Mexican Gray Wolf

Conservation Story

ALL PHOTO CREDIT: WILLIAM R. DRIVER

Arizona's Endangered Mexican Wolves

Arizona Game and Fish Department

Natural History

Not Your Average Wolf


  • Mexican wolves, or Mexican gray wolves, are the smallest and most genetically distinct subspecies of gray wolf.
  • While about 30 subspecies of gray wolves are found across North America, Europe, and Asia, the Mexican wolf is only found in the American Southwest and Mexico.
  • Like most wolves, Mexican wolves usually live in packs with a dominant breeding pair and offspring from several litters.
  • Their packs are smaller than other subspecies, usually around 4-8 wolves.
  • They communicate through howling, growling, barking, and scent markings.
  • Females will usually give birth to 2-6 pups in late spring in their den.
  • Mexican wolves eat deer, elk, javelina , and will occasionally scavenge.

 

So, What's the Problem?

In the 1900s, human settlement expanded into the American Southwest and Mexican wolf habitat. As humans arrived, populations of Mexican wolves began facing problems.

1

Livestock

As settlers moved into the Southwest, they brought along their herds of livestock. Their large herds of cattle and other species required huge amounts of land for grazing, which damaged the ecosystem. The livestock overgrazed huge portions of land leaving little resources for the native herbivores and pushing them out of regions they were previously plentiful.

2

Prey Base Depletion

While the settlers did bring livestock and other resources with them, they also hunted the native deer and elk, further decreasing the food resources for the wolves. With their prey base heavily depleted, wolves turned to the livestock for an easy meal, enraging the settlers. 

3

Retaliatory Hunting

As wolves found a new source of food in livestock, ranchers and others who depending on their livestock for food or to make a living fought back. While some took removing the wolves into their own hands through hunting, others used petitions and successfully pressured the US Biological Survey (now the USFWS) to hunt, trap, and poison predators in livestock regions. 

Between 1915 and 1925, nearly 1,000 wolves were reportedly killed in Arizona and Ne w Mexico.

While Mexican wolves tried to re-establish breeding populations and territories in the US for the next several decades, they were unsuccessful due to constant eradication pressures.

The last Mexican wolf in the US was killed in 1970.

A World Without Wolves

By the 1970s, Mexican wolves had become functionally extinct in the US and Mexico.

Without wolves, ecosystems change dramatically. Populations of grazers, like deer and bison, grow very quickly without wolves to keep their numbers in check, which results in the landscape being overgrazed. Removing wolves from an ecosystem often results in a trophic cascade, or a series of changes throughout the food web that altering the ecosystem. Learn more about trophic cascades in the video below!

In 1973, the Endangered Species Act was passed to protect habitats and species whose populations were being threatened with extinction. While there was most certainly controversy, the Mexican wolf was listed under the ESA in 1976.
How Wolves Change Rivers

RECOVERY PROGRAM

Between 1977 and 1980, remaining Mexican wolves were captured in Mexico and became the foundation for a bi-national captive breeding program. The captive breeding program began with 7 wolves.
The Mexican Wolf Recovery Plan was created in 1982. It expressed concern of never being able to delist the Mexican wolf due to the challenges of re-wilding captive-born pups.
The initial goal of the Mexican Wolf Recovery Plan was to establish a population of 100 wolves in a 5,000 square mile area within their historic range.
As the captive breeding program became more successful, researchers worked to declare a suitable reintroduction region. A portion of the Blue Range Wilderness between Arizona and New Mexico was selected for their recovery area.
Strict regulations were put in place before reintroduction to better monitor and deal with wolf conflict in the reintroduction area.
On March 29, 1998, 11 captive-born Mexican wolves were released into the recovery area.

Mexican Wolves Today

2019 Population Survey

In 2019, the wild population of Mexican wolves in the United States has risen to 163 individuals, a 24% increase from 2018. The survey showed a minimum of 42 different packs and that 90 Mexican wolf pups were born, with 52 surviving the year. According to the Center for Biological Diversity, more than 30 Mexican wolves are living in Mexico as of early 2018. In captivity, more than 300 Mexican wolves belong in the captive breeding program in 50+ facilities. 

Wild Wolf Boot Camp

Most Mexican wolves that have been reintroduced to the wild are adults, which can sometimes be problematic. Wolves raised in captivity are often more comfortable around people and have not grown up learning how to hunt and protect themselves the way wild wolves do. To help reduce human-wildlife conflict and give the reintroduced wolves the best chance for survival, they go to boot-camp prior to release. At boot camp, they observe the wolves to make sure there are no physical or behavioral problems and select wolves based on genetics, physical and reproductive health, and overall response to the adaptation process.

Thinking Outside of the Box

Historically, only captive-born adult wolves had been released as part of the reintroduction program. In 2014, biologists took newborn pups and placed them in a wild den with a newborn litter born at roughly the same time as the captive-born pups in a process called cross-fostering.  These cross-fostered pups are raised by wild parents and have a higher chance of survival while also adding new genetics to the wild wolf population. Since 2014, more than 30 Mexican wolf pups have been cross-fostered into wild dens.

Ongoing Conflict

Predator eradication efforts might sound like an archaic concept from time long past, but unfortunately, the conflict that was present in the early 1990s is still present. As the Mexican wolf population recovers and expands, ranchers' livestock are at risk of depredation and many are willing to take matters into their own hands. Additionally, policymakers have quietly allowed the private and federal killing of Mexican wolves as recently as the summer of 2020.

Do Your Part for Wolves

Use Your Voice (Or Pen...)

Don't just tell your friends why wolves are important, tell policymakers. Call, email, or write to USFWS, AZGFD, & NMDGF to tell them you're with the wolves and you support the ESA and wolf conservation!

Responsible Hunting

Responsible hunting is important for all species of predators because it maintains their prey base and the landscape. Hunting at the appropriate time of year and in regulated locations ensures pregnant or nursing females are not hit and prey populations are not eradicated in entire regions.

Donations

Other than donating your time to reach out to policymakers, you can donate financially to the California Wolf Center, Lobos of the Southwest, or any of the 50+ zoos and other facilities with a Species Survival Plan for Mexican wolves.

Keep Learning!

2019 Population Survey | USFWS

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Mexican Wolf Dashboard | USFWS

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ALL PHOTO CREDIT: WILLIAM R. DRIVER