A third gray wolf reintroduced into Colorado last December has died, CPW confirms

DENVER — A gray wolf in Grand County has died, Colorado Parks and Wildlife (CPW) said on Thursday, just days after the announcement that a sickly male wolf had died shortly after a six-member wolf pack in the county was captured for relocation.

The cause of death remains under investigation.

In a brief press release on Thursday, CPW said the agency learned that a male wolf that had been reintroduced in December 2023 had died.

CPW Director Jeff Davis said staff received a mortality signal from the wolf's GPS collar on Sept. 9 and confirmed it had died on Sept. 10.

"While this is sad news, these types of restoration efforts consider anticipated mortalities in our planning and a degree of wolf mortality, just like for any wildlife, is expected both during restoration efforts and on an ongoing basis," Davis said.

Because gray wolves are a federally listed species under the Endangered Species Act, CPW is in direct consultation with the U.S. Fish and Wildlife Service about the next steps, CPW said.

"Wolf survival is highly variable between regions, but three of the 12 wolves in Colorado (10 translocated wolves and two that remained in Colorado) dying in nine months is not cause for alarm and is in line with typical wolf survival," said Travis Duncan, public information officer with CPW.

This marks the third time a wolf that was reintroduced in Colorado has died since 10 of them were first put back on the landscape in December, as voters mandated in 2020:

1. The first was found deceased in April after a likely mountain lion attack.
2. The second, an adult male wolf, was found with several injuries to his right hind leg that were unrelated to the capture of the Copper Creek Pack, which had been identified in connection with multiple livestock depredations. The animal's injuries appeared to be from an attack by another carnivore, and he had a low body weight, CPW said. He died in early September.
3. The third was found deceased on Sept. 10, as detailed above.

Environment

Colorado wolf pack captured for relocation; 1 found in poor condition dies

Stephanie Butzer

Per the Colorado Wolf Restoration and Management Plan, CPW listed the primary causes of wolf mortality as infectious disease, starvation and intraspecific strife, where the same species competes for limited resources and can attack each other.

The plan reads that any unexpected losses of wolves to preventable causes will prompt a review of "all associated factors, and, if possible, find ways to improve procedures."

"Unexplained losses or an unusually large number of losses during the first year of releases or following any modification to established protocols will prompt a full review of management procedures," it reads. "To assure high initial post-release survival, the project may be suspended at any time until likely cause(s) of problems are identified, and acceptable solutions can be implemented to resolve the problem."

The short-term success of the Colorado reintroduction has several benchmarks, which includes a high rate of survival in the first six months of the release — one wolf died within that timeline. A survival rate of less than 70% within six months would initiate a protocol review, which was not the case for Colorado wolves.

"The survival rate of the translocated wolves was 90% six months after release," Duncan said. "A survival rate of 90% is high for gray wolves, which only live to be an average of 3.5 to 4 years old in areas without human exploitation such as hunting and trapping."

Another marker of success is a low mortality rate over the initial two to three years after the release, according to the plan. A third benchmark is that the wolves form pairs and reproduce to establish packs, and that those pups grow up in Colorado and successfully reproduce within the state.

"Research suggests that annual mortality rates of 22 to >50 percent may suppress wolf population growth," the plan reads.

Read the full wolf restoration and management plan below or here.

The management plan examines the previous wolf reintroduction in the greater Yellowstone National Park and Idaho areas. The U.S. Fish and Wildlife Service created a recovery plan in 1987 for wolves in the Northern Rocky Mountains, which included reintroducing them in central Idaho in 1995 and 1996. The first wolves were reintroduced in Yellowstone in 1995.

"In Idaho, 30 of the 35 animals survived through the second year of reintroductions. In Yellowstone, 22 of the 31 animals survived through the second year of reintroductions," the plan reads. "Causes of mortality included interspecific conflict, illegally shot, wolf control action, struck by vehicle. Idaho had 85 percent survival and Yellowstone releases had 70 percent survival. It is anticipated that the survival rates will be within that range for the first years of reintroduction in Colorado."

As of now, with seven of the original 10 reintroduced wolves still alive in Colorado, the survival rate is 70%.

In addition to those animals, Colorado is home to two wolves that moved south into Jackson County from Wyoming, and four pups, which were born this year and are part of the Copper Creek Pack capture. CPW said they hope to release the pups together once they reach adult size, so they can hunt as a group.