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    Steller sea lion haulout surveys

    Steller sea lions at Northeast Point on St. Paul Island.

    The Steller sea lion (SSL) population on the Pribilof Islands has declined to extremely low levels and the sole remaining breeding rookery at Walrus Island is currently in danger of extinction.  Within recorded history SSLs were abundant in the Bering Sea and bred in large numbers on the Pribilof Islands.  Elliott (1880) reported that approximately 10,000 to 12,000 animals were distributed at breeding rookeries on both St. Paul and St. George Islands in the 1870s.  The breeding rookeries on St. Paul and St. George Islands were largely extirpated by 1916 due to a combination of hunting and culling (Loughlin et al. 1984).  Over the last 50 years pup production on Walrus Island has declined by over 90 percent, from 2,866 in 1960 to only 29 pups born in 2005.  Similar to the decline of the Western Alaska SSL population as a whole, the cause of the SSL decline on the Pribilof Islands in recent decades remains unexplained.  The highest ranked threats to the recovery of the Western Alaska SSL population, listed in the Steller Sea Lion Recovery Plan, are environmental variability, competition with fisheries, killer whale predation, and toxic substances (NMFS 2008).

    Steller sea lions hauled out on Sea Lion Rock offshore of Reef Point on St. Paul Island Alaska on June 12, 2012. (BeringWatch Observation GeoXH-5103)

    To help determine the cause of the Steller sea lion decline in the Pribilof Islands the Aleut Community of St. Paul Island-Tribal Government (ACSPI) has received a 3-year Species Recovery Grant to Tribes from the National Oceanic and Atmospheric Administration (See Press Release).  The objectives of the Steller Sea Lion Biosampling Project are to collect biological samples from Steller sea lions in the Pribilof Island in order to characterize the diet of sea lion and to archive tissues for current and future analyses (e.g. contaminant load).

    As a component of this study, TGSPI Ecosystem Conservation Office (ECO) Island Sentinels conduct regular surveys of Steller sea lion haulout sites on St. Paul Island. These surveys provide the ECO and its management partners with information on the seasonal presence and abundance of Steller sea lions on St. Paul Island and allow it to better target the timing of sea lion scat collections and minimize disturbance to haulout sites.The BeringWatch database record to the right shows the data collected for the observation of Steller sea lions at Reef Point shown in the photo above.

    Detail information for BeringWatch database observation GeoXH-5103_GeoXHDetail-10350.

    For the Species Recovery Grant to Tribes Steller Sea Lion Biosampling Project  the Tribal Government has partnered with the National Marine Mammal Laboratory, Pacific Identifications Ltd., and the Alaska Marine Mammal Tissue Archival Project to assist training, prey identification, and analysis.  This study’s success relies on the partnership and contributions of Unangan subsistence hunters on the Pribilof Islands.

    For more information about this study please contact Pamela Lestenkof at 907-546-3238; pmlestenkof@aleut.com or Lauren Divine at 907-762-8424; lmdivine@aleut.com.