Black-legged ferrets: the main milestones for a once presumed extinct species


The black-footed ferret, the only species of ferret native to North America, is said to have become extinct in 1979. On September 26, 1981, a black-footed ferret was discovered in the prairie of Wyoming. From this unlikely event, an entire species began its return – one of the most remarkable conservation stories on Earth. In honor of the 40th anniversary of the discovery of the last black-footed ferret colony, here are five of the important milestones in the conservation of this miraculous species.

  1. Discovery of a lost species
    In 1967, black-footed polecats were classified as endangered. By 1974 they had apparently disappeared from the wild, and by 1980 the last black-footed ferrets taken in by humans died, leaving the species extinct. In 1981, a ranch dog in Meeteetse, Wyoming named Shep brought home an animal that its owners, John and Lucille Hogg, did not recognize. On taking it to the local taxidermist, they discovered it was a black-footed ferret! Enthusiastic wildlife biologists searched the surrounding area for prairie dogs, the primary food source for ferrets in the wild, and found a black-footed ferret colony. The once presumed extinct species was back on the map.
  2. Ferrets taken care of by humans
    For several years, biologists monitored the last wild colony of black-footed ferrets. In 1985, fleas carrying the deadly sylvatic plague – which in humans is bubonic plague – were discovered in the colony. Due to the plague and the risk of canine distemper, the number of the last colony began to decline. As a result of intensive studies and discussions between scientists and wildlife experts, all black-footed ferrets were taken in by humans to create a breeding program and attempt to prevent extinction. The last wild ferret was captured in 1987, when only 18 ferrets made up the breeding population of the entire species: seven males and 11 females. That same year, two litters of ferrets were born at the Sybille Wildlife Research Center in Wyoming – the first surviving ferret kits born under human care. Managed by the Wyoming Game and Fish Department until 1996, the US Fish and Wildlife Service assumed oversight of operations in 1996 and established the National Black-footed Ferret Conservation Center.
  3. Smithsonian joins the ferret force
    In 1988, there were a number of surviving black-footed ferrets. The Smithsonian Conservation Biology Institute in Front Royal, Va., And the Henry Doorly Zoo in Omaha, Nebraska have joined the breeding program. The following year, six ferret kits were born at SCBI, the first ferrets born into human care outside of Wyoming. An ambitious black-footed ferret recovery plan was approved and adopted. The new plan called for strategic breeding and cryopreservation of black-footed ferret genetic material, including sperm, at the SCBI and the frozen zoo at the San Diego Zoo.
  4. Born to be wild (again)
    From 1988 to 1993, the Cheyenne Mountain Zoo, Louisville Zoological Gardens, Toronto Zoo, and Phoenix Zoo joined in black-footed ferret conservation and breeding efforts. As more kits were born, environmentalists began to think about reintroduction efforts. Environmentalists, veterinarians and scientists worked together to determine the best way to “precondition” ferrets born under human care to survive in the wild. Large enclosures were created to help ferrets learn to dig, trap and kill live prey – prairie dogs.

    In 1991, 49 ferrets were released into the wild in the Shirley Basin, Wyoming. In 1998, more ferret kits were born in the wild than in human care, and black-footed ferret colonies were established in several locations throughout the American West. Since the blackfoot breeding program began in 1986, more than 10,500 ferret kittens have been born under human care, including more than 1,000 at SCBI. Of the ferrets born at the Smithsonian, more than 350 have been released into the wild.

  5. Frozen Future: Scarface and Willa
    The last male black-footed ferret captured from the wild in 1987 was called Scarface. It has proven to be a lifeline for the species, spawning many healthy ferret kits. In 2009, Scarface made a big impact again. As the current black-footed ferret population is small, careful breeding is vital to maintaining healthy animals. Thanks to the foresight of the scientists who started the breeding program, including Dr JoGayle Howard and David Wildt of SCBI, frozen black-footed ferret semen has been set aside for the unknown future. In 2009, live and healthy kits were born as a result of an artificial semen from a female ferret using the frozen semen of 20-year-old Scarface. The ability to successfully artificially inseminate using frozen and thawed sperm has increased scientists’ ability to ensure a more diverse black-footed ferret population in human care and in reintroduced populations.

    Last year, using biomaterials and ingenuity, scientists were able to clone a female named Willa, one of the original 18 ferrets discovered who has no living descendants. Her clone, Elizabeth Ann, was born on December 10, 2020. For the first time, new black-footed ferret genes have been reintroduced into the species. Conservation innovations, like cloning, and ongoing breeding and reintroduction efforts help ensure the black-footed ferret continues to roam the North American prairie.


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