Mexican gray wolves boost their numbers, but a lack of genetic diversity remains a threat
ALBUQUERQUE, N.M. — The wild population of Mexican gray wolves in the southwestern US continues to grow, but environmental groups warn that inbreeding and the resulting genetic crisis within the endangered species will continue to threaten its long-term survival.
The warning came Tuesday as the U.S. Fish and Wildlife Service and wildlife agencies in Arizona and New Mexico announced the results of an annual survey that showed at least 257 wolves roaming parts of the two states. That’s 15 more than the year before and the most reported in the wild since the reintroduction program began more than 25 years ago.
Although this is the eighth year in a row that the population has increased, environmentalists say the higher numbers are not necessarily a positive development. They argue that this only means that the genetic crisis among Mexican gray wolves will become harder to solve as the population grows.
“Agencies will argue that this new benchmark shows a path to success, but it does not measure the indicators of genetic diversity that need to be addressed with improved adult and family release policies,” said Greta Anderson, deputy director of Western Watersheds Project. said in a statement.
Environmental groups have been pushing for years for the federal government to release more captive wolves into the wild and to revise policies that limit the population to boundaries they see as arbitrary. Currently, wolves that wander north of Interstate 40 in both states are captured and either returned to the Wolf Recovery Zone or placed in captivity, where they may be matched with potential mates.
Federal and state wildlife officials who have worked to restore Mexican wolves in the Southwest argue that genetic management using captive pups is getting results. Since 2016, nearly 99 captive-born pups have been placed in 40 wild dens to broaden the genetic pool.
According to the study, at least 15 wolf pups reached breeding age in the past year, and at least 10 raised wolves have successfully bred and produced litters in the wild.
“The fact that Mexican wolves have been bred, survive, disperse, mate, breed and start their own packs tells us that fostering works,” Brady McGee, the Mexican wolf recovery coordinator for the U.S. Fish and Wildlife Service, said in a statement.
Michael Robinson, a senior conservation advocate at the Center for Biological Diversity, said most of the pups placed in wild dens have disappeared over the years and at least a dozen have been found dead. Although the captive population retains some genetic diversity, he said each Mexican gray wolf in the wild is almost as closely related to the next as siblings.
Robinson said the Fish and Wildlife Service’s artificial feeding of wild wolves has increased the animals’ fertility and pup survival without solving underlying inbreeding. Wildlife managers sometimes use supplemental food supplies for the first six months for packs with foster pups.
He and others renewed their push Tuesday to release more captured wolf families, saying success would be greater.
Ranchers and other rural residents have opposed more releases, saying their livelihoods have been threatened by the wolves’ continued killing of livestock.
While compensation funds help alleviate some of the financial hardship that comes from killing their livestock or the costs of materials and labor to set up deterrents, they say this is often not enough and that federal standards adopted last year to determining whether livestock were killed by wolves will make it more difficult to obtain compensation.
New Mexico lawmakers included $1.5 million in their budget proposal to support existing offset efforts over two years, starting next year. Democratic Gov. Michelle Lujan Grisham has until Wednesday to sign the budget and other legislation passed during the just-concluded 30-day session.