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Social and Mating among Core Groups E l fM l H i (“T i ”) Kill Wh l Social and Mating among Core Groups E l fM l H ti (“T i t”) Kill Wh l Ecology of Mammal Hunting (“Transient”) Killer Whales Ecology of Mammal Hunting (“Transient”) Killer Whales Ecology of Mammal-Hunting ( Transient ) Killer Whales Ecology of Mammal-Hunting ( Transient ) Killer Whales Ecology of Mammal Hunting ( Transient ) Killer Whales Ecology of Mammal Hunting ( Transient ) Killer Whales i C if i A 22 S i M t B C lif i A 22 Y St d in Montere Ba California: A 22 Year St d in Monterey Bay California: A 22 Year Study in Monterey Bay California: A 22-Year Study in Monterey Bay, California: A 22-Year Study in Monterey Bay, California: A 22 Year Study in Monterey Bay, California: A 22 Year Study N Bl k ( b hl@ l ) Ri h dT ll M B C P j PO B 52001 P ifi G CA 93950 Nancy Black (mbaywhale@aol com) Richard Ternullo; Monterey Bay Cetacean Project PO Box 52001 Pacific Grove CA 93950 Nancy Black (mbaywhale@aol com) Richard Ternullo; Monterey Bay Cetacean Project PO Box 52001 Pacific Grove CA 93950 Nancy Black ([email protected]), Richard Ternullo; Monterey Bay Cetacean Project, P.O. Box 52001, Pacific Grove, CA 93950 G th fM l Kill Wh l O 16 Y Growth of Male Killer Whales Over 16 Years C f Mi i G Wh l Cl (f WP /NMFS) ABSTRACT Growth of Male Killer Whales Over 16 Years Counts of Migrating Gray Whale Calves (from W Perryman/NMFS) ABSTRACT Counts of Migrating Gray Whale Calves (from W. Perryman/NMFS) ABSTRACT Counts of Migrating Gray Whale Calves (from W. Perryman/NMFS) Since 1987 we photo identified whales recorded location prey type behaviors and collected 01 02 92 99 06 D (b h) O l db Kill Wh l Si hti Dt ( d) Since 1987 we photo-identified whales, recorded location, prey type, behaviors and collected 01 02 92 99 06 per Day (bar graph) Over layed by Killer Whale Sighting Dates (red) bi l db d i l i l i l 92 99 06 per Day (bar graph) Over -layed by Killer Whale Sighting Dates (red) biopsy samples on year -round boat surveys to determine population parameters ecological per Day (bar graph) Over layed by Killer Whale Sighting Dates (red) biopsy samples on year -round boat surveys to determine population parameters, ecological d Att kD t (bl )b Y ( l t l ) tt d t i tl l f kill hl T i t i ht d 545 d d and Attack Dates (blue) by Year (select examples) patterns, and contaminant levels of killer whales. Transients were sighted on 545 days, and and Attack Dates (blue) by Year (select examples) patterns, and contaminant levels of killer whales. Transients were sighted on 545 days, and 154 individuals were identified (from 1 to 80 times each) over 20 years with a current L d 154 individuals were identified (from 1 to 80 times each) over 20 years with a current Legend: l ti f 112 hl (22% d ti f l 11% t d ti f l 20% 2005 (calf count=345) 2005 ( lf t 345) Legend: 2001 (calf count = 87) 2001 ( lf t 87) population of 112 whales (22% reproductive females, 11% post reproductive females, 20% O X 2005 (calf count=345) 2005 (calf count=345) Bars number of calves/day 2001 (calf count=87) population of 112 whales (22% reproductive females, 11% post reproductive females, 20% X 2005 (calf count=345) Bars = number of calves/day 2001 (calf count=87) adult males) Whales frequented the canyon edge in Monterey Bay and were re sighted from 45 45 adult males). Whales frequented the canyon edge in Monterey Bay and were re-sighted from 45 h C lif i S h Al k Th l i i d f i d 40 = killer whale sightings 40 southern California to Southeast Alaska The population consisted of core groups comprised 40 = killer whale sightings, 40 southern California to Southeast Alaska. The population consisted of core groups comprised X X X X O OX size of oval relative to 35 of 1 3 adult females and their offspring Calving interval ranged from 5 to 10 years These 35 X X X X X O OX size of oval relative to 35 X of 1-3 adult females and their offspring. Calving interval ranged from 5 to 10 years. These i (5 10 15 20 25) 00 02 92 94 96 08 30 group size (5, 10,15, 20, 25) 30 whales (n=9) were highly contaminated with POPs which could contribute to a low 00 02 92 94 96 08 30 group size (5, 10,15, 20, 25) whales (n=9) were highly contaminated with POPs, which could contribute to a low 02 94 96 08 25 25 d ti t dhi h t lit l lM l PCB 87 888 / 25 predation events by killer 25 reproductive rate and higher mortality level. Mean values were PCBs: 87,888ng/g; 20 = predation events by killer 20 reproductive rate and higher mortality level. Mean values were PCBs: 87,888ng/g; 20 hl hl l 20 DDTs: 507 148; PBDEs: 15 000 which is among the highest levels recorded for whales on gray whale calves 15 DDTs: 507,148; PBDEs: 15,000 which is among the highest levels recorded for 15 whales on gray whale calves 15 K h (2007) d ld l ( 4) PCB 630 000 DDT (X in center is attack) cetaceans Krahn (2007) reported on our sampled males (n=4); PCBs: 630 000; DDTs: F Gohier 10 (X in center is attack) 10 cetaceans. Krahn (2007) reported on our sampled males (n=4); PCBs: 630,000; DDTs: F. Gohier 10 (O in center is escape) 10 3 700 000; PBDEs: 12 600 We observed 123 predation events on nine species of 5 (O in center is escape) 5 3,700,000; PBDEs: 12,600. We observed 123 predation events on nine species of 5 5 l Wh l d db f ihl i 0 0 mammals Whales occurred year -round but were most frequent with largest group sizes 0 0 mammals. Whales occurred year -round but were most frequent with largest group sizes S d A M B 20 23 26 29 /1 /4 /7 10 13 16 19 22 25 28 /1 /4 /7 10 13 16 19 22 25 28 31 /3 /6 0 5 0 4 9 4 9 4 9 4 9 4 9 4 9 3 ( 12) i d i i di t th i ti f th / lf Study Area: Monterey Bay /2 /2 /2 /2 4/ 4/ 4/ /1 /1 /1 /1 /2 /2 /2 5/ 5/ 5/ /1 /1 /1 /1 /2 /2 /2 /3 6/ 6/ G Wh l /20 /25 /30 4/4 4/9 /14 /19 /24 /29 5/4 5/9 /14 /19 /24 /29 6/3 (mean=12) occurring during spring, corresponding to the migration of mother/calf gray Study Area: Monterey Bay 3 3 3 3 4 4 4 4 4 4 4 5 5 5 5 5 5 5 5 Gray Whale 3/ 3/ 3/ 4 4 4/ 4/ 4/ 4/ 5/ 5/ 5/ 5/ Study Area: Monterey Bay 2004 (calf count = 559 1998 ( lf t 440) Gray Whale whales Fifty four predation events on gray whale calves were recorded 1 to 5 core groups A dS b i C N b fS ii Cl 2004 (calf count = 559 1998 (calf count = 440) 2004 ( lf t 650) whales. Fifty-four predation events on gray whale calves were recorded, 1 to 5 core groups And Submarine Canyon Percent Number of Sightings Number of Surviving Calves 2004 (calf count=650) M th /C lf Mi ti i l dj t2 3f l t ti i th tt k d hl kill d d And Submarine Canyon Percent Number of Sightings Number of Surviving Calves, 45 X 45 2004 (calf count=650) Mother/Calf Migration 1998 (calf count=440) were involved, just 2-3 females were most active in the attack, and some whales killed and Percent Number of Sightings Number of Surviving Calves, 45 X O O X X X X X X XO X X O 45 Mother/Calf Migration 1998 (calf count=440) were involved, just 2 3 females were most active in the attack, and some whales killed and Cli It l dN b 40 X O O X X X X X XO X X O G hl l db fed on 6 gray whales over 21 days The number of attacks (0 11/yr) corresponded to the and Mean Group Size of Killer Calving Interval and Number 40 40 X Gray whale calves were counted by fed on 6 gray whales over 21 days. The number of attacks (0-11/yr) corresponded to the and Mean Group Size of Killer Calving Interval, and Number 35 X Gray whale calves were counted by b f hl l b h (87 559 WP /NMFS) C l l and Mean Group Size of Killer 35 35 O X X W P (NMFS) number of gray whale calves born each year (87 to 559; per W Perryman/NMFS) Cultural (199 200 ) f Si hti Y F F l 30 35 O X Wayne Perryman’s group (NMFS) number of gray whale calves born each year (87 to 559; per W. Perryman/NMFS). Cultural Whales by Month (1997 2007) of Sighting Years For Females 30 30 Wayne Perryman s group (NMFS) transmission of spatial/temporal timing is evident and the bathymetric features of the canyon Whales by Month (1997-2007) of Sighting Years For Females 25 30 from Pt Piedras Blancas (64 km south transmission of spatial/temporal timing is evident and the bathymetric features of the canyon Whales by Month (1997 2007) 25 25 from Pt. Piedras Blancas (64 km south 20 25 fM t ) Kill hl i hti appear advantageous to foraging killer whales 20 20 of Monterey). Killer whale sightings appear advantageous to foraging killer whales. Percent Number Sightings Per Month (9 _ 15 20 of Monterey). Killer whale sightings Percent Number Sightings Per Month (9 D il i i ( hl Whale Surviving X Calving # Years 15 and attacks were documented in Daily opportunistic (whale Whale Surviving X Calving # Years 15 15 and attacks were documented in 0 18 Daily opportunistic (whale 10 M B N b f hl 0.18 73 watch vessel) and periodic T i t Kill Wh l P l ti dR # Calves Interval Sighted 10 10 Monterey Bay Number of gray whale 0 16 73 watch vessel) and periodic Transient Killer Whale Populations and Ranges # Calves Interval Sighted 5 Monterey Bay. Number of gray whale 0.16 64 Transient Killer Whale Populations and Ranges 5 5 calves and timing of migration 64 57 dedicated boat surveys were 0 5 calves and timing of migration 0.14 57 dedicated boat surveys were & Gray Whale Migration Route (red) 22 1 2 80 0 0 4 8 5 9 3 7 5 9 3 7 5 9 3 7 0 d td df & Gray Whale Migration Route (red) 22 1 2 8.0 20 24 28 /1 /5 /9 13 17 21 25 29 /3 /7 11 15 19 23 27 31 0 (clumped dispersed) varied among 0 12 conducted year -round for & Gray Whale Migration Route (red) 22 1 2 8.0 /2 /2 /2 4/ 4/ 4/ /1 /1 /2 /2 /2 5/ 5/ /1 /1 /1 /2 /2 /3 20 25 30 /4 /9 4 9 24 29 /4 /9 4 9 24 29 /3 (clumped, dispersed) varied among 0.12 46 conducted year round for 23 2 1 3/ 3/ 3/ 4 4 4 4/ 4/ 4/ 4/ 4/ 5 5 5/ 5/ 5/ 5/ 5/ 5/ 3/2 3/2 3/3 4/ 4/ 4/1 4/1 4/2 4/2 5/ 5/ 5/1 5/1 5/2 5/2 6/ 01 46 killer whales 23 2 1 --- 3 3 3 4 4 4 4 4 5 5 5 5 5 5 3 3 3 4 4 4 4 5 5 5 5 years. 