A recent study by Australian and Canadian researchers states that commercial fishing boats favour bold, fast-growing fish, which potentially affecting the ability of the fish population to recover. The scientists found that the regulations governing the size of fish caught are not sufficient to stop human driven evolution. They simulated an intensive gillnet fishery, where mesh nets are cast over large areas to catch as many fish as possible, in two rainbow trout stocked experimental lakes in Canada.
According to Dr Peter Biro from the University of Technology Sydney and Professor John Post of the University of Calgary in Canada, the fish that survive commercial harvesting tended to be more meek, less active and carry less eggs. Dr Biro said that the bold fishes are more active in finding food and grow fast and are quickly taken by commercial fishing. It is fact that the bold fish are more vulnerable as they swim around more and are less likely to shy away from fishing gear, says Dr Biro.
The study highlights the importance of adopting behavioural and evolutionary ecology perspectives to fishermen understanding of the short and long-term effects of fish harvest and the need to foster collaboration between fishery scientists and evolutionary ecologists, explained Dr Biro. He also said that the result of this study would apply to fish populations other than the rainbow trout and distinct methods of fishing apart from gillnets.
