With 9-day-old pups tucked securely in a special backpack, Regina Mossotti hiked into the mountains in New Mexico to say goodbye to the newborns who were about to make history — and possibly a difference in the survival of their critically endangered species.
The Mexican wolves, born April 15 at the Endangered Wolf Center in Eureka, had flown with Mossotti and another helper more than 1,000 miles for their mission. The wolves, named Vida and Lindbergh, represent hope for a species with fewer than 100 individuals left in the wild.
The mission: Take the pups from their biological mother and siblings from their home in captivity in Eureka and “cross-foster” them with a surrogate mother in the wild who had given birth around the same time.
Cross-fostering can help the Mexican wolves survive by increasing the genetic diversity of the wild population. The 9-day-old Mexican wolf pups were moved from the more genetically diverse captive population and will contribute to the gene diversity of the wild population if they survive to become breeding adults.
But for it to work, there was a lot that had to line up. Placing captive-born pups into wild dens had never been tried before with Mexican wolves.
First, there was the timing. The wild and captive litters need to be born around the same time, and the transfer of pups from captivity to the wild has to occur before the pups are 10 days old, experts say. This makes the transfer easier for the pups, who still have their eyes closed and, much like other newborns, spend most of their time sleeping and eating. Then, there were the logistics. The wild den location needs to be known, a flight needs to be scheduled and weather conditions should be perfect.
The Endangered Wolf Center worked with the U.S. Fish and Wildlife Service on the effort. In New Mexico, a female wolf that was tracked with a GPS collar had stopped roaming like wolves do most of the time, and was staying in one location and then disappeared — a good indicator that she had gone down into the den and the satellite signal was no longer working. This was a clue to the Fish and Wildlife Service that she had given birth.
Mossotti and Emma Miller, an animal keeper at the center in Eureka, flew commercially to New Mexico with Vida and Lindbergh. They drove a few hours to Catron County and hiked about a mile and a half, where they met Fish and Wildlife staff to hand over the pups. The staff then hiked about another mile and half to the den to place the pups. During the trip, they fed the puppies formula.
But would their surrogate mother wolf accept them?
Placing the pups
When staff got close to the den, the mother wolf ran away. That she left her litter shows how scared of humans wolves are, said Mossotti. The mother stayed close, though, about 100 meters away, while the staff went to work.
In the den, they found five puppies. The goal was to help disguise the new puppies as the mom’s own as quickly as possible. The puppies’ escorts wore gloves the entire time they were handled to avoid transmitting unfamiliar scents. They rubbed dirt on Lindbergh and Vida, and rubbed them with their new siblings, as well as their urine, to transfer scents.
And then the staff left.
Within the hour, Lindbergh’s and Vida’s surrogate mother returned to her den. And she has stayed in the area since.
At this point, conservationists consider it a successful cross-fostering.
“Wolves are very nurturing,” Mossotti said. “They have this instinct to take care of these puppies. Fish and Wildlife Service did a great job of making sure those pups blend in with her litter.”
Wildlife staff are supplementing the pack’s natural diet by giving them elk that have been hit by cars. That supplemental food will help the foster parents take care of their new, larger litter of seven.
Once declared extinct in the wild
This could be a key point in saving the Mexican wolf, which had been hunted to the point where they were declared extinct in the wild in 1980.
The first release of Mexican wolves back in the wild took place in March 1998, with nine of the 11 wolves released coming from the Endangered Wolf Center.
The past releases were of adult wolves. While those born in captivity do well, those raised and taught to survive in the wild by a mother and father who already have a pack established have much better chances, Mossotti said.
A spokesman for the U.S. Fish and Wildlife Service in New Mexico called Lindbergh’s and Vida’s placement in the wild historic.
The service began using cross-fostering with other species as a management tool in 2014 in an effort to increase the gene diversity of the wild population.
Mossotti said getting the pups from a den in St. Louis to a den in New Mexico successfully was nothing short of exhilarating — and exhausting.
As for Lindbergh’s and Vida’s biological mom, she has taken the adoption of two of her babies well.
“She handled it great. She went back and cared for the (remaining) pups she had. She didn’t look stressed. She looked calm,” Mossotti said. “We know it’s such a vital need for the species to survive. It’s not an easy thing to do, but it’s so important.”
Lindbergh’s and Vida’s biological siblings soon will be available for viewing on the Endangered Wolf Center’s live web cam at www.endangeredwolfcenter.org/webcams.