Chapter III — Species of Special Concern 



organizations, universities in the United States, and 

 research institutes in nations party to the former Fur 

 Seal Convention — particularly Japan and Russia. 



In 1995, however, the Service provided $291,000 

 for fur seal research, significantly increasing the 

 species' research budget. As a result, Service scien- 

 tists were able to continue basic population monitoring 

 work and cooperative studies and also to initiate work 

 in several new areas. With regard to ongoing popula- 

 tion monitoring work, the Service conducted counts of 

 adult males at rookeries on the Pribilof Islands, 

 collected and analyzed scat samples to monitor prey 

 utilization, took measurements of pups to assess their 

 condition, and evaluated the accuracy of the methodol- 

 ogy used to estimate population size. 



As noted above, the decline in fur seal numbers 

 has been linked to a decrease in juvenile survival. To 

 help assess factors affecting juvenile survival rates, 

 the Service used some of its 1995 funding to initiate 

 two new lines of study. The first involves investigat- 

 ing the proportion of time pups spend at sea and on 

 land prior to their weaning and departure from the 

 rookeries to begin their one- to three-year period of 

 life at sea. The second area of new work involves 

 developing and constructing lightweight satellite tags 

 suitable for safe use on fur seal pups to determine 

 their at-sea habitat-use patterns. The Service expects 

 to deploy the tags built with this year's funding during 

 the 1996 field season. 



Finally, the Service continued partial funding for 

 cooperative studies. Among the cooperative research 

 projects undertaken in 1995 were investigations of 

 differences in female foraging patterns and rates of 

 milk transfer to pups during the lactation period; an 

 evaluation of the effect of ending the commercial 

 harvest on population growth and demography; 

 genetic studies to assess movement of animals between 

 rookeries in different parts of the species' range; an 

 assessment of the effect of pollutants on the immune 

 response system of fur seal pups; monitoring marine 

 debris entanglement rates among juvenile male fur 

 seals returning to the rookeries after their first few 

 years at sea; and monitoring population trends and 

 mortality at rookeries on the Pribilof Islands for 

 possible impacts associated with discharges from 

 seafood processing plants. 



Pacific Walrus 

 (Odobenus rosmarus divergens) 



The world's largest stock of walruses, and the only 

 stock found in U.S. waters, occurs over continental 

 shelves in the Bering and Chukchi Seas between 

 Alaska and Russia (Figure 3). Numbering more than 

 200,000 animals, this stock represents perhaps 80 to 

 90 percent of the world's walruses. It also is the only 

 stock comprising the Pacific walrus, which is recog- 

 nized as a distinct subspecies. 



Other walrus stocks, which belong to either one or 

 possibly two other subspecies, are located in north- 

 eastern Canada, Greenland, Svalbard and Franz Josef 

 Land in the northern Barents Sea east of Greenland, 

 and northern Russia. The seven or eight stocks in 

 these areas failed to recover from intense commercial 

 hunting that began in the 1500s and continued into the 

 early 1900s. Their current sizes are estimated to 

 range from less than 500 to about 6,000 animals. As 

 recently as the 1700s walruses also reportedly oc- 

 curred in very large numbers in the Gulf of St. 

 Lawrence and as far south as Sable Island, southeast 

 of Nova Scotia, Canada. In both of these areas, 

 however, they were extirpated by commercial hunters 

 and there have been no signs of recolonization. 



Most Pacific walruses migrate seasonally with the 

 advance and retreat of sea ice. When the pack ice 

 reaches its maximum extent between January and 

 March, nearly all walruses are in the Bering Sea, 

 principally south and west of St. Lawrence Island and 

 south and east of Nunivak Island. During the summer 

 months, animals move north with the receding pack 

 ice and by August most of the reproductive compo- 

 nent of the herd (females and dependent calves) have 

 moved through Bering Strait into the Chukchi Sea 

 between Wrangel Island, Russia, and Barrow, Alaska. 

 However, adult males and some immature males 

 remain year-round in the Bering Sea along the east 

 coast of Russia between the Chukotka and Kamchatka 

 Peninsulas and as far south as Bristol Bay in Alaska. 



The Pacific walrus has experienced at least three 

 cycles of depletion and recovery brought on by 

 episodes of excessive commercial hunting. In the 

 1860s they were hunted intensively for oil and ivory 



43 



