincidae)

Varan(V

aranidae)

Typ

hl(Typ

hlop

idae)

Colub

(C

olub

ridae)Boid

(Boidae)

Elap

(Elapidae)N

otethat

none

ofthelisted

stud

iesinclud

edcrocod

ilesm

arineor

freshw

ater

turtlesor

file

snakes

ascatdietaryitem

s

Location

Sou

rce

Freq

Occ

No

reptiles

Gecko

esPyg

op

Agam

Scinc

Varan

Typ

hl

Colub

Boid

Elapid

Wedge

Island

Tas

Beh

(199

5)15

800

00

00

1000

00

00

00

00

00

NingalooCapeRangeW

ADelanzyT

hompson

and

Vanderkift(unp

ubl)

400

1266

783

00

83

167

00

00

00

00

MtIsaQld

Dickm

an(unp

ubl)

462

2611

538

308

346

00

38

00

00

154

Katherine

ndashVRDN

TDickm

an(unp

ubl)

414

3339

461

30

455

00

30

00

00

30

RottnestIsland

WA

Dickm

an(unp

ubl)

219

1010

000

00

700

00

00

00

00


oppin

WA

Dickm

an(unp

ubl)

104

600

00

333

667

00

00

00

00

00

Dwelling

upW

ADickm

an(unp

ubl)

71

100

00

00

1000

00

00

00

00

00

GreatDog

Island

Tas

Hayde

(199

2)51

647

00

00

00

936

00

00

00

00

64

Flind

ersRangesSA

John

ston

etal(20

12)

292

900

00

00

1000

00

00

00

00

00

Phillip

Island

Vic

Kirkw

oodet

al(20

05)

50

2000

00

00

1000

00

00

00

00

00

Inland

NEQld

Kutt(201

1)63

027

735

722

343

155

51

00

00

04

69

Picanniny

PlainsQld

McG

rego

ret

al(20

16)

722

2387

00

217

739

00

00

00

00

00

Mitchellgrassdo

wnsQ

ldMifsudandWoo

lley

(201

2)50

313

192

23

519

206

00

23

00

00

137

OffhamQ

ldPalmer

(unp

ubl)

435

2030

000

150

450

50

00

00

00

50

BlackallQld

Palmer

(unp

ubl)

467

2763

000

185

37

00

00

00

00

148

Mulyu

ngarieQ

ldPalmer

(unp

ubl)

350

3154

800

161

32

00

00

00

00

129

West(Pellew)Island

NT

Paltridge

etal(20

16)

545

2195

00

333

476

00

00

48

00

48

Rox

byDow

nsS

AReadandBow

en(200

1)29

430

521

607

249

456

33

23

00

00

16

Heirisson

Prong

WA

Risbeyet

al(19

99)

138

1533

300

333

333

00

00

00

00

00

Arm

idaleNSW

vanHerk(198

0)42

325

120

00

40

840

00

00

00

00

00

WitchelinaSA

Woinarski

etal(in

press)

631

442

174

16

348

305

57

38

00

02

59

Western

Qld

(boo

mperiod

)Yip

etal(20

15)

230

5080

20

600

220

20

00

00

00

60

Western

Qld

(bustperiod

)Yip

etal(20

15)

600

5413

037

315

333

37

00

00

00

148

Totals

1588

342

2548

155

55

281

299



Discussion

































Acknowledgements



References








































































































































































Results





0

20

40

60

80

100

0 5 10 15 20 25 30


0

20

40

60

80

100

0 1000 2000 3000

Fre

quen

cy o

f rep

tiles

in c

at d

iets

(

)


(a)

(b)












Pet cats






Model DQAICc wi R2




44 003 056


46 003 056


60

10















0

1

2

3

4

5

6

0 20 40 60 80

Indi

vidu

al r

eptil

es p

er d

iet s

ampl

e



0

5

10

15

20

25

30

35

0 800 1600 2400 3200 4000

Fre

quen

cy (

)


0

3

6

9

12

0 100 200 300 400

Fre

quen

cy (

)



