SILVER CITY, N.M.— The U.S. population of endangered Mexican gray wolves grew by 32 animals, from 131 in 2018 to 163 in 2019, according to a U.S. Fish and Wildlife Service census announced today. The numbers represent a 24% increase — the largest increase since 2014. Nineteen packs had pups alive at the end of the year.

Eighty-seven of those animals were in New Mexico and 76 in Arizona.

“This increase represents countless moments of wolf vigilance and smarts in avoiding people, which is a big part of keeping their precious pups alive,” said Michael Robinson with the Center for Biological Diversity. “It’s heartening to have more wolves in our forests, but federal officials need to take much stronger action to establish healthy genetic diversity.”

Last year 12 captive-born wolf pups were released to the wild to be raised by unrelated wolves. This attempt aimed at sharing the more diverse captive population’s genes with the genetically impoverished wild population. Only two of the 12 pups are known to have survived.

If those two pups survive to age two and successfully reproduce, their pups will be significantly less inbred than almost every other wolf in the population.

Despite releases of 30 captive-born pups from 2016 through 2019, just seven are known to have survived. Inbreeding in the population has worsened each year.

The Fish and Wildlife Service refuses to release pairs of well-bonded adult wolves with their pups — family packs — from captivity into the wild. Such releases established the existing wolf population and have a much higher success rate than separating pups from their mothers for release. The livestock industry-dominated Arizona Game and Fish Department’s opposition to family releases halted the practice after 2006.

The Center for Biological Diversity advocates for resuming the releases of family packs of wolves from captivity to the wild to reduce inbreeding. The wild population of Mexican wolves in the United States was established beginning in 1998 through the successful releases of family packs.