ALBUQUERQUE (AP) – There are now more Mexican gray wolves roaming the American Southwest than at any time since the federal government began reintroducing the endangered predators.

An annual survey by the U.S. Fish and Wildlife Service shows at least 109 wolves are spread among forested lands in southwestern New Mexico and southeastern Arizona.

The population is more than double what it was in 2010. Last year, the survey turned up at least 83 wolves.

Fish and Wildlife Service Regional Director Benjamin Tuggle described the increase as a monumental milestone that resulted from management changes over recent years and more social tolerance for the animals.

He says the population is made up entirely of wolves born in the wild.

A subspecies of the gray wolf, the Mexican wolf was added to the federal endangered species list in 1976.