Human-made beaver dams likely save natural wetland from extinction

A natural wetland in southeast Oregon was likely saved from extinction thanks to four years of collaboration and some human-made beaver dams.

In the Oregon high desert, about seven miles northeast of the town of Crane, Alder Creek bubbles to the surface surrounded by sagebrush and juniper trees.

The creek and wetland create an actual oasis in one of the driest and most remote sections of the state, said Ken Diebel with the Malheur Watershed Council, a chief BLM partner on the project.

“It’s really the only source of water out in a long way,” he said.

The Alder Creek headwaters, at about 5,000 feet elevation, is also almost at the top of the Malheur River watershed, making it a logical spot to focus on restoration work, said Diebel. “The things we do up there will benefit the entire watershed,” he said.

Back in 2015, when the restoration work began, the oasis was on the brink of disappearing.

Historic farming practices at the wetland changed the fundamental makeup of the landscape.

Instead of a deep meadow with soil that absorbed water and released it in the hot months, the wetland was shallow and water cascaded too quickly over numerous headcuts, or small waterfalls.

The approximately 40-acre meadow was potentially going to shrink to just a few acres, with encroaching Western juniper trees replacing elk, Columbia spotted frog, redband trout, and of course, beavers, among other native wildlife reliant on the spring.

“Really it was 99 percent about preventing the loss of the wetland,” said Lindsay Davies, the BLM fisheries biologist who helped manage the project.

It took hours to maneuver a small excavator into the area so larger scale repairs could be made to correct the grade of the waterway.

After that, structures made of wood and rock—including nine of those human-made beaver dams—were placed to trap sediment and slow the erosion that was taking place.

About a mile of willow trees were planted in the corridor, too, replacing juniper that were cut down.

Finally, the result last year was a transformed wetland corridor drastically lush and green compared to the surrounding desert.

“It’s amazing how green everything is and how much wetland – it’s a bigger wetland than we had originally anticipated,” said Davies.

Holistic watershed restoration on this scale takes a big team, said Davies, citing vital BLM partners like the Oregon Watershed Enhancement Board, Rocky Mountain Elk Foundation, and many others on the local, state and federal level.

And potentially the best part about the Alder Creek restoration: The work is designed to last 100 years, giving wildlife plenty of time to reestablish.

BLM wildlife biologist Travis Miller thinks beavers will have a better chance of escaping predation in the deeper water and have the potential for long-term habitat.

“It would be really good to see those populations rebound and establish in these systems,” said Miller.

Full list of project partners: Malheur County Watershed Council; Oregon Watershed Enhancement Board; Rocky Mountain Elk Foundation; Grant County Soil & Water Conservation District; U.S. Army Corps of Engineers, Headquarters; Burns Paiute Tribe; The Nature Conservancy; Oregon Department of Fish and Wildlife; adjacent private landowners; and grazing allotment permittees.