Progress of the Mexican Wolf Recovery Program

Interagency Field Team (IFT) 
Mexican gray wolf activities are monitored by the Interagency Field Team (IFT).  The IFT is co-lead by five agencies: Arizona Game and Fish Department, U.S. Fish and Wildlife Service, White Mountain Apache Tribe, USDA Animal and Plant Health Inspection Service, and USDA Forest Service. The team includes field team leaders (one per state and tribal lead agency), wildlife biologists and specialists, depredation specialists, conservation education and outreach specialists, field assistants, as well as interns and volunteers.  The IFT is responsible for tracking and monitoring the wolves, recording their location and behavior, responding as necessary when issues develop, drafting annual work plans, annual performance reports, and any new or revised Mexican Wolf Recovery Program operating procedures.  

Population
After the initial release, the three packs established territories and by the first summer Arizona’s first wild-born wolves in more than 50 years were living in dens in the recovery area.  By 2005, the need to release wolves born and raised in captivity had diminished, and by 2010 nearly all wolves in the wild were wild born.  As of population monitoring in 2013, at least 83 wolves were counted roaming in Arizona and New Mexico.  This is an increase from 75 in 2012 and the highest since the start of the recovery program.  In the captive breeding program, the number of Mexican wolves was between 250 and 300 wolves as of 2013.
 

Genetic Diversity
The entire Mexican gray wolf subspecies today descends from only seven animals.  One of the principles of genetics is that the more diverse a species is the greater its likelihood of long-term survival.  A small gene pool can lead to perpetuation of harmful genes if they are present in the small population.  In order to optimize genetic diversity among the Mexican gray wolf population, individual wolves are selected to breed based on their known DNA sequence.  Effects of inbreeding in wolves can include a decrease in litter size and smaller pups.

Diet
Based on scat analysis, 80-90% of the Mexican gray wolves diet is elk (Cervus Canadensis).  On average, one wolf consumes the equivalent of about 16 adult elk per year.  Secondary food sources include deer (mule deer, Odocoileus hemionus, and Coues’ white-tail deer, Odocoileus virginianus couesi), bighorn sheep (Ovis canadensis), and livestock.  With livestock, there have been about 25 confirmed depredations per 100 wolves per year.  

Telemetry
Radio telemety collars are worn by 55% of Mexican gray wolves in the wild.  The collars capture a wide variety of information about the wolves, including home range, denning locations, depredations, depredation behaviors, and dispersal patterns.  Telemetry signals are monitored from the ground using a radio receiver, map, and compass.  Telemetry signals are also monitored by helicopter during the yearly population monitoring of the wolves. 

Identifying denning locations can help avoid depredation events on livestock.  When the Mexican gray wolf is denning, the animals tend to stay close to their dens.  If livestock are in nearby pastures, they become targets of depredation.  Telemetry collars allow the IFT to identify denning areas and move livestock as necessary to avoid interactions.
 

Wolf Mortality and Relocations
Between 1998 and 2012, the IFT has documented 92 Mexican gray wolf mortalities in the wild.  Forty seven deaths were due to illegal shootings and eighteen were from natural causes.  Other causes of casualties include vehicle collisions, taking animals with repeated livestock depredations or interactions with humans, and miscellaneous reasons (snakebite, mountain lion, infection, dehydration).

Also, between 1998 and 2012, twenty eight wolves were removed from the wild either lethally or taken into captivity for excessive livestock depredations or exhibiting nuisance behavior.  Nuisance behavior includes a lack of fear of humans and regularly visiting residential areas.  Some of the wolves that were removed were eventually returned to the wild when the animals were older.
 

References

  • Private Individuals using Telemetry Equipment - Allows non-agency individuals to monitor wolf activities near livestock or private property.
  • Wolf Mortality - Causes of documented Mexican wolf deaths in the Blue Range Wolf Recovery Area, Arizona and New Mexico, 1998-2013. Management-related permanent removals, including lethal control, are not included in this table.
  • Initial Releases and Translocations - Initial releases (wolves born in captivity with no previous wild experience) can only occur in the primary recovery zone in Arizona.  Translocations (previously released wolves or wolves born in the wild) can occur in the primary or secondary recovery zones.  Wolves are not allowed to establish territories on public lands completely outside the Recovery Area boundary and are retrieved.
  • Images of Wolves in the Blue Range Wolf Recovery Area and Captive Breeding Program
     

Studying Mexican Wolves
A four month old wild-born pup is captured, fitted for a GPS collar, vaccinated, and released back into the wild by biologists. This video was produced by the Information Branch of the Arizona Game and Fish