Fisheries-Induced Evolution

Abstract

This chapter develops a basic evolutionary impact assessment of fishing. It does so by combining the size-based theory developed in chapters 3 and 4 with classic quantitative genetics. The impact assessment estimated the selection responses resulting from size-selective fishing on three main life-history traits: size at maturation, growth rate, and investment in reproduction. The predicted selection responses from a fishing mortality comparable to F msy are on the order of magnitude of 0.1 percent per year, smallest for size at maturation and largest for the investment in reproduction. The responses increase roughly proportional to the fishing mortality, so overfishing will not only result in depleted stocks and suboptimal yield production, but it will also lead to faster fisheries-induced evolution.