Fur Seal Investigations, 1999

摘要

Researchers from the National Marine Mammal Laboratory conduct fieldinvestigations on the population status of northern fur seals (Callorhinus ursinus) annually on the Pribilof Islands and on Bogoslof Island in the eastern Bering Sea and on San Miguel Island located off the coast of California. The size of the Pribilof stock of northern fur seals in 1998 was estimated to be 973,000 individuals and the total population of fur seals in U.S. rookeries was estimated to be 1,004,000 individuals. Population parameters monitored in 1999 on the Pribilof Islands included the size of the subsistence harvest and the number of adult male fur seals on both islands. A total of 3,801 harem and 7,589 idle adult male seals were counted on St. Paul Island and 1,052 harem and 916 idle adult males were counted on St. George Island. The general decrease in the count of adult males on the Pribilof Islands noted in recent years continued in 1999. The count of territorial males with females (Class 3) on St. Paul Island has declined at a rate of about 3% per year for the last 6 years. The decline between 1998 and 1999 exceeds previous declines, being about 20% for Class 3 males on St. Paul and 17% for Class 3 males on St. George.