Steller sea lions range along the North Pacific Rim from northern Japan to California. Pupping and breeding occur late May to early July throughout their range. Males set up territories on rookeries in late May, females arrive shortly thereafter and give birth to a single pup. They alternate between nursing their pup and feeding trips; most pups are weaned by the end of their first year. The species is not known to migrate, but individuals disperse widely outside of the breeding season, particularly adult males and juveniles. Adult males are up to 3.25 m long and weigh up to 1120 kg; females are considerably smaller at up to 2.9 m and 350 kg. Pups weigh about 23 kg at birth. Two separate stocks of Steller sea lions are recognized within U. S. waters: an eastern and western stock. As a result of a precipitous decline in numbers beginning in the 1970s, the western stock is presently listed as Endangered under the ESA.
Dr. Tom Gelatt explains how NOAA Fisheries scientists are working to
protect and study threatened Steller sea lions.
- Population Decline
- Steller sea lion research coordination, 2007, 2008, 2009, 2010, 2011
- Steller sea lion surveys 2008, 2009, 2010, 2011, 2012,, 2013, 2014, 2015, 2016
- Steller sea lion databases
- Employing Technology for Conservation
- Telemetry Research
- Current Research Projects by the Alaska Ecosystems Program
- Current Research Projects by the California Current Ecosystems Program
- Publications: search AFSC database for Steller Sea Lions
- Posters: search AFSC database for Steller Sea Lions
- Quarterly Reports
- KUHN, C. E., K. CHUMBLEY, D. JOHNSON, and L. FRITZ.
2017. A re-examination of the timing of pupping for Steller sea lions Eumetopias jubatus breeding on two islands in Alaska. Endang. Species Res. 32:213-222. https://doi.org/10.3354/esr00796
- BEKLEMISHEVA, V. R., P. L. PERELMAN, N. A. LEMSKAYA, A. I. KULEMZINA, A. A. PROSKURYAKOVA, V. N. BURKANOV, and A. S. GRAPHODATSKY.
2016. The ancestral carnivore karyotype as substantiated by comparative chromosome painting of three pinnipeds, the walrus, the Steller sea lion and the Baikal seal (Pinnipedia, Carnivora). PLoS One 11(1):15. http://dx.doi.org/10.1371/journal.pone.0147647 Online.
- FRITZ, L., K. SWEENEY, R. TOWELL, and T. GELATT.
2016. Aerial and ship-based surveys of Steller sea lions (Eumetopias jubatus) conducted in Alaska in June-July 2013 through 2015, and an update on the status and trend of the western distinct population segment in Alaska. U.S. Dep. Commer., NOAA Tech. Memo. NMFS-AFSC-321, 72 p. (.pdf, 1.8 MB). Online.
- BECKMEN, K. B., M. J. KEOGH, K. A. BUREK-HUNTINGTON, G. M. YLITALO, B. S. FADELY, and K. W. PITCHER.
2016. Organochlorine contaminant concentrations in multiple tissues of free-ranging Steller sea lions (Eumetopias jubatus) in Alaska. Sci. Tot. Environ. 542:441-452.
- Search the AFSC database for additional Steller Sea Lion publications
- Severe Decline in Abundance on Steller Sea Lion Rookery at Medny Island (Commander Islands), Russia
1.16 MB Online.
- Postpartum Period in the Steller Sea Lions of the Commander Islands: the Connection With Decline in Natality
2.4 MB Online.
- Local Abundance and Movement of Atka Mackerel and Other Steller Sea Lion Prey in the Aleutian Islands
866 KB Online.
- Search the AFSC database for additional Steller Sea Lion posters