Payson Roundup (Original) Posted March 7, 2017 by Peter Aleshire
Right now, roughly 100 Mexican gray wolves roam the wilds of Arizona and New Mexico.
From a genetic point of view, they’re almost all brothers and sisters.
And that worries the federal biologists charged with establishing a self-sustaining wild population of wolves in the Southwest.
It also largely explains the sometimes-controversial strategies the biologists are using to bolster the wild packs — and a plan to release additional wolf packs in Rim Country — hundreds of miles from the remote release sites they’ve used so far.
Biologists say the wolves face a genetic bottleneck, which will leave them prone to assorted diseases and mutations, reducing the long-term odds of their survival.
All the known Mexican gray wolves in the world are descended from the last seven of their kind captured in the wild. Those seven wolves gave rise to the captive breeding program that has produced new wolves released into the wild since 1998.
But most of the wolves now in the wild are descended from a single female, who was among the first wolves released.
The direct descendants of the matriarch of the Bluestem Pack, affectionately known as breeding female F521, dominate the wild packs.
Of the 70 wolves in the wild whose genetics are known, only four — all males — did not descend from that female founder of the line.
That means when any two breeding age wild wolves set up housekeeping — 83 percent will have both parents descended from the Bluestem Pack. The other 17 percent will have one parent descended from that fabled pack.
So that means the future success of the reintroduction program depends on continuing to introduce new genetic combinations from the captive-reared population.
Of course, that raises problems of its own.
Wild-born wolves have an instinctive fear of humans — and prefer wild prey like elk and deer to cattle and other livestock. Wolves raised in captivity, on the other hand, generally don’t avoid humans and livestock nearly as carefully.
So biologists have tried hard to rely on the growth of the wild-born population, rather than continually augmenting the wild packs with adult animals from the captive breeding program.
But that strategy has led to a genetically inbred wild wolf population.
So the U.S. Fish and Wildlife Service is now seeking public comment on the management plan for 2017, which will feature stepped up releases of carefully selected adult wolves from the captive-reared population.
In addition, biologists want to build on a so-far successful “cross fostering” program.
The cross-fostering program relies on biologists crawling into the den of a wild mother with her pups and sneaking in one or two captive-born pups of about the same age. The mother will then generally raise the two foster children as her own.
The first eight, captive pups introduced into wild dens all survived — although in every case the freaked out wolf parents moved all the pups to a new den.
“The combination of strategies outlined in this plan represent a critical and significant effort to increase gene diversity in the wild population.
“Gene diversity can continue to be improved through additional initial release and cross-fostering efforts in future years. However, it is easier to affect the gene diversity of the wolf population when it is small and will become more difficult as the population increases,” the draft of the plan concluded.
The U.S. Fish and Wildlife Service is also currently doing an analysis on a proposal to expand the area for the release of new wolf packs, which would bring the wolves to the doorstep of Rim Country.
Up until now, the wolves have been released into two wilderness areas in Arizona and New Mexico — mostly centered on the Arizona-New Mexico border near Alpine. The new release areas for both wolves released from the captive breeding program and wolves moved from wild packs would include six potential release sites in the Apache-Sitgreaves National Forests atop the Mogollon Rim — not far from the C.C. Cragin Reservoir, according to a map released with the draft report.
“These release sites are undergoing NEPA analysis by the U.S. Forest Service,” the report noted.
The report noted that the initial release of wolves from the captive breeding program requires intensive management “including supplemental feeding, monitoring and potential hazing from human-occupied areas until a period where the pack has acclimated to wild behavior. In extreme situations, the pack may also need to be removed if nuisance behaviors exceed acceptable thresholds.”
The cross-fostered wolves generally present fewer problems, since they learn how to behave in the wild and the benefits of avoiding humans altogether from their wild-born parents.
State Game and Fish officials in both Arizona and New Mexico have generally opposed expanding the recovery area for the Mexican gray wolves. The state commissions cite wolf attacks on sheep and cattle as well as their impact on elk and deer populations. Game and Fish generally relies heavily on revenue from hunting permits, especially for elk and deer. Large wolf populations can significantly reduce elk and deer populations — at least in places like Yellowstone, where wolves have thrived since their reintroduction.
The federal government will pay ranchers for livestock lost to the reintroduced wolves in Arizona and New Mexico. However, some ranchers have complained the payments don’t fully cover their losses, even when the federal biologists attribute the loss of a cow or calf to the wolves.
The ranchers generally have permits to graze on public lands, where the wolves have been reintroduced.