0.1 35 killer whales. 21 3 3 65 Gulf of Alaska years. Gray Whale 29 30 35 34 21 3 3 65 Gulf of Alaska Gray Whale F di A 0.08 29 30 34 21 3 3 6.5 Transients Feeding Area 20 18 4 2 80 * Transients 0.06 20 22 18 4 2 8.0 * 0.06 22 gray whale Monterey Bay 18 5 2 0 04 17 gray whale Monterey Bay Killer Whale Sightings and Attacks 18 5 1 --- 0.04 13 17 calves occur Killer Whale Sightings and Attacks 18 5 1 --- 13 calves occur Killer Whale Sightings and Attacks 19 6 2 90 (rare) 0.02 C t t d kill hl i hti ddt i ti 19 6 2 9.0 * Kill Wh l P It ( 132) (rare) Concentrated killer whale sightings corresponded to migration 19 6 2 9.0 * Killer Whale Prey Items (n=132) 0 Concentrated killer whale sightings corresponded to migration 17 7 1 90 Killer Whale Prey Items (n=132) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec period for mother/calf gray whales Attacks were most frequent 17 7 1 9.0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec period for mother/calf gray whales. Attacks were most frequent 17 8 2 65 P d i G Wh l i i dl f Sighting Locations of Killer Whales d k f h / lf i i M 17 8 2 65 * Predation on Gray Whales is very conspicuous and lasts for Al k P i l Sighting Locations of Killer Whales around peak of mother/calf migration past Monterey 17 8 2 6.5 * Predation on Gray Whales is very conspicuous and lasts for Alaska Peninsula Sighting Locations of Killer Whales around peak of mother/calf migration past Monterey. 18 9 1 several hours whereas predation on smaller mammals may Alaska Peninsula & Al i T i Mean Group Size (97-0 2004 was exceptional as gray whale calf numbers were high 18 9 1 --- several hours, whereas predation on smaller mammals may West Coast & Aleutian Transients Mean Group Size (97 0 n = total sightings for each month compiled from 97 07 2004 was exceptional as gray whale calf numbers were high, 10 60 West Coast & Aleutian Transients n = total sightings for each month compiled from 97-07 18 10 3 60 occur in several minutes so this may bias our prey proportions T i 12 killer whale sightings were frequent and coincided with the most 18 10 3 6.0 occur in several minutes so this may bias our prey proportions. Transients 73 killer whale sightings were frequent, and coincided with the most 16 11 2 10 Transients d ti t ddi thi td b 16 11 2 10 2 594 k 10 predation events ever recorded since this study began. 16 12 * 2 2,594 km 10 predation events ever recorded since this study began. 14 12 * 2 90 California Sea Lion 64 14 12 2 9.0 California Sea Lion 30 64 14 13 2 90 G Wh l C lf T i P l i 8 30 14 13 2 9.0 Gray Whale Calf Transient Populations 20 22 35 14 13 2 9.0 Gray Whale Calf Transient Populations 20 29 22 57 35 12 14 * 1 Dall’s Porpoise M t B 6 34 17 12 14 * 1 --- Dall’s Porpoise Monterey Bay 6 13 46 34 17 09 15 2 70 145 t i t 13 46 09 15 2 70 Elephant Seal 145 transients gray whale 09 15 2 7.0 Elephant Seal 4 gray whale l H b S l NMML/NOAA map calves occur Harbor Seal Levels of POPs in Monterey Bay Transients NMML/NOAA map Gray Whale Harbor Seal Levels of POPs in Monterey Bay Transients Breeding Area 2 Seabird Levels of POPs in Monterey Bay Transients Breeding Area 2 Seabird P Wh SdD l hi 0 Years between the birth of calves P. Wh-Sd Dolphin Blue bar indicates levels of PCBs and DDTs found in 0 Black dots indicate sighting locations as an example for one killer Years between the birth of calves P. W h Sd Dolphin Blue bar indicates levels of PCBs and DDTs found in Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Black dots indicate sighting locations as an example for one killer f hf l df 6 Common Dolphin hl ih d li i f Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec hl id ifi d i M B d h l i l for each female ranged from 6 to Common Dolphin Monterey Bay whales with red line as a comparison for mean whale core group identified in Monterey Bay and other locations along for each female ranged from 6 to Ri ’Dlhi Monterey Bay whales with red line as a comparison for mean whale core group identified in Monterey Bay and other locations along 10 years over a period of 7 to 21 Risso’s Dolphin l l fS th id t (fi h t ) d Al k id t west coast with Southeast Alaska most likely the extreme limit of range 10 years over a period of 7 to 21 Risso s Dolphin levels of Southern resident (fish-eaters) and Alaska resident west coast with Southeast Alaska most likely the extreme limit of range. H b P i levels of Southern resident (fish eaters) and Alaska resident M ih h d i hi C lif i d BCA k Killer whales were frequently sighted and occurred in the years During this time each Harbor Porpoise killer whales (Samples analyzed by G Ylitalo/NOAA) More re-sights have occurred within California and up to B C Attacks Monterey Killer whales were frequently sighted and occurred in the years. During this time each Harbor Porpoise PCB DDT killer whales (Samples analyzed by G. Ylitalo/NOAA). More re-sights have occurred within California, and up to B.C. Attacks Monterey l t d i i di t th f l hdf 1t 3 ii PCB DDT S l ll tdb ki bi ith i hl td Al ti (C M tki ) ith di largest groups during spring, corresponding to the female had from 1 to 3 surviving PCB DDT Samples collected by skin biopsy with air gun. on gray whales are reported near Aleutians (C. Matkin), with sporadic largest groups during spring, corresponding to the female had from 1 to 3 surviving 30 Samples collected by skin biopsy with air gun. on gray whales are reported near Aleutians (C. Matkin), with sporadic migration period for mother/calf pairs of gray whales calves The * indicates a known 0 10 20 30 40 reports along west coast but occur consistently in Monterey Bay migration period for mother/calf pairs of gray whales. calves. The * indicates a known 0 10 20 30 40 reports along west coast, but occur consistently in Monterey Bay. lf d hf h f l 0 Southern residents Al k id calf death for that female P t Southern residents Alaska residents PCB DDT Kill hl f tl i hti th calf death for that female. Percent Alaska residents PCB DDT Killer whales were frequently sighting near the Percent (threatened pop) DDT Killer whales were frequently sighting near the N mber Of Whales (threatened pop) edge of the canyon (200 400 m depth; 1987 2007) Number Of Whales edge of the canyon (200-400 m depth; 1987-2007). Number Of Whales Si hti F b Y fC G Kill hl ff C lif i i In Each Age Class Sighting Frequency by Year of Core Groups Killer whales off California contain some In Each Age Class Sighting Frequency by Year of Core Groups P d ti G Wh l C lf Killer whales off California contain some In Each Age Class Predation on Gray Whale Calf Si hti F fC G of the highest levels of PCBs and DDTs for D i S i (G Wh l Mi ti P i d) Predation on Gray Whale Calf ng/kg Sighting Frequency of Core Groups of the highest levels of PCBs and DDTs for Age Class # of Whales During Spring (Gray Whale Migration Period) ng/kg Sighting Frequency of Core Groups Age Class # of Whales During Spring (Gray Whale Migration Period) wt any cetacean population High levels are wt Five Core Groups occurred most often and often any cetacean population. High levels are Five Core Groups occurred most often and often lik l d t id l h i l th t th dt th t h t hl likely due to residual chemicals that were d ti f l 27 gathered together to hunt gray whales. likely due to residual chemicals that were reproductive females 27 gathered together to hunt gray whales. 2008 once dumped or drained into the ocean reproductive females 27 2008 once dumped or drained into the ocean 2007 / d i f 11 0 14 bf th b d l 2007 non/post reproductive fem 11 0.14 before they were banned plus some non/post reproductive fem 11 before they were banned, plus some 2006 0 12 atmospheric input from other regions 2006 adult males 23 0.12 atmospheric input from other regions. 