State and federal wildlife officials recently made what they hope is the last release of endangered black-footed ferrets in the Meeteetse area, introducing 13 captive-bred kits and one adult to the re-established population.
Last month’s release came amid continued good news about the recovery efforts.
For the second straight year, wildlife biologists have recorded new litters of wild-born kits in the area, located about 20 miles west of Meeteetse. The first known litter came in 2017, one year after reintroduction efforts began, and the recent findings were even better.
“This year, we had at least four litters,” said Dana Nelson, non-game biologist and lead for the state on the ferret program. Litters of kits are important because population size is the best way to rate reintroduction efforts, Nelson said.
The news energized those in attendance at the Sept. 28 release, but the event was much different from previous years. The first year, more than 100 people, including landowners and fans of the program, attended the release. The second year, a large party was thrown by the owners of the Pitchfork Ranch, recipients of a couple dozen ferrets. For last month’s release, only Hogg family members and a handful of scientists were present.
“We’re old pros now,” said Alan Hogg, co-owner of the Lazy BV Ranch. The historic ranch was the site where John and Lucille Hogg’s dog, Shep, brought in a black-footed ferret in 1981 after the species were declared extinct.
Despite crowd size, those in attendance witnessed the fall release on a gorgeous evening as brilliant colors from changing leaves accentuated the ceremony.
“When you’re on top of the plateau, it’s hard not to feel you’re somewhere magical,” Nelson said.
The Game and Fish team surveys the ferret population each summer. Since the feisty little critters are nocturnal, the surveys are done at night by flashlight. It’s arduous work that takes a couple weeks of long nights to accomplish. Twenty-one ferrets came through the processing trailer last summer, where they were given health check-ups and vaccinations against plague and canine distemper while having their demographic data recorded.
“This should be the last reintroduction as long as their population continues to look good,” Nelson said. “We’re thrilled to be further supplementing populations in areas where we have prairie dogs but not ferrets.”
Monitoring now becomes crucial, Nelson emphasized. In Wyoming’s first reintroduction site in the Shirley Basin, between Casper and Laramie, 228 black-footed ferrets were released between 1991 and 1994, but by 1997, the population had crashed. Surveys that year only found five ferrets remaining. Plans to release 19 more ferrets in Shirley Basin on Oct. 18 — 27 years after the first release — are a testament to both the long-term effort it requires to ensure the survival of the species in Wyoming and the difficult nature of the task.
Unlike the Meeteetse release sites, Shirley Basin is not currently being treated for sylvatic plague, Nelson said.
Sylvatic plague, carried by fleas, infects prairie dogs and can wipe out a colony. Black-footed ferrets rely on prairie dogs as their main food source and are susceptible to the highly communicable disease. Ferrets can be infected with plague by feeding on diseased prairie dogs, or by being bitten by fleas carried by their prey. Plague-carrying fleas are the No. 1 threat to the endangered species, whether they kill off their prey or infect them, said Zack Walker, Game and Fish non-game program supervisor.
“The most important issue is making sure the prey base is healthy,” Walker said.
About 70 percent of wild prairie dogs successfully ingested baits containing an oral sylvatic plague vaccine, or SPV, distributed throughout their habitats, according to a new U.S. Geological Survey study. The drug was deployed in Arizona, Colorado, Montana, South Dakota, Texas, Utah and Wyoming — all states with black-footed ferret release sites. A harmless dye was used in the peanut butter-flavored baits and, once ingested, is viewable under certain microscopes. Scientists sampled 7,820 prairie dogs for presence of the dye to determine which animals had eaten the bait.
The department continues to dust for fleas — currently using the insecticide Deltadust, or deltamethrin — on about 3,000 acres with sylvatic plague vaccine deployed on 1,000 acres of Bureau of Land Management and private lands at the Meeteetse release sites, Nelson said. Game and Fish will continue to monitor the Meeteetse population into the foreseeable future.
The goal for the Meeteetse population, known as a business, is nearing, said Nichole Bjornlie, non-game mammal biologist for the Game and Fish.
“The population goal of any viable population, according to recovery criteria, is a minimum of 30 breeding adults,” she said.
The 21 ferrets that were recaptured this summer were among 59 ferrets that had been released in the first two years of the local program. U.S. Fish and Wildlife official Kimberly Fraser said ferrets have spread well outside of the monitoring area.
“Ferrets have been known to move 10 miles in three days,” Fraser said.
The species grows quickly and develop their taste for their prey at a very young age; captive-born kits released can be as young as 2 months, Bjornlie said.
“These kits have all gone through conditioning and have proved they can kill a prairie dog,” said Bjornlie. Considered the rarest mammal in North America, all captive-bred ferrets are raised at the U.S. Fish and Wildlife Service National Black-footed Ferret Conservation Center near Ft. Collins, Colorado.
With more than 9,000 black-footed ferrets propagated from just 19 that were found surviving in the Meeteetse area 37 years ago, prospects look bright for the future of the species.
“Black-footed ferret recovery has provided predictable, incremental gains over the past few decades and is poised to reach its final goal with continued, focused efforts by its many supporters. While the road to recovery has been a long one — with twists and turns, a few detours, and some welcomed surprises — the recovery of this species could be just around the corner,” Pete Gober, black-footed ferret recovery coordinator for the Service, said in an essay about the species.