Earth Almanac: July/August 2007

In summer young black-footed ferrets—apparently descended from Siberian polecats that crossed the Bering land bridge—venture outside their dens to play, arching their backs, wrestling, and hopping backward. Your chances of seeing this, North America’s rarest mammal, are virtually nil, but they wouldn’t have been great even before humans poisoned off most of its prey (prairie dogs) and replanted most of its short-grass-prairie habitat to alien grasses. So just knowing these mostly subterranean, mostly nocturnal animals are out there probably will have to be enough. And that’s a lot, because in 1979, when the last known ferret died in captivity, the species was presumed extinct.

Then, two years later, it was rediscovered by a Wyoming resident named Skip, who collected a specimen near his home in Meteetsee; Skip was a ranch dog. Since then, in one of the great success stories of the Endangered Species Act, captive-bred black-footed ferrets have been widely reintroduced in Arizona, Colorado, Montana, South Dakota, Utah, Wyoming, and Mexico. The estimated population in the wild is nearing 1,000. The species’ future has brightened with short-grass-prairie restoration and a scaling down of the war on prairie dogs.