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Distribution of Sperm Whales from Soviet Catches in the North Pacific
Yulia V. Ivashchenko, Ph.D. National Marine Mammal Laboratory,
Alaska Fisheries Science Center, NMFS, NOAA 7600 Sand Point Way NE, Seattle, WA 98115, USA
[email protected] www.moscowproject.org
ABSTRACT Data from Soviet whaling (much of it illegal) conducted in the North Pacific (NP) were analyzed to inves=gate the distribu=on of sperm whales, notably for 1963-‐71 (the peak of illegal catches). Formerly secret whaling reports provided details of catch distribu=on and composi=on, involving 53,168 whales (although 5,302 could not be assigned to area). Using two lines of longitude (160°E and 160°W), the Soviets divided the NP into three regions: Eastern Region (ER), Central Region (CR) and Kurils (including northern Japan). Catches were 20,652 (ER), 15,335 (CR), and 6,581 (Kurils). Other catches included the Aleu=ans (1,864) and Commander Islands (2,119), pelagic Bering Sea (586), Oleutorskiy Bay (207) and other parts of the pelagic NP (522). Four main areas of catch concentra=on are evident: a large pelagic area (30-‐50°N) in the ER, including the Gulf of Alaska and western coast of North America; the northeastern and southwestern por=ons of the CR; and the southern Kurils/northern Japan. Some of the distribu=on was similar to the geographically more limited 19th century catches plo_ed by Townsend, with a notable concentra=on in the “Japan Ground” in the western Pacific. Where known, sex ra=o was distributed as follows: ER 12,759 females, 6,552 males; CR 8,857 females, 5,435 males; Kurils 4,139 females, 2,354 males; Aleu=ans 55 females, 295 males. The Bering Sea catch had only 1 female and 442 males, but there were a surprising number of females caught in the higher-‐la=tude areas of Oleutorskiy Bay (32, versus 34 males) and the Commander Islands (509, versus 300 males). Reproduc=ve status of mature females in the three main areas (ER, CR and Kurils) was generally similar: pregnant 10.9-‐51.1% (mean 35.3%), res=ng 13.6-‐77.8% (mean 44.5%), lacta=ng 5.4-‐45.5% (mean 20.6%). Overall more than 92,000 sperm whales were killed in 9 years, represen=ng 58% of the total catch over a 30-‐year period. The majority of females were killed during the 6-‐year period 1965-‐71; this mainly illegal removal of a large por=on of the reproduc=vely ac=ve popula=on was reflected in an obvious decline in catches in the ER by 1969, followed by in the CR and Kurils. (Funded by NPRB).
INTRODUCTION !• The USSR conducted extensive illegal whaling worldwide from 1948 to 1979 (Clapham & Ivashchenko 2009, Ivashchenko et al. 2011).
• In the North Pacific, sperm whales were the principal target, with >159,000 taken. Catch data submi_ed to IWC were falsified, both in terms of numbers and sex/size composi=on of the catch.
• This study was conducted to correct the catch record and to examine the distribu=on of North Pacific sperm whales in the Soviet catch.
METHODS !• All data from this study were obtained from formerly secret whaling industry reports found in Russian public archives. These included scien=fic, produc=on and whaling inspectors’ reports. Where necessary, clarifica=ons were obtained through interviews with former Soviet biologists and whalers.
• Data included catch loca=on and some=mes sex, length and matura=onal status.
• Catches were georeferenced and plo_ed using GIS sojware. !
ACKNOWLEDGMENTS !This is Project Number 1209 funded by the North Pacific Research Board. I thank Cherry Allison, Bob Brownell, Phil Clapham, Grigori Derviz, Nikolai Doroshenko, Sarah Mesnick, Randy Reeves, Barbara Taylor and Alex Zerbini for their input to this study. This study is part of the Memoirs Of Soviet Catches Of Whales (MOSCOW) project: www.moscowproject.org.
Figure 2. Soviet sperm whale catches (total and by sex, where known) during the peak period, 1963-71.!
PRINCIPAL RESULTS!• More than 92,000 sperm whales were killed in the peak of illegal whaling, 1963-‐71 (Figure 2); this represented 58% of the total catch over a 30-‐year period.
• There were four major areas of catches (Figure 3): a large pelagic area (30-‐50°N) in the Eastern Region; the northeastern and southwestern por=ons of the Central Region; and the southern Kurils/northern Japan.
• Distribu=on was similar to the geographically more limited 19th century catches plo_ed by Townsend (1935), notably a concentra=on in the “Japan Ground” in the central/western Pacific (Figure 4).
• Sex ra=o by area (Figure 5): a surprising number of females were caught in some higher-‐la=tude areas, notably Oleutorskiy Bay, and in the Commander Islands/western Aleu=ans.
• Most females were killed during 1965-‐71, represen=ng removal of a large por=on of the mature popula=on.
• As part of this study, the IWC catch record was corrected for all species of whales taken by the USSR in the North Pacific between 1948 and 1979 (Ivashchenko et al. 2013).
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2,000
4,000
6,000
8,000
10,000
12,000
14,000
16,000
1963 1964 1965 1966 1967 1968 1969 1970 1971
Total all Sov fleets
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M
LITERATURE CITED!Clapham, P. & Ivashchenko, Y. 2009. A whale of a decep=on. Marine Fisheries Review 71: 44-‐52. Ivashchenko, Y.V., Brownell, R.L. Jr. and Clapham, P.J. 2013. Soviet whaling in the North Pacific: revised catch totals based upon true data. Journal of Cetacean Research and Management 13: 59-‐71. Ivashchenko, Y.V., Clapham, P.J. & Brownell, R.L. Jr. 2011. Soviet illegal whaling: the Devil and the details. Marine Fisheries Review 73: 1-‐19. Townsend C.H. 1935. The distribu=on of certain whales as shown by logbook records of American whaleships. Zoologica NY 19:1-‐50.
Figure 1. Tracks of Soviet factory fleets, 1964-71. Track data were not available for all fleets/years.!
Figure 3. Soviet sperm whale catches, 1948-79. Colored blocks represent whaling areas defined by the USSR.!
Figure 4. Sperm whale catches by 19th century Yankee whalers plotted by Townsend (1935).!
Japan Ground
Soviet catcher vessel and dead sperm whales!
Figure 5. Catch composition for major areas of concentration.!
Number of sperm whales
The recommenda=ons and general content presented in this poster do not necessarily represent the views or official posi=on of the Department of Commerce, the Na=onal Oceanic and Atmospheric Administra=on, or the Na=onal Marine Fisheries Service.