Plague Threatens Prairie Dogs — and the Ferrets That Eat Them

WALL, S.D. - A plague outbreak spreading through prairie dog colonies in the West is threatening a fragile conservation success: the black-footed ferret, America's most endangered mammal, which dines almost exclusively on prairie dogs.

The plague — the same Yersinia bacterium that devastated medieval Europe — arrived in North America a century ago and periodically burns through prairie dog towns, killing entire colonies within weeks.

Wildlife crews are dusting burrows with insecticide to kill the fleas that carry the disease, a laborious defense mounted across hundreds of square miles of grassland in South Dakota's Conata Basin.

The black-footed ferret was declared extinct in 1979, rediscovered on a Wyoming ranch in 1981, and rebuilt from 18 survivors to roughly 1,000 animals in the wild. The ferrets live in prairie dog burrows and cannot survive without them.

"Save the prairie dog and you save the ferret, the burrowing owl, the swift fox — the whole town," a Fish and Wildlife Service biologist said. "Lose the dog town and you lose it all."

___

Associated Press writers contributed to this report.

RECOMMEND THIS STORY