In the next five years, Grand Teton National Park biologists may kill or remove more than 100 nonnative mountain goats that are quickly expanding and beginning to comingle with one of the most unique bighorn sheep herds in the West.
The decision to eliminate a charismatic creature wasn’t easy, said Grand Teton National Park biologist Sarah Dewey, but it was pretty clear.
Mountain goats aren’t native to the park or Wyoming, they wandered over from Idaho, where they’d been introduced in the late ‘60s and early ‘70s. The fragile and shrinking bighorn sheep herd has been there, genetically unchanged, for tens of thousands of years.
“The sheep are struggling, and this is kind of one more straw, and is it the straw that will break the camel’s back and send the herd into an irreversible decline? The trouble is, if that happens, we don’t get the sheep back,” Dewey said.
The issue between bighorn sheep and mountain goats are two-fold, said Dewey. The first problem is competition for habitat.
Goats had been moving slowly into Wyoming and closer to the park for years, but only recently have they begun to reproduce there, delivering twins and sometimes triplets each year.
While the vast corners of Grand Teton appear to offer abundant habitat, bighorn sheep and mountain goats generally live in the same high-mountain cliff bands and feed off of the same sparse vegetation, especially in the winter. A recent study showed that the park has enough annual habitat for up to 400 mountain goats. Some evidence also shows that mountain goats tend to be more aggressive than bighorn sheep.
The second, and potentially most concerning issue, is disease. The bighorn sheep herd – now numbering less than 100 – has lived at isolated elevations between 8,500 and 11,000 feet for thousands of years. Since the herd stopped migrating to lower elevations decades ago, it has been relatively cut off from possible diseases.
The encroaching mountain goats, however, have tested positive for pneumonia pathogens, the same ones that have wiped out bighorn sheep across the West.
“And so we feel like we need to try this, as well as a lot of other things, to shore up the fate of the sheep herd,” said Dewey. “And so yes, it is hard, it’s one of the more challenging kinds of resource problems that I’ve ever encountered.”
What, exactly, to do about the goats took the park years to decide. In December, Park Service officials announced a possible plan for the encroaching animals that included three options: do nothing, kill all of the goats or try to capture and relocate some and kill the rest.
The park’s preference is to use a combination of relocation and sharpshooters.
Only about 25 percent of the park’s 100 or so goats are likely to be captured for relocation. Capturing goats in the winter in the Tetons – which is the only option because it would be nearly impossible to capture wildlife in the summer when hundreds of thousands of visitors descend on the area – is tricky at best and dangerous at worst.
Park wildlife officials tried capturing goats and sheep for research for multiple days in December and only ended up with one goat and two sheep, Dewey said. Relocation also comes with the requirement that officials find somewhere that will take the invasive goats.
As a result, the Park Service’s plan calls for three-quarters of the goats to be killed by sharpshooter, likely from a helicopter.
The Wyoming Game and Fish Department, which manages the goats and sheep that wander outside of park boundaries, agrees with the plan, said Doug McWhirter, Game and Fish’s wildlife coordinator in Jackson.
Ideally, the department would like the park to either relocate all of the goats or allow some kind of hunting season, or use “skilled volunteers.”
But beginning a hunting season in a national park requires an act of Congress, and using skilled volunteers – essentially hunters who won’t plan to harvest any of the animal – would not be as efficient as trained shooters from aircraft, Dewey said.
The decision is a difficult one, said Chris Colligan, wildlife program coordinator with the Greater Yellowstone Coalition, but necessary. The coalition – a nonprofit group of wildlife advocates in northwest Wyoming – agrees that the park should use paid sharpshooters.
“From our perspective, we would like this to be a very expedited process,” Colligan said. “They’re very close to the brink right now, and I don’t think we have time to have a discussion on state versus federal rights.”
The plan, if approved, will already be delayed because of the recent government shutdown. Park Service officials had hoped to end the public comment period in early February and begin planning soon after with captures and sharp shooting beginning before spring. But when the public comment period, and associated work on the plan, was delayed, it will likely be late fall or early winter before they can begin. And every spring that passes means additional goats in the park and higher threats of disease.
“In 2013, when the park scoped the goat plan to the public, there were an estimated 15 goats in the park, now there’s 100-120 goats in the park,” said Steve Kilpatrick, executive director of the Wyoming Wild Sheep Foundation. “I’m not advocating this with a cold heart, it tugs at the heart, it hurts. But do we want to see the sheep blink out at the expense of an introduced exotic carrying diseases it has acquired?”
The park estimates it could take about five years before all of the goats are gone. Game and Fish, for its part, created two new mountain goat hunt areas near Grand Teton and Yellowstone national parks. In those areas, the department received legislative approval to deviate from Wyoming’s one-goat-license-per-lifetime rule. The effort is to try and ensure after the goats in the park are removed, no additional ones are allowed to enter, McWhirter said.
Goat populations in and around the Palisades and Bear Tooth Range will still be allowed to thrive under limited hunting seasons that protect their numbers, he said.
“It’s not that we’re anti-mountain goat,” McWhirter said. “It’s just in certain places, and in this place, we’re more pro-sheep.”