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2 ..'1.,.i. r. it*.. 'l$.1 ly back in the Tetons, at 10,000-feet, deep snow piles up in chutes and basins wind-blown ridgelines. rali herd of bighorn sheep spend nters on these ridges, foraging itde food exposed by the wind, ) save energ"y so they can live rfrfat reserves until spring. snt the case 70 plus years ago. r's thesis completed by Mihitfieid in 1983 at Idaho State,ry, documented a historic loss ofbighorn habitat quanriry and qualiry in the'tetons. Most notable was the ioss of low elevation winrer ranges and migration routes due to human development. Meanwhile in the nearby snowfilled chutes and basins, more and more backcouncry skiers are carving turns and also, according to a recent study, disturbing bighorn sheep already struggling to survive. "Years ago the sheep might have gone all winter without seeing any humans," said Alyson Courtemanch, the \Tyoming Game and Fish Department wildlife biologist for the area. "But now they run intl backcountry users who are inadvertently driving the animals from the little suitable habitat thev have in the winter." As a Universiry ofvyoming graduate student in 2008, Courtemanch studied the ecology of the herd, its wintering areas and the potential impacts of winrer backcountry uses on bighorns. The study was cooperarively designed by the universityt Vyoming Cooperative Research Unit, Grand Gton National Park, Bridger-Gton Nationaj Forest Service and the department. In 2008, 28 female sheep were fitted with giobal positioning system or GpS collars to track the animals' movements. During the winters of and GPS units were handed out at 1 1 popular backcountry ski trailheads to record where 260 skiers were making turns in the Tetons. Courtemanch and the research team wanted. A young bighorn trudges through deep snow. The intersection of recreation and winter range pose a chailenge for the ipecies in the Tetons. *o* i-ioror,u, \Wyoming \Tildlife I 39

3 iil to find out ifbighorn sheep avoided good habitat in an effort to avoid people. Researchers discovered bighorn sheep elicited a srronger response rhan anticipated. The animals showed strong avoidance ofareas skiers used, even if the area was excellent habitat and there were no other barriers or problems with the space. "And the bighorns avoided areas that were used byjust one skier or hundreds a day," Courtemanch added. Ungulates can get used to predictable disturbances, like cars on a road or even people on a trail, because their path is predictable. Itt when people leave designated trails rhat sheep become uncomfortable. "It creates a predator response in the sheep," Courtemanch said. "They dont know where or when a skier might pop up on the landscape so theyjust avoid the enrire area." Suitable bighorn habitat at 10,000 feet is scarce and patchy in the Tetons. \Vhen skiers enter bighorn sheep habitat, itt another space the sheep lose from an already small amount of winter range. People have already pushed bighorn sheep from their normal wintering habitat. "The Teton herd used to be migratory" Courtemanch said. "Every winter they came down from the mountains to weather the cold season in Teton Valley andjackson Hole." In the early 20th century as people began to permanently settle the valley, building roads, fences and houses, the sheep stopped their winter migration to lower elevations. They now winter at some of the highest elevations in the Tetons. "It's amazing this population has survived migration loss and contin- ued to persist," Courtemanch said. The herd has maintained a stable, but precarious, population ofabout 125 sheep. "But 125 sheep is very small," Courtemanch said. "As managers we are definitely concerned a bad winter, or disease, or generic inbreeding could, for such a small population, have a big impact.'we dont wanr any additional Even if violated by only one skier or snowboarder, research has shown bighorns will likely not return to the area. The Tetons beckon extreme recreation but also wildlife reveren(e. - Photo by Ma*Gocke stress on those sheep, especially during the winter." "Gton sheep have long survived a tenuous existence," said Steve Kilpatrick, director of the 'Wyoming Vild Sheep Foundation. fu a department habitat biologist in the mid-1980s, he and Vhitfield, a Caribou-Thrghee biologist, became involved with a working group for the herd and helped develop the "Strategic Pknfor Managing Bighorn Sheep in the Teton Range." "That herd has always been ofconcern because itt so small and restricted year-round to high elevarions," Kilpatrick said. "!7hen a herd is that small and confined, it can blink out pretty quickly." The plan's first priority was to minimize disease transmission, namely pneumonia, from domestic sheep. The foundation and odrer conservation groups worked with ranchers and the Caribou-Targhee National Foresr, providing economic incentives to grazing permittees to retire grazing allotments in the Teton Range. "\7ith the willingness of several ranchers, cooperation of the forest service and expense of several hundred thousand dollars, our first priority was achieved," Kilpatrick said. It is important to note that Courtemancht research showed the bighorns began to make additional use of the retired grazing allotments, he said. The research found that GPS-collared bighorns have started using the former grazing allotments, validating the importance of those areas for the Teton herd. The group was also concerned about genetics. Genetic tesring done by Grand Gton National Park and the University of Montana showed there are two genetically separate herds in the Gtons and that they have low genetic variation. "The lack of diversity in the gene pool suggests the animals may be less resistant ro disease," Kilpatrick said. \X/hile backcountry skiing wasnt as popular in the 1980s as it is today, the working group ralked about recre- 4O I January20l6 wgtd.wyo.gov

