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Mexican gray wolf

Mexican Gray Wolf

Mexican Gray Wolf Conservation

“The Mexican gray wolf remains one of the most endangered subspecies of wolf in the world. Despite decades of effort to re-introduce these intelligent, family-oriented creatures into the wild, just over 80 Mexican gray wolves live in their natural habitat. That’s simply not enough to ensure the wolves will survive outside of captivity over the long-term.”

-John Linehan, Zoo New England President and CEO

Since 1998, Zoo New England has been committed to re-introducing Mexican gray wolves into the wilds of the American Southwest, where they once lived in large numbers. Stone Zoo is one of about 51 facilities across the country and in Mexico participating in the Mexican Wolf Species Survival Plan (SSP). We have overseen births of these rare animals at Stone Zoo and collaborated closely with other facilities to transfer and receive wolves on their journey to being re-introduced to the wild.


Mexicangrayfeature2The Mexican gray wolf (Canis lupus baileyi), also known as “el lobo” in Spanish, was once common throughout western Texas, southern New Mexico, central Arizona and northern Mexico. But by the mid-1900s they were eliminated from the wild in the U.S., victims of eradication efforts to prevent them from preying on livestock. They survived here only in small captive populations, and in Mexico their population also dwindled dramatically.

Great strides have been made to grow the Mexican gray wolf population and reintroduce them into the wild. In 1976, they were listed as endangered under the Endangered Species Act. The Mexican wolf recovery team was formed and a conservation and survival plan was established in 1979. In 1998, Zoo New England joined the Mexican Wolf Species Survival Plan (SSP), a consortium of institutions working together to breed the captive wolves for reintroduction and recovery in the Southwest.

Mexican gray wolves weigh between 50-80 pounds and are about 5 feet long. Their coat is often mottled or patchy and varies from gray and black to brown and buff. The wolves have complex social behavior, living in tightly organized packs, communicating through howling vocalizations, body posturing and scent marking. These animals work effectively together to adapt to most environments where there is prey, which includes deer, jackrabbit, mice and peccary.

Into the wild

Mexicangrayfeature3Since 1998, Zoo New England has participated in the Mexican Wolf Species Survival Plan (SSP) – a group of institutions including the U.S. Fish and Wildlife Service, state agencies, several zoos and other partners – all working together to reintroduce captive-bred wolves in the Southwest wilderness. We’re thrilled that the wild Mexican wolf population is slowly increasing.

Following the recommendation of the Mexican Wolf SSP, in 2011 two wolves born at Stone Zoo were relocated to facilities in Mexico. In 2012, the remaining two wolves at Stone Zoo were transferred to the Oklahoma City Zoo and Botanical Garden, which sent five male wolves to Stone Zoo in exchange. Months of careful planning and coordination amongs institutions is required to successfully manage the moves and monitor the wolves’ adjustments to their new homes.

In captivity, close bonds between wolves and keepers are avoided because, ultimately, the wolves’ survival in the wild depends on active avoidance of human contact. The animals cannot become reliant on people for food. Though wolves don't lose their natural instincts in captivity, their hunting skills need to be honed before they are released into the wild. Wolves that are slated for release are sent to large pre-release centers with some level of native prey. Typically, these wolves and their offspring are released into the wild together as a pack.

Back from the brink, slowly

MexicangrayfeatureNearly extinct by the mid-1900s, the wild Mexican Gray Wolf population is slowly coming back from the brink of extinction through the work of the Mexican Wolf SSP and other organizations.

The 55 facilities currently participating in the SSP (including Stone Zoo) house approximately 350 wolves. The SSP’s goal is to maintain at least 240 animals in captivity at all times to ensure the security of the species, while still being able to breed animals for reintroduction.

In 2020, the wild population of Mexican wolves in the United States saw its fifth consecutive year of growth. According to the recent count, the U.S. population of Mexican wolves in the wild has increased to at least 186 animals. This population has nearly doubled in size over the last five years. The 2020 survey represents not only an all-time record number of wolves in the wild, but also the most ever breeding pairs, wild packs, pups born in the wild, and pups surviving to the end of the year.

Over half of the wild Mexican wolf population is now monitored through radio collars using satellite technology to record their location. Wildlife biologists use this information to gain timely information about wolf behavior in the wild and assist with management of the wild population. In 2020, 20 captive-born pups were placed into seven wild dens (a process called “cross fostering”) to boost the genetic diversity in the wild population.

While this growth is encouraging, re-establishing the Mexican gray wolf population is a slow and complex process. For instance, a delicate balance must be maintained between re-introducing the wolves into their natural range and preventing their predation on livestock. That’s why Zoo New England is unwavering in its commitment to the future of this rarest of wolves.

How you can help

Donate to Zoo New England to help sustain our Mexican Gray Wolf conservation work.
Zoodopt a Mexican gray wolf! Zoodoption helps us provide excellent food, care and enrichment for all of our animals.