When voters passed Proposition 114 to require Colorado Parks and Wildlife to return gray wolves to the state, the ballot initiative specified when and where wolves would arrive. But it doesn’t say which kind of wolves to bring back.
This story first appeared in The Outsider, the premium outdoor newsletter by Jason Blevins.
In it, he covers the industry from the inside out, plus the fun side of being outdoors in our beautiful state.
Conservation groups and at least one state wildlife commissioner are reiterating that wolf reintroduction is an opportunity not just to return a keystone species to ecosystems in the state, but to aid an endangered animal in dire need: the Mexican gray wolf.
“The Mexican wolf is much more imperiled, so doing a project to reintroduce wolves would benefit the Mexican wolf to a great extent — possibly even save it from extinction,” said James Jay Tutchton, who serves on the Colorado Parks and Wildlife Commission and worked on wildlife cases as a lawyer for WildEarth Guardians, the Center for Biological Diversity, and Defenders of Wildlife for 27 years. He said he has made this point at several commission meetings and with Colorado Parks and Wildlife biologists.
The state agency’s first draft of the plan for reintroducing wolves to Colorado will debut Friday at the commission meeting. The plan will not include Mexican gray wolves, and there are a lot of “biological and political and legal” reasons for that, said Eric Odell, the state agency’s biological lead for wolf reintroduction. But wolves released by the December 2023 deadline will be just the first in a multi-year effort, Tutchton points out, and he contends there’s still time to change that approach.
Mexican gray wolf is half the size of a gray wolf
Mexican gray wolves are a distinct subspecies of wolf, Canis lupus baileyi to the gray wolf’s Canis lupus. They weigh 50 to 80 pounds, significantly less than gray wolves, which can weigh up to 175 pounds. Their pelts are generally golden and gray. Both wolf species were deliberately exterminated from much of the lower 48 by the mid-1900s, then restored through U.S. Fish and Wildlife Service programs launched in the 1990s.
Mexican gray wolves are now found in southern Arizona and New Mexico’s mountains, often at high enough elevations they live amid pine forests, snowmelt-fed rivers and elk herds.
Gray wolf numbers have climbed to an estimated 6,000 and spread from reintroduction sites in Yellowstone National Park and Idaho to other Western states, considered a remarkable conservation success story that has led wildlife managers to ease wolf protections in several of those states. In the same time frame, Mexican gray wolves reached just 196 at their last official count. They rank among North America’s rarest mammals, so infrequently spotted that a Fish and Wildlife Service intern can spend an entire summer in their range without seeing one that isn’t tranquilized or trapped.
“If you’re going to do a project like reintroduce wolves to Colorado, you might be doing a service to conservation if you introduce the rarer of the species,” Tutchton said.
“Mexican wolves need Colorado, or at least the southern Rockies, in some regard,” said Chris Smith, Southwest wildlife advocate for WildEarth Guardians.
But Odell points out that Mexican wolf numbers have continued to climb, if gradually, and there aren’t major signs the program to restore them in their historic range is failing.
“That population has demonstrated slow but good success,” Odell said. “Every year, there’s more wolves than there were the year before, for the most part. So, it’s growing, but it’s growing slowly, as small populations sometimes do.”
The technical working group of scientists and staff from other wolf reintroduction or management efforts Colorado Parks and Wildlife convened reviewed potential sources for wolves. They considered Mexican gray wolves and in a November 2021 report labeled them the least desirable choice. That was in part, the report states, because Colorado is not the historic habitat for Mexican gray wolves, which generally lived farther south.
At the time, bringing Mexican gray wolves to the state would also have meant importing an endangered species — and all the associated headaches. Far better, the report said, to go to northern Rocky Mountain or Pacific Northwest states for gray wolves.
The Trump administration removed gray wolves from the endangered species list in 2020, which granted state wildlife departments control over them throughout the country. (They remain off the list and subject to hunting in Idaho, Montana and Wyoming.) The U.S. Fish and Wildlife Service separated Mexican gray wolves as a distinct and uniquely threatened subspecies in 2015, so it retained endangered status and federal management.
But then, in the ongoing whiplash around gray wolf protections, a court vacated the Trump-era rule on gray wolves in February 2022. Gray wolves were once again considered endangered outside of a set list of states, and the Fish and Wildlife Service would again have to handle the paperwork for moving wolves to Colorado.
“Gray wolves had a sort of procedural advantage at the time that we began the process, but that procedural advantage is gone,” Tutchton said. “Now, both the gray wolf and Mexican gray wolf are protected by the federal government, and the hoops you’d have to jump through are the same.”
Those hoops include a 10(j) rulemaking, the tediously named process for establishing “experimental populations” to recover a species and applying more flexible rules to its management, like permitting the removal, even lethally, of predators that attack livestock. Now that gray wolves are considered endangered, the Fish and Wildlife Service is drafting a 10(j) rule to release them in Colorado.
