The Black-footed Ferret
The story of the black-footed ferret's recovery should inspire all people who seek to prevent extinction of threatened species. Once thought to be extinct, a colony was found in the wild and with captive breeding, new wild colonies are being established.
Ferrets are members of the weasel family, so they are related to otters, badgers, mink and wolverines. The black-footed ferret is the only ferret native to the Americas. Domestic ferrets are descended from the European polecat rather than the black-footed ferret.
Studies have shown that prairie dogs make up to 90% of the black-footed ferret's diet. Fortunately for the ferrets, the North American prairie dog population may have been over one billion before the arrival of Europeans. Not surprisingly, their historical range closely matched that of the prairie dog, occupying prairies from Canada to Mexico.
Black-footed ferrets are nocturnal, so they were never seen frequently. They were first described by the naturalists John James Audubon and John Bachmann in 1851. They devoted three pages to it in their The Quadrupeds of North America. They never saw a live animal, but examined a poorly preserved specimen. Therefore most of their writing describes its physical appearance. Oddly enough, when they describe its prey, there is no mention of prairie dogs.
No further mention of the black-footed ferret can be found in writing until the 1877 publication of Fur-bearing Animals: A Monograph of North American Mustelidae by Elliott Coues. He refers to the animal as the "American ferret" as well as the black-footed ferret.
Prairie Dog Decline
When settlers came to the Great Plains, they plowed up the prairie so it could be farmed. Today, only about one percent of the original prairie has been left undisturbed. Prairie dogs were viewed as pests which needed to be eliminated. In the early twentieth century prairie dogs were widely poisoned. Even today, some poisoning of prairie dogs continues.
Sylvatic Plague came to America from Asia in the early twentieth century, and began to spread across the country. It decimated the prairie dog populations and was always 100% fatal to black-footed ferrets that contracted it. Canine distemper is also deadly to ferrets, although it does not affect prairie dogs.
Because of these factors, black-footed ferret populations plummeted. By the 1950s it was thought that they might even be extinct.
Back from Extinction
In 1964 a colony of black-footed ferrets was found in Mellette County, South Dakota. Ninety widely scattered ferrets were found, These were thought to be only ones left in the world. The animals were studied extensively, but in 1971 it became obvious the population was declining. In 1971 six ferrets were trapped to begin captive breeding. Four of these specimens died after receiving canine distemper vaccines. Over the next three years, three more ferrets were obtained. One litter was born in 1976 and another one in 1977. Unfortunately, none of the ten kits survived. In 1978 the U.S. Fish and Wildlife Service approved its Black-Footed Ferret Recovery Plan. There was just one problem - In 1979 their last captive ferret died, and the last wild ferret from the South Dakota population had died in 1974. Once again, it appeared that the black-footed ferret was extinct.
It might have stayed that way if not for a ranch dog named Shep. On September 26, 1981 he dropped an animal on the porch of his owners, who lived in Meeteetse, Wyoming. They didn't know what it was, but decided to have it stuffed, so they took it to the local taxidermist. The taxidermist took it, and made a phone call. He then returned to tell them that it was a black-footed ferret and he was required by law to confiscate it.
Personnel from the Wyoming Fish & Game Department quickly located the colony. They studied it closely, and their population peaked at 129 in 1984. In 1985 they found fleas in the area which had sylvatic plague. Because of this, they decided to start trapping animals. The first six that were trapped all died from canine distemper. By 1987, they had been able to obtain 11 males and 7 females, before the colony died out. Fortunately, 1987 also saw the first captive births with surviving kits.
By 1991 the breeding program had been successful enough that 49 ferrets were reintroduced into the Shirley Basin area of Wyoming. The following year kits were born in the wild. Today there are an estimated 500 black-footed ferrets in the wild, at 21 different re-introduction sites. Their recovery is still threatened by the possibility of disease outbreaks, and finding suitable re-introduction sites is a challenge. Nevertheless, their future looks brighter than it has in many years. If not for Shep the ranch dog, the black-footed ferret might have gone extinct.
- Saving the Black-Footed Ferret
- Phoenix Zoo Black-footed ferret web cam Live Streaming Video
- Black-footed ferret - Wikipedia
- Video 1 - A History of Black-Footed Ferrets - Wyoming Fish & Game Department
- Video 2 - Black-Footed Ferrets: The Rediscovery - Wyoming Fish & Game Department
- Video 3 - Black-Footed Ferrets: Captive Breeding - Wyoming Game & Fish Department
- Video 4 - Black-footed Ferrets: Reintroduction Program - KTWU