Current debates about the efficacy of no-take marine reserves in protecting large pelagic fish such as tuna and sharks have usually not considered the evolutionary dimension in this issue, which emerges because the propensity to swim away from a given place, like any other biological trait, will probably vary in a heritable fashion among individuals.
This study investigates, based on spatially explicit simulations, whether selection to remain inside a marine reserve to avoid higher fishing mortality can lead to evolution of more philopatric* fish.
The results of the simulations predict that the evolution of decreased movement rate following the establishment of marine reserves would lead to higher within-reserve population size relative to situations with no heritable variation in movement rate and, thus, augmenting the efficacy of marine reserves. Additionally, the authors state that even when movement rates did not evolve substantially, marine reserves were an effective tool for the conservation of fish populations when movement rates were low or when reserves were very large.
The study also predicts that higher fishing mortality (e.g. overfishing) outside the reserves would strengthen selection pressure and lead to faster evolution of movement rate. In this scenario, marine reserves can act as an important insurance policy against failed target-based management.
The authors conclude that altogether their results provide support of the use of large marine reserves as a tool for the conservation of large pelagic fishes.
*Philopatry: the tendency of an organism to stay in or habitually return to a particular area
Mee JA, Otto SP, Pauly D (2017) Evolution of movement rate increases the effectiveness of marine reserves for the conservation of pelagic fishes. Evolutionary Applications 10:444-461