4 \,;;:1ffi. #"ih.."..,:'..:{{: '"6M *-kfr Itt-^r-,# -!, ni ^* ii.;-j photo by lt4ark Gocke ation.and its impact on bighorn sheep even back then. The study ollered an ovenriel of the herd, including rvhere it winrers. as well as rhe porenrial impacts of. backcounr ry winter recrear ion. In a rown like Jackson, there,s alwav.s been people headed ro find pou.der stashes in the backcountry, putting climbing skins on their skis so thei It's lrhen people leave designated trails that sheep become uncontfortable...it creal.es a predator response in the sheep,,'alyson Courtemanch, a \\.\ oning Game and Fish I)epartmenr rl ildli fe biologist saitl. can mo\re uphlll or carrying their gear while they hiked. But in th. t qsoi and i 990s there were far feu,er people headed arvay from the lift lin., irrto th. mounrains, Courtemanch said. As backcounrry gear has become lighrer and easier to use, more skiers starred venturing away from resorrs. "Every vear people are skiing more and using more extreme routes,', Courtemanch said. "Skier numbers are increasing and people are skiing into more places theyve n.r,.,,kiejb.fo.e.,, In 1999, Jackson Hole Mountain Resort opened its gates to the back_ counrry, allowing people eas1. access ro out-of-bounds skiing, r.r,hich u.as also bighorn winrer range, on rhe Bridg_ er-teton National Foresr. Courtemancht study had many parrners including rhe Universiry of \Wyoming, Grand Teton Nationai park, Bridger-Gton and Caribou-Thrghee national forests and the department. Funding came from many sources, toor including Grand Teton National park, \Tyoming \fildlife Sheep Foundation and the \fyoming Governort Big Game License Coalition. The Ta&sol, Hole Mounrain Resorr p,.ouided Free Iilr access for r.esearchers and helped issue GPS units to skiers headed out of bounds through the seven backcountry gates at the resort. With Courtemanch's study finished, the agencies need to decide what ro do to prorec the Gton bighorn sheep. Vyoming \fildlife I 41

5 That involves bringing together the aforementioned partners as well as other stakeholders. "Everything is on the table," she said. Given the magnitude of disturbance sheep experience when they encounter backcountry users, land managers will likely consider winter closures, said Dale Deiter, district ranger for the Bridger-Teton National Forest. "Just being a small and isolated population, no matter what we do, that population is probably going to always be at risk," Deiter said. "If there are things managers can do to take a little pressure offthe animals, it is worth it." "Any management changes will be science-based and in the best interest of the sheep," Courtemanch said. "Some of the area's most popular backcountry ski areas are not at risk for any sort of new regulations fo protect sheep. Teton Pass on the national forest and25 Short in Grand Teton National Park are places where there isnt sheep and human overlap. "There are so many areas to recreate around Jackson Hole. I think that most people would consider going to areas where maybe there is less impact on wildlife." It will come down to an equation those living in Jackson Hole are already familiar with: Finding a balance in all the reasons people are passionate about the area the wide open spaces, wildlife and outdoor recreation. - "And bighorn sheep, in many ways, represent all those things," Kilpatrick said. "Bighorn sheep are iconic. They are symbolic of what we love about wildness and backcountry." Dayton is the editor of Oufdoors -Kelsey Unlimited,the magazine of the OutdoorWriters Association of America. 4 td T H Due to its low population, the bighorn sheep herd near some newly popular back-country ski areas will always be at risk of declining. Photo bytim Doolin 42 January2016