Do you know North America's rarest mammal? Meet the black-footed ferret (Mustela nigripes), a nocturnal carnivore about the size of a mink. They prey almost entirely on prairie dogs, and prairie dog declines nearly caused the ferrets’ extinction in the 1980s. All black-footed ferrets today descended from seven wild ferrets bred in captivity. Although captive breeding has been a success, disease outbreaks in the wild hamper their recovery. As of 2015, there were about 295 wild-born mature ferrets distributed among several re-established populations located in western states.
Photo: National Park Service