Trout habitat in Alberta dwindles as streams heat up: Yale Climate Connections

Bull trout, Athabasca rainbow trout, and Westslope cutthroat trout live in icy streams that flow down from the mountains of Alberta, Canada.

But as the climate warms, those streams are warming, too – causing these fish to retreat into the dwindling refuges of cold water upstream.

Kissinger: “As it warms downstream, it forces them further upstream into an ever-shrinking available amount of habitat.”

Ben Kissinger is a water and fish scientist with the fRI Research group.

He says the problem is made worse by the loss of many streamside trees and plants, which used to shade the water from the hot sun.

All three trout populations face other threats, too.

Kissinger: “If you have all those other threats like angling pressure and fragmentation and habitat loss on top of warming waters, that really makes it hard for these species to exist.”

So Kissinger is mapping water temperatures in Alberta’s streams to better understand how the trout’s habitat is changing.

He says it’s important to protect streamside vegetation and the remaining stretches of cold water.

Kissinger: “Those might be crucial refuges for these cold-water species as we move into a warming future.”

So Kissinger’s research could help these trout survive even as the climate continues to warm.

Reporting credit: Ethan Freedman / ChavoBart Digital Media