Wet periods only





Tab

le3

Percentag

eof

allreptile

siden

tified


yreptile

family

for

stud

iesrepo

rtingtheiden

tity

andnu

mbe

rsof

allreptile

sconsum

edby

feralcats

lsquoFreqOccrsquo

isthe

ofcatsamples

that

contained

reptileslsquoN

oreptilesrsquois

thetotalnu

mberof

reptileindividu

alsrepo

rted

incatdietary

samples

inthestud

yReptile

families

Gecko

es(C

arph

odactylidae


nidae)Pyg

op(Pyg

opod

idae)

Agam(A

gamidae)

Scinc(Scincidae)

Varan(V

aranidae)

Typ

hl(Typ

hlop

idae)

Colub

(C

olub

ridae)Boid

(Boidae)

Elap

(Elapidae)N

otethat

none

ofthelisted

stud

iesinclud

edcrocod

ilesm

arineor

freshw

ater

turtlesor

file

snakes

ascatdietaryitem

s

Location

Sou

rce

Freq

Occ

No

reptiles

Gecko

esPyg

op

Agam

Scinc

Varan

Typ

hl

Colub

Boid

Elapid

Wedge

Island

Tas

Beh

(199

5)15

800

00

00

1000

00

00

00

00

00

NingalooCapeRangeW

ADelanzyT

hompson

and

Vanderkift(unp

ubl)

400

1266

783

00

83

167

00

00

00

00

MtIsaQld

Dickm

an(unp

ubl)

462

2611

538

308

346

00

38

00

00

154

Katherine

ndashVRDN

TDickm

an(unp

ubl)

414

3339

461

30

455

00

30

00

00

30

RottnestIsland

WA

Dickm

an(unp

ubl)

219

1010

000

00

700

00

00

00

00


oppin

WA

Dickm

an(unp

ubl)

104

600

00

333

667

00

00

00

00

00

Dwelling

upW

ADickm

an(unp

ubl)

71

100

00

00

1000

00

00

00

00

00

GreatDog

Island

Tas

Hayde

(199

2)51

647

00

00

00

936

00

00

00

00

64

Flind

ersRangesSA

John

ston

etal(20

12)

292

900

00

00

1000

00

00

00

00

00

Phillip

Island

Vic

Kirkw

oodet

al(20

05)

50

2000

00

00

1000

00

00

00

00

00

Inland

NEQld

Kutt(201

1)63

027

735

722

343

155

51

00

00

04

69

Picanniny

PlainsQld

McG

rego

ret

al(20

16)

722

2387

00

217

739

00

00

00

00

00

Mitchellgrassdo

wnsQ

ldMifsudandWoo

lley

(201

2)50

313

192

23

519

206

00

23

00

00

137

OffhamQ

ldPalmer

(unp

ubl)

435

2030

000

150

450

50

00

00

00

50

BlackallQld

Palmer

(unp

ubl)

467

2763

000

185

37

00

00

00

00

148

Mulyu

ngarieQ

ldPalmer

(unp

ubl)

350

3154

800

161

32

00

00

00

00

129

West(Pellew)Island

NT

Paltridge

etal(20

16)

545

2195

00

333

476

00

00

48

00

48

Rox

byDow

nsS

AReadandBow

en(200

1)29

430

521

607

249

456

33

23

00

00

16

Heirisson

Prong

WA

Risbeyet

al(19

99)

138

1533

300

333

333

00

00

00

00

00

Arm

idaleNSW

vanHerk(198

0)42

325

120

00

40

840

00

00

00

00

00

WitchelinaSA

Woinarski

etal(in

press)

631

442

174

16

348

305

57

38

00

02

59

Western

Qld

(boo

mperiod

)Yip

etal(20

15)

230

5080

20

600

220

20

00

00

00

60

Western

Qld

(bustperiod

)Yip

etal(20

15)

600

5413

037

315

333

37

00

00

00

148

Totals

1588

342

2548

155

55

281

299



Discussion

































Acknowledgements



References











































































































































































Pet cats






Model DQAICc wi R2




44 003 056


46 003 056


60

10















0

1

2

3

4

5

6

0 20 40 60 80

Indi

vidu

al r

eptil

es p

er d

iet s

ampl

e



0

5

10

15

20

25

30

35

0 800 1600 2400 3200 4000

Fre

quen

cy (

)


0

3

6

9

12

0 100 200 300 400

Fre

quen

cy (

)



