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ESEE 2005

A Bioeconomic Analysis of the Northern Baltic Salmon Fishery: Management of Competing Sequential Fisheries Kulmala Soile , Laukkanen Marita, Michielsens Catherine. ESEE 2005. Structure of the talk. Biological context Social context Different salmon fisheries Dealing with complexity

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ESEE 2005

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  1. A Bioeconomic Analysis of the Northern Baltic Salmon Fishery: Management of Competing Sequential Fisheries Kulmala Soile, Laukkanen Marita, Michielsens Catherine ESEE 2005

  2. Structure of the talk • Biological context • Social context • Different salmon fisheries • Dealing with complexity • Results

  3. Biological and social context • Decreasing number of salmon stocks • damming, pollution, overfishing • Tightened regulation • time and gear restrictions • Conflicts between different user groups • commercial versus recreational fishery • Active salmon fishery policy debate

  4. Biological context Bothnian Bay Gulf of Bothnia • Migration routes • Feeding areas • Present salmon rivers • Past salmon rivers Bothnian Sea Gulf of Finland Baltic Proper

  5. Social context • Salmon Action Plan (SAP) • conservation • yield maximization • Different fisheries • fishing time and place • gear • salmon price • fishing costs • recreational • commercial

  6. Social context RI Salmon fisheries CTN • Offshore driftnet (ODN) In 2006 2. Offshore longline (OLL)  CDN 3. Coastal driftnet (CDN) OLL 4. Coastal trapnet (CTN)  ODN 5. River (RI)

  7. Objectives of present study • Realism to bioeconomic models • Charles and Reed (1985) • Laukkanen (2001) • Contribution to fishery policy • Optimal policy • Effort allocation for active fisheries

  8. Dealing with complexity • Age-structured dynamic bioeconomic model for salmon • 6 state variables • 6 transition equations (4 different) • 5 decision variables

  9. Analysis • Steady state harvest policy • Optimal effort trajectories for active fisheries

  10. Steady state RI Salmon fisheries • Commercial coastal trapnet (CTN) • 75 000 geardays • (24 000) • 46 663 kg CTN • Recreational river(RI) • 1730 angling days • (8145) • 976 kg

  11. Optimal trajectory Coastal trapnet effort

  12. Optimal trajectory River effort

  13. Extensions • Uncertainty • recruitment • stock measurement • Comparisons to biomass dynamic model

  14. Thank you for your attention soile.kulmala@helsinki.fi

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