Largemouth bass exposed to recreational fishing - even catch-and-release fishing - have been evolving to be more difficult to catch.

New work by Jan-Micheal Hessenauer, a Ph.D student in the Department of Natural Resources and the Environment at the University of Connecticut and his colleagues, compared bass exposed to heavy fishing pressure, and those in protected lakes.

They found that the heavily exploited fish had a lower metabolic rate, which corresponds to less activity & aggression, and which, in turn, tends to make fish harder to catch. What they suspect is that the stress and energetic costs of more aggressive fish who are caught - even if released - has resulted in reduced reproductive success. They're also concerned that this makes the fish less ecologically capable as top predators.

Related Links

- Paper in PLoS One

- University of Connecticut release

