Upper Shoshone mule deer at a crossroads as Cody-area development shrinks winter range
BRETT FRENCH | bfrench@billingsgazette.com
In a cave high atop a mountain, in a remote region near Yellowstone National Park, a mule deer doe gave birth to a fawn this spring.
To get to the birthplace above Bear Creek she had hiked 28 miles while gaining 22,765 feet and losing 20,229 feet on an average slope of 21%.
Tony Mong, a Wyoming Game and Fish Department wildlife biologist, learned about the birth because the doe was wearing a collar that captured video every two hours. The shots from under the female deer’s chin shows the steep 9,100-foot high mountainside on which she stood leading down to a lush landscape along the North Fork Shoshone River thousands of feet below.
“I guarantee that 95% of us could not get there, and she has found this cave,” Mong told an audience during a Dec. 5 talk at the Draper Natural History Museum in Cody, Wyoming.
Another clip shows the mother deer holding the fawn down with both front legs as she licked it clean of afterbirth.
“When most people in Wyoming see mule deer from the Shoshone herd on their lands, they don’t realize how long and difficult of a journey they’ve been on,” said Sara Domek, Migration Program manager for The Nature Conservancy in Wyoming, which provided funding for the video collars. “Using these video collars is an easy and interesting way to show people how important this land is and how we can better keep mule deer habitat intact for these iconic animals.”
Tough terrain
The doe was one of 25 deer wintering near Cody that was trapped and fitted with a video collar. Another 210 were tracked using GPS collars that provide data on how far the animals move, when they travel and the elevation they gain and lose. Along their travel routes, trail cameras have been set up to help the scientists understand the weather conditions during migrations, other animals occupying the area and to sometimes identify individual animals.
The data points have produced more astounding information on migratory wildlife in a state that has become iconic for studies of mountain-traveling pronghorns (Path of the Pronghorn), elk and mule deer, including one doe that made an eye-popping 480-mile roundtrip.
Camera traps along the routes have captured stunning photos and video of the challenges they face during their treacherous hikes, such as high-water stream crossings, as well as identified how they follow the “green wave” of vegetation into the mountains while sometimes struggling through deep snow.
To understand the challenges facing the state’s dwindling mule deer population — which has plummeted from around 400,000 in 2005 to about 200,000 today — Wyoming Game and Fish staff are conducting intensive monitoring of five herds, including the Upper Shoshone herd.
Cody deer
“The mule deer of the North and South Fork of the Shoshone are so easily accessible, easily seen and in many cases, easily taken for granted,” Mong said.
Their population numbers between 6,500 to 8,000, 93% of which are migratory. The average distance they travel into the backcountry surrounding and in Yellowstone National Park is 75 miles one way. Their typical elevation gain and loss is around 22,000 feet. The twice a year trek can take from 10 to 20 days, depending on the weather and other factors.
“Just by removing or modifying one fence, we can make their trip a little bit easier and make sure they are able to move across the landscape just as they always have,” said Domek, of The Nature Conservancy.
A study published in 2020 showed one of the collared deer traveling 133 miles one way, starting at the mouth of the South Fork Shoshone River near Buffalo Bill Reservoir and ending at Jenny Lake in Grand Teton National Park. This year, one trekked all the way into the neighboring state of Idaho.
“Mule deer typically start their migrations around mid-May to try to get to summer range by the time that they drop their fawn, so usually by mid-June,” Mong explained.
That means does are making these hikes up and over 8,000-foot passes, sometimes in deep snow, when they are just a month away from giving birth. If snow blocks their route, the doe will stop to give birth, and then the newborn fawn has to continue the hike to summer range.
Mong compared the experience to the travails of the fictional character Frodo Baggins in the book and movie “Lord of the Rings.”
Return trip
By September or maybe as late as October, the deer begin leaving the Greater Yellowstone Ecosystem’s backcountry. Snowfall is the cue to depart.
“If we have a big snow event in early September, they’re probably not going to move,” Mong said. “But if we even have a little snow event in October, they’re going to get out of there.”
Newly born fawns are traveling from a wildlife paradise — a place with few roads, no fences or livestock and hardly any people or automobiles — to return to the increasingly more populated upper Shoshone river drainages.
“The difference between what they experienced during the first part of their lives and their second is a direct affront to their senses,” Mong said.
“These animals traverse the rugged Absaroka Range and cross the Yellowstone River all to end up in someone’s backyard for the winter,” said Domek, of The Nature Conservancy.
Now instead of 3,000 square miles of wild country to roam, they are concentrated on about 1,000 square miles of terrain. Of this, about half is public ground with the rest privately owned. About one-third of the private land is less than 120 acres in size, so the deer are concentrated on small patches of open ground.
“So we have this collision,” Mong said, of deer traveling from the least-populated area in the Lower 48 states, to a landscape crisscrossed by roads and fences and increasingly being subdivided for homes.
“They are being packed into these areas,” Mong said. “More people, which means more traffic, more fences, more dogs.”
Such confinement and the buzz of human activity increases stress on the animals, requiring them to burn more energy at a time of year when their fat reserves are naturally dwindling.
“The Nature Conservancy is dedicated to helping reduce fragmentation of ungulate migration habitat, including that of mule deer like those in the Shoshone herd,” Domek said. “Through the deployment of these video collars, we improve the science and knowledge of these migration routes, bearing witness to the specific challenges these deer face during these migrations.
“With this knowledge, we will continue to work with our partners to improve the habitat through conservation projects such as wildlife-friendly fence modifications and removal of unnecessary fencing in targeted areas,” she added.
Concentrating the animals also leads to a greater chance for spread of chronic wasting disease, an always fatal infection of the brain. In less than five years, prevalence of the disease has gone from 3% to 25% in the Upper Shoshone herd.
“A lot of that has to do with the way we are developing and the way these animals are getting pushed into smaller and smaller areas,” Mong said.
Crossroads
During his work with the Upper Shoshone mule deer herd, Mong developed a close kinship with the animals. Now he’s become an ambassador for them, urging those listening to his talk to do their part to help the native wildlife that have occupied the rugged region of northwestern Wyoming for the past 10,000 years.
“If you live in this county, you are part of the story of these mule deer,” he said. “I know at times it seems hopeless. Disease, different weather patterns, balancing growth, bad winters — you name it — it seems to be happening, and it can make us feel hopeless.
“I do believe we’re at a crossroads,” he continued.
It’s time to “use the data, the knowledge and the resources we’re afforded to do things differently,” Mong said, urging people who care about mule deer and other wildlife to advocate for their protection at the local and county levels by backing investment in conservation easements and promoting zoning.
“I really think that these mule deer represent a connection to a wild place, a connection that for most people, regardless of where you’re brought up … there is some primal drive to be connected to wild places,” Mong said.
“And mule deer, for us especially, are a tangible, accessible way to be a part of the mystery and the wild spirit of our western landscapes.”
Original Source: Billings Gazette
