Conservationists are celebrating a surge in numbers for Mexican grey wolves whose wild population in the US continues to “grow at a healthy pace,” according to the U.S. Fish and Wildlife Service (USFWS). The results of a recent census show that populations of the endangered canids in New Mexico and Arizona grew by 24 percent last year bringing the total number of wolves in the wild to 163 individuals.

Mexican gray wolf (Canis lupus baileyi). Image © U.S. Fish and Wildlife Service

“The count shows we have more wolves, more breeding pairs and more pups born in the wild than ever before,” Amy Lueders, Regional Director for the U.S. Fish and Wildlife Service in Albuquerque, New Mexico explained in a press release. "This is the second year we have seen a significant increase in the wild population of Mexican wolves, a success that is directly tied to the science-based, on-the-ground management efforts of the Interagency Field Team [IFT]."

The IFT is a multi-disciplinary task force put in place to monitor Mexican wolf numbers. Between November 2019 and January 2020, the team conducted extensive ground counts of wolves before finishing off their tally with aerial surveys in January and February this year. At least 21 of the 28 packs that the IFT were monitoring in the spring of 2019 had pups, and no fewer than 52 of the youngsters (from a total of 90 born) survived until the end of the year. That’s a survival rate of 58 percent – just above the 50-percent average.

Mortality rates were also lower in 2019 with only 14 deaths recorded – a 33 percent decrease compared to the previous year.

Grey wolves have a lengthy history of persecution, largely at the hands of ranchers who kill the predators to avoid livestock losses. The Mexican grey wolf – the rarest subspecies of the more common grey wolf – was all but eradicated from the American Southwest nearly 50 years ago, triggering efforts by conservationists to save the imperilled species.

USFWS began working with the Mexican government on a captive breeding program in 1977. It would be over 20 years before the team were finally able to release 11 wolves onto a stretch of protected land in Arizona and New Mexico. Since then, the population has steadily increased alongside careful monitoring and further introductions. The recovery of the species, however, has not been seamless with many ranchers pushing back against efforts to save the wolves, and government policy generally coming up short.

This video is a summation of a longer piece put together for Earth Touch by Amy Matthews Amos in 2018 (Read the full article here):

In 2019 – as part of a conservation initiative called "cross fostering" – 12 captive-born pups were placed in wild dens to help boost genetic variability. Since their release, two of these pups have been captured and collared and efforts continue to document the remaining youngsters. Since the cross-fostering project began five years earlier, nine pups have survived and been recruited into wild populations. Four of them have reached breeding age resulting in "multiple litters of genetically diverse pups born in the wild," USFWS explained in a statement.

“The results of this census are very important as they reflect the great progress being made in the recovery of the Mexican wolf in the United States. The increase in the Mexican wolf population is not an isolated year, but rather a continuum of increases over the last 10 years,” according to Jim deVos, Assistant Director of Wildlife Management for the Arizona Game and Fish Department.

Conservationists are hopeful that cross-fostering and careful monitoring will continue to help boost both numbers and genetic diversity in the slowly growing population of these endangered canids.


Top header image: USDA Forest Service