he species declined throughout the 20th century, primarily as result of a decrease in prairie dogs — the ferrets' main prey — which were exterminated as agricultural pests. In 1979, black-footed ferrets were declared extinct, but in 1981, Lucille Hogg’s dog brought a dead one back to their Wyoming home, and scientists scrambled to find more, eventually locating a colony of 61 ferrets. Thanks to conservation efforts, about 1,000 of the animals are now thought to live across the central U.S.
Black-footed Ferret is categorised as Endangered because of its very small and restricted populations. As of early 2015, there are about 295 wild born mature individuals distributed among several re-established populations. Of these, 206 are in self-sustaining free-living populations.
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