The United States is home to 416 mammal species and about 9 percent of the world’s total, placing us sixth among nations in mammal diversity. Currently 83 mammals are listed under the Endangered Species Act as either threatened or endangered. One-fifth of the U.S. mammals on the list of endangered species are bats, which may surprise many, but not when you consider the fact that bats (order Chiroptera) also represent approximately one-fifth of mammal species worldwide. 

Some of the mammals on the list of endangered species are considered genetically distinct sub-species of more common animals such as the Key deer and Florida Panther. Others receive the legal protection under the Endangered Species Act only in portions of their historic range where they may have become threatened. Good examples would be the grizzly bear and grey wolf in the lower 48 states, whose populations in Alaska are considered relatively secure. 

Among the rarest mammals not only in the United States, but North America as well, is the black-footed ferret. A distinct species exceedingly rare throughout its range, this animal was feared extinct until a small population was discovered in 1981 in Meeteetse, Wyo. Following a disease outbreak, the remaining 18 animals were placed in a captive breeding program.

From these lone survivors, more than 2,700 offspring have been re-introduced into the wild. The U.S. Fish and Wildlife Service estimates that there are over 650 individuals surviving in the wild, with a goal of 1,500 breeding adult ferrets in 10 locations to allow for down-listing from “endangered” to “threatened.” 

So far, re-introductions have taken place in 12 locations with the latest occurring in Kansas in December 2007. 

Visit the following Web sites for more information about endangered species or black-footed ferrets.

Fish and Wildlife Service 

Black-footed Ferret recovery program

Nature Conservancy, Kansas chapter