There are three main fret species in the world. The black footed fret (mustela nigripes) is among them. This fret is the only native fret to North America. Ferrets belong to the Mustelidae family, which includes weasels, minks, skunks and others.
The black footed ferret's diet includes prairie dogs. When farmers poisoned the prairie dogs to protect their crops it also effected the ferrets. In 1970 these animals were thought to be extinct. However, a small group of them were found in Wyoming a while later.
There are about 700 black footed ferrets that live in the wild today.