Marine reserves and the evolutionary effects of fishing on size at maturation

TY - JOUR

T1 - Marine reserves and the evolutionary effects of fishing on size at maturation

AU - Miethe, Tanja

AU - Dytham, Calvin

AU - Dieckmann, Ulf

AU - Pitchford, Jonathan W.

PY - 2010/4

Y1 - 2010/4

N2 - Size-selective fishing may induce rapid evolutionary changes in life-history traits such as size at maturation. A major concern is that these changes will reduce population biomass and detrimentally affect yield and recruitment. Although marine reserves have been proposed as a tool for fisheries management, their evolutionary implications have as yet attracted little scrutiny. A simple model is used to investigate whether marine reserves can be expected to mitigate the evolutionary impacts of fishing on maturation size. The adaptive dynamics of size at maturation are analysed based on a stage-structured population model including size-selective fishing and marine reserves with different retention rates. As has been shown before, imposing greater fishing mortality on the largest individuals promotes an evolutionary change towards smaller maturation size. In the model, protecting part of a fish stock using a marine reserve can prevent such fisheries-induced evolution, and this protection critically depends on the type and extent of movement between the reserve and the fished area. Specifically, although the frequent movement of large adults increases catches of large adult fish outside a marine reserve, it also reduces the reserve's effectiveness in preventing fisheries-induced evolution. In contrast, when there is exchange between protected and fished areas through juvenile export alone, a marine reserve can effectively prevent evolution towards smaller maturation size, but does so at the expense of reducing the yield of large adult fish. Differences in the movement behaviour of successive life stages need to be considered for marine reserves, to help make fisheries more sustainable evolutionarily.

AB - Size-selective fishing may induce rapid evolutionary changes in life-history traits such as size at maturation. A major concern is that these changes will reduce population biomass and detrimentally affect yield and recruitment. Although marine reserves have been proposed as a tool for fisheries management, their evolutionary implications have as yet attracted little scrutiny. A simple model is used to investigate whether marine reserves can be expected to mitigate the evolutionary impacts of fishing on maturation size. The adaptive dynamics of size at maturation are analysed based on a stage-structured population model including size-selective fishing and marine reserves with different retention rates. As has been shown before, imposing greater fishing mortality on the largest individuals promotes an evolutionary change towards smaller maturation size. In the model, protecting part of a fish stock using a marine reserve can prevent such fisheries-induced evolution, and this protection critically depends on the type and extent of movement between the reserve and the fished area. Specifically, although the frequent movement of large adults increases catches of large adult fish outside a marine reserve, it also reduces the reserve's effectiveness in preventing fisheries-induced evolution. In contrast, when there is exchange between protected and fished areas through juvenile export alone, a marine reserve can effectively prevent evolution towards smaller maturation size, but does so at the expense of reducing the yield of large adult fish. Differences in the movement behaviour of successive life stages need to be considered for marine reserves, to help make fisheries more sustainable evolutionarily.

KW - connectivity

KW - fitness

KW - life-history evolution

KW - metapopulation

KW - size-structured model

KW - spillover

KW - LIFE-HISTORY EVOLUTION

KW - NORTH-SEA PLAICE

KW - COD GADUS-MORHUA

KW - FISHERIES-INDUCED EVOLUTION

KW - PROTECTED AREAS

KW - REACTION NORMS

KW - SUSTAINABLE FISHERIES

KW - SELECTIVE MORTALITY

KW - DEPENDENT MORTALITY

KW - ADAPTIVE DYNAMICS

UR - http://www.scopus.com/inward/record.url?scp=78149445774&partnerID=8YFLogxK

U2 - 10.1093/icesjms/fsp248

DO - 10.1093/icesjms/fsp248

M3 - Article

SN - 1054-3139

VL - 67

SP - 412

EP - 425

JO - ICES Journal of Marine Science

JF - ICES Journal of Marine Science

IS - 3

ER -