The black-footed ferret is an example of a species that benefits from strong reproductive science. A captive-breeding program was initiated in 1987, capturing 18 living individuals and using artificial insemination. This is one of the first examples of assisted reproduction contributing to conservation of an endangered species in nature. The U.S. Fish and Wildlife Service, state and tribal agencies, private landowners, conservation groups, and North American zoos have actively reintroduced ferrets back into the wild since 1991. Beginning in Shirley Basin in Eastern Wyoming, reintroduction expanded to Montana, 6 sites in South Dakota in 1994, Arizona, Utah, Colorado, Saskatchewan, Canada and Chihuahua, Mexico. The Toronto Zoo has bred hundreds, most of which were released into the wild. Several episodes of Zoo Diaries show aspects of the tightly controlled breeding. In May 2000, the Canadian Species at Risk Act listed the black-footed ferret as being an extirpated species in Canada. A population of 35 animals was released into Grasslands National Park in southern Saskatchewan on October 2, 2009, and a litter of newborn kits was observed in July 2010. Reintroduction sites have experienced multiple years of reproduction from released individuals.