2005 adult males 23 2005 01 2005 female type/juv 33 0.1 2004 female type/juv 33 2004 0 08 l 18 0.08 2003 calves 18 2003 calves 18 0 06 0.06 2002 T l 112 2002 Total 112 0 04 2001 Total 112 0.04 2001 0 02 2000 0.02 2000 CONCLUSIONS 0 1999 CONCLUSIONS Core Group Associations 0 A B C D E F G H I J K L M N O P Q R S T U V W 1999 CONCLUSIONS d ti f l ith j / l Core Group Associations A B C D E F G H I J K L M N O P Q R S T U V W 1998 CONCLUSIONS = reproductive female with juvs/calves Core Group Associations Core Groups 1998 reproductive female with juvs/calves 1998 t d ti f l 1997 = post reproductive female 1997 This long-term study provides valuable information on the ecology of killer whales off California: post reproductive female This long-term study provides valuable information on the ecology of killer whales off California: d lt l CA70 < 1978 A B C D E F G H I J K L M N O P Q R S T U V W Di t ib ti Kill hl hi hl itd ith th d f th M t C f = adult male fC G CA70 < 1978 A B C D E F G H I J K L M N O P Q R S T U V W Distribution: Killer whales were highly associated with the edge of the Monterey Canyon, an area of adult male Example of Core Group F Core Group Distribution: Killer whales were highly associated with the edge of the Monterey Canyon, an area of Example of Core Group F Core Group higher productively and prey availability Killer whales ranged from California to Southeast Alaska Example of Core Group F higher productively and prey availability. Killer whales ranged from California to Southeast Alaska. Associations among killer whales are C i f 2 F l Wh l # 70 ith 3 ff i d (70 O Wh l ih d d ih i ifi l ihi ihl i Associations among killer whales are Core groups contain from 2 to Female Whale # 70 with 3 offspring and (70a, = 1 time =2 5 times =6 10 times = 11+ times Occurrence: Whales were sighted year round with significantly more sightings with larger group sizes tdb bl l bl Core groups contain from 2 to Female Whale # 70 with 3 offspring and (70a, = 1 time = 2-5 times = 6-10 times = 11+ times Occurrence: Whales were sighted year round, with significantly more sightings with larger group sizes represented by symbols: larger blue 8 whales that are highly 70b 70c) and calf of 70a includes year born during spring corresponding to the mom/calf gray whale migration a prime prey item represented by symbols: larger blue 8 whales that are highly 70b, 70c) and calf of 70a, includes year born. during spring corresponding to the mom/calf gray whale migration, a prime prey item. circles indicate core groups (groups of i d i ( ) Thi i fi tk lf f 70 (17 ld) P l i ll hl ih d hil ih d l l i h circles indicate core groups (groups of associated over time (years) This is first known calf for 70a (17 years old). Kill hl f l ih dd i h h / lf hl Population: Not all whales are sighted every year while some are sighted regularly suggesting that kill hl ih hi h ffi i f associated over time (years). This is first known calf for 70a (17 years old). Killer whales are most frequently sighted during the mother/calf gray whale Population: Not all whales are sighted every year, while some are sighted regularly suggesting that killer whales with a high coefficient of S These whales are always sighted together Killer whales are most frequently sighted during the mother/calf gray whale M t B i t lh f hl d th i ll D i th killer whales with a high coefficient of Some core groups are more These whales are always sighted together. migration period At this time core groups of whales gather together to hunt gray Monterey Bay is a central home range for some whales and others occasionally occur. During the gray association > 8) and smaller circles Some core groups are more migration period. At this time, core groups of whales gather together to hunt gray Monterey Bay is a central home range for some whales and others occasionally occur. During the gray association > .8) and smaller circles frequently sighted than others hl i 5 hl f ih d lil i whale season the greatest number of individual whales are sighted suggesting that whales that frequent frequently sighted than others 0 1992 70b 1998 whales in groups up to 25 whales Core groups are often sighted multiple times whale season, the greatest number of individual whales are sighted suggesting that whales that frequent indicate sex class All reproductive d ll h d 70a 1992 70b 1998 70c 2003 whales in groups up to 25 whales. Core groups are often sighted multiple times th t th B t h t hl l indicate sex class. All reproductive and all groups have occurred 70a 1992 70b 1998 70c 2003 th h t th i id h d ti i t i lti l hl other areas come to the Bay to hunt gray whale calves. f l h l /j il and all groups have occurred throughout the spring period each year and participate in multiple gray whale other areas come to the Bay to hunt gray whale calves. females have one or more calves/juveniles during spring months throughout the spring period each year and participate in multiple gray whale Predation: Transient killer whales sighted in Monterey Bay were highly associated with the presence of females have one or more calves/juveniles during spring months attacks within a month’s time suggesting the whales may be binge feeding Predation: Transient killer whales sighted in Monterey Bay were highly associated with the presence of associated with them in their core group di hl attacks within a month s time, suggesting the whales may be binge feeding. hl l d h k ld fh il d l f l hibi i associated with them in their core group. corresponding to gray whale gray whale calves and must have knowledge of the spatial and temporal patterns of calves; exhibiting J il d l d corresponding to gray whale gray whale calves and must have knowledge of the spatial and temporal patterns of calves; exhibiting Juveniles and calves are not represented migration although not all core characteristics of cultural transmission Juveniles and calves are not represented. migration, although not all core characteristics of cultural transmission. Lines between circles represent linkages Lines between circles represent linkages groups are sighted each year Association: Core groups include one or more females with their offspring from 2 to 8 whales with h h b groups are sighted each year. Association: Core groups include one or more females with their offspring, from 2 to 8 whales with among groups; groups that have been hi h ffi i t f i ti Th ll ft i ht d th i bt i ith th among groups; groups that have been P d i high coefficients of associations. These small groups are often sighted on their own but mix with other i ht dt th Predation on high coefficients of associations. These small groups are often sighted on their own but mix with other sighted together. Predation on groups periodically especially when cooperatively hunting gray whale calves during spring sighted together. i l hi 70 1 2007 groups periodically especially when cooperatively hunting gray whale calves during spring. Risso’s Dolphin 70a-1 2007 CA 0’ if l C t i t Th hl h hi h i f POP’ hi h ld ib hil Risso s Dolphin 70a 1 2007 CA70’s group is frequently Contaminants: These whales have high concentrations of POP’s which could contribute to their low CA70 s group is frequently Contaminants: These whales have high concentrations of POP s which could contribute to their low All transients in this population are linked by associations such as in any given sighting several core groups may be together i ht d d CA70 h b reproductive rate All transients in this population are linked by associations, such as in any given sighting, several core groups may be together sighted and CA70 has been reproductive rate. dd i h ihi fh b i d ih diff f i ihi C sighted and CA70 has been and during another sighting one of these groups may be associated with a different group from previous sighting Core groups involved in many gray whale and during another sighting one of these groups may be associated with a different group from previous sighting. Core groups involved in many gray whale ith j t f l l i ld th i ff i F l ith ll l fi il ft t lt th f tt k tl t 17 with just one female also include their younger offspring. Females with small calves of similar age often travel together for attacks over at least 17 years. with just one female also include their younger offspring. Females with small calves of similar age often travel together for attacks over at least 17 years. periods of time often several years Female/offspring core groups will gather together during cooperative hunts for gray whales B W tt periods of time, often several years. Female/offspring core groups will gather together during cooperative hunts for gray whales. B. Watts

