Northern fish are tough, but climate change is causing some to dwindle
Our research team set out to see how stream fishes were responding to unprecedented environmental changes across their northern ranges. Ultimately, we wanted to know how these changes might affect the hundreds of thousands of people in Alaska and northern Canada that rely on local fisheries for food, culture and economic security.
Initially, we were surprised to learn that warming was increasing the distribution of cold-adapted fish. We reasoned that modest amounts of warming could lead to benefits such as increased food and winter habitat availability without reaching stressful levels for many species.
Yet, not all fish species fared equally well. Ecologically unique northern species — those that have evolved in colder, more nutrient-poor environments, such as Arctic grayling and Dolly Varden trout — were showing declines with warming.