The results of a 15-year study of factors affecting brook trout survival show that the biggest issues are higher summertime temperatures and “extreme rain” events. Due to climate change, these trends are probably going to continue.
Co-author Ben Letcher, fisheries biologist at the U.S. Geological Survey and adjunct faculty in environmental conservation at the University of Massachusetts Amherst, says, “It took years of sampling four streams and tracking more than 15,000 individual fish, but we feel we can account for about 90 percent of the yearly variation in abundance. The bottom line is that high summer temperatures are bad. That is unfortunate because summer air temperature is expected to increase with climate change and extreme rain is also expected to increase, especially in the spring when vulnerable eggs are hatching and fry are emerging.”
Brook trout may evolve, if given enough time, to adapt to these changing conditions. Unfortunately, these changes may outpace this kind of evolution.
