The howl of the Mexican gray wolf (Canis lupus baileyi) is gradually returning to the backcountry soundscape of the U.S.-Mexican border region.

At last count, U.S. and Mexican experts involved in an over-four-decade binational reintroduction program estimate that at least 186 wild wolves currently inhabit Arizona and New Mexico, up from 163 two years ago and nearly double the number of five years ago. They reckon an additional 40 to 45 wolves—up from about 30 two years ago—roam the portion of the border region occupied by the northern mountains of Mexico’s Sierra Madre Occidental range.

After the Mexican gray wolf nearly disappeared due to government-supported eradication campaigns in Mexico and the United States, conservationists successfully lobbied for its listing in 1976 as an endangered subspecies of the gray wolf (Canis lupus). The next year, seven captured wolves became the base population of an ongoing, jointly managed, U.S.-Mexican species recovery program.

Actual reintroduction of the Mexican gray wolf, long advocated by conservationists, became a reality in 1998 when the United States Fish and Wildlife Service (USFWS) released 11 wolves in Arizona. Mexico followed suit in 2011, setting five wolves free in the northern border state of Sonora. Four of those wolves were illegally killed soon after.

To celebrate the 10th anniversary of the 2011 release, the Mexican Commission of Natural Protected Areas (Conanp) released four wolves on Oct. 12 in an area of the northern Sierra Madre Occidental range south of the international border in Chihuahua state.

Conanp says October’s release was the 16th to occur in Mexico in the past decade, in which a total of 63 individual wolves were returned to the wild. Moreover, at least 14 wolf litters have been born in the wild in Mexico in this period, the agency reports. The Mexican Secretariat of the Environment and Natural Resources (Semarnat) reported earlier this year that 45 pups were born in captivity in Mexico during the previous two years.

Releases have also continued north of the border. USFWS and other U.S. agencies spent $50,783,293 on wolf-recovery efforts from 1977 through the end of 2019, U.S. officials say.

Carlos López, a Mexican carnivore researcher who is active in various wildlife reintroduction efforts, says a positive development in Mexico was the recent inclusion of captured wild wolves within release groups. He notes that this works better than freeing groups solely comprising captive-bred animals, as had been the case in the past, because wolves are highly social animals, so those with wildland experience can transmit valuable knowledge to those that lack it. “They have proven very successful,” López, a professor at the Autonomous University of Querétaro, says of the mixed groups’ record of survival.

Today the reintroduction of the Mexican gray wolf in Arizona and New Mexico and northern Mexico is a notable example of international cooperation in the service of conservation. According to the USFWS, a 1996 memorandum of understanding expanded the groundwork for a collective approach by establishing a trilateral Mexican-U.S.-Canadian wildlife and conservation committee.

Today, over 50 Mexican and U.S. entities, including government agencies, zoos and other institutions, work cooperatively in the breeding, holding, transferring and preparing of wolves for release. The animals—often referred to on both sides of the border as lobos, the Spanish word for wolves—are typically fitted with radio collars to track their movements. Individual animals may be shipped back and forth across the border between facilities before their eventual release.

As of June 30, 2020, the USFWS estimated that 369 wolves were captive in Mexican and U.S. facilities. The captive program is overseen by the Maryland-based, nonprofit Association of Zoos and Aquariums (AZA) under the framework of the binational Mexican Gray Wolf Species Survival Plan. Mexican and U.S. wolf experts convene every year to discuss the nuts and bolts of wolf reintroduction, but the Covid-19 pandemic has necessitated virtual meetings for the past two years, organizers say.

Among the program’s participants has been New Mexico’s Albuquerque Biopark and Zoo, which has registered the birth of 78 wolf pups to date. The institution initially focused on breeding the animals, but has since concentrated on treating injured wild wolves. Located relatively close to wild packs, the zoo is a geographically choice spot for regional wolf rehabilitation, says Lynn Tupa, the zoo’s manager and a central player in the wider binational conservation network.

Early this year, nine wolves then housed in the Albuquerque Zoo—Kawi and her mate Ryder, both of them captive raised, and their seven offspring—were transferred to Mexico for possible release. Zoo staff, saddened to see the wolves leave yet hopeful the animals would make a successful transition to life in the wild, regarded the journey south as a homecoming of sorts for Kawi. She was born at the San Juan de Aragón Zoo in Mexico City in 2014, then was moved to Albuquerque in 2016.

Tupa says that to boost such wolves’ chances of survival in the wild, zookeepers must not allow the animals to become accustomed to them or to other humans. A zookeeper who has 20 years of experience with wolves, she says the animals still manage to surprise her. She cites the tunneling done by Kawi, “an amazing architect,” to construct a deep and complex den, and she points to the herding and tending of wolf pups performed by Archer, a juvenile male wolf. “They all learn from their parents,” Tupa says. “There are some natural instincts for hunting, but wolves need to learn. They truly are family-oriented. It’s all about the pack.”

Tupa says the Albuquerque Zoo is “thrilled” to be part of the binational conservation program to preserve the lobo, a native, apex predator and a New Mexico state icon. The University of New Mexico mascots are “Louie the Lobo” and “Lobo Lucy.” In November, the zoo was granted a five-year renewal of its accreditation by the AZA, a leading global player in the struggle to save endangered species. AZA President and CEO Dan Ashe says the Albuquerque Zoo and other zoos his organization accredits for species reintroduction work are meeting “ever-increasing standards to ensure that the animals’ best interests are always first and foremost.”