Wet periods only





Tab

le3

Percentag

eof

allreptile

siden

tified


yreptile

family

for

stud

iesrepo

rtingtheiden

tity

andnu

mbe

rsof

allreptile

sconsum

edby

feralcats

lsquoFreqOccrsquo

isthe

ofcatsamples

that

contained

reptileslsquoN

oreptilesrsquois

thetotalnu

mberof

reptileindividu

alsrepo

rted

incatdietary

samples

inthestud

yReptile

families

Gecko

es(C

arph

odactylidae


nidae)Pyg

op(Pyg

opod

idae)

Agam(A

gamidae)

Scinc(Scincidae)

Varan(V

aranidae)

Typ

hl(Typ

hlop

idae)

Colub

(C

olub

ridae)Boid

(Boidae)

Elap

(Elapidae)N

otethat

none

ofthelisted

stud

iesinclud

edcrocod

ilesm

arineor

freshw

ater

turtlesor

file

snakes

ascatdietaryitem

s

Location

Sou

rce

Freq

Occ

No

reptiles

Gecko

esPyg

op

Agam

Scinc

Varan

Typ

hl

Colub

Boid

Elapid

Wedge

Island

Tas

Beh

(199

5)15

800

00

00

1000

00

00

00

00

00

NingalooCapeRangeW

ADelanzyT

hompson

and

Vanderkift(unp

ubl)

400

1266

783

00

83

167

00

00

00

00

MtIsaQld

Dickm

an(unp

ubl)

462

2611

538

308

346

00

38

00

00

154

Katherine

ndashVRDN

TDickm

an(unp

ubl)

414

3339

461

30

455

00

30

00

00

30

RottnestIsland

WA

Dickm

an(unp

ubl)

219

1010

000

00

700

00

00

00

00


oppin

WA

Dickm

an(unp

ubl)

104

600

00

333

667

00

00

00

00

00

Dwelling

upW

ADickm

an(unp

ubl)

71

100

00

00

1000

00

00

00

00

00

GreatDog

Island

Tas

Hayde

(199

2)51

647

00

00

00

936

00

00

00

00

64

Flind

ersRangesSA

John

ston

etal(20

12)

292

900

00

00

1000

00

00

00

00

00

Phillip

Island

Vic

Kirkw

oodet

al(20

05)

50

2000

00

00

1000

00

00

00

00

00

Inland

NEQld

Kutt(201

1)63

027

735

722

343

155

51

00

00

04

69

Picanniny

PlainsQld

McG

rego

ret

al(20

16)

722

2387

00

217

739

00

00

00

00

00

Mitchellgrassdo

wnsQ

ldMifsudandWoo

lley

(201

2)50

313

192

23

519

206

00

23

00

00

137

OffhamQ

ldPalmer

(unp

ubl)

435

2030

000

150

450

50

00

00

00

50

BlackallQld

Palmer

(unp

ubl)

467

2763

000

185

37

00

00

00

00

148

Mulyu

ngarieQ

ldPalmer

(unp

ubl)

350

3154

800

161

32

00

00

00

00

129

West(Pellew)Island

NT

Paltridge

etal(20

16)

545

2195

00

333

476

00

00

48

00

48

Rox

byDow

nsS

AReadandBow

en(200

1)29

430

521

607

249

456

33

23

00

00

16

Heirisson

Prong

WA

Risbeyet

al(19

99)

138

1533

300

333

333

00

00

00

00

00

Arm

idaleNSW

vanHerk(198

0)42

325

120

00

40

840

00

00

00

00

00

WitchelinaSA

Woinarski

etal(in

press)

631

442

174

16

348

305

57

38

00

02

59

Western

Qld

(boo

mperiod

)Yip

etal(20

15)

230

5080

20

600

220

20

00

00

00

60

Western

Qld

(bustperiod

)Yip

etal(20

15)

600

5413

037

315

333

37

00

00

00

148

Totals

1588

342

2548

155

55

281

299



Discussion

































Acknowledgements



References


































































































































































60

10















0

1

2

3

4

5

6

0 20 40 60 80

Indi

vidu

al r

eptil

es p

er d

iet s

ampl

e



0

5

10

15

20

25

30

35

0 800 1600 2400 3200 4000

Fre

quen

cy (

)


