The endangered Black-footed ferret belongs to the weasel family and is the only ferret that is native to North America. Domestic ferrets are a different species and of European origin. The Black-footed ferret was once found in the tens of thousands, however, by the 1960s they were almost extinct. Although still endangered, the species is on its way to making a comeback. Concerted efforts over the last thirty years from many federal and state agencies, Native American tribes, private landowners, zoos, and conservation organizations have assisted in the survival of Black-footed ferrets.
Once common across the Great Plains from Alberta, Canada to the southwestern USA, by 1987, the Black-footed ferret in the wild was extinct. Today, following huge conservation efforts, reintroduced populations inhabit eight western states and Chihuahua in Mexico. However, of these, only three: one in Wyoming and two in South Dakota, are considered self-sustaining. These animals are found in the middle or short grass prairies and rolling hills in North America.
This species is active mostly at night, peak hours being around dusk. Ferrets reduce their level of activity in winter, sometimes staying underground for as long as a week. They are a subterranean species that uses abandoned prairie dog burrows for shelter and travel. Black-footed ferrets are solitary, except in the breeding season, with no male participation in raising the young. They are territorial, actively defending their territories against other same-gender competitors. These mammals are considered to be alert, agile, and curious, with a keen sense of sight, hearing and smell. Olfactory communication (defecation and urination) is used to maintain their hierarchies of dominance and to assist in retracing tracks when traveling at night. These are vocal animals that in the wild hiss and chatter when scared or frightened.
Black-footed ferrets are thought to be polygynous, based on information collected from skewed sex ratios, sexual dimorphism and home range sizes. This means that one male mates with multiple females. The breeding season usually is during March and April. This species exhibits "delayed implantation," where a fertilized egg does not begin to develop until conditions are right for gestation, the period of gestation lasting 35-45 days. Litters number 1-6 young, the average size being 3-4. Young remain in their burrows for about 6 weeks (42 days) before coming above ground. In July and August (the summer months) females and their offspring stay together; in the autumn they separate, the young ferrets having reached their independence. They become mature when they are one year old.
The Black-footed ferret population fell drastically in the earlier half of the 20th century, mainly due to habitat loss. Currently, habitat loss and introduced disease are key threats to this species. The ferrets are entirely dependent on prairie colonies for shelter, food, and raising young. Without sufficient reintroduction sites and protection against plague, recovery for this species remains difficult.
According to the Defenders of Wildlife resource, there are approximately 300 Black-footed ferrets in total living in the wild, and another 300 ferrets living in captive breeding facilities as of 2016. According to the IUCN Red List, the total Black-footed ferret population size is approximately 500 wild-living (released or wild born) individuals exist in populations in several US states and Mexico. Of these, 206 mature individuals occur in self-sustaining free-living populations. Overall, currently Black-footed ferrets are classified as Endangered (EN) on the IUCN Red List and their numbers today are decreasing.
Black-footed ferrets are important members of the ecosystem, both as predators, mainly of prairie dogs, thus controlling their populations, and as prey for their natural predators.