Heatwaves appear to trigger heritable gene expression changes that may help make the fish more tolerant of thermal stress, researchers report in novel study.
Heatwaves appear to trigger heritable gene expression changes that may help make the fish more tolerant of thermal stress, researchers report in novel study.
Brook trout may have a genetic trick up their scales when it comes to adapting, with limitations, to heatwaves that threaten their existence. Scientists have known for years that brook trout — an iconic coldwater fish species native to streams and lakes in the eastern United States and Canada — are extremely vulnerable to warming temperatures, with more than half of their habitats characterized as highly sensitive and highly vulnerable to such changes by U.S. Forest Service researchers in 2010. Now, a novel study led by researchers at Penn State suggests that brook trout are capable of mounting a protective genetic response to thermal stress that can be passed on from one generation to the next.
“The responses to heat stress had a high degree of plasticity, with brook trout exhibiting the ability to acclimate and increase tolerance to higher temperatures,” said team leader Jason Keagy, assistant research professor of wildlife behavioral ecology. “Our study covered two heatwaves, and the overall change in expression patterns was more intense during the second heatwave. We think the first heatwave ‘primed’ the response for the second.”
Read more at Penn State
Image: Brook trout, an iconic coldwater fish species native to streams and lakes in the eastern United States and Canada, begin to experience declines in growth rate in water above 61 degrees Fahrenheit and acute heat stress above 68 degrees Fahrenheit. In this study, researchers caught, sampled and released fish in four streams in Pennsylvania. (Credit: Jason Keagy/Penn State)
