ALASKA — Alaska is hotter than ever this summer, and the salmon are dying because of it.
CNN reports that large amounts of salmon are dying off in Alaska due to the unprecedented heat wave that gripped the state in July and caused water temperatures to reach up to 81.7 degrees Fahrenheit.
In a Twitter post, Yukon Inter-Tribal Fish Commission Director Stephanie Quinn-Davidson said she and other scientists counted 850 dead chum salmon when they checked a 200 mile stretch of river during a July expedition.
According to the Independent, it's normal for salmon to die off after they spawn. But since most of the dead fish were found with healthy eggs still in their bodies, scientists believed they died of heat stress before reaching their spawning grounds.
According to Sue Mauger, science director for the Cook Inletkeeper, fish can't get oxygen moving through their bellies in warm water.
Temperature can also affect metabolism and organ function, making the fish less able to fight off parasites and pathogens.
The Independent reports that scientists stopped seeing dead salmon as soon as the temperatures cooled back down.
According to CNN, extreme heat brought about by climate change isn't the only thing stressing North American salmon populations.
In southwestern Canada and Northwestern Washington, salmon are being threatened by overfishing. A mining project in Alaska that's no longer being opposed by the EPA could also devastate one of the world's most valuable wild salmon fisheries.