0

3

6

9

12

0 100 200 300 400

Fre

quen

cy (

)



Wet periods only





Tab

le3

Percentag

eof

allreptile

siden

tified


yreptile

family

for

stud

iesrepo

rtingtheiden

tity

andnu

mbe

rsof

allreptile

sconsum

edby

feralcats

lsquoFreqOccrsquo

isthe

ofcatsamples

that

contained

reptileslsquoN

oreptilesrsquois

thetotalnu

mberof

reptileindividu

alsrepo

rted

incatdietary

samples

inthestud

yReptile

families

Gecko

es(C

arph

odactylidae


nidae)Pyg

op(Pyg

opod

idae)

Agam(A

gamidae)

Scinc(Scincidae)

Varan(V

aranidae)

Typ

hl(Typ

hlop

idae)

Colub

(C

olub

ridae)Boid

(Boidae)

Elap

(Elapidae)N

otethat

none

ofthelisted

stud

iesinclud

edcrocod

ilesm

arineor

freshw

ater

turtlesor

file

snakes

ascatdietaryitem

s

Location

Sou

rce

Freq

Occ

No

reptiles

Gecko

esPyg

op

Agam

Scinc

Varan

Typ

hl

Colub

Boid

Elapid

Wedge

Island

Tas

Beh

(199

5)15

800

00

00

1000

00

00

00

00

00

NingalooCapeRangeW

ADelanzyT

hompson

and

Vanderkift(unp

ubl)

400

1266

783

00

83

167

00

00

00

00

MtIsaQld

Dickm

an(unp

ubl)

462

2611

538

308

346

00

38

00

00

154

Katherine

ndashVRDN

TDickm

an(unp

ubl)

414

3339

461

30

455

00

30

00

00

30

RottnestIsland

WA

Dickm

an(unp

ubl)

219

1010

000

00

700

00

00

00

00


oppin

WA

Dickm

an(unp

ubl)

104

600

00

333

667

00

00

00

00

00

Dwelling

upW

ADickm

an(unp

ubl)

71

100

00

00

1000

00

00

00

00

00

GreatDog

Island

Tas

Hayde

(199

2)51

647

00

00

00

936

00

00

00

00

64

Flind

ersRangesSA

John

ston

etal(20

12)

292

900

00

00

1000

00

00

00

00

00

Phillip

Island

Vic

Kirkw

oodet

al(20

05)

50

2000

00

00

1000

00

00

00

00

00

Inland

NEQld

Kutt(201

1)63

027

735

722

343

155

51

00

00

04

69

Picanniny

PlainsQld

McG

rego

ret

al(20

16)

722

2387

00

217

739

00

00

00

00

00

Mitchellgrassdo

wnsQ

ldMifsudandWoo

lley

(201

2)50

313

192

23

519

206

00

23

00

00

137

OffhamQ

ldPalmer

(unp

ubl)

435

2030

000

150

450

50

00

00

00

50

BlackallQld

Palmer

(unp

ubl)

467

2763

000

185

37

00

00

00

00

148

Mulyu

ngarieQ

ldPalmer

(unp

ubl)

350

3154

800

161

32

00

00

00

00

129

West(Pellew)Island

NT

Paltridge

etal(20

16)

545

2195

00

333

476

00

00

48

00

48

Rox

byDow

nsS

AReadandBow

en(200

1)29

430

521

607

249

456

33

23

00

00

16

Heirisson

Prong

WA

Risbeyet

al(19

99)

138

1533

300

333

333

00

00

00

00

00

Arm

idaleNSW

vanHerk(198

0)42

325

120

00

40

840

00

00

00

00

00

WitchelinaSA

Woinarski

etal(in

press)

631

442

174

16

348

305

57

38

00

02

59

Western

Qld

(boo

mperiod

)Yip

etal(20

15)

230

5080

20

600

220

20

00

00

00

60

Western

Qld

(bustperiod

)Yip

etal(20

15)

600

5413

037

315

333

37

00

00

00

148

Totals

1588

342

2548

155

55

281

299



Discussion

































Acknowledgements



References










































































































































































0

1

2

3

4

5

6

0 20 40 60 80

Indi

vidu

al r

eptil

es p

er d

iet s

ampl

e



0

5

10

15

20

25

30

35

0 800 1600 2400 3200 4000

Fre

quen

cy (

)


