Serving the High Plains
Serving the High Plains
Captive-born Mexican wolf pups are mixed together with wild-born pups before being placed into a wild den.
At least three Mexican wolf pups once in captivity have been successfully cross-fostered into wild packs in New Mexico this year.
The Mexican Wolf Interagency Field Team captured and placed radio collars on seven of this year's cross-fostered wolf pups, a record success for the program.
The Mexican wolf remains the rarest subspecies of gray wolf in North America.
Last spring, members of the field team and the Mexican Wolf Species Survival Plan cross-fostered 20 genetically diverse wolf pups from captive facilities into litters of wild wolf packs.
The team reported:
• One of two pups cross-fostered from the Phoenix Zoo to the Iron Creek pack in New Mexico has been caught and radio-collared;
• One of two pups cross-fostered from the Endangered Wolf Center in Eureka, Missouri, to the San Mateo pack in New Mexico has been caught and radio-collared;
• One of the four pups cross-fostered from the Endangered Wolf Center to the Dark Canyon pack New Mexico has been caught and radio-collared.
Four of seven pups cross-fostered from zoos or endangered wolf centers to two packs in Arizona also were caught and radio collared. One of those wolves was found dead this month, however.
In 2019, the Mexican Wolf Interagency Field Team captured and collared two of the 12 pups cross-fostered into the wild. The team has documented that cross-fostered pups have the same survival rate as wild-born pups during their first year of life, about 50%.
"We have documented survival in four out of the seven packs that received cross-fostered pups this year - and there could still be more. This is an extraordinary accomplishment by our field team," said John Oakleaf, Mexican Wolf Field Projects coordinator for the U.S. Fish and Wildlife Service.
Cross-fostering is a proven method used by the team, which uses federal, state and tribal partners, to increase genetic diversity in the wild Mexican wolf population. It involves placing genetically diverse pups less than 14 days old from captive breeding populations into wild dens with similarly aged pups to be raised as wild wolves.
Since 2014, 50 genetically diverse wolf pups have been cross-fostered into the wild. Five cross-fostered wolves have survived to breeding age, resulting in litters of genetically diverse pups born in the wild. There are 14 genetically valuable cross-fostered wolves that are collared and alive in the wild the team is monitoring, and additional cross-fostered wolves very likely are alive in the population that have not been captured and collared.