Despite the advances in Mexican gray wolf reintroduction, the predator’s status remains highly precarious on both sides of the border. Although Mexico and the United States are collaborating closely on a joint conservation goal, wolf-reintroduction conditions differ somewhat in the two countries. For instance, wolves in Mexico don’t have elk to feed on as in Arizona and New Mexico. There, they subsist instead on white-tailed deer, turkey and small mammals such as, perhaps surprisingly, skunks, López says. Unlike in the United States, where wolf reintroduction has occurred almost exclusively on federally owned land, “96%” of the Mexican land used for wolf recovery is privately owned, he says.

Although livestock-depredation insurance paid to ranchers in the wake of attacks by wolves and other predators is available in Mexico, there have been disagreements over the compensation formula, López adds.

“I think [insurance] has helped, and I think it has reduced mortalities,” López says. With the persistence of overblown fears about wolves, however, López contends wolf advocates must maintain a constant presence on the ground and be in frequent communication with ranchers. “We need to be there all the time,” he says.

The Mexican wolf expert voices cautious optimism about the lobo’s future, saying: “It seems like it’s going on the right track—maybe not as fast as people would like, but it’s getting there.”

In November 2019, the conservation gains made to that point prompted the Mexican government to change the Mexican gray wolf’s official status from “probably extinct” to endangered. Albeit incremental, the progress reflects diverse support. Wolf-reintroduction efforts in the country have received financial and in-kind backing from government agencies, universities and zoos. They also have attracted funding from the Global Environment Facility, World Wildlife Fund-Mexico and the eponymous foundation of Mexican entrepreneur Carlos Slim, described in the financial press as the richest person in Mexico.

The lobo received a high-profile media boost last year when Mexican soccer star Raúl Jiménez, known as the “El Lobo Mexicano,” publicly associated himself with a “Protect the Pack” wolf-conservation campaign.

Nonetheless, the trail to a restored wolf presence in the borderlands has been long and rocky. In the United States, wolf reintroduction has embroiled the USFWS as well as state game departments, environmentalists and ranchers in decades of political and legal battles.

The USFWS reports that since 1998, wolves in the U.S. accounted for 650 confirmed livestock kills and 3,350 estimated kills. Not surprisingly, opposition to all or parts of the wolf-reintroduction program comes chiefly from U.S. livestock producers and allied politicians.

As in Mexico, compensation in cases of livestock kills is available to producers in Arizona and New Mexico from private and public sources. But that hasn’t prevented the intentional, illegal killing of wolves by humans, which according to the USFWS constitutes “the largest source of documented wolf mortality” in Arizona and New Mexico.

Debate about wolf conservation has been rekindled in the United States as the USFWS accepts public comments for revised Mexican gray wolf management rules. Discussion of the rules, which have been released in draft form, has involved a variety of issues; but experts say the overarching question is whether wild wolves will be allowed to thrive, not merely survive.

The regulatory exercise stems from 2018 litigation in the U.S. District Court of Arizona in which the U.S.-based nonprofit Center for Biological Diversity (CBD) and allied conservation groups won a decision requiring the wolf-management rules overhaul.

Removal of U.S. cap
CBD staffer Michael Robinson says that as proposed, the federal rules would remove regulations limiting the U.S. population of Mexican gray wolves to no more than 325. They also would establish temporary restrictions on wolf killings currently allowed under certain special circumstances, he says.

“The most substantial victory for wolves is that the cap has been lifted,” says Robinson, who nevertheless criticizes the proposed rule for maintaining Interstate 40 as the northern geographic boundary of permissible Mexican gray wolf range in Arizona and New Mexico.

The USFWS designates an area between I-40 and the international border as the Mexican Wolf Experimental Population Area (MWEPA)—the U.S. portion of the border region that is earmarked for introduced Mexican Gray Wolf populations. For its part, Mexico has focused its wolf releases in the northern portion of the Sierra Madre Occidental, often within the Janos Biosphere Reserve in the state of Chihuahua.

Wolves, though, don’t always observe manmade boundaries, as in the case of a Mexican gray wolf that appeared north of Interstate 40 earlier this year near Flagstaff, Arizona. The wolf was removed by wildlife-management personnel and released in a portion of the MWEPA 200 miles to the south, only to return. Tracking data showed that as of this month, it remained well north of I-40.

For Robinson and other environmentalists, range connectivity and genetic diversity, critical factors in the survival and reproduction of a small wolf population, are jeopardized by U.S. border fencing. They also object to a U.S. policy under which wolves that are introduced into the wild in Mexico and enter the United States are removed if they are within the MWEPA. (Introduced wolves are outfitted with radio telemetry collars to track their movements.)

He cites the example of “Sonora,” a female wolf named in a contest involving school children after its saga was publicized. Introduced into the wild in Mexico with a radio collar, the wolf crossed into the United States and was seen in March 2017 in the vicinity of southeast Arizona’s Chiricahua National Monument.

Land and air search
The state’s two U.S. senators at the time, Jeff Flake and John McCain, were notified of the controversy that ensued as authorities carried out land and air searches for the wolf over several days. After locating Sonora and at one point shooting a tranquilizer dart at her and missing, wildlife personnel eventually trapped the animal, injuring her paw. Despite conservationists’ repeated appeals that the wolf be returned to the wild, Sonora remained in captivity and—apparently as a result—was ultimately deemed too accustomed to humans. She was held in a USFWS facility in New Mexico and later transferred to the Sedgwick County Zoo in Kansas.

Robinson says she has given birth to six pups since her capture, all of which were released into the MWEPA, with three of them known still to be alive in the wild. If one of them heads back to Mexico, its mother’s home turf, Robinson adds, “he will find a wall.”

USFWS’s proposed Mexican gray wolf management rules are subject to a 90-day public comment period that concludes on Jan. 27. The period includes virtual public information sessions and hearings scheduled for December 8 and January 11. Under the terms of the 2018 U.S. District Court ruling, the USFWS must issue a revised rule no later than 2022. The agency has posted the proposed rules and related information on its website.