Swift fox reintroduction to area a success

The reintroduction of swift foxes to this part of north-central Montana appears to be a success in it's early stages.

Fort Belknap Indian Reservation, working in a cooperative effort with multiple state, educational and conservation entities, is reintroducing the swift fox to grassland areas of the reservation.

The diminutive, gray and gold fox is native to the area but its numbers sharply declined in the early 1900s and it was declared extinct in Montana in 1967. In addition to building on other efforts to bring back populations in Montana and southern Canada, this reintroduction will help efforts to bridge the gap between two separated populations by extending the northern population's range further south toward Wyoming and South Dakota.

"We didn't find any (swift fox) in this area, kind of a large area between the Milk River and the Missouri River - a pretty good chunk of the state," Fort Belknap Fish and Wildlife Department Biologist Tim Vosburgh said.

But the Fort Belknap Indian Community is working with diverse entities - such as Fort Belknap Fish and Wildlife Department, Montana Fish, Wildlife and Parks, Smithsonian Institution, World Wildlife Federation, Defenders of Wildlife, Calgary Zoo, which had assisted with swift fox reintroduction in Canada, and different entities in the three states which will be providing foxes for the program, Wyoming, Colorado and Kansas - to reintroduce the swift fox, as they did the endangered black-footed ferret, to the area.

"These are big undertakings and it just shows commitment and vision and dreaming of what was and making a reality out of it, and it's just been a pleasure," Hila Shamon, a research ecologist with Smithsonian Conservation Biology Institute, said about working with the Fort Belknap Indian Community. " ... It's just important to note that there's a whole community behind these projects."

The swift fox is about the size of a domestic cat, weighing in at 5 pounds with the males being larger than females. They are about one-fifth the size of a coyote and half the size of a red fox, with coloration more similar to the coyote than the red fox.

The Montana Field Guide describes the swift fox as "dark buffy-gray above, and orange-tan on the sides, legs, and lower surface of the tail (in winter). The chest and belly are buff to white and the tail is tipped with black. In summer the coat is shorter, harsher and more reddish."

The black tip on the tail is the distinguishing characteristic from other canid species in the area, along with their small size, which also makes them vulnerable to predation from coyotes and large raptors, the field guide says.

They also come by their name honestly, being able to reach speeds greater than 30 mph and to range over several square miles in a single night. This speed and stamina are displayed in an animal that is about 12 inches tall, with a length of the head and body at 15 to 21 inches and tail length 9 to 13 inches.

Background

While the historic range of the swift fox basically covered the Great Plains from Texas north into Alberta, Saskatchewan and Manitoba, extirpation of the swift fox came due to loss of habitat from farming and collateral damage from efforts to trap, poison and otherwise eliminate coyotes, prairie dogs and wolves. The swift fox range at its lowest was reduced to the western edge of the Great Plains from the very northern Texas to Wyoming and South Dakota.

The swift fox was also declared extinct in Canada in 1973, but reintroduction efforts started in Alberta and Saskatchewan in the early in 1980s near the border with the U.S. Many of those animals migrated into north-central Montana. Blackfeet Indian Reservation built on that success with a five-year reintroduction program that started in 1998, and Fort Peck Indian Reservation followed suit starting in 2006.

The swift fox reintroduction program on Fort Belknap, which is starting into its third of fire years, is intended to expand these efforts further.

"It's cool biologically, because they've been gone from this area for about 50 years and they have been successfully reintroduced to northern Montana and Canada. But despite that successful reintroduction, there's still that gap ... between the border and where they live in Wyoming and South Dakota," said Dana Nelson, a Clemson University student who is working on her Ph.D. on the swift fox and is working as a fellow with the Smithsonian Institution.

A true omnivore, the swift fox feeds primarily on small mammals, including mice, voles, Richardson's ground squirrels, jackrabbits and cottontails, as well as insects, small birds and plants. And breeding pairs have a range of 2,500 acres to 10,000 acres, Nelson said, though the larger ranges are only seen with the northern population.

They use burrows for shelter for their kits and when they are inactive. Though they will dig burrows for themselves, they also will take over burrows abandoned by prairie dogs, marmots and badgers.

The swift fox' willingness to use another animal's burrow helps with the reintroduction process called a soft release.

The foxes to be translocated are caught in stable, wild populations, checked medically, quarantined, then transported to their new location - a pen surrounding a prairie dog burrow - where they are held for a few days before release into the wild again, Vosburgh said.

