Beavers may be good where drought looms
By Jim Robbins, New York Times
BUTTE, Mont. — Once routinely trapped and shot as varmints, their dams obliterated by dynamite and bulldozers, beavers are getting new respect these days. Across the West, they are being welcomed into the landscape as a defense against the withering effects of a warmer and drier climate.
Beaver dams, it turns out, have beneficial effects that can’t easily be replicated in other ways. They raise the water table alongside a stream, aiding the growth of trees and plants that stabilize the banks and prevent erosion. They improve fish and wildlife habitat and promote new, rich soil.
And perhaps most important in the West, beaver dams do what all dams do: hold back water that would otherwise drain away.
“People realize that if we don’t have a way to store water that’s not so expensive, we’re going to be up a creek, a dry creek,” said Jeff Burrell, a scientist with the Wildlife Conservation Society in Bozeman, Mont. “We’ve lost a lot with beavers not on the landscape.”
For thousands of years, beavers, which numbered in the tens of millions in North America, were an integral part of the hydrological system. “The valleys were filled with dams, as many as one every hundred yards,” Mr. Burrell said. “They were pretty much continuous wetlands.”