0

3

6

9

12

0 100 200 300 400

Fre

quen

cy (

)



Wet periods only





Tab

le3

Percentag

eof

allreptile

siden

tified


yreptile

family

for

stud

iesrepo

rtingtheiden

tity

andnu

mbe

rsof

allreptile

sconsum

edby

feralcats

lsquoFreqOccrsquo

isthe

ofcatsamples

that

contained

reptileslsquoN

oreptilesrsquois

thetotalnu

mberof

reptileindividu

alsrepo

rted

incatdietary

samples

inthestud

yReptile

families

Gecko

es(C

arph

odactylidae


nidae)Pyg

op(Pyg

opod

idae)

Agam(A

gamidae)

Scinc(Scincidae)

Varan(V

aranidae)

Typ

hl(Typ

hlop

idae)

Colub

(C

olub

ridae)Boid

(Boidae)

Elap

(Elapidae)N

otethat

none

ofthelisted

stud

iesinclud

edcrocod

ilesm

arineor

freshw

ater

turtlesor

file

snakes

ascatdietaryitem

s

Location

Sou

rce

Freq

Occ

No

reptiles

Gecko

esPyg

op

Agam

Scinc

Varan

Typ

hl

Colub

Boid

Elapid

Wedge

Island

Tas

Beh

(199

5)15

800

00

00

1000

00

00

00

00

00

NingalooCapeRangeW

ADelanzyT

hompson

and

Vanderkift(unp

ubl)

400

1266

783

00

83

167

00

00

00

00

MtIsaQld

Dickm

an(unp

ubl)

462

2611

538

308

346

00

38

00

00

154

Katherine

ndashVRDN

TDickm

an(unp

ubl)

414

3339

461

30

455

00

30

00

00

30

RottnestIsland

WA

Dickm

an(unp

ubl)

219

1010

000

00

700

00

00

00

00


oppin

WA

Dickm

an(unp

ubl)

104

600

00

333

667

00

00

00

00

00

Dwelling

upW

ADickm

an(unp

ubl)

71

100

00

00

1000

00

00

00

00

00

GreatDog

Island

Tas

Hayde

(199

2)51

647

00

00

00

936

00

00

00

00

64

Flind

ersRangesSA

John

ston

etal(20

12)

292

900

00

00

1000

00

00

00

00

00

Phillip

Island

Vic

Kirkw

oodet

al(20

05)

50

2000

00

00

1000

00

00

00

00

00

Inland

NEQld

Kutt(201

1)63

027

735

722

343

155

51

00

00

04

69

Picanniny

PlainsQld

McG

rego

ret

al(20

16)

722

2387

00

217

739

00

00

00

00

00

Mitchellgrassdo

wnsQ

ldMifsudandWoo

lley

(201

2)50

313

192

23

519

206

00

23

00

00

137

OffhamQ

ldPalmer

(unp

ubl)

435

2030

000

150

450

50

00

00

00

50

BlackallQld

Palmer

(unp

ubl)

467

2763

000

185

37

00

00

00

00

148

Mulyu

ngarieQ

ldPalmer

(unp

ubl)

350

3154

800

161

32

00

00

00

00

129

West(Pellew)Island

NT

Paltridge

etal(20

16)

545

2195

00

333

476

00

00

48

00

48

Rox

byDow

nsS

AReadandBow

en(200

1)29

430

521

607

249

456

33

23

00

00

16

Heirisson

Prong

WA

Risbeyet

al(19

99)

138

1533

300

333

333

00

00

00

00

00

Arm

idaleNSW

vanHerk(198

0)42

325

120

00

40

840

00

00

00

00

00

WitchelinaSA

Woinarski

etal(in

press)

631

442

174

16

348

305

57

38

00

02

59

Western

Qld

(boo

mperiod

)Yip

etal(20

15)

230

5080

20

600

220

20

00

00

00

60

Western

Qld

(bustperiod

)Yip

etal(20

15)

