Abundance and distribution of the eastern North Pacific Steller sea lion (Eumetopias jubatus) population

Issue:

Author(s): 
Pitcher, Kenneth W., Peter F. Olesiuk, Robin F. Brown, Mark S. Lowry,. Steven J. Jeffries, John L. Sease, Wayne L. Perryman, Charles E. Stinchcomb, Lloyd F. Lowry
Cover date: 
2007
Pages: 
102–115
Abstract: 

The eastern Steller sea lion (Eumetopias jubatus) population comprises animals that breed along the west coast of North America between California and southeastern Alaska. There are currently 13 major rookeries (>50 pups): five in southeastern Alaska, three in British Columbia, two in Oregon, and three in California. Overall abundance has increased at an average annual rate of 3.1% since the 1970s. These increases can largely be attributed to population recovery from predator-control kills and commercial harvests, and abundance is now probably as high as it has been in the last century. The number of rookeries has remained fairly constant (n=11 to 13) over the past 80 years, but there has been a northward shift in distribution of both rookeries and numbers of animals. Based on the number of pups counted in a population-wide survey in 2002, total pup production was estimated to be about 11,000 (82% in southeastern Alaska and British Columbia), representing a total population size as approximately 46,000−58,000 animals.