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Page 1: El fM lEcology of Mammalgy -H i (“T i ”) Kill Wh lH ti (“T ... · SocialandMatingamongCoreGroupsSocial and Mating among Core Groupsgg pEl fM lEcology of Mammalgy -H i (“T

Social and Mating among Core Groups E l f M l H i (“T i ”) Kill Wh lSocial and Mating among Core Groups E l f M l H ti (“T i t”) Kill Wh lg g p Ecology of Mammal Hunting (“Transient”) Killer WhalesEcology of Mammal Hunting (“Transient”) Killer WhalesEcology of Mammal-Hunting ( Transient ) Killer WhalesEcology of Mammal-Hunting ( Transient ) Killer WhalesEcology of Mammal Hunting ( Transient ) Killer WhalesEcology of Mammal Hunting ( Transient ) Killer Whales gy g ( )gy gi C if i A 22 Si M t B C lif i A 22 Y St din Montere Ba California: A 22 Year St din Monterey Bay California: A 22 Year Studyin Monterey Bay California: A 22-Year Studyin Monterey Bay, California: A 22-Year Studyin Monterey Bay, California: A 22 Year Studyin Monterey Bay, California: A 22 Year Studyy y, yy y, y

N Bl k ( b h l @ l ) Ri h d T ll M B C P j P O B 52001 P ifi G CA 93950Nancy Black (mbaywhale@aol com) Richard Ternullo; Monterey Bay Cetacean Project P O Box 52001 Pacific Grove CA 93950Nancy Black (mbaywhale@aol com) Richard Ternullo; Monterey Bay Cetacean Project P O Box 52001 Pacific Grove CA 93950Nancy Black ([email protected]), Richard Ternullo; Monterey Bay Cetacean Project, P.O. Box 52001, Pacific Grove, CA 93950y ( y @ ), ; y y j , , ,G th f M l Kill Wh l O 16 YGrowth of Male Killer Whales Over 16 Years C f Mi i G Wh l C l (f W P /NMFS)ABSTRACT Growth of Male Killer Whales Over 16 Years Counts of Migrating Gray Whale Calves (from W Perryman/NMFS)ABSTRACT Counts of Migrating Gray Whale Calves (from W. Perryman/NMFS)ABSTRACT Counts of Migrating Gray Whale Calves (from W. Perryman/NMFS)