600

5413

037

315

333

37

00

00

00

148

Totals

1588

342

2548

155

55

281

299



Discussion

































Acknowledgements



References


































































































































































Tab

le3

Percentag

eof

allreptile

siden

tified


yreptile

family

for

stud

iesrepo

rtingtheiden

tity

andnu

mbe

rsof

allreptile

sconsum

edby

feralcats

lsquoFreqOccrsquo

isthe

ofcatsamples

that

contained

reptileslsquoN

oreptilesrsquois

thetotalnu

mberof

reptileindividu

alsrepo

rted

incatdietary

samples

inthestud

yReptile

families

Gecko

es(C

arph

odactylidae


nidae)Pyg

op(Pyg

opod

idae)

Agam(A

gamidae)

Scinc(Scincidae)

Varan(V

aranidae)

Typ

hl(Typ

hlop

idae)

Colub

(C

olub

ridae)Boid

(Boidae)

Elap

(Elapidae)N

otethat

none

ofthelisted

stud

iesinclud

edcrocod

ilesm

arineor

freshw

ater

turtlesor

file

snakes

ascatdietaryitem

s

Location

Sou

rce

Freq

Occ

No

reptiles

Gecko

esPyg

op

Agam

Scinc

Varan

Typ

hl

Colub

Boid

Elapid

Wedge

Island

Tas

Beh

(199

5)15

800

00

00

1000

00

00

00

00

00

NingalooCapeRangeW

ADelanzyT

hompson

and

Vanderkift(unp

ubl)

400

1266

783

00

83

167

00

00

00

00

MtIsaQld

Dickm

an(unp

ubl)

462

2611

538

308

346

00

38

00

00

154

Katherine

ndashVRDN

TDickm

an(unp

ubl)

414

3339

461

30

455

00

30

00

00

30

RottnestIsland

WA

Dickm

an(unp

ubl)

219

1010

000

00

700

00

00

00

00


oppin

WA

Dickm

an(unp

ubl)

104

600

00

333

667

00

00

00

00

00

Dwelling

upW

ADickm

an(unp

ubl)

71

100

00

00

1000

00

00

00

00

00

GreatDog

Island

Tas

Hayde

(199

2)51

647

00

00

00

936

00

00

00

00

64

Flind

ersRangesSA

John

ston

etal(20

12)

292

900

00

00

1000

00

00

00

00

00

Phillip

Island

Vic

Kirkw

oodet

al(20

05)

50

2000

00

00

1000

00

00

00

00

00

Inland

NEQld

Kutt(201

1)63

027

735

722

343

155

51

00

00

04

69

Picanniny

PlainsQld

McG

rego

ret

al(20

16)

722

2387

00

217

739

00

00

00

00

00

Mitchellgrassdo

wnsQ

ldMifsudandWoo

lley

(201

2)50

313

192

23

519

206

00

23

00

00

137

OffhamQ

ldPalmer

(unp

ubl)

435

2030

000

150

450

50

00

00

00

50

BlackallQld

Palmer

(unp

ubl)

467

2763

000

185

37

00

00

00

00

148

Mulyu

ngarieQ

ldPalmer

(unp

ubl)

350

3154

800

161

32

00

00

00

00

129

West(Pellew)Island

NT

Paltridge

etal(20

16)

545

2195

00

333

476

00

00

48

00

48

Rox

byDow

nsS

AReadandBow

en(200

1)29

430

521

607

249

456

33

23

00

00

16

Heirisson

Prong

WA

Risbeyet

al(19

99)

138

1533

300

333

333

00

00

00

00

00

Arm

idaleNSW

vanHerk(198

0)42

325

120

00

40

840

00

00

00

00

00

WitchelinaSA

Woinarski

etal(in

press)

631

442

174

16

348

305

57

38

00

02

59

Western

Qld

(boo

mperiod

)Yip

etal(20

15)

230

5080

20

600

220

20

00

00

00

60

Western

Qld

(bustperiod

)Yip

etal(20

15)

600

5413

037

315

333

37

00

00

00

148

Totals

1588

342

2548

155

55

281

299



Discussion

































Acknowledgements



References



































































































































































Discussion

































Acknowledgements



References
























































































































































































Acknowledgements



References


































































































































































how many reptiles are killed by cats in australia?reptiles in diet (n) % native reptiles/all...

Documents