An eco-evolutionary perspective on marine reserves

Abstract

Marine reserves are a valuable tool for protecting against human impacts such as harvesting and are expected to support fisheries beyond their boundaries through spillover of juveniles and mature fish. Furthermore, marine reserves could guard against fisheries-induced evolutionary changes in fish life-history traits such as growth and maturation, by protecting phenotypes that are otherwise typically targeted by fishers. However, little attention has been paid to the potential for selection directly on behavioural traits posed by fisheries and to the role that marine reserves may play in buffering or strengthening those processes. Recently, it has been hypothesised that spillover fisheries (operating along the reserve border) could exert strong selection against individuals with a higher tendency to spend time outside the reserve (e.g. individuals with larger home ranges) potentially eroding the fisheries benefits while increasing the conservation effectiveness the of the reserves. I will present case studies on harvested fish species from the Norwegian coast, where we use long-term mark-recapture and telemetry data to quantify individual behaviour and fate in the wild, before and after the implementation of marine reserves. Our studies highlight how such spatial management actions could alter the selection regimes in aquatic systems.