Black Footed Ferrets Still Struggling
One of the most endangered species in the Western United States, if not the entire country, is the black-footed ferret. In fact, it was listed as an endangered species in 1967, six years before the Endangered Species Act was passed by Congress. Today, more than 50 years on, this cousin to the weasel continues to struggle, and the U.S. Forest Service appears to be making things worse.
For a while after it was designated “endangered” it was thought that the black-footed ferret had actually gone extinct. And then, in 1981, a ranch dog in Meeteetse, Wyoming — “Shep” — came trotting home with a critter in it mouth, and it was determined to be a black-footed ferret, aka the prairie dog hunter.
Wildlife biologists were understandably thrilled by this find, and headed out and found a small population of black-footed ferrets. Zoom forward to 2020, and there has been an active captive breeding program through the U.S. Fish and Wildlife Service and the Wyoming Game and Fish Department that has led to some fairly good success with generating ferret populations to distribute in the West. And yet, the species is struggling.
“A lot of these (repopulation) sites are like five, ten, maybe 20 (ferrets), all adding up to 350, but even then, it’s been really challenging to build up their numbers,” said Chamois Andersen, the Rockies and Plains senior representative for Defenders of Wildlife. “We’ve got about 300 in captivity. So this is at the Fish and Wildlife Service center in Fort Collins (Colorado) as well as zoos. And those are the animals that we use to supplement the wild populations.
“And some of the wild populations are starting to have babies on their own, we’re starting to see recruitment happen,” she added last week during a call from her Laramie, Wyoming, office. “But not to the extent that we’d like to see for overall recovery.”
Key to the struggle is that 97 percent of the historic habitat of black-tailed prairie dogs, which ferrets prey on, has been lost. Finding, and maintaining, suitable habitat has been a struggle almost since Shep’s find launched a captive breeding program. Since the recovery program began in 1987 in a small Wyoming Game and Fish Department complex in remote Sybille Canyon, it has led to ferrets being released at about 30 sites in 16 states. Among those release points are Badlands and Wind Cave national parks in South Dakota.
At Badlands, where the program crosses over into the Conata Basin in Buffalo Gap National Grassland, ferrets are doing quite well.
“About 100 black-footed ferrets are at Badlands, 13,000 acres, it’s a model site for ferret recovery,” Andersen said. “But it took us ten years to get there. We went through plague, there’s been a lot of effort to get where we’re at with the successful ferret recovery, including $200,000 a year in investments.”
Wind Cave, while it has a surviving ferret population, it has not taken off like that at Badlands. There might be a couple dozen ferrets alive there, she said.
In looking around the West for possible release sites, a 50,000-acre site in Thunder Basin National Grassland in Wyoming had looked promising, in large part because of both the size of the site and its resident population of prairie dogs. However, in mid-May the Forest Service finalized an amendment to the 547,499-acre grassland’s management plan that allows for the killing of black-tailed prairie dogs that reside in the area and removes the designation of the area as a ferret recovery zone, according to Defenders.
The changes make it impossible for the area to support 100 breeding adult ferrets, which is a threshold that must be reached in ten of the 30 recovery areas for the “endangered” status to be removed from the species.
Thunder Basin “has been identified, because it’s a national grassland with such vast public lands, as a key site for ferret recovery,” Andersen said. “For many years we’ve been trying to overcome what has become a rather intense social issue with the local ranchers, landowners, in the region. It’s about prairie dogs. Ranchers tend to think prairie dogs eat all their grass for cattle, and would just as soon poison them all, including on our public lands, where they lease grazing rights.
“We’ve been trying to establish enough prairie dog acres and conserve acres for the reintroduction of the ferret and have yet to get past the social issue with the ranchers.”
Anyone who has been to Theodore Roosevelt National Park in North Dakota probably would think it might be a good recovery site for ferrets due to the readily apparent prairie dogs, but for now the focus is on maintaining and building the populations on the existing recovery sites, she said.
“And we’re not doing so well, to be quite honest. We have been sort of vacillating between 300 and 400 wild ferrets for the last several years, and can’t seem to get past that 400 mark of recruitment, of pups born in the wild every year,” Andersen added. “Primarily because prairie dogs on a lot of these sites, on adjoining lands, routinely get poisoned, so lethal control measures by counties and even ranchers and even federal officials, and then they’re also susceptible to sylvatic plague, and that can wipe out a prairie dog community in a matter of days, and ultimately, shortly thereafter we see black-footed ferrets quickly decline.”
More recently, another threat to the ferrets has cropped up: Covid-19.
“Obviously, it goes without stating that Covid-19 and the worldwide pandemic has had some serious implications for human health, and our attempts to control the virus has seriously disrupted our normal way of life and work. And on the work side, this includes the field work of wildlife professionals such as myself. When it comes to ferrets, humans can transmit the disease to ferrets,” the Defenders representative said.
“It’s a species of the mustiled family, which in domestic ferrets and minks has shown that they are susceptible to Covid-19 from humans, and they can also shed the virus back to humans. And so you can imagine, every year we are working so hard to maintain and even build up the wild population, and so if we in any way introduce this virus to ferrets, it could have dire consequences for overall recovery of the species.”
To guard against transmitting the disease to black-footed ferrets, biologists and technicians involved in the captive breeding and release programs all wear personal protective equipment when they are around the animals, she said.
“We’ve had numerous meetings over the last several weeks to come up with best management practices for just what to do to avoid and to minimize any risk for ferrets receiving this virus,” said Andersen.
The effort to help black-footed ferrets one day escape the Endangered Species List could use a little help from some of the public land-management agencies, too.