Wyoming’s bighorn sheep are pressed by skiers
At present the bighorns’ only major threats are avalanches, and winter die-offs through disturbance, exposure, or starvation. In the mid 2000s biologists from the Game & Fish, Grand Teton National Park, and the Bridger Teton National Forest wanted to know how backcountry recreation affected the sheep. That brought about Courtemanch’s in-depth study of sheep winter range, seasonal movements, and a comparison with backcountry ski routes.
Starting in the late 1980s, Grand Teton National Park staff closed a ski route that disturbed bighorn sheep winter range. A subsequent Very High Frequency (VHF) radio collar study in the mid-1990s by GTNP biologists Steve Cain and Mason Reed led to additional seasonal closures of ski routes in the national park.
While the closures on Static Peak and Prospectors Mountain frustrated some local skiers at first, most have now accepted them because there are so many other places to ski. GTNP public relations officer Jackie Skaggs says those who break the closures usually don’t know they exist, or don’t know where they are in relation to the closure.
The closed areas aren’t marked on the ground, but skiers learn about them through a public relations campaign called "don’t poach the powder," with maps posted on websites for the Jackson Hole Conservation Alliance and the Teton Avalanche Center. The park occasionally investigates violations uncovered by observing ski tracks on closed faces, or through social media postings of skiers’ exploits. Skiing in a closure is punishable by a fine of up to $5,000, with a mandatory court appearance.
Jackson resident Reed Finlay has skied mountains on all sides of Jackson Hole since the early 1990s. Now a ski patroller with the Jackson Hole Mountain Resort, he says most skiers recognize the importance of the closures and have a respect for the sheep.
GTNP biologist Sarah Dewey, who worked closely with Courtemanch during the study, said the research confirms that existing closures have largely succeeded in protecting sheep habitat in Grand Teton National Park. The study identified further areas of the Tetons that sheep could be using in winter, but are avoiding.
Courtemanch collected data on skier routes by asking some 800 backcountry users to voluntarily wear a GPS device for the day. Many of the skiers who enter sheep winter range originate at just a few popular trailheads and at Jackson Hole Mountain Resort. When she mapped the skier data with the sheep data, the results suggested disturbance from skiers causes sheep to avoid a significant amount of otherwise ideal winter range.
It’s possible further winter closures on Bridger Teton National Forest could help take pressure off the sheep, though managers haven’t considered any yet. Kilpatrick pointed to Jensen Canyon as one area of possible discussion, where restricting travel to a single corridor could allow skiers to unobtrusively pass through sheep winter range.
Importantly, any future closures would not affect the vast majority of skiers, while leaving many other places to ski in the Tetons from December through March. The closed areas would remain open to late spring skiing in April and May.
"We have disease taken care of," Kilpatrick said. "The next topic is habitat. Let’s start with working with the backcountry users, and provide a little more habitat by restricting use." In addition, Kilpatrick said managers could use wild and prescribed fire to improve low elevation summer habitat on the west side of the Tetons.
Further discussion of management of the Teton sheep will wait until this fall, to give time for Courtemanch’s study to make it through the academic peer-review process. At that point the inter-agency Bighorn Sheep Working Group will meet to discuss the study and any potential policy changes on National Forest land. Any further closures would be considered in a public comment process, said Dale Dieter, district ranger with the Bridger-Teton National Forest.
While it remains to be seen what actions will be taken to preserve the sheep, it’s clear no one wants to see the herd decline or disappear.
"They are a signature species of the Tetons and I think there is a lot of interest in finding ways for them to persist," Whitfield said. "They are a population that has been in the Tetons for thousands and thousands of years, so we need to find a way to be compatible with them."
Finlay said it would be a terrible loss if bighorn sheep vanished from the Tetons. "To me they symbolize the high country," he said. "It would be like if the bald eagle disappeared."