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What You Need To Know

The Mexican Gray Wolf

Updated: March 13, 2017
Mexican gray wolf. (Mark Dumont / CC BY-NC 2.0)

A guide explaining how canis lupus baileyi became one of the most endangered mammals in North America—and how it can be saved from extinction.

What is a Mexican gray wolf, and how is it different from a gray wolf?

  • Mexican wolf on the Sevilleta National Wildlife Refuge.
    Jim Clark / U.S. Fish & Wildlife Service
    Mexican wolf on the Sevilleta National Wildlife Refuge, New Mexico. Download image.
  • Mexican wolf pack howling at Sevilleta Wolf Management Facility.
    U.S. Fish & Wildlife Service
    Mexican wolf pack howling at Sevilleta Wolf Management Facility. Download image.
  • Mexican wolf pup.
    U.S. Fish & Wildlife Service
    Mexican wolf pup. Download image.
The Mexican gray wolf (Canis lupus baileyi)—the “lobo” of Southwestern lore—is the most genetically distinct lineage of wolves in the Western Hemisphere.
At only 25–32 inches tall, the Mexican gray wolf is smaller than its cousin, the gray wolf (Canis lupus) of the northern Rocky Mountains and the Pacific Northwest.
Mexican gray wolves have historically lived across the southwest of the U.S. and Mexico. They have a distinctive, richly colored coat of buff, gray, rust, and black, and they often have distinguishing facial patterns.
Like their cousins, Mexican wolves live in packs with a complex social structure and an intricate communication system. Their howl is an iconic symbol of the West.

How many Mexican gray wolves exist in the wild today?

Mexican gray wolves once numbered in the thousands throughout the southwestern U.S. and Mexico, but with the arrival of the livestock industry, ranchers and government agents nearly silenced this important predator with rifles, traps, and poisons.
Now there is only a single Mexican gray wolf population that lives in the mountains of central Arizona and New Mexico.
As of the most recent count in February 2017, the sole wild Mexican gray wolf population had only 113 wolves, making it one of the most endangered mammals in North America.
Map by U.S. Fish & Wildlife Service
The occupied range of the Mexican gray wolf. View larger map

Why is the Mexican gray wolf population still so small?

  • A Rocky Road to RECOVERY

    With only 113 left in the wild, the Mexican gray wolf (Canus lupus baileyi) has faced many hurdles on its path to recovery …

  • A DWINDLING EFFORT

    The service controversially designates the lobos a nonessential experimental population, which allows for the “take”—shooting, trapping, capture, or harm—of wolves in the wild.

  • A HOWL OF HOPE

    In 2014, Earthjustice sues the service for its more than 30-year delay to develop a valid recovery plan.

The Mexican gray wolves were all but eliminated from the wild in the U.S. by the early 1970s, and the U.S. Fish and Wildlife Service listed the Mexican gray wolf as endangered in 1976.
By 1980, the wolves were heading toward extinction in Mexico as well, and between 1977 and 1980 the U.S. Fish and Wildlife Service and its Mexican counterpart captured the last known Mexican gray wolves in the wild. These last survivors of the wild population became the founders of a captive-breeding program designed to increase and enhance the population’s genetic diversity and prevent the wolves’ extinction.
U.S. Fish & Wildlife Service
Aspen Pack, 2005 translocation. Download image.
In 1998, the service reintroduced a small population into the wild made up of members that were bred from just seven captive wolves from this program. Every wild lobo that exists today is a descendent of those seven wolves.
Today, the wild population remains on the brink of extinction, threatened by both illegal and legal killings. The February 2016 count found that escalating mortalities and illegal killing, along with reduced pup survival, reduced the wild population by 11 percent from the previous year.
But there’s more to the story than just the numbers: the population’s poor genetic diversity may be the biggest threat facing the wolves. To remedy this, the service must release more wolves into the wild.

Why is it bad if these wolves go extinct?

There is an ethical and moral dimension to the loss of an entire species due to human impact. Also, the loss of a top predator can have cataclysmic impact on the health of the entire ecosystem. This was witnessed in Yellowstone after the extirpation of wolves in the Rocky Mountains in the early 20th century.
U.S. Fish & Wildlife Service
Dark Canyon Pack, July 31, 2014. Download image.
The loss of the linchpin predator disrupted food webs and set off a phenomenon called a “trophic cascade,” in which the wolves’ natural prey (in this case, elk) multiplied and consumed unsustainable amounts of native vegetation.
When wolves were returned to the park, they kept the elk population in check and changed the prey’s behavior. The herbivores started to avoid riparian areas in valleys and gorges where they could be easily hunted by predators. As a result, these ecologically important areas began to regenerate and species such as birds, beavers, mice, and bears returned.
Many believe that the return of the lobo’s population to healthy levels would have a similar beneficial impact on the ecosystem of the Southwest.
Here’s how the death of one wolf in Arizona changed one of the West’s earliest environmental leaders:

