Recent Comments

    Categories

    • No categories

    Endangered Steller Sea Lion scat samples collected in the Pribilof Islands

    ECO staff and colleagues during the scat collection trip to Walrus and Otter Islands.

    The Steller sea lion population in the Pribilof Islands has declined to extremely low levels and the sole remaining breeding rookery at Walrus Island is currently in danger of extinction. Over the last 50 years pup production on Walrus Island has declined by over 90%, from 2,866 in 1960 to only 29 pups born in 2005. Similar to the decline of the western Alaskan population as a whole, the cause of the sea lion decline in the Pribilof Islands in recent decades remains unexplained. The highest ranked threats to the recovery of the western Alaska sea lion population listed in the Steller Sea Lion Recovery Plan are environmental variability, competition with fisheries, killer whale predation and toxic substances.

    To help determine the cause of the decline the Aleut Community of St. Paul Island-Tribal Government has received a  Species Recovery Grant to Tribes from the National Oceanic and Atmospheric Administration.  The objectives of this study 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).  Diet information will be assessed through three components:  1) prey identification of hard parts from scats collected from haulout and rookery areas; 2) identifiable prey recovered from the digestive tracts of beachcast (i.e. dead/stranded) and subsistence hunted animals.

    In October 2011 the Aleut Community of St. Paul Island Tribal Government Ecosystem Conservation Office conducted two successful scat collection trips to Walrus and Otter Islands. We went to Walrus Island on October 11 collected 42 scat samples from the Steller sea lion rookery located there.  We also made it to Otter Island on October 16 and collected 49 scat samples from the Steller sea lion haulout.

    Collecting scats on Walrus Island.

    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.

    Observations and counts of Steller sea lions and other marine mammals as well as information on any disturbance to species present during scat collection operations are entered into the BeringWatch database. The subsistence harvest module of the BeringWatch database will be used during 2012 to track information on the collection of tissues samples and digestive tracts from beachcast (i.e. dead/stranded) and subsistence hunted animals

    For more information about this study please contact Pamela Lestenkof at pmlestenkof@tgspi.com.

    Leave a Reply