A Fish's Personality Determines Whether It's Hooked or Avoids the Line

Whether or not you land a fish may not depend on the type of lure you use, but on the fish's personality. Scientists have found that differences in moving activity in a novel environment are linked to individual differences in vulnerability to angling.

In this case, the scientists examined the behaviors of brown trout. More specifically, the scientists conducted long-term observations of individual behavior in groups and authentic angling trials to analyze if behaviors predicting the vulnerability to fishing in brown trout reared in traditional and enriched hatchery environments.

In the end, the researchers found that the more active the brown trout were to explore new environments, the more vulnerable they were to fishing. Yet fish body size or individual differences in swimming activity played no role in their vulnerability. In other words, the fish's personality was the main thing that determined whether or not it would be caught.

In enriched hatchery rearing, ponds are modified to resemble natural environments. In addition, feeding takes place at an irregular schedule. Yet brown trout reared in traditional environments tend to be more exploratory than those reared in enriched environments. This makes them more vulnerable to fishing.

So what does this mean? By introducing natural elements to fish hatcheries, scientists can better ensure fish survival later in life if they're released into the wild. This has major implications for fish conservation and could show a new way to better manage fisheries in the future.

The findings are published in the Canadian Journal of Fisheries and Aquatic Sciences.