One of Wyoming’s flagship mule deer herds has lost more than half of its animals to an unusual inverted snowpack that’s still killing scores of animals well into April.

The dire situation has some hunters calling on the Wyoming Game and Fish Department to temporarily suspend hunting in some areas.  

About 30% of the does in the Wyoming Range Mule Deer Herd had died by late March, when Gov. Mark Gordon convened a town hall-style meeting in Pinedale about winter’s dire effects on ungulate populations in portions of Wyoming. At the time, biologists explained that survival rates could continue to plummet — and their warnings proved prescient. 

In the two weeks that followed, another 20% of the adult female deer in the Wyoming Range succumbed to starvation and other winter stressors, a state biologist told WyoFile on Friday. 

“As of yesterday (April 13), doe survival in the Wyoming Range was around 47%,” said Embere Hall, the Wyoming Game and Fish Department’s science, research and analytical support unit supervisor.

Bucks in the herd, last assessed at roughly 28,000 animals, were about equally depleted, with just 49% surviving. Fawns are all but gone. Just two of the 100 collared yearling deer from the Wyoming Range Herd were still alive when Hall spoke to WyoFile. 

“In the Wyoming Range, it won’t surprise me that we will lose all of the marked juveniles that we have before the winter is over,” she said. “In fact, that’s likely.”

The mortality data is not comprehensive. It’s not like every fawn in the entire herd will die, Hall said.  

But the survival rates Hall cited come from a significant sample size of the herd acquired via Wyoming’s Mule Deer Monitoring Project. That multimillion-dollar surveillance effort, launched in 2022, is generating data about the state’s 37 mule deer herds, which have a combined population of roughly 300,000 animals. 

The project affixed 330 GPS collars onto 200 does, 100 fawns and 30 bucks from five focal mule deer herds: the Wyoming Range, North Bighorn, Upper Shoshone, Sweetwater and Laramie Mountains herds. More focal herds will be identified in future years. 

Based on this dataset, winter mule deer mortality rates are much less dire statewide. 

“Winter doesn’t affect mule deer the same across the state,” Hall said. “We have pretty concerning survival numbers from the western part of the state — particularly the Wyoming Range — but we see notably different trends in areas that have experienced a different version of the winter.”

Combining numbers from the five focal herds, statewide survival rates on April 13 registered at 75% for does, 78% among bucks and 61% for fawns. 

Pockets of death

Northern Wyoming herds — North Bighorn and Upper Shoshone mule deer — have fared the best, with more than 90% survival of does, the reproductive engine of herds that are most important to populations. In the Sweetwater Herd, which dwells in central Wyoming’s Granite and Green mountains, doe survival was 86%. In the Laramie Mountains, some 81% of marked does remained alive. 

“I feel really grateful that we have these kinds of data to lean on,” Hall said, “because we can see the landscape through the deer’s experience and begin to understand winter isn’t created equal for everyone.”

Where it’s at its worst in the Wyoming Range, 2022-’23 will go down as easily the deadliest winter in the modern era for a mule deer herd that’s been closely studied for more than a dozen years. The two most recent severe winters for the herd, in 2016-’17 and 2018-’19, killed only 30% of does, whereas winter 2022-’23 already exceeds 50% mortality. 

Once 50,000-plus-deer strong, the Wyoming Range Mule Deer Herd is among the largest mule deer herds in the United States. It’s renowned for producing big-antlered bucks that attract trophy deer hunters from around the state and country. 

The Wyoming Game and Fish Department updated its fall 2023 hunting season proposals for Wyoming Range deer in winter’s wake. In the Wyoming and Salt River ranges and beyond in western Wyoming, mule deer rifle hunters will have a one-week shorter season. State officials are also planning to implement a new antler point restriction, requiring that any mule deer harvested have three points or more on either antler. Last, youth hunts have been altered to exclude does and fawns.

Game and Fish biologist Gary Fralick, who’s in his third decade of working with Wyoming Range mule deer, described these adjustments as “substantial changes.” 

But some hunters and outfitters want to see the state go even farther to protect the health of the herd. 

“What’s it going to hurt, if you shut some areas down for a year or two?” said Rock Springs resident Joey Flaigl, a co-founder of the Muley Fanatic Foundation whose deer hunting grounds are in the eastern Green River basin. “That way you’re totally avoiding someone harvesting any deer whatsoever. Give it a try.” 

Suspend the hunt

Faigl recalled totally suspended hunting seasons in the 1980s in response to severe winters. The tactic worked, he said, and populations surged as seasons were eased back open. 

Pinedale resident Paul Ulrich, who hunts Wyoming Range deer in the La Barge Creek area, said he and his family would be willing to give up hunting the area while the herd is on the mend. 

“We love to hunt — it’s what we do all fall — and for Wyoming’s wildlife population, if it means us taking a year or two off, it’s the right thing to do,” Ulrich said during the Pinedale town hall meeting. 

Total suspensions of the hunting seasons were not on the table during Game and Fish’s deliberations this winter, Fralick said. Doing so, he said, wouldn’t have many benefits. 

“Hunting bucks won’t have any negative influence on the population’s ability to increase,” he said. 

Faced with a half-sized herd, other mule deer hunters want to see the state take other steps to reduce hunting pressure in the Wyoming Range.

“This year is going to make 2017 look like a cakewalk,” said Freedom outfitter Ted Jenkins, who guides hunters on both sides of the Greys River.

In Jenkins’ view, now is the time to phase out “general” license deer hunting in the region. Those licenses can be bought over the counter by Wyoming residents, the effect being that there’s no real cap on hunter numbers. 

“I’ve guided up there since 1995, and I’ve increasingly seen — year after year — the hunting pressure get worse and worse and worse,” Jenkins said. “Where’s our line in the sand? When do [numbers] get low enough, to the point where they agree that it’s time to make the change?”

Jenkins did not favor suspending the hunting season. He’s aiming to take out two to four guided mule deer hunters this fall, down from the six to 10 he guides in a typical season. 

“I think I’m going to be pushing it to do that,” Jenkins said. “I think all of us have lost prospective clients for this year and in the next few years, obviously. And I don’t anticipate myself hunting for many mule deer or antelope for the next five to seven years.” 

New hunt proposals

The Wyoming Game and Fish Commission considered the department’s amended hunting season proposals during an all-day meeting on April 17-18.

Because of deep snow on winter ranges and dying deer, the commissioners are also weighing whether to delay the May 1 shed antler hunting season. Chief Game Warden Rick King told commissioners Monday that his recommendation would be to postpone the popular antler gathering season on public land.

“Big game animals are still on their winter ranges — they’re not moving and not showing any indications they’re going to move,” King said. “The conditions on the ground are such that it doesn’t look like things are going to change much in the next week or two.” 

Commissioners did not vote on the recommendation, however, and will instead consider whether to delay the shed hunting season at a special meeting next week.