“We reached the old wolf in time to watch a fierce green fire dying in her eyes. I realized then, and have known ever since, that there was something new to me in those eyes—something known only to her and to the mountain. I was young then, and full of trigger-itch; I thought that because fewer wolves meant more deer, that no wolves would mean hunters’ paradise. But after seeing the green fire die, I sensed that neither the wolf nor the mountain agreed with such a view.”

– Aldo Leopold, A Sand County Almanac, 1949

What specifically does the Endangered Species Act require?

The Endangered Species Act is one of the most popular and important environmental laws. Among other things, it requires the Fish and Wildlife Service to “conserve” all listed species to the point that they no longer need the protection of the Act; in other words, the service must “recover” the species in the wild.
It also requires the service to develop recovery plans based on the best available science that provide a blueprint with strategies and benchmarks that ensure the species achieve recovery.
Once listed, species may not be killed or harassed, and in most cases, their habitats must be protected.

What protections does the Mexican gray wolf have now under the Endangered Species Act?

U.S. Fish & Wildlife Service
M636 at Sevilleta Wolf Management Facility. Download image.
The Mexican gray wolf is managed with less protection than most endangered species because it is an “experimental population.”
This means that Fish and Wildlife Service may manage the wolf under relaxed rules that allow wolf "take"—killing, harassing, or damaging habitat necessary for the survival and recovery of the species—that is usually barred by the law. The service did this because it believed—wrongly, as demonstrated by the significant amount of illegal wolf killings—that this approach would cause opponents to accept the wolf.
The service released the most recent rule governing Mexican gray wolf management in January 2015, and Earthjustice challenged it due to major flaws that would handicap the wolves’ chances for recovery. These flaws include limiting the wolves to a single population of just 300–325 individuals, preventing them from roaming broadly into necessary recovery habitat, and allowing for excessive killing of wolves at the behest of ranching or hunting interests.

It’s been 40 years since Fish and Wildlife Service listed the Mexican gray wolf as federally endangered. Why hasn’t the lobo recovered?

The lobo continues to struggle for survival because the Fish and Wildlife Service has for decades bowed to intense political pressure from state fish and game agencies whose hunting constituents perceive the wolf as an unwelcome competitor for deer and elk. The politically powerful ranching industry has also pressured the service to not adopt conservation measures like reintroducing more wolves into the wild that would benefit the wolves and increase their chances for recovery.
U.S. Fish & Wildlife Service
F511 at Sevilleta Wolf Management Facility. Download image.
As a result, the service’s track record on restoring this iconic animal to the wild under the Endangered Species Act has been marred by years of delay and false starts, leaving the wolf on the brink of collapse four decades after it was listed as endangered.
One of the seminal obstacles to wolf recovery is the service’s failure to develop a valid recovery plan. Such a plan, which is mandatory under the Endangered Species Act, is essentially a blueprint for rebuilding an endangered species’ population to sustainable levels, and it is critical to ensure the lobos’ survival.
Instead, the service’s wolf management has limped along based on an insufficient stopgap plan devised in 1982. The service has admitted that the plan was incomplete, intended for only short-term application, and “did not contain objective and measurable recovery criteria for delisting as required by [the Endangered Species Act].”
The good news is a recent court settlement will require the service to prepare a long-delayed recovery plan for Mexican gray wolves by November 30, 2017.

What does a valid recovery plan provide?

A recovery plan outlines specific conservation strategies, timelines, and benchmarks that the Fish and Wildlife Service will achieve in order to recover the species. The plan is based on the best available science.

What happens now that the Fish and Wildlife Service has a hard deadline for completing a recovery plan?

In the settlement agreement, the service will be required to complete a recovery plan by November 30, 2017, that includes a peer review by respected experts and mandatory periodic status reports so we can keep track of progress and identify any emerging issues.
It is the service’s duty to convene a top-notch recovery team, follow the science, and not let politics corrupt the final decision. (Read the settlement.)

What else does the Mexican gray wolf need in order to rebound to a healthy population?

