The black footed ferret is a member of the mustelid, or weasel, family. Although it is obviously not a squirrel, its survival depends on the survival of a ground squirrel, specifically the prairie dog. Up to 90 percent of this ferret's diet consists of prairie dogs. As farmers and ranchers exterminated the prairie dog from most of its native range during the twentieth century, the black-footed ferret was driven to the brink of extinction. With conservation efforts now underway, it is only just beginning to show signs of recovery.
Historically, the black-footed ferret could be found from southern Alberta and Saskatchewan, south to Texas, New Mexico, and Arizona, a range that correlated closely with that of the black-tailed, white-tailed, and Gunnison's prairie dogs. The ferrets are 18-24 inches long, including the six-inch tail, and weigh about two and a half pounds. They are territorial, and solitary except when mating and raising young. They are nocturnal, hunting at night for sleeping prairie dogs which they take from the burrows. In addition to eating prairie dogs, black-footed ferrets are one of several species that make their homes and raise their young in abandoned prairie dog burrows.
The nationwide effort to eradicate prairie dogs from farm and ranch land, which started in the early 1900s, was devastating not only to the prairie dog but also to the black-footed ferret. By the 1970s, the ferret was widely believed to be extinct. In 1981 a wild population was discovered on a private ranch in Meeteetse, Wyoming, and a subsequent search for survivors by the US Fish and Wildlife Service found around 100 ferrets. When an outbreak of disease reduced this population to only 18 individuals, the remaining ferrets were trapped for captive breeding.
Since then, breeding and reintroduction efforts have had some success. As of 2007 there were estimated to be around 650 black-footed ferrets living in the wild. Populations have been introduced in several states, including Wyoming, South Dakota, Montana, Arizona, Colorado, and Utah, as well as Saskatchewan in Canada and Chihuahua, Mexico.
However, in order for the black-footed ferret to survive in the long term, it is vital that the populations of prairie dogs on which they depend also be protected. One way that you can help is by signing this petition asking the state of South Dakota not to poison prairie dogs. The practice of poisoning prairie dogs is especially destructive because when ferrets eat the poisoned animals, they are, of course, eating the powerful poison as well.
The relationship between the black-footed ferret and the prairie dog is just one powerful example of how the removal of one species can affect others, and how easily an ecosystem like the plains/prairie system can be damaged by short-sighted actions like waging war against a species.