Differences in metabolic rates of exploited, unexploited fish populations

Their research compared populations of largemouth bass (Micropterus salmoides) taken from unexploited reference populations in the state of Connecticut and compared their resting metabolic rates (RMR) with populations taken from popular inland recreational fisheries.

Differences among exploited and unexploited populations suggest that recreational fishing may select against high metabolic rate fish which tend to be more aggressive and therefore easier to catch. In the long term, this could affect the tropic dynamics within an entire body of water as well as the quality of the fishery.

"We collected baby fish from each type of lake or reservoir and transferred them to a protected location with no anglers and no predation from larger fish," Hessenauer says. "They grew up in the same environment so they all experienced the same rearing conditions. The next year, we measured their resting metabolism. We found that significantly more individuals taken from the lakes where fishing was allowed had lower metabolic rates relative to the fish taken from the protected bodies of water, even though neither had actually spent any appreciable time in their natal environments."