Since 1987 we photo identified whales recorded location prey type behaviors and collected 01 0292 99 06 D (b h) O l d b Kill Wh l Si hti D t ( d)Since 1987 we photo-identified whales, recorded location, prey type, behaviors and collected 01 0292 99 06 per Day (bar graph) Over layed by Killer Whale Sighting Dates (red)p , , p y yp ,bi l d b d i l i l i l

092 99 06 per Day (bar graph) Over-layed by Killer Whale Sighting Dates (red)biopsy samples on year-round boat surveys to determine population parameters ecological

per Day (bar graph) Over layed by Killer Whale Sighting Dates (red) biopsy samples on year-round boat surveys to determine population parameters, ecological

d Att k D t (bl ) b Y ( l t l )tt d t i t l l f kill h l T i t i ht d 545 d d and Attack Dates (blue) by Year (select examples)patterns, and contaminant levels of killer whales. Transients were sighted on 545 days, and and Attack Dates (blue) by Year (select examples) patterns, and contaminant levels of killer whales. Transients were sighted on 545 days, and ( ) y ( p )154 individuals were identified (from 1 to 80 times each) over 20 years with a current • L d154 individuals were identified (from 1 to 80 times each) over 20 years with a current • Legend:y

l ti f 112 h l (22% d ti f l 11% t d ti f l 20% 2005 (calf count=345)2005 ( lf t 345)Legend:2001 (calf count = 87)

2001 ( lf t 87)population of 112 whales (22% reproductive females, 11% post reproductive females, 20% OX2005 (calf count=345)2005 (calf count=345) Bars number of calves/day

( )2001 (calf count=87)population of 112 whales (22% reproductive females, 11% post reproductive females, 20% X2005 (calf count=345) Bars = number of calves/day2001 (calf count=87)

adult males) Whales frequented the canyon edge in Monterey Bay and were re sighted from 45y

45adult males). Whales frequented the canyon edge in Monterey Bay and were re-sighted from 45) q y g y y gh C lif i S h Al k Th l i i d f i d 40 = killer whale sightings40southern California to Southeast Alaska The population consisted of core groups comprised 40 = killer whale sightings, 40southern California to Southeast Alaska. The population consisted of core groups comprised

X X X X OOX size of oval relative to35of 1 3 adult females and their offspring Calving interval ranged from 5 to 10 years These 35 X X X X X

OOX size of oval relative to 35 Xof 1-3 adult females and their offspring. Calving interval ranged from 5 to 10 years. These i (5 10 15 20 25)p g g g y00 0292 94 96 08 30 group size (5, 10,15, 20, 25)30

whales (n=9) were highly contaminated with POPs which could contribute to a low 00 0292 94 96 08 30 group size (5, 10,15, 20, 25)whales (n=9) were highly contaminated with POPs, which could contribute to a low 0294 96 08

25 25

d ti t d hi h t lit l l M l ∑PCB 87 888 /25

predation events by killer25

reproductive rate and higher mortality level. Mean values were ∑PCBs: 87,888ng/g; 20= predation events by killer 20reproductive rate and higher mortality level. Mean values were ∑PCBs: 87,888ng/g; 20

p yh l h l l

20

∑DDTs: 507 148; ∑PBDEs: 15 000 which is among the highest levels recorded for whales on gray whale calves15∑DDTs: 507,148; ∑PBDEs: 15,000 which is among the highest levels recorded for 15whales on gray whale calves15∑ ∑ g g

K h (2007) d l d l ( 4) ∑PCB 630 000 ∑DDT (X in center is attack)cetaceans Krahn (2007) reported on our sampled males (n=4); ∑PCBs: 630 000; ∑DDTs: F Gohier 10(X in center is attack)10cetaceans. Krahn (2007) reported on our sampled males (n=4); ∑PCBs: 630,000; ∑DDTs: F. Gohier 10(O in center is escape)

10

3 700 000; ∑PBDEs: 12 600 We observed 123 predation events on nine species of 5(O in center is escape)53,700,000; ∑PBDEs: 12,600. We observed 123 predation events on nine species of 5( p )5, , ; ∑ , p p

l Wh l d d b f i h l i 0 0mammals Whales occurred year-round but were most frequent with largest group sizes 0 0mammals. Whales occurred year-round but were most frequent with largest group sizes S d A M B 2

0

23

26

29 /1 /4 /7 10

13

16

19

22

25

28 /1 /4 /7 10

13

16

19

22

25

28

31 /3 /6 0 5 0 4 9 4 9 4 9 4 9 4 9 4 9 3

( 12) i d i i di t th i ti f th / lf Study Area: Monterey Bay /2 /2 /2 /2 4/

4/

4/

/1 /1 /1 /1 /2 /2 /2 5/

5/

5/

/1 /1 /1 /1 /2 /2 /2 /3 6/

6/

G Wh l/20

/25

/30

4/4

4/9

/14

/19

/24

/29

5/4

5/9

/14

/19

/24

/29

6/3

(mean=12) occurring during spring, corresponding to the migration of mother/calf gray Study Area: Monterey Bay 3/

3/

3/

3/

4/

4/

4/

4/

4/

4/

4/

5/

5/

5/

5/

5/

5/

5/

5/ Gray Whale3/ 3/ 3/ 4 4 4/ 4/ 4/ 4/ 5/ 5/ 5/ 5/( ea ) occu g du g sp g, co espo d g to t e g at o o ot e /ca g ay Study Area: Monterey Bay

