A sub-adult male grizzly bear euthanized Monday south of Ten Sleep is yet more evidence the species is spreading well beyond the boundaries of what is considered suitable habitat for the area’s apex predator. Wyoming’s top large carnivore expert said it’s clear the species is fully recovered and looking for more room outside a crowded Demographic Monitoring Area in the Greater Yellowstone Ecosystem.

Grizzly bears have not been documented in the area south of the Bighorn Mountains since long before the species was listed under the Endangered Species Act in the 1970s, according to the Wyoming Game and Fish Department. But recently they’ve been close.

Last July a grizzly bear was documented on video near Lysite and in May grizzly tracks were documented west of Kirby in the tiny town of Gebo. The sub-adult bear found eating calves near Ten Sleep earlier this week was unknown to the department before its capture and it’s impossible to know how he traveled to Washakie County.

The capture occurred on private land on the edge of the Bighorn Mountains. Yet, some people are jumping to the conclusion the traveler had made it to the Bighorn National Forest. There still hasn’t been a confirmed grizzly in the forest, yet.

Last year a grizzly bear was also discovered in the Pryor Mountains in July — not far from the Bighorns. It prompted officials to warn visitors to avoid traveling at dawn, dusk or night (when bears are typically most active) and to carry bear spray and “know how to use it.”

In Ten Sleep, officials first investigated reports of an injured cow with wounds consistent with a grizzly bear attack. Wildlife managers verified nearby tracks and signs of blood that suggested the bear frequented the ranch for about a week. Two calves were also missing.

The bear was euthanized by Wyoming officials after consultation with the U.S. Fish and Wildlife Service due to its involvement in depredation and its behavior frequenting the ranch. The Service makes the final call on the fate of all captured grizzly bears due to protections extended to the threatened species by the Endangered Species Act.

Management authority for grizzly bears rests with the Service, but Game and Fish officials handle nearly all grizzly bear conflicts and conduct significant levels of monitoring, research and public education in accordance with the department’s Grizzly Bear Management Plan.

“Wyoming’s grizzly bear population is managed and monitored where suitable habitat exists as designated by the USFWS and informed by the Interagency Grizzly Bear Study Team,” said Game and Fish Director Brian Nesvik. “The Bighorn Mountain Range is not suitable habitat and the department is not interested in allowing grizzly bears to occupy this area. Their expansion into unsuitable habitat leads to increased conflict potential between bears and humans, which impedes the success of grizzly bear conservation.” 

Ironically, the department is often accused of intentionally moving grizzly bears to the Bighorns, said Dan Thompson, large carnivore program supervisor.

“We’ve been accused of moving bears there, which is absolutely false. And we've been accused of hiding information, which is also absolutely false,” Thompson said. “Promoting bears in historic but now inhospitable habitats isn't beneficial to grizzly bears.”

Even if a grizzly bear was discovered that had not been feeding on livestock or involved in a conflict, the bear would be removed from the area because the Bighorns are not suitable habitat due to the potential for conflicts, Thompson said.

“Talking about [grizzly] bears in the Bighorns 20 years ago was like science fiction,” he said Tuesday in an interview with the Tribune while taking a break from the commission meeting in Riverton. “But it's not like we weren't prepared for this. This is something we've talked about since bears started expanding within the Absaroka front.”

Thompson remembers talking with his bosses while doing some black bear work in the northern Bighorns. He asked his bosses what would happen if he caught a grizzly bear instead of their smaller cousins. That began a long conversation that continues today.

“We already have contingency plans if we do have a grizzly bear in the Bighorn Mountains that, if we have the ability to capture it, we would move it back into the suitable habitat unless it was involved in a conflict. And that's a different situation,” he said, meaning the bear would likely be euthanized.

The location of the conflict was more than 80 miles from the eastern edge of the DMA — the area considered biologically and socially suitable for grizzly bears in Idaho, Montana and Wyoming. Grizzly bears have been increasingly documented heading east in recent years, including a sow and two cubs that made it to Byron, passing through the Powell area before being captured and lethally removed.

For many, the expansion of grizzly bears is troubling. And conflict resolution is a big part of the job for the state’s large carnivore biologists. Not only does the department deal directly with every bear in conflict, the department also pays for damage claims. The preliminary 2025 budget is now asking for more than $2 million to pay landowners and ranchers making damage claims — more than four times the amount requested just six years ago.

Current population estimates show there could be as many as 1,100 grizzly bears inside the borders of suitable habitat, but with more grizzlies moving outside the DMA in search of their own piece of ground every year, their expansion often means they end up in harm’s way.

Scientists can’t count every bear in an ecosystem encompassing nearly 20,000 square miles in the three-state area bordering Yellowstone, said Frank van Manen, Interagency Grizzly Bear Study Team (IGBST) leader. And that doesn’t count the more than 6,500 square miles that the species occupies outside the DMA. Those bears are not included in the official estimates.

“Without someone throwing millions of dollars extra at [monitoring efforts], I don’t see a way of being able to monitor [outside the DMA] into the future,” van Manen said.

More than 50 grizzly bear mortalities were reported to the U.S. Geological Survey in 2023, with 28 of those deaths happening in Wyoming and 15 of those happening outside the DMA. Nearly half of all mortalities in the DMA last year were euthanized in management decisions, with 18 of 25 euthanizations happening in Wyoming.

The Yellowstone Ecosystem Subcommittee of the Interagency Grizzly Bear Committee is holding its Spring 2024 meeting April 24-25 at the Courtyard by Marriott in Bozeman, Montana.