Ecosystem Variation in the Southeastern Bering Sea

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Ecosystem Variation in the Southeastern Bering
Sea

• George L. Hunt, Jr1., Phyllis Stabeno2, and Jeff
  Napp3

1 University of Washington 2 NOAA Pacific Marine
Environmental Laboratory 3 NOAA Alaska Fisheries
Science Center
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Major Issues

• Evidence of Past Changes
• Loss of sea Ice, warming sea water temperatures
• Diminishing summer zooplankton biomass
• Changes in biomass and distribution of fish
• Changes in marine bird and mammal distributions
• Anticipating Future Changes
• How will further loss of sea ice affect the
  ecosystem?
• How will zooplankton populations respond, and
  will we lose large species of zooplankton?
• Will new species of fish competitors or predators
  emerge?
• What role will whales play?

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Loss of Winter Sea Ice
Winter-time (Dec - Jan - Feb) sea
ice has decreased in the Bering Sea over the last
five decades (1954 - 2005)
P. Stabeno J. Overland, PMEL
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Vertically Averaged Temperature (C) at Mooring M2
P. Stabeno, PMEL
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Fur Seal Pups at the Pribilof Is.
The Bering SeaIs it just a Warmer Barents Sea?

• George L. Hunt, Jr.
• University of California, Irvine
• and
• Bernard Megrey
• NOAA Alaska Fisheries Science Center

NMML, NOAA
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Herring Recruitment
Togiak District, Bristol Bay
Fred West, Ecosystem Chapter NPFMC 2007 SAFE
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Walleye Pollock Abundance
Courtesy Ianelli et al. 2007 SAFE
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Walleye Pollock Abundance
Numbers of age-1 pollock, in millions of
individuals
Courtesy J. Ianelli et al. 2007 SAFE
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Water Temperature Affects Fish Distribution
2
4
0
2
0
Pollock CPUE (shades relative kg / hectare) and
bottom temperature (isotherms 0º, 2º, and 4º C)
from summer bottom-trawl surveys
Courtesy Jim Ianelli et al. 2007 SAFE
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Biomass of Medusae in the S.E. Bering Sea
G. Walters, NMFS
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Widespread Plankton Decline
J. Napp / N. Shiga
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Copepod Abundance
(Smith Vidal, 1986)
Courtesy of Napp and Shiga
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Kittiwake Reproduction vs Adult Pollockon the
Eastern Bering Sea Shelf
P. Livingston, NMFS / USFWS
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Major Issues

• Evidence of Past Changes
• Loss of sea Ice, warming sea water temperatures
• Diminishing summer zooplankton biomass
• Changes in biomass and distribution of fish
• Changes in marine bird and mammal distributions
• Anticipating Future Changes
• How will further loss of sea ice affect the
  ecosystem?
• How will zooplankton populations respond and will
  we lose large species of zooplankton?
• Will new species of fish competitors or predators
  emerge?
• What role will whales play?

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Integrated Bering Sea Ecosystem Study
BASIS FOCI NPCREP AOOS
BIESRP
AFSC NMML PMEL
OPP Arctic Natural Social Sciences
USFWS USGS
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The Bering Ecosystem Study (BEST)

• Program designed to understand and predict
  consequences of climate change for the Bering Sea
  marine ecosystem
• End to End scope Climate, physics, primary
  production, zooplankton, fish, seabirds, marine
  mammals and people

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BEST Information Sources

• Science Plan, available in hard copy at
• Arctic Research Consortium of the U.S. (ARCUS)
• 3535 College Road, Suite 101, Fairbanks, AK
  99709
• Phone [phone] Fax [phone]
• Planning Office c/o George L. Hunt, Jr.
• School of Aquatic Fishery Sciences
• University of Washington, Seattle
• Email geohunt2_at_u.washington.edu
• Web Site
• http//www.fish.washington.edu/best

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Ice, Wind, Bloom and Copepods
Early Ice Retreat Late Bloom, Warm
Water Large Copepod Biomass
Late Ice Retreat Early Bloom, Cold
Water Small Copepod Biomass
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Diets of Adult and Juvenile Walleye Pollock
JUV.
ADULT
Courtesy Ianelli et al. 2007 SAFE
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Short-tailed Shearwaters (Puffinus tenuirostris)
Photos G. Hunt and M. Warner
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Short-tailed Shearwater Distribution and
Abundance
Figures courtesy of J. Jahncke
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Abundance of Seabird Foraging Guilds
Figure courtesy of J. Jahncke
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Observations of Baleen Whales near the Pribilof
Islands