A 10(j) rule also guides Mexican gray wolf management. That rule was just revised, after a judge ordered the Fish and Wildlife Service to revisit an approach conservation groups’ attorneys successfully argued amounted to slow-walking the species toward extinction.
Had that revision added a recovery area in Colorado, it would have saved the Fish and Wildlife Service time and taxpayer money, argues Greta Anderson, deputy director of the Western Watersheds Project, which advocates for wolves as a component of healthy ecosystems.
“They’d be home free right now — they could be putting wolves on the ground,” she said.
But Odell sees it differently: “If we were to use Mexican wolves for a source population, it would require a revision of all of that work, which took years and years.”
Politics, not biology, slammed the door before
It’s not the first time Mexican gray wolves have missed a possible entry into Colorado. A 10(j) rule pairs with a recovery plan for the species. That plan maps not just how things are handled today, but long-term goals for what a self-sustaining population of those animals might look like. When the Fish and Wildlife Service convened a group to work on a draft of that plan for Mexican gray wolves, an early iteration suggested three groups spread over Arizona, Colorado, New Mexico, and southern Utah, near Grand Canyon National Park, just close enough for individuals to disperse among the groups and interbreed, and a total of 750 wolves. But the states weren’t having it.
Governors of the Four Corners states responded by demanding a “Mexico-centric” approach instead. Colorado’s contributions included a 1982 Colorado Wildlife Commission resolution opposing free-roaming populations of gray wolves or grizzly bears in the state, a stance the commission reiterated with specific opposition to Mexican gray wolves in 2016.
“There was no reason to discriminate against Mexican wolves, other than they were cowardly,” Tutchton said. “It was political, not science, and I think it just showed cowardice or animosity toward the recovery of endangered species, particularly wolves.”
But that’s still the line. Research has volleyed back and forth — at times in the opinion section of scientific journals and co-authored by employees of state wildlife departments — that argues against using, for example, genetic markers of Mexican gray wolves found in specimens collected in the Colorado San Luis Valley or even Nebraska as evidence those wolves lived here. Some also point to denning locations this spring that edged farther north in New Mexico than seen in the nearly 25 years of recovery work as signs the species is eager to shift into cooler climates. But Odell calls wolves “generalists,” flexible enough to live from the Arctic to the Sonoran Desert, so unlikely to face major obstacles even in a hotter, drier Southwest. That also means there’s no reason to expect Mexican gray wolves wouldn’t do “OK” in southern Colorado, Odell said, but they have plenty of viable habitat left for them in New Mexico, Arizona and Mexico.
For now, Mexican gray wolves live with a hard line drawn on where they can move. If one wanders north of Interstate 40, which bisects Arizona and New Mexico, it is trapped and brought back to the southern halves of those states. This is a move some researchers have argued compromises the best science for ensuring this species survives with social tolerance for its presence among ranchers and hunters.
“I suspect the Fish and Wildlife Service would happily let wolves roam north, rather than spending taxpayer money to go capture them,” Smith said. “They won’t publicly say this — they can’t publicly say this — but the Fish and Wildlife Service wants states to give them the room to allow Mexican wolves to go further north, whether that would be active reintroductions or just letting them roam.”
The Fish and Wildlife Service’s Mexican wolf program staff did not respond to an interview request for this story.
“Wolves want to move, especially dispersing young males trying to set out new territories, and to sort of keep them within this really small, defined geography has been really an unfortunate political decision,” Anderson said. “I think that Colorado missed an opportunity to reintroduce Mexican wolves for their own sake, because it’s a really cool species. They also missed it from the perspective that they could be helping this species recover in a big way, and the reasons that they missed it are not very clear.”
She’s been making the case to wildlife managers in Colorado to see it differently.
“The conflict over wolves is really a conflict over land use and whether we want wild things and wild places, or whether we want the landscape sanitized for extractive uses,” Anderson said. That affects not just aesthetics, but the ability of those landscapes to combat climate change, she added, and “the more we can work to restore holistic ecological function in our wild places, the better that will serve us as humans.”
For now, at least, Colorado Parks and Wildlife will try to recruit wolves from similar ecosystems with similar prey bases, Odell said. Idaho, Montana and Wyoming top the list. Eastern Oregon and Washington might be close enough. None of those arrangements are finalized, Odell said, but they will be soon. Either region would provide the same wolf species already spotted in northern Colorado.
But Colorado probably wasn’t their home range either. It was ground for a different subspecies of wolf.
