A beaver is released on to a stretch of river in northern Washington that has been prepped for its arrival. Photograph: Morgan Heim Molly Alves steps down hard on the edge of a heavy wire trap, forcing its sides open with her hands. With care she lays the poised trap, baited with twigs and branches, in a bracingly cold stream. Her target? A beaver. Beavers are often considered “nuisance” animals on the US west coast and, if captured, are destroyed by animal control companies. But the beaver picked up by Alves is to be transported to Alves’ employers, the Tulalip Tribes, a nation in Washington’s western corner. This Native American community, and others, are at the vanguard of the “beaver believer” movement, which holds that the rodents can play an essential role in maintaining healthy landscapes.