Plankton impact on the Faroe Plateau cod

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Plankton impact on the Faroe Plateau cod

• Eilif Gaard
• Faroese Fisheries Laboratory
• Tórshavn, Faroe Islands

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Faroe Shelf Ecosystem

• Water mass separated from the surrounding ocean
• Shelf ecosystem
• Co-fluctuation in all trophic levels

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Copepods vs. bottom depthAround the Faroe shelf,
late June
Gaard and Reinert, 2002
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Copepods on the Faroe shelf1989-2001
(Gaard, 2003)
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Faroe shelfmonitoring

• Late April
• Late June
• Feb May July Aug. - Nov
• Coastal station weekly

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Phytoplankton zooplankton abundanceSpring
2004
Feb March April May
June
(Eliasen, 2005)
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Chlorophyll aFaroe shelf, 1997-2004
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Calc. new primary productionCentral Faroe shelf,
spring summer
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Cod spawning grounds
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When is year class strength determined (1)
(Steingrund and Gaard, 2005. 0-group data from J.
Reinert)
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When is year class strength determined (2)
August-March-August
(Steingrund and Gaard, 2005)
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(Steingrund and Gaard, 2005)
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Recruitment of 2 years old cod and haddock
SSB and recruitment of 2 years old cod (YC)
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Cod haddock recruitment (age 2)and Primary
production
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Recruitment of 2 years old cod and haddock
SSB and recruitment of 2 years old cod (YC)
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Primary production growth rates
Cod
Haddock
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Including haddock and saithe
(Steingrund and Gaard, 2005)
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Including haddock and saithe
(Steingrund and Gaard, 2005)