"We put them into wire mesh pens, basically just chicken wire pens, that hold them for three to five days," he added, and even in the wild "that's generally where they hang out a lot of time is in a burrow to escape predation and get out of the elements."

The swift foxes are fed and watered while held in the soft release pens to be given time to acclimate and calm down after being being caught and transported for hundreds of miles, he said.

The initial 27 swift foxes released in 2020 came from Wyoming and in 2021 30 came from Colorado and another 18 were translocated from a different population in Wyoming, said Shamon, lead researcher with the project since the initial stages.

Shamon added that before taking any steps toward translocating any animals, extensive research and planning was completed starting with discussions in 2018 followed by an extensive two-year feasibility assessment of the habitat of Fort Belknap and surrounding areas.

It was a given that the swift fox would take to the short grass prairie and rolling hills that are in abundance on Fort Belknap, she said, but the area had other criteria to meet before this project could move forward.

Researchers did extensive soil studies to make sure the soil would support the needed burrows, or dens, and they surveyed rodents using traps to make sure the area would meet dietary needs, she said. They also studied coyote density by setting up camera traps in hundreds of locations "to make sure that the density was not too high - because we know that there is a competition between coyotes and swift foxes.

"Really, what we learned is that densities are pretty much, in terms of occupancy, pretty much equal across the region, not only on Fort Belknap but also in Phillips County and Valley County as well," she said, adding that "animals don't know human boundaries, so we knew some of them would go off the reservation and come back. We just wanted to make sure there was also suitable habitat on the peripheries."

With all boxes checked they programmed models - different simulations or scenarios - to show which places were suitable and not suitable on Fort Belknap and in the peripheries to determine factors such as locations for releases and annual numbers to be released to insure success of this population 50 years into the future.

Shamon said that the swift fox working group - composed of representatives from all the collaborating entities - decided to try for maximum success by introducing about 40 swift foxes each year for five years, which the models calculate will give them a 90 percent or higher chance of long-term success.

Data

Shamon said that when the swift foxes are first caught in their original populations, among the medical and physical information collected about the animals, researchers collect scat samples which they analyze for DNA, diet composition and, importantly, hormone levels which are stress indicators.

"We know that not everybody is going to survive. In natural populations about 40 percent of juveniles will die in the first two years of their lives, so the mortality is high anyway (and stress of translocation adds to the trouble)," she said.

Shamon and Nelson said their numbers so far are as good as or better than among established populations.

Different times each year after the animals are reintroduced, starting with samples collected from the soft release pens, their scat is collected and analyzed for those three indicators, she added. These tell researchers about the health and success level of the animals.

"Are they eating well, are they feeling well and who are they?" she said about the information.

They build a pedigree of offspring and track population growth.

The scat is collected at camera traps, a grid of hundreds of cameras set up on the reservation and surrounding lands. The swift foxes are baited in with scent stations, and motion sensors take a photo of the animals, which almost always leave a scat specimen as a way to do their own scent marking.

Even if a fox doesn't leave scat, the photos give some indication of the animal's physical condition, and the photo will show if the animal is one of the translocated "founders" or an offspring without a camera, Shamon said.

"There's a lot of monitoring," she added.

The GPS collars which are put on every swift fox reintroduced through the program provide location and travel data for up to a year. She said they currently have about 20 collars working.

Data gathered from these sources, as well as such things as best practices on reintroduction, will be shared in scientific publications and kept public as a resource for future efforts, said Nelson.

Shamon also said that students at Aaniiih Nakoda College on Fort Belknap will be helping with the project starting this year through classes, internships and fellowships.

Vosburgh said that the community has also been helping with tracking swift fox movement and possible den sites, with at least 12 reports of sightings in the program's first two years. But everyone can help with the project when they are in the Fort Belknap area.

"We're asking community members and anybody in the public that spots a swift fox to give us a call and hopefully get a location of where they saw it," Vosburgh said.

This is especially important in the springtime when the foxes are actually in dens and having the pups, sightings could give researchers clues for finding dens, monitoring the population and setting up a scent stations to collect data.

People can report swift fox sightings by contacting Vosburgh at 406-353-4801.

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See a video of swift foxes on Fort Belknap Indian Reservation at https://nationalzoo.si.edu/news/tribes-begin-five-year-swift-fox-reintroduction-fort-belknap .