Fish 'Personality' Determines The Catch of the Day

Looking for a hefty catch the next time you're out fishing? You might want to get to know the fish of your local lake first. It turns out that the personality of a fish has a lot to do with how likely you are to catch it.

That's at least according to a study recently published in the Canadian Journal of Fisheries and Aquatic Sciences, which details how a fish's vulnerability to angling can be predicted by observing individual differences in everyday behavior.

It's easy to assume that the fish that eventually winds up on your line is either too curious or too hungry to be wary of bait on a hook. However, not all fish are created equal in their curiosity or appetite. Given the right personality, a fish may never be caught.

This was determined after experts conducted a series of novel experiments at the University of Eastern Finland and the Finnish Game and Fisheries Research Institute.

After observing a brown trout population reared in traditional and enriched hatchery environments, the experts noted various differences in "fish personality" based on their day-to-day behavior. When transferred to semi-natural stream and pond environments where fishing occurred, long term observation revealed that, predictably, cautious fish out-lived their more curious fellows.

The more willing a brown trout was to explore new environment in behavioral tests, the more likely it was to be snagged by an angler later on. Likewise, fish who were cautious about eating unfamiliar natural food items in the ponds were found to be incredibly vulnerable to angling simply because of their hunger.

Interestingly, over time the populations in a pond would grow more cautious and difficult to catch. However, this effect was mitigated given a large enough population.

The researchers also note that fish reared in enriched hatchery environments - modified to resemble natural environments - were more likely to develop cautious personalities and live off natural resources, while fish raised in traditional hatcheries were found to be more vulnerable.

The authors suggest enriching hatchery environments to both increase the "sporting" nature of fisheries and to preserve populations.