1 / 19

Gray Whales as Sentinels of Alaskan Ecosystem Variability

Gray Whales as Sentinels of Alaskan Ecosystem Variability. Sue E. Moore NOAA/AFSC @ APL-UW. Co-Investigators. Kate Stafford (APL-UW) Kate Wynne (UAF – Kodiak) Jackie Grebmeier (UT) Dave Rugh (NOAA/AFSC/NMML) Wayne Perryman (NOAA/SWFSC/PRD) Jim Overland (NOAA/PMEL). Gray Whale Basics.

amato
Download Presentation

Gray Whales as Sentinels of Alaskan Ecosystem Variability

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Gray Whales as Sentinels of Alaskan Ecosystem Variability Sue E. Moore NOAA/AFSC @ APL-UW

  2. Co-Investigators • Kate Stafford (APL-UW) • Kate Wynne (UAF – Kodiak) • Jackie Grebmeier (UT) • Dave Rugh (NOAA/AFSC/NMML) • Wayne Perryman (NOAA/SWFSC/PRD) • Jim Overland (NOAA/PMEL)

  3. Gray Whale Basics • Only member of Eschrichtiidae • Feeding generalists • Two populations in North Pacific: ENP & WNP • ENP pop. ~ 18K whales *de-listed in late 1992 **1999-2000 mortalities, post 1997-98 El Nino

  4. Ecosystem Sentinels?‘Weight of Evidence’ • One-week delay in southbound migration timing, coincident with NPAC regime shift (Rugh et al. 2001) • Calving rates positively correlated with ice-free Chirikov Basin (Perryman et al. 2002) • Absence of feeding GW in Chirikov Basin,coincident with decline in benthic infauna (Moore et al. 2003) • Feeding whales year-round near Kodiak(Moore et al.*) • Calls detected year-round near Barrow(Stafford et al.*)

  5. ENP Gray Whale Range

  6. Rugh’s ObservationsShift in migration timing - PDO • Census @ Granite Canyon since 1967 • Median Southbound dates: • 8 JAN pre-1980 • 15 JAN post-1980 • 1-week shift, co-incident with increase in calf sightings North of Mexico (Shelden et al. 2004) [PDO = N. Mantua]

  7. Perryman’s Observations-sea ice = +recruitment

  8. Absence of Feeding GW in the Chirikov Basin…

  9. Co-incident with Decline in Infaunal Benthic PreyJ. Grebmeier’s Benthic Time Series

  10. So, if not the Chirikov Basin, where areGray Whales Feeding? • 10s to 100s of whales seen feeding year-round offshore Kodiak Island K. Wynne’s surveys • ‘many’ west of the IDL in Southern Chukchi Sea • 10s to 100s reported NE Barrow by whalers • 10s of whales feeding near Sitka J. Straley obs.

  11. ‘Kodiak’ Gray Whales, 1999-2004100s of whales in 2000 & 2001

  12. Feeding on dense swarms of cumaceans • Benthic sampling from small boat, 15-20 August 2002 Jackie Clement • Extremely high cumacean densities @ 4 stations: 48,000-86,000/m2 • Amphipods nearly absent

  13. Meanwhile, Recorders Near Barrow • ARPs deployed OCT03-SEP04,via NSF-SBI cruises • Part of broader AK array; BioScience, January 2006 With thanks to: L. Munger (SIO) R. Pickart (WHOI)

  14. Detect Gray Whale Callsthroughout winter `04 [until May]

  15. AVHRR sea ice image: 25 January 2004‘breathing room’ [image: Hajo Eiken]

  16. Sea Ice and Productivity: Conceptual models

  17. K. Wynne’s - ‘So What?’ • Gray whales are not behaving “like they used to”; is it just population growth/recovery? • Gray whales track prey shifts and thereby provide insight to local ecology. [Duffus Lab] • Population & environmental time series supports modeling approach. [J. Brandon] • Species should be considered NPAC/Arctic Ecosystem Sentinel – under development by NOAA Ecosystem Goal Team [S. Swartz]

  18. Ultimate Goals • Inclusion of gray whales (& other large whales) in Ecosystem Models. • Capability to interpret Ecosystem Variability via population and health assessment of large whales. • Improved prediction/response to mortality events.

  19. THANKS for Support • NOAA/AFSC/NMML: GW census, aerial surveys, Kodiak prey assessment & ARPs (via Scripps) • NOAA/SWFSC: calf census, aerial surveys, sea ice analyses • NOAA/PMEL: conceptual model & web support • UAF/GAP Program: Kodiak logistic support • NSF/Shelf-Basin-Interaction Program: logistic support for Beaufort recorders

More Related