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Wildlife Technician Explains Continued Success of Mexican Wolf Recovery

By BEN NEARY

NMWF Conservation Director

The wild population of the Mexican wolf is rising in southern New Mexico and Arizona as biologists continue to plant wolf pups born in captivity into wild dens.

This spring, the U.S. Fish and WIldlife Service announced that the 2023 wolf census found a minimum of 257 wolves, of which 144 were in New Mexico and 113 in Arizona. Those numbers show a 6-percent increase in the wolf population over 2022’s minimum total of 242 wolves. 

The increase marks the eighth consecutive year of growth, the longest continuous streak since recovery efforts began.

Pito Lopez, wildlife technician with the U.S. Fish and Wildlife Service, works on all aspects of the wolf-recovery effort. He says a big part of the job is raising public awareness of the existence of wolves and of the success of the recovery program.

Lopez will be the featured speaker at New Mexico Wildlife Federation’s free “Wildlife Wednesday” presentation at 5:30 p.m., Aug. 14, at the Marble Brewery Northeast Heights Taproom,  9904 Montgomery Blvd., NE., in Albuquerque.

“We’ll talk about all things Mexican wolf, from cross-fostering, to yearly counts to helicopter capture, to rancher relations,” Lopez said of his talk.

Lopez lives in Belen and said he commonly runs into people who are surprised to learn from him that wolves exist in the state. “And so that’s my biggest part, is to educate,” he said of the purpose of his talk. He will take questions from the audience.

The Mexican wolf had been extirpated in the United States by the mid-1900s. All the wolves alive today are descended from a base population of only seven animals that the USFWS rounded up in the 1970s – five wild wolves from Mexico and two from a zoo. Starting with such a small gene pool, restoration efforts have focused on breeding wolves that are as distantly related to each other as possible. The program has released wolves into the wild since 1998.

A key element of the ongoing wolf breeding and recovery program is “cross-fostering” – the term for introducing wolf pups that were born in captivity into a den where a wild wolf mother is raising her own pups. The program helps to improve the genetic diversity of the wild wolf population. A record 27 Mexican wolf pups were placed into wild dens this spring, according to the USFWS.

The wolf pups that were placed into wild dens this year came from six genetically diverse litters held in five different locations around the country. The pups were placed into eight wild dens in Arizona and New Mexico over four weeks starting mid-April.

This year’s placement of 27 pups brought the total number of wolf fosters to date to 126 placed into 48 wild dens, according to the USFWS. Fostered Mexican wolves have produced more than 20 litters and several of those offspring have gone on to produce pups of their own.

In addition to spreading the fostered wolf genetics across a wide area, the foster program allows the pups to learn how to live in the wild from their earliest days.

The fostering is a coordinated effort of the USFWS, the New Mexico and Arizona game and fish departments, the U.S. Bureau of Land Management, the U.S. Forest Service and the Saving Animals from Extinction Program. Project Lighthawk provides aerial support, including moving wolf pups from breeding facilities.

Biologists find the wolf dens by tracking radio-collared female wolves, Lopez said. He said the wolves breed early in the year and the females in New Mexico have been denning up in April and May.

Once a female enters the den, biologists use VHS receivers in the area where the last radio signal was recorded to locate the collared wolf in her den, Lopez said. When biologists arrive at the den, the female wolves will leave. “Wolves build dens in areas where humans and bears don’t want to go. And so a lot of times, it’s not the nicest country to be in,” Lopez said.

“Wolves are naturally afraid of human beings,” Lopez said. “In their eyes, they can go and breed another year if they survive. So every single time they run out of the den, Sometimes they run away completely and will come back later, sometimes they’ll stay up on the hill and howl and bark at us and be mad. But they’re going to run away from us when we bust into that den.”

Once the female wolf leaves, Lopez said the work of placing the pups begins. “We’ll send someone nice, small, petite into the hole,” he said. “Dens can be very deep. They can be as simple as a hole in the ground, they can be as elaborate as having several chambers if they’re reusing the den every year. And so, we’ll send up a team of two people to go up.”

The people who carry wolf pups into the go dens wear gloves and long sleeves and take other precautions to keep the scent they leave behind to a minimum, Lopez said. He said they usually will place two pups into the den, and won’t allow the number of pups in the den to exceed 10.

In addition to placing pups born in captivity into the den, Lopez said they may remove some wild-born pups for transplant into another den elsewhere.

Once wolf pups are placed in the dens, workers provide additional food in the area for a while to help the mother wolf sustain the pups. Food supplies may include road-killed elk or processed food “logs,” that are commercially made by grinding up entire animals. 

“We’re adding extra stress to them, adding cross-fosters into the den,” Lopez said of the supplemental feeding. “And so it helps alleviate the stress of having more pups in the den. You have more pup success.” 

Wolves return to the supplemental food every few days, Lopez said.  “It’s a great way to get pup counts. They bring their pups to it. We get to know whether there are still cross-fosters alive in the den.”

Workers place the food caches for the wolves and commonly set up cameras to record them. “We usually sneak in about a tenth of a mile, see if we can figure out what roads they’re using or where they’re coming in at, set up a camera, and hope they walk past it,” Lopez said. “There have been many times when I’ve had adults walk right past it and then not bring their pups down.”

Work on the wolf recovery program changes throughout the seasons.

“Right now, we are going into collaring season,” Lopez said. “We have food caches out for cross-fosters. So I’ve been doing that. So, trapping, collaring – it’s one way we’ve been able to get collars onto the wolves. It’s the safest and most effective way we can do that.”

Wolves are starting to move to rendezvous sites at this time of year, moving away from their den sites, Lopez said. He said the rendezvous sites serve as pup play areas. “So we try to find those, put a scent down so the pups get interested and come into the camera,” he said.

The wolf population generally lives in the Gila National Forest and neighboring wilderness areas and wild lands in southern New Mexico and Arizona. “All Mexican wolves are south of Interstate Highway 40,” Lopez said, adding that one pair of wolves in the Flagstaff area crosses the highway at times. In New Mexico, he said they’re generally found north of Silver City and south of Magdalena.

A large part of the wolf recovery effort involves working with ranchers. Wolves prey on livestock in addition to elk and other wildlife. There are programs to reimburse ranchers for their animals lost to wolves. Lopez said the ranchers he encounters have varying reactions to the presence of the wolf.

“There are a lot of ranchers that I work with every day, there are some that don’t work with us very well and don’t want to talk to us at all,” Lopez said. “There’s some that will let us on their private land whenever we need to, to do whatever work we need to. And so the temperament for ranchers a lot of times is that they don’t want wolves. But for the most part it’s, ‘we don’t want wolves, but we’ll tolerate wolves.’”

Lopez said the recovery effort recognizes that ranchers place a critical role in keeping forests intact and not having lands developed. “So it’s part of my job to make sure that I keep that relationship up with them,” he said.  “I think a lot of times they just want to be heard. A lot of times, just listening to them – figure out their issues and figure out ways we can help them out I think helps alleviate the hatred toward wolves.”,

Lopez said his talk will also touch on the personal importance that wolves have for him. “Wolves have always held this special place in my heart,” he said. “Especially the Mexican wolf has been this animal, without getting all spiritual about it – this animal that has always been there.”

For most of the history of the United States’ presence in the West, the government policy had been to exterminate wolves without recognizing their special place in the ecosystem, Lopez said.

Explaining his motivation to work with wolves, Lopez said,  “Working with wolves and returning wolves to that landscape, I think it drives you, you know? This is my small part in keeping the campsite clean and making sure it’s better than when I left it.”