Fish may be evolving to evade capture from the nets on commercial fishing trawlers, according to new research.
The study by the University of Glasgow has shown that fast-swimming, fitter fish are less likely to be trapped by fishing nets. Over time, this could lead to physiological changes in fish populations. “The selective removal of poor-swimming fish could alter the fundamental physical makeup of descendant populations that avoid fisheries capture, ” said Shaun Killen, the study’s lead researcher.
By simulating trawling with schools of wild minnows, researchers could see whether individual fish were more susceptible to capture. They also measured the swimming ability, metabolic rate and indicators of physical fitness in 43 fish.
The researchers hope to carry out a similar study on fish in the wild.