SW Alaska News

University-Ak Fairbanks Center issued the following announcement on March 12.

The retreat of glaciers in western North America will lead to positive and negative changes for Pacific salmon, a multidisciplinary team of scientists reported on March 11 in the journal Bioscience.

University of Alaska Fairbanks associate professor Anne Beaudreau, a co-author of the paper, said it’s important to analyze the relationship between salmon and glaciers.

“Glaciers are melting and retreating at really fast rates. Ninety-five percent of Alaska glaciers are retreating, and that’s dramatically changing habitats for salmon,” Beaudreau said. “Glaciers throughout the range of Pacific salmon are expected to lose as much as 80 percent of their ice volume by 2100.”

This is the first study to look at the entire distribution of Pacific salmon and directly connect physical changes from glaciers melting and retreating with the future of the several species.

“As we started to dig into it, we realized that this is a hugely complex subject,” Beaudreau said. “People want to know if glaciers melting will be good or bad for salmon. It’s not so easy to say. There are conditions that will benefit salmon and there are conditions that will make their habitat less hospitable.”

The impacts will vary depending on the phase of glacial retreat, the species of salmon, the specific characteristics of different watersheds and the life stage of the fish.

For example, glaciers in parts of Glacier Bay, Alaska, are in the early stages of retreat on a geological time scale, and many now terminate on land. The edge of the ice is scouring out new river channels, which will open up more salmon habitat. In the second phase of retreat, the river channel becomes more stable and cool glacial water could buffer warmer waters in nonglacial tributaries.

Original source can be found here.

Source: University-Ak Fairbanks Center