Because trappers arrived in the American West well before ecologists, much of what we know about which wolves lived where is based on details about where wolf pelts were collected. As a senior biologist with the Fish and Wildlife Service, Edward A. Goldman had examined hundreds of pelts and skulls by “The Wolves of North America” was published in 1944. In it, he described a subspecies living in Colorado as Canis lupus youngi, the southern Rocky Mountain wolf. He estimated it was mid-sized based on its pelts, which were buff. One found near Fruita was “buffy white,” with a thin line of black-tipped hairs along its back, and black tufts at its tail.
The last southern Rocky Mountain wolf was likely the one Fish and Wildlife Service trapped and killed in the southeastern San Juan mountains in Conejos County in 1945, said Michael Robinson, senior conservation advocate with the Center for Biological Diversity. His book, “Predatory Bureaucracy: The Extermination of Wolves and the Transformation of the West,” opens with that scene.
Planning for lost genetic diversity
Southern Rocky Mountain wolves were one of 23 subspecies Goldman identified, most of which are now extinct. The current number of wolf subspecies is five, or seven — debate is ongoing. Some science suggests a gradient of wolves once covered the continent with regional variations in size and color and almost certainly overlap and interbreeding among them. Goldman’s assessment of Mexican gray wolf habitat showed it largely in Mexico, but as with taxonomy, there’s been debate and tinkering with where and how those lines are drawn.
“At a certain point, it’s largely irrelevant where the original range was, because the subspecies that were — (like) the Mogollon mountain wolf — are gone,” Robinson said.
Since there’s no opportunity to return the original, he contends, why not consider Mexican gray wolves? They might even more closely resemble southern Rocky Mountain wolves. And there could be practical benefits to that, Tutchton adds, as a smaller wolf would eat less and might be less successful taking down cattle, though ranchers in New Mexico and Arizona would undoubtedly contest the latter point.
But if Mexican gray wolves did live in southwestern Colorado, and gray wolves were in northern Colorado, they might be close enough to mix. That could recreate that theorized historic gradient. But it could also compromise, or at least confuse, the decades of work toward preserving Mexican gray wolves as a distinct subspecies, Odell said. Gray wolves are bigger and form larger packs, he added, so might outcompete Mexican gray wolves, swamping that population.
“Then what the Fish and Wildlife Service is aiming to recover no longer exists because it’s been infiltrated with the genetics of the northern wolves,” he said.
Wolf advocates argue that at some point, there will have to be an influx of outside genes. Mexican gray wolves had been knocked back to just seven survivors when efforts to avoid its extinction began. Over the decades, more than half of even that limited genetic diversity has been lost. Genetic diversity in the captive population of about 300 wolves in nearly 50 facilities around the country has fared just slightly better. When the U.S. Fish and Wildlife Service made the case for the subspecies’ endangered status in 2015, threats listed included inbreeding and loss of genetic variation and adaptive potential.
Wolves in the wild now are as closely related as siblings. That is a dangerously high level of genetic similarity that’s likely to lead to smaller litters and fewer pups surviving, among other problems. If those signs are showing up now, Anderson said, they may be camouflaged by the fact that the Mexican gray wolf program managers leave supplemental food for packs with young. And even with that, Robinson pointed out, computer models projecting population trends into the future show that several decades from now, the numbers tank.
“Just having more places to put wolves from the captive population would help create new pockets, new potential for outbreeding from the Arizona and New Mexico population,” Anderson said.
If Mexican gray wolves lived in southwestern Colorado, Robinson said, the state could become a “blending zone” where a few northern wolves breed with Mexican gray wolves, mixing in some new genetics at a distance from core Mexican gray wolf habitat. The hybrid might even be the nearest we could come to recreating the southern Rocky Mountain wolf — “not as good as the original,” Robinson said, “but something close.”
“The biggest danger of all is for there to be zero connectivity,” he said.
Mexican gray wolves are “not quite at that point yet” of needing outside genetics, Odell said, but “in time, that may be more important.”
For now, the U.S. Fish and Wildlife Service’s approach to head off the genetic crisis for Mexican gray wolves sees careful matching in captive breeding programs, the pups from which are then moved into wild dens. The hope is that they will survive, find a mate, and have pups of their own, adding their genetics to the wild. Of 83 pups “cross-fostered” since 2016, just 13 have been documented surviving to breeding age. They face a number of obstacles: One such cross-fostered wolf was recently found dead in New Mexico. Its cause of death has not been released, but illegal shooting has riddled that population for decades.
For wolves in the Southwest to mix with wolves in Mexico likely requires trucking the animals across the border. That’s not the point, Tutchton said, of what the Endangered Species Act mandates for wildlife’s recovery and shouldn’t be the ideal ending for reintroduction efforts.
“That kind of constant intervention and hovering of humanity over the species is not success,” Tutchton said. “Success is when the species is functioning as it did for thousands of years before we screwed things up.”