Thinking like beavers could help combat drought

For Idaho and other parts of the West fighting drought and arid conditions, taking a cue from beavers might help.

Though beavers are thought to be a nuisance by some landowners, researchers are finding the dams they build on creeks and rivers actually help restore them.

Researchers describe the process as “soaking the sponge,” as these structures increase water levels both above and below ground.

Damon Keen, a fisheries biologist with Idaho Department of Fish and Game, said so-called beaver mimicry structures have increased in popularity in eastern Idaho over the last decade as a way to restore fish habitat.

“You’re actually going in there and making beaver dams, and then hopefully by improving that habitat, backing up that water, you see more willow growth and hopefully, beavers do then move in there, in that improved habitat, and start working on their own,” Keen said.

The structures also help lower water temperatures and allow streams to flow longer without drying out.

Beavers were almost wiped out in the Northwest a century ago, but have made a comeback. In some cases, Idaho Fish and Game takes beavers from spots where they’re causing headaches for landowners and moves them to habitats in need of rehabilitation.

Much of the beaver mimicry work is going on at Idaho’s border with its Big Sky neighbor.

Nathan Korb, freshwater director of The Nature Conservancy of Montana, said drought is one of the biggest threats to humans and natural systems in this area, and climate change is exacerbating it.

“Anything that we can do to address drought or make people and nature more resilient to drought is going to be a good strategy, and this is one of our best strategies for dealing with the climate change effects,” he said.

Rebekah Levine, professor of environmental sciences at the University of Montana Western, also sees a lot of promise in mimicking beaver structures. She said people are moving toward a future where every drop of water will be more valuable.

“In a world where we’re going to be up against water resources limitations, we really need to be creative and try multiple different possible solutions,” she said. “And this is a really great idea, and we just need to keep testing it.”

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Eric Tegethoff writes for Public News Service in Boise.