The service’s most recent recovery team of wolf experts has done extensive, rigorous work to determine what needs to be done to save the subspecies. Their work to date amounts to the best available science on the wolves’ recovery needs.
U.S. Fish & Wildlife Service
M1051 with four pups. Download image.
The team concluded that survival required the establishment of wolves in at least three populations located in the current area of occupation in the mountains of central Arizona and New Mexico, and also in the Grand Canyon region and in the southern Rockies of southern Colorado.
Further, the team concluded that instead of a population of just a few hundred wolves, the total wolf population must grow to at least 750 individuals, and those individuals need to live in the three population centers that would be linked to facilitate genetic exchange.
Expert scientists have called the current wild population a “genetic basket case in need of serious genetic rehab. Failing to do so is irresponsible and also managing for extinction.” The service must act without delay to complete both a recovery and a management rule that ensure the wolves’ survival.

Where is suitable habitat for the Mexican gray wolf located?

Habitat capable of supporting the two additional populations needed for Mexican gray wolf recovery exists in the Grand Canyon ecoregion and in northern New Mexico/southern Colorado.
The service’s most recent recovery team drafted a plan in 2012 that called for establishing three interconnected Mexican gray wolf populations totaling at least 750 animals in these areas, but the service abruptly abandoned the planning process before a plan could be finalized.

But these wolves were never historically in Colorado. Why should they be allowed there now?

Scientists have found that Mexican gray wolves lived in Mexico, Arizona, New Mexico, and west Texas before roaming as far north as Colorado where they intergraded with other wolf subspecies.
However, wolf recovery efforts are not limited by the boundaries of its historic habitat; the Endangered Species Act requires recovery of the species in the wild and does not limit recovery to historic habitat. Climate change means historic habitat may no longer support recovery and the ranges of many species may shift northward.

Do these wolves kill livestock?

Occasionally. Native prey for Mexican gray wolves includes elk, mule deer, white-tailed deer, javelina, rabbits, and other small mammals. Mexican wolves can and do occasionally kill livestock, particularly young animals, though the overall number of livestock killed by Mexican wolves is small. A report found that in 2012, when there were 75 wolves in the designated recovery area, wolf depredation accounted for just 0.1% of all the cattle in that area. Mexican wolves also readily scavenge on carcasses of prey species.

What about deer and elk?

Arizona Game and Fish says there has been no discernible impact on deer or elk populations since Mexican gray wolves were released in wild.

What is Earthjustice doing to help the Mexican gray wolf?

Earthjustice has two active cases to help defend the Mexican gray wolf:
Forcing the Service to Complete the Long-overdue Recovery Plan: The first, filed on behalf of Defenders of Wildlife, the Center for Biological Diversity, the Endangered Wolf Center, the Wolf Conservation Center, and retired Mexican Wolf Recovery Coordinator David R. Parsons, is a challenge to the Fish and Wildlife Service’s failure to produce a valid recovery plan for the wolf.
Earthjustice attorneys negotiated a settlement agreement that requires the service to complete the required recovery plan by November 30, 2017. Papers requesting the court's approval of the agreement were filed on April 26, 2016.
U.S. Fish & Wildlife Service
One of five pups in the Iron Creek Pack observed during June, 2015. This pup is about 7 weeks old. Download image.
Getting an Effective Rule to Manage Wolves on an Ongoing Basis: In the second case, Earthjustice, on behalf of Center for Biological Diversity and Defenders of Wildlife, is challenging provisions of the federal government’s rule governing the service’s management of Mexican gray wolves. The federal rule the service published in early 2015 makes some positive changes, including increasing the range of the species, but it also has some poison pill provisions that will ultimately doom any chance of survival of the wolf. Earthjustice is challenging these flawed aspects of the rule including an arbitrary cap on the number of wolves allowed in a specified management area, limits on the areas in which the wolf will be allowed to roam, and the permission for wolves to be killed in unjustifiable circumstances and with insufficient oversight. This case is being briefed.
In the end, Earthjustice seeks to require the service to adopt an approach to Mexican gray wolf recovery that honors the best available scientific information so that the lobo of southwestern lore can survive and flourish as a living, breathing part of our nation’s natural heritage. Timeline of Legal Cases
Media Inquiries:

Maggie Caldwell, Advocacy Communications Manager
(415) 217-2084, mcaldwell@earthjustice.org

Is there anything I can do to help?

The governors of Arizona, New Mexico, Utah and Colorado, bowing to pressure from ranchers and anti-wolf interests, are fighting to undermine recovery efforts. Political pressure should not interfere with a science-based recovery plan.
The Fish and Wildlife Service and the Department of Interior needs to hear that you support a recovery plan that is based on sound science and that ensures the survival of Mexican gray wolves in the wild. Send your message.

More About Earthjustice's Legal Work on Wolves