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Anne Hoover-Miller Alaska SeaLife Center

Changes in Harbor Seal Population Dynamics in Aialik Bay. Anne Hoover-Miller Alaska SeaLife Center. Photo: DW Miller. Gulf of Alaska Harbor Seal Trend: Tugidak Island. Tugidak Island 1974-1990’s - 90% 1994-2000: Molt 3.0%/yr

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Anne Hoover-Miller Alaska SeaLife Center

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  1. Changes in Harbor Seal Population Dynamics in Aialik Bay Anne Hoover-Miller Alaska SeaLife Center Photo: DW Miller

  2. Gulf of Alaska Harbor Seal Trend: Tugidak Island Tugidak Island 1974-1990’s - 90% 1994-2000: Molt 3.0%/yr Pups 5.4%/yr Kodiak Island area 1993-2002 7.2%/yr From: Pendleton and Wolfe 2005 Alaska Department of Fish & Game

  3. From: Pendleton and Wolfe 2005 Alaska Department of Fish & Game Harbor Seal Population Trend: Prince William Sound PWS 1984-1997 - 63% 1990-1999 - 3.1%/yr 2000-2004 ?

  4. Kenai Fjords Study Areas • Kenai Fjords Region • Focal areas: • Aialik Bay: Glacial Ice • Day Harbor: Land Haulouts • Regional Surveys

  5. B. Hoover Aialik Bay: Seals on Ice • Tidewater Glacier Habitat • Aialik Glacier • Head of 30 km long fjord • Pedersen Glacier • Abuts tidally influenced lake • Counts have been conducted intermittently since 1979

  6. B. Hoover Glacier Habitats Differ Aialik Glacier Pedersen Glacier

  7. Aialik Glacier: Ice on the move

  8. Pedersen Lake

  9. Past Research: 1979-2001 • 1979-1981: • Behavior and Ecology of Harbor Seals Inhabiting Glacial Ice in Aialik Bay (Hoover 1983) • Population dynamics • Demography • Habitat use • Response of Seals to Human Disturbance (Murphy and Hoover 1981) • NPS continued monitoring, with emphasis in 1989, 1994, and 1995.

  10. Current Research: 2002-2005 • Remote Video Monitoring • Ecology & Population Biology • Glacier Ice Environments • Human Interactions Caroline Jezierski Poster • Aerial Surveys

  11. 2002-2005: Remote Video Monitoring • Camera control commands sent from ASLC to cameras via UHF transmissions • Video transmission received via microwave

  12. Aialik Bay Trends:1979-2005 Total Seals 1980-1989 - 84% (17%/yr) 1989-2002 Stable 2002-2005 +90% (45%/yr) Pups 1980-1989 - 74% (13%/yr) 1989-1994 -12%/yr 2003-2005 +3%/yr

  13. Aialik Bay Trends: 2002-2005 Total Seals (Molt) 2002-2005 Pups 2002-2005

  14. 2004 Regional Trends • Molt: • 1,165 seals in 2004 • 1,508 seals in 2005 • _______ • 30% Regional Increase during Molt • Pupping, Excluding McCarty Fjord: • 541 seals in 2004 • 546 seals in 2005 • _______ • Similar numbers during Pupping 2005

  15. Proportion of Tugidak, Aialik, Day Harbor and Prince William Sound(relative to 1983): 1976-2005

  16. 1983-2005How similar are trends throughout the Gulf of Alaska?

  17. EVOS Proportion of AT1 Pod Killer Whales relative to seal populations they prey on 1983-2005

  18. Summary • Population decline of harbor seals included land and glacial ice habitats on the outer Kenai Peninsula • Magnitude of decline since 1983 shows similarities between areas • Recovery in each area shows different trajectories that may be related to local environmental change (bottom-up factors) • Stabilization and recovery in the Kenai Fjords and Prince William Sound coincides with reduced numbers of killer whales (top-down effects).

  19. Acknowledgements Collaborators • P. Armato, OASLC, NPS • S. Atkinson, ASLC, UAF/SFOS • SeeMore Wildlife Inc. • Port Graham Corporation • U.S. Fish and Wildlife Service, National Maritime Wildlife Refuge System • National Marine Fisheries Service • University of Alaska, Fairbanks Field and Video Monitoring Personnel: R. Day, K. Oakley, T. Carpenter, D. Miller, C. Miller, M. Tetreau, J. Pfeiffenberger, S. Pfeiffenberger, G. Smith, K. Link, W. Bryden, J.Welsh, S. Brennan, P. Salzman, K. Wilson, K. Felitz, S. Aughe, L. O’Brien, L. Dickinson, J. Follin, T. Mauro, M. Sternberg, K. Heffron, R. Pearce and C. Jezierski. Permits: NMFS 881-1673 881-1724, NPS KEFJ-2004-SCI-0001, USFWS745-03-045

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