Researchers Placed 76 Fake Beaver Dams in a Dying River — Then the Beavers Too

In 2009, a research team waded into a dying river in the Oregon high desert and did something no one had tried at this scale. They drove wooden posts into the gravel and built 76 fake beaver dams, flimsy imitations, without adding a single live beaver. Bridge Creek had cut itself into a scoured trench, too warm to keep its own fish alive, and the few beavers trapped inside it had been losing to it for decades. The plan was almost absurdly simple: fool the river, then step back. What the beavers did over the next four years is something no engineer predicted.