2004 (calf count = 559 1998 ( lf t 440)Gray Whale

whales Fifty four predation events on gray whale calves were recorded 1 to 5 core groups A d S b i C N b f S i i C l2004 (calf count = 559 1998 (calf count = 440)2004 ( lf t 650)

ywhales. Fifty-four predation events on gray whale calves were recorded, 1 to 5 core groups And Submarine Canyon Percent Number of Sightings Number of Surviving Calves 2004 (calf count=650) M th /C lf Mi tiy p g y g p

i l d j t 2 3 f l t ti i th tt k d h l kill d d And Submarine Canyon Percent Number of Sightings Number of Surviving Calves, 45 X45

2004 (calf count=650) Mother/Calf Migration1998 (calf count=440)were involved, just 2-3 females were most active in the attack, and some whales killed and d Sub a e Ca yo Percent Number of Sightings Number of Surviving Calves, 45XO O X X X X X X XO X X O

45 Mother/Calf Migration 1998 (calf count=440)were involved, just 2 3 females were most active in the attack, and some whales killed and g gC l i I t l d N b 40

XO O X X X X X XO X X Og

G h l l d bfed on 6 gray whales over 21 days The number of attacks (0 11/yr) corresponded to the and Mean Group Size of Killer Calving Interval and Number 40 40 X Gray whale calves were counted byfed on 6 gray whales over 21 days. The number of attacks (0-11/yr) corresponded to the and Mean Group Size of Killer Calving Interval, and Number 35X Gray whale calves were counted by g y y ( y ) p

b f h l l b h (87 559 W P /NMFS) C l land Mean Group Size of Killer C g , N 35 35 O XX W P ’ (NMFS)number of gray whale calves born each year (87 to 559; per W Perryman/NMFS) Cultural

p(199 200 ) f Si hti Y F F l 30

35 OX Wayne Perryman’s group (NMFS) number of gray whale calves born each year (87 to 559; per W. Perryman/NMFS). Cultural Whales by Month (1997 2007) of Sighting Years For Females 30 30Wayne Perryman s group (NMFS)

transmission of spatial/temporal timing is evident and the bathymetric features of the canyon Whales by Month (1997-2007) of Sighting Years For Females25

30 from Pt Piedras Blancas (64 km southtransmission of spatial/temporal timing is evident and the bathymetric features of the canyon Whales by Month (1997 2007) g g25 25

from Pt. Piedras Blancas (64 km south p p g y y20

25

f M t ) Kill h l i htiappear advantageous to foraging killer whales 2020 of Monterey). Killer whale sightingsappear advantageous to foraging killer whales.

Percent Number Sightings Per Month (9_

1520 of Monterey). Killer whale sightings

Percent Number Sightings Per Month (9• D il i i ( h l Whale Surviving X Calving # Years 15 and attacks were documented in• Daily opportunistic (whale Whale Surviving X Calving # Years 1515 and attacks were documented in

0 18Daily opportunistic (whale g g

10 M B N b f h l0.18

73watch vessel) and periodicT i t Kill Wh l P l ti d R # Calves Interval Sighted10

10 Monterey Bay Number of gray whale0 16

73watch vessel) and periodic Transient Killer Whale Populations and Ranges # Calves Interval Sighted 5Monterey Bay. Number of gray whale

0.16 64) pTransient Killer Whale Populations and Ranges g 5

5 calves and timing of migration6457dedicated boat surveys were

p g0

5 calves and timing of migration 0.14 57dedicated boat surveys were & Gray Whale Migration Route (red) 221 2 8 0

0

0 4 8 5 9 3 7 5 9 3 7 5 9 3 7 0g g

d t d d f& Gray Whale Migration Route (red) 221 2 8.0 20

24

28 /1 /5 /9 13

17

21

25

29 /3 /7 11

15

19

23

27

31 0 (clumped dispersed) varied among

0 12conducted year-round for& Gray Whale Migration Route (red) 221 2 8.0

/2 /2 /2 4/

4/

4/

/1 /1 /2 /2 /2 5/

5/

/1 /1 /1 /2 /2 /3 20 25 30 /4 /9 4 9 24 29 /4 /9 4 9 24 29 /3 (clumped, dispersed) varied among 0.12

46conducted year round for y g

232 1 3/

3/

3/ 4 4 4

4/

4/

4/

4/

4/ 5 5

5/

5/

5/

5/

5/

5/

3/2

3/2

3/3 4/ 4/

4/1

4/1

4/2

4/2 5/ 5/

5/1

5/1

5/2

5/2 6/

0 146killer whales 232 1 --- 3 3 3 4 4 4 4 4 5 5 5 5 5 5 3 3 3 4 4 4 4 5 5 5 5 years.0.1

35killer whales.213 3 6 5Gulf of Alaska

years.Gray Whale 29 30

35 34 213 3 6 5Gulf of AlaskaGray WhaleF di A

0.08 29 30 34 213 3 6.5TransientsFeeding Area20 184 2 8 0*

Transientsg0.06 20 22 184 2 8.0*0.06 22gray whaleMonterey Bay 18

52

0 04 17gray whaleMonterey Bay Killer Whale Sightings and Attacks185 1 ---0.04

13 17calves occury y Killer Whale Sightings and Attacks185 1 ---

13calves occur Killer Whale Sightings and Attacks196 2 9 0(rare) 0.02

g g• C t t d kill h l i hti d d t i ti196 2 9.0* Kill Wh l P It ( 132)(rare) • Concentrated killer whale sightings corresponded to migration196 2 9.0* Killer Whale Prey Items (n=132)0

Concentrated killer whale sightings corresponded to migration 177 1 9 0 Killer Whale Prey Items (n=132)

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec period for mother/calf gray whales Attacks were most frequent177 1 9.0 y ( )Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec period for mother/calf gray whales. Attacks were most frequent

178 2 6 5 • P d i G Wh l i i d l fSighting Locations of Killer Whalesp g y q

d k f h / lf i i M178 2 6 5* • Predation on Gray Whales is very conspicuous and lasts forAl k P i l Sighting Locations of Killer Whales around peak of mother/calf migration past Monterey178 2 6.5* Predation on Gray Whales is very conspicuous and lasts for Alaska Peninsula Sighting Locations of Killer Whales around peak of mother/calf migration past Monterey.

