Estimating abundance, fishing mortality and migration rates by area

Estimating abundance, fishing mortality and migration rates by area

SCRS/97/84
Estimating abundance, fishing mortality and migration rates by area, using the spatial VPA
methodology. Application to yellowfin tuna in eastern and western Atlantic
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INTRODUCTION
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1. DATA AND MÉTHOD
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Contrary to the catchability qt, the assumption that the coefficient q’t is spatially
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1.1. The spatial VPA methodology
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1.2. Extending the method to several fleets
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1.3. Application to Atlantic yellowfin tuna
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2. RESULTS
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2.1. Global and local fishing mortalities
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2.2. Fish numbers in each zone and migration rates
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25000000
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moy%N1
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effectifs relatifs moyens
effectifs
20000000
15000000
N1
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4500000
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effectifs
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3. DISCUSSION AND CONCLUSION
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