Impacts of mesh-size regulation of gillnets on the pikeperch fisheries in the Archipelago Sea, Finland

摘要: Abstract In the Archipelago Sea, one of most valuable species in professional and recreational fisheries is pikeperch ( Sander lucioperca ), mainly caught with gillnets. Currently, minimum mesh size (bar length) for gillnet fishing Sea 43–45 mm. Enlarging has been suggested to ensure biological sustainability fishing. The impacts enlarging allowable 50 mm were analysed using a bio-economic simulation model data based on samples from catches 1978 1997, catch statistics. effect uncertainty variable values was examined by specifying probability distribution functions main variables Monte Carlo simulation. According results, yield would be reduced 50% first year, but after some years it stabilise at about 20% higher level than before shift. biomass spawning stock doubled as result larger size, which reduce risk low recruitment benefit long term. However, short-term profitability commercial negative, because take 3 expected present value exceeded prior change 8 net positive. challenge management find solution that both biologically economically reasonable.