A Bioeconomic Analysis of A Bioeconomic Analysis of the Northern Baltic Salmon the Northern Baltic Salmon

Fishery: Management of Fishery: Management of Competing Competing

Sequential Fisheries Sequential Fisheries

Kulmala Soile, Laukkanen Marita, Michielsens Catherine

ESEE 2005

Structure of the talkStructure of the talk

Biological contextBiological context Social contextSocial context Different salmon fisheriesDifferent salmon fisheries Dealing with complexityDealing with complexity ResultsResults

Biological and social contextBiological and social context

Decreasing number of salmon stocksDecreasing number of salmon stocks damming, pollution, overfishingdamming, pollution, overfishing

Tightened regulationTightened regulation time and gear restrictionstime and gear restrictions

Conflicts between different user Conflicts between different user groupsgroups commercial versus recreational fisherycommercial versus recreational fishery

Active salmon fishery policy debateActive salmon fishery policy debate

BiologicBiological al contextcontext

Baltic Proper

Bothnian Sea

Gulf of Finland

Bothnian Bay

Gul

f of B

othn

ia

Migration routes Feeding areas Present salmon rivers Past salmon rivers

Social contextSocial context

Salmon Action Plan (SAP)Salmon Action Plan (SAP) conservationconservation yield maximizationyield maximization

Different fisheriesDifferent fisheries fishing time and placefishing time and place geargear salmon pricesalmon price fishing costsfishing costs recreationalrecreational commercialcommercial

Latvia

Lithuania

Poland

Russia

Russia

Finland

Sweden

0 100 200 km

Latvia

Lithuania

Poland

Russia

Russia

Finland

Sweden

0 100 200 km

BothnianSea

BothnianBay

Baltic Main Basin

Main Basin

Estonia

Åland Sea

Gulf of Finland

Social contextSocial context

ODN

Salmon fisheries

1. Offshore driftnet (ODN)

2. Offshore longline (OLL)

3. Coastal driftnet (CDN)CDN

4. Coastal trapnet (CTN)

CTN

5. River (RI)

RI

In 2006

OLL

Objectives of present studyObjectives of present study

Realism to bioeconomic modelsRealism to bioeconomic models Charles and Reed (1985)Charles and Reed (1985) Laukkanen (2001)Laukkanen (2001)

Contribution to fishery policyContribution to fishery policy Optimal policyOptimal policy Effort allocation for active fisheriesEffort allocation for active fisheries

Dealing with complexityDealing with complexity

Age-structured dynamic Age-structured dynamic bioeconomic model for salmonbioeconomic model for salmon 6 state variables6 state variables 6 transition equations (4 different)6 transition equations (4 different) 5 decision variables5 decision variables

AnalysisAnalysis

Steady state harvest policySteady state harvest policy Optimal effort trajectories for active Optimal effort trajectories for active

fisheriesfisheries

Latvia

Lithuania

Poland

Russia

Russia

Finland

Sweden

0 100 200 km

Latvia

Lithuania

Poland

Russia

Russia

Finland

Sweden

0 100 200 km

BothnianSea

BothnianBay

Baltic Main Basin

Main Basin

Estonia

Åland Sea

Gulf of Finland

Steady stateSteady stateSalmon fisheries

Commercial coastal trapnet (CTN)• 75 000

geardays (24 000)• 46 663 kg

CTN

Recreational river (RI)• 1730 angling days (8145)• 976 kg

RI

Optimal trajectoryOptimal trajectoryCoastal trapnet effort

Optimal trajectoryOptimal trajectoryRiver effort

ExtensionsExtensions

UncertaintyUncertainty recruitmentrecruitment stock measurementstock measurement

Comparisons to biomass dynamic Comparisons to biomass dynamic modelmodel

soile.kulmala@helsinki.fi