Who or What is Regulating Zooplankton Production in the Southeastern Bering Sea?

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Who or What is Regulating Zooplankton Production
in the Southeastern Bering Sea?

• Jeffrey M. Napp1, George L. Hunt2, Jr., Sue E.
  Moore1, and Christine T. Baier1
• 1NOAA Fisheries, Alaska Fisheries Science
  Center
• 2School of Fisheries and Aquatic Sciences, Univ.
  Washington

Funded Provided By North Pacific Research
Board National Science Foundation NOAAs
North Pacific Climate Regimes and Ecological
Productivity
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Control From Below Does It Occur?
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Temperature Limitation

• Huntley Lopez (1992)
• R2 0.91
• Hirst Lampitt (1998)
• Broadcast
• T BW R2 0.49
• Sac
• T only R2 0.52

Growth Rate (d-1)
Temperature (ºC)
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Bering Sea Temperature Limitation
3.8 C
3.4 C
0.3 C
Coyle and Pinchuk (2002)
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Temperature Limitation ?
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Temperature Limitation
Calanus marshallae
 
Baier and Napp (2003)
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Temperature Limitation
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Food Limitation
Calanus finmarchicus
St. Paul Island Wind Data
Georges Bank
Campbell et al. (2001)
P. Stabeno, NOAA - PMEL
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Control From Above Does It Occur?
Baleen Whales
Seabirds
Fish
Gelatinous Zooplankton
Other Crustacean Zooplankton
Mesozooplankton
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Control from Above
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(No Transcript)
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Conclusions

• Both control mechanisms are operative how do
  they interact?
• Need growth rate measurements at low
  temperatures.
• Species composition affects the result.
• Spatially-explicit rates, especially predation
  mortality.
• Simulations/models important to examine different
  mechanisms under different conditions.