title: Quantifying selection differentials caused by recreational fishing: development of modeling framework and application to reproductive investment in pike (Esox lucius).
abstract: Methods for quantifying selection pressures on adaptive traits affected by size-selective fishing are still scarce, and none have as yet been developed for recreational fishing. We present an ecologically realistic age-structured model specifically tailored to recreational fishing that allows estimating selection differentials on adaptive life-history traits. The model accounts for multiple ecological feedbacks, which result in density-dependent and frequency-dependent selection. We study selection differentials on annual reproductive investment under size-selective exploitation in a highly demanded freshwater recreational fish species, northern pike (Esox lucius L.). We find that recreational angling mortality exerts positive selection differentials on annual reproductive investment, in agreement with predictions from life-history theory. The strength of selection increases with the intensity of harvesting. We also find that selection on reproductive investment can be reduced by implementing simple harvest regulations such as minimum-size limits. The general, yet computationally simple, methods introduced here allow evaluating and comparing selection pressures on adaptive traits in other fish populations and species, and thus have the potential to become a tool for evolutionary impact assessment of harvesting.
authors.affiliation: Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin, Germany ; Inland Fisheries Management Laboratory, Faculty of Agriculture and Horticulture, Institute of Animal Sciences, Humboldt-University of Berlin Berlin, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Arlinghaus
authors.affiliation: Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin, Germany ; Evolution and Ecology Program, International Institute for Applied Systems Analysis Laxenburg, Austria.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Matsumura
authors.affiliation: Evolution and Ecology Program, International Institute for Applied Systems Analysis Laxenburg, Austria.
authors.forename: Ulf
authors.initials: U
authors.lastname: Dieckmann
keywords: angling; fisheries-induced evolution; life history; minimum-size limit; size-selective exploitation