Lake trout. (Credit: Timothy Knepp / U.S. Fish and Wildlife Service)
Research carried out at Canada’s Experimental Lakes Area has found that lakes in the region have warmed by 0.4 degrees Celsius over each of the past five decades, according to TB NewsWatch. The effects of the higher temperatures have been felt by fish in the lakes.
Lake trout, in particular, seem to have gotten smaller thanks to the shift in temperatures. Scientists say that the average size of adults of the fish have gotten smaller over time. This trend is also showing up for other freshwater species that favor colder waters for spawning.
In addition, runoff from increasing summer rains is causing water discoloration, which affects the heat distribution of lakes and could be making the effects to lake trout worse. In some lakes, researchers have found that there are minimal depths, about a meter, that are comfortable for lake trout. This problem appears mostly in the fall period.
Top image: Lake trout. (Credit: Timothy Knepp / U.S. Fish and Wildlife Service)