189 1 several hours whereas predation on smaller mammals mayAlaska Peninsula& Al i T i Mean Group Size (97-0 • 2004 was exceptional as gray whale calf numbers were high189 1 --- several hours, whereas predation on smaller mammals may

West Coast& Aleutian Transients Mean Group Size (97 0n = total sightings for each month compiled from 97 07 • 2004 was exceptional as gray whale calf numbers were high, 10 6 0

, p yWest Coast& Aleutian Transients n = total sightings for each month compiled from 97-07 p g y g ,

1810 3 6 0 occur in several minutes so this may bias our prey proportionsT i 12 killer whale sightings were frequent and coincided with the most1810 3 6.0 occur in several minutes so this may bias our prey proportions.Transients 73 killer whale sightings were frequent, and coincided with the most

1611 2 10Transients 3

d ti t d d i thi t d b1611 2 102 594 k 10 predation events ever recorded since this study began.16

12 *2 0

2,594 km 10 predation events ever recorded since this study began. 1412 * 2 9 0 California Sea Lion,

641412 2 9.0 California Sea Lion

3064

1413 2 9 0 G Wh l C lfT i P l i8 30 1413 2 9.0 Gray Whale CalfTransient Populations 20 22 35

1413 2 9.0 Gray Whale CalfTransient Populations 2029

2257

351214 * 1 Dall’s PorpoiseM t B 6

9 534 17 1214 * 1 --- Dall’s PorpoiseMonterey Bay 6

13 4634 17

0915 2 7 0py y

145 t i t 13 46 0915 2 7 0 Elephant Seal145 transients gray whale 0915 2 7.0 Elephant Sealt a s e ts4

gray whalel H b S lNMML/NOAA map calves occur Harbor SealLevels of POPs in Monterey Bay TransientsNMML/NOAA map Gray Whale Harbor SealLevels of POPs in Monterey Bay Transientsy

Breeding Area 2 SeabirdLevels of POPs in Monterey Bay TransientsBreeding Area 2 Seabirdy y

P Wh Sd D l hi0 •Years between the birth of calves P. Wh-Sd Dolphin• Blue bar indicates levels of PCBs and DDTs found in0• Black dots indicate sighting locations as an example for one killer •Years between the birth of calves P. Wh Sd Dolphin• Blue bar indicates levels of PCBs and DDTs found in Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec• Black dots indicate sighting locations as an example for one killer

f h f l d f 6 Common Dolphinh l i h d li i fJan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Decg g p

h l id ifi d i M B d h l i l for each female ranged from 6 to Common DolphinMonterey Bay whales with red line as a comparison for meanwhale core group identified in Monterey Bay and other locations along for each female ranged from 6 to pRi ’ D l hi

Monterey Bay whales with red line as a comparison for mean whale core group identified in Monterey Bay and other locations along 10 years over a period of 7 to 21 Risso’s Dolphinl l f S th id t (fi h t ) d Al k id twest coast with Southeast Alaska most likely the extreme limit of range 10 years over a period of 7 to 21 Risso s Dolphinlevels of Southern resident (fish-eaters) and Alaska residentwest coast with Southeast Alaska most likely the extreme limit of range. y p

H b P ilevels of Southern resident (fish eaters) and Alaska resident y g

M i h h d i hi C lif i d B C A k • Killer whales were frequently sighted and occurred in the years During this time each Harbor Porpoisekiller whales (Samples analyzed by G Ylitalo/NOAA)More re-sights have occurred within California and up to B C Attacks Monterey Killer whales were frequently sighted and occurred in the years. During this time each Harbor PorpoisePCB DDTkiller whales (Samples analyzed by G. Ylitalo/NOAA). More re-sights have occurred within California, and up to B.C. Attacks Monterey l t d i i di t th f l h d f 1 t 3 i i PCB DDTp y y

S l ll t d b ki bi ith ih l t d Al ti (C M tki ) ith diy largest groups during spring, corresponding to the female had from 1 to 3 surviving PCB DDTSamples collected by skin biopsy with air gun.on gray whales are reported near Aleutians (C. Matkin), with sporadic largest groups during spring, corresponding to the female had from 1 to 3 surviving

30Samples collected by skin biopsy with air gun.on gray whales are reported near Aleutians (C. Matkin), with sporadic

migration period for mother/calf pairs of gray whales calves The * indicates a known 0 10 20 30 40reports along west coast but occur consistently in Monterey Bay migration period for mother/calf pairs of gray whales. calves. The * indicates a known 0 10 20 30 40reports along west coast, but occur consistently in Monterey Bay. g p p g ylf d h f h f l

0Southern residents Al k id

p g y y ycalf death for that female P tSouthern residents Alaska residentsPCB DDT• Kill h l f tl i hti thcalf death for that female. PercentAlaska residents PCB DDT• Killer whales were frequently sighting near the Percent(threatened pop) DDTKiller whales were frequently sighting near the

N mber Of Whales (threatened pop)edge of the canyon (200 400 m depth; 1987 2007) Number Of Whales p pedge of the canyon (200-400 m depth; 1987-2007). Number Of Whales g y ( p ; )

Si hti F b Y f C G • Kill h l ff C lif i iIn Each Age ClassSighting Frequency by Year of Core Groups • Killer whales off California contain someIn Each Age ClassSighting Frequency by Year of Core Groups P d ti G Wh l C lfKiller whales off California contain some In Each Age Classg g q y y p Predation on Gray Whale CalfSi hti F f C G of the highest levels of PCBs and DDTs forg

D i S i (G Wh l Mi ti P i d)Predation on Gray Whale Calfng/kgSighting Frequency of Core Groups of the highest levels of PCBs and DDTs for Age Class # of WhalesDuring Spring (Gray Whale Migration Period) ng/kgSighting Frequency of Core Groups gAge Class # of WhalesDuring Spring (Gray Whale Migration Period) wt

g g q y p• any cetacean population High levels are

gg p g ( y g ) wt• Five Core Groups occurred most often and often any cetacean population. High levels are Five Core Groups occurred most often and often lik l d t id l h i l th tth d t th t h t h l likely due to residual chemicals that wered ti f l 27gathered together to hunt gray whales. likely due to residual chemicals that were reproductive females 27gathered together to hunt gray whales.

2008 once dumped or drained into the oceanreproductive females 272008 once dumped or drained into the ocean 2007

p/ d i f 110 14

pb f th b d l2007 non/post reproductive fem 110.14

before they were banned plus somenon/post reproductive fem 11 before they were banned, plus some 2006

p p0 12

atmospheric input from other regions2006 adult males 230.12

atmospheric input from other regions.2005

adult males 23 p p g2005 0 12005 female type/juv 330.1

2004 female type/juv 332004 yp j0 08

l 180.08

2003 calves 182003 calves 180 060.06

2002 T l 1122002 Total 1120 04

2001Total 1120.04

20010 022000 0.022000

CONCLUSIONS01999 CONCLUSIONSCore Group Associations0

A B C D E F G H I J K L M N O P Q R S T U V W1999 CONCLUSIONSd ti f l ith j / l Core Group AssociationsA B C D E F G H I J K L M N O P Q R S T U V W

1998CONCLUSIONS= reproductive female with juvs/calves Core Group AssociationsCore Groups

1998 reproductive female with juvs/calves pp

1998t d ti f l1997 = post reproductive female1997 This long-term study provides valuable information on the ecology of killer whales off California: post reproductive female This long-term study provides valuable information on the ecology of killer whales off California:

d lt lCA70 < 1978A B C D E F G H I J K L M N O P Q R S T U V W

g y p gy• Di t ib ti Kill h l hi hl i t d ith th d f th M t C f= adult malef C G

CA70 < 1978A B C D E F G H I J K L M N O P Q R S T U V W • Distribution: Killer whales were highly associated with the edge of the Monterey Canyon, an area of adult maleExample of Core Group FCore Group

