ices how to count fish for management

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ICES provides advice on state, exploitation and management targets for fish stocks How?

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Page 1: ICES How to count fish for management

ICES provides advice on state, exploitation and management targets for fish stocks

How?

Page 2: ICES How to count fish for management

Information from fish

• Length

• Weight

• Age

Page 3: ICES How to count fish for management

Information on population trends: surveys

• Trawls• Acoustics• Plankton• TV

Research vessels & industry

Page 4: ICES How to count fish for management

Information from catch

• Amount• Location• Timing• Bycatch

From ports, log books & observers

Page 5: ICES How to count fish for management

How do we use this information?Take a stock of fish:

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Every stock has underlying structure

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Add fishing…

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Mortality rate

Change in thenumbers at age

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We also measure the catch

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• Observed mortality rates

• Catches recorded

Equations and simulations are used to combine the information.

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Also observations of trends in populationsfrom surveys.

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This produces a stock assessment

North Sea herring

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To provide the advice for next year’s catches

We project forward with our best knowledge(maturity, growth, recruits, impact of fishing gear, natural death etc) across a range of fishing scenarios.

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Scenarios set out in management plans

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All management plans in the ICES area are tested using simulations

Simulations of Atlantic mackerel multiannual management strategy at different fishing mortalities

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Framework for advice

International agreements and policies:• UN Convention on the Law of the Sea (UNCLOS 1982) -MSY• UN Conference on Environment and Development (UNCED, 1992) -precautionary approach• UN Straddling Fish Stocks Agreement of 1995 (UNFSA 1995) - precautionary approach• Convention on Biological Diversity (UN CBD, 1992) - ecosystem approach• Johannesburg Declaration of the World Summit on Sustainable Development (WSSD UN 2002)-

ecosystem approach & MSY

National and regional legislation:including CFP, MSFD, Norwegian Marine Resources Act, Russian Federal Law on Fisheries, Icelandic Fisheries Management Act, Faroe Islands Fisheries Management Act

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Reference pointsPrecautionary Approach

Populations need to be maintained within safe biological limits -Certain that reproductive success is not impaired

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Reference pointsmaximum sustainable yield (MSY)

ICES interpretation of MSY is maximization of average long-term yield from sustainable stocks

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Reference pointsmaximum sustainable yield (MSY)

Ecosystem Approach

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Use of reference points: current and future

North Sea herring

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State of the stocks North Sea overview