Saturday, February 1, 2014

Wild Mexican Wolf Population Up from 2012



An annual survey by the U.S. Fish and Wildlife Service (USFWS) found that 83 Mexican gray wolves (a.k.a. lobos) and 5 breeding pairs call the wild landscape of Arizona and New Mexico home. This number demonstrates a 10% increase in the wild lobo population compared to the 2012 population count of 75.

Good news but work remains to be done.

Some History: Mexican Gray Wolf's Brush with Extinction
In the late 1800s, perhaps not realizing the ecological consequences, there was a national movement to  eradicate wolves and other large predators from the wild landscape in the United States. Wolves were trapped, shot, and poisoned.  Bounties were paid. By the mid-1900s, wild Mexican wolves had been effectively exterminated in North America.

With the only lobos remaining in captivity, the Mexican wolf was listed by the USFWS as an endangered species in 1976.  The Endangered Species Act requires the USFWS to develop and implement recovery plans for listed species with the objective to restore species to secure population levels, maintain those levels, and then remove them from the endangered list.  Shortly after listing Mexican wolves as endangered, USFWS collaborated with Mexico to capture all Mexican wolves remaining in the wild.  Five wild Mexican wolves (four males and one pregnant female) were captured alive in Mexico from 1977 to 1980, and these wolves were transferred to the United States to establish a certified captive breeding program. The objective of the plan includes the following:

“To conserve and ensure the survival of C. l. baileyi by maintaining a captive breeding program and re-establishing a viable, self-sustaining population of at least 100 Mexican wolves in the middle to high elevations of a 5,000-square mile area within the Mexican wolf’s historic range.”
 
(photo: OnEarth Magazine)
Captive-to-Wild Release Events
Mexican wolf reintroduction efforts began on March 28, 1998 when 11 captive-reared Mexican gray were released to the wild for the first time in the Blue Range Recovery Area – just a small portion of their ancestral home in the wild southwest.  Because the entire existing Mexican wolf population is derived from such a limited founding population, genetic health is the primary consideration governing both captive reproductive pairings and captive-to-wild release events. These decisions are prioritized to maintain or increase gene diversity through considerations of mean kinship, avoidance of inbreeding, and the degree of uncertainty within a pedigree.

Recovery Challenges
It’s is within the Blue Range Recovery Area that Mexican wolves have struggled for a decade and a half, failing to ever reach the initial population goal of 100, and far from reaching the population goal recommended  by the current Mexican Wolf Recovery Team’s Science and Planning Subgroup (SPS). The SPS team, scientists appointed by the USFWS Regional Director for their recognized expertise in scientific disciplines relevant to Mexican wolf recovery, recommend that a minimum of three, naturally connected subpopulations of at least 200 individuals each comprising a metapopulation of at least 750 wolves, are essential to the survival and recovery of Mexican gray wolves in the wild.

Celebrate Briefly and Get Back to Work
So while we celebrate news that the estimated wild lobo population did increase from 75 to 83, we have a long way to go until this keystone species is recovered. Artificial boundaries, state politics, illegal killings and USFWS's designation of all wild lobos as an “experimental, nonessential” population, continue to put recovery in a choke-hold.  With an estimated population of 83, the Mexican wolf remains one of North America’s most endangered mammals.



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