Distribution: Killer whales were highly associated with the edge of the Monterey Canyon, an area of Example of Core Group FCore Group higher productively and prey availability Killer whales ranged from California to Southeast AlaskaExample of Core Group F

higher productively and prey availability. Killer whales ranged from California to Southeast Alaska.• Associations among killer whales are• C i f 2F l Wh l # 70 ith 3 ff i d (70 g p y p y y g• O Wh l i h d d i h i ifi l i h i i h l i

• Associations among killer whales are • Core groups contain from 2 toFemale Whale # 70 with 3 offspring and (70a,= 1 time = 2 5 times = 6 10 times = 11+ times • Occurrence: Whales were sighted year round with significantly more sightings with larger group sizes

gt d b b l l bl

Core groups contain from 2 to Female Whale # 70 with 3 offspring and (70a, = 1 time = 2-5 times = 6-10 times = 11+ times Occurrence: Whales were sighted year round, with significantly more sightings with larger group sizes represented by symbols: larger blue8 whales that are highly70b 70c) and calf of 70a includes year born during spring corresponding to the mom/calf gray whale migration a prime prey item

represented by symbols: larger blue 8 whales that are highly 70b, 70c) and calf of 70a, includes year born. during spring corresponding to the mom/calf gray whale migration, a prime prey item.circles indicate core groups (groups ofg y

i d i ( )y

Thi i fi t k lf f 70 (17 ld) g p g p g g y g , p p y• P l i ll h l i h d hil i h d l l i h

circles indicate core groups (groups of associated over time (years)This is first known calf for 70a (17 years old).• Kill h l f l i h d d i h h / lf h l • Population: Not all whales are sighted every year while some are sighted regularly suggesting that

g p (g pkill h l i h hi h ffi i f

associated over time (years). This is first known calf for 70a (17 years old). • Killer whales are most frequently sighted during the mother/calf gray whale Population: Not all whales are sighted every year, while some are sighted regularly suggesting that killer whales with a high coefficient ofSThese whales are always sighted togetherKiller whales are most frequently sighted during the mother/calf gray whale

M t B i t l h f h l d th i ll D i thkiller whales with a high coefficient of Some core groups are moreThese whales are always sighted together.

migration period At this time core groups of whales gather together to hunt gray Monterey Bay is a central home range for some whales and others occasionally occur. During the grayassociation > 8) and smaller circlesSome core groups are more y g g

migration period. At this time, core groups of whales gather together to hunt gray Monterey Bay is a central home range for some whales and others occasionally occur. During the gray association > .8) and smaller circles frequently sighted than othersg p , g p g g g yh l i 5 h l f i h d l i l i whale season the greatest number of individual whales are sighted suggesting that whales that frequent

)frequently sighted than others 0 1992 70b 1998whales in groups up to 25 whales Core groups are often sighted multiple times whale season, the greatest number of individual whales are sighted suggesting that whales that frequent indicate sex class All reproductive

q y gd ll h d70a 1992 70b 1998 70c 2003whales in groups up to 25 whales. Core groups are often sighted multiple times g g gg g q

th t th B t h t h l lindicate sex class. All reproductive and all groups have occurred70a 1992 70b 1998 70c 2003

th h t th i i d h d ti i t i lti l h l other areas come to the Bay to hunt gray whale calves.p

f l h l /j iland all groups have occurred

throughout the spring period each year and participate in multiple gray whale other areas come to the Bay to hunt gray whale calves. females have one or more calves/juvenilesduring spring monthsthroughout the spring period each year and participate in multiple gray whale • Predation: Transient killer whales sighted in Monterey Bay were highly associated with the presence offemales have one or more calves/juveniles during spring months

attacks within a month’s time suggesting the whales may be binge feeding • Predation: Transient killer whales sighted in Monterey Bay were highly associated with the presence of associated with them in their core groupg p g

di h lattacks within a month s time, suggesting the whales may be binge feeding. g y y g y ph l l d h k l d f h i l d l f l hibi i

associated with them in their core group. corresponding to gray whalegg g y g ggray whale calves and must have knowledge of the spatial and temporal patterns of calves; exhibiting

g pJ il d l d

corresponding to gray whale gray whale calves and must have knowledge of the spatial and temporal patterns of calves; exhibiting Juveniles and calves are not representedmigration although not all core characteristics of cultural transmissionJuveniles and calves are not represented. migration, although not all core characteristics of cultural transmission.Lines between circles represent linkages

g , gLines between circles represent linkages groups are sighted each year • Association: Core groups include one or more females with their offspring from 2 to 8 whales with

p gh h b

groups are sighted each year. Association: Core groups include one or more females with their offspring, from 2 to 8 whales with among groups; groups that have beenhi h ffi i t f i ti Th ll ft i ht d th i b t i ith th

among groups; groups that have been P d i high coefficients of associations. These small groups are often sighted on their own but mix with otheri ht d t thPredation on high coefficients of associations. These small groups are often sighted on their own but mix with other sighted together.Predation on

groups periodically especially when cooperatively hunting gray whale calves during springsighted together.

i l hi 70 1 2007 groups periodically especially when cooperatively hunting gray whale calves during spring.Risso’s Dolphin 70a-1 2007 • CA 0’ i f lg p p y p y p y g g y g p g• C t i t Th h l h hi h i f POP’ hi h ld ib h i l

Risso s Dolphin 70a 1 2007 • CA70’s group is frequently • Contaminants: These whales have high concentrations of POP’s which could contribute to their lowp CA70 s group is frequently Contaminants: These whales have high concentrations of POP s which could contribute to their low • All transients in this population are linked by associations such as in any given sighting several core groups may be togetheri ht d d CA70 h b reproductive rate• All transients in this population are linked by associations, such as in any given sighting, several core groups may be together sighted and CA70 has been reproductive rate. p p y , y g g g, g p y g

d d i h i h i f h b i d i h diff f i i h i Csighted and CA70 has been p

and during another sighting one of these groups may be associated with a different group from previous sighting Core groupsinvolved in many gray whale and during another sighting one of these groups may be associated with a different group from previous sighting. Core groupsinvolved in many gray whale ith j t f l l i l d th i ff i F l ith ll l f i il ft t l t th f

y g ytt k t l t 17 with just one female also include their younger offspring. Females with small calves of similar age often travel together forattacks over at least 17 years. with just one female also include their younger offspring. Females with small calves of similar age often travel together for attacks over at least 17 years.

periods of time often several years Female/offspring core groups will gather together during cooperative hunts for gray whalesB W tt periods of time, often several years. Female/offspring core groups will gather together during cooperative hunts for gray whales.B. Watts p y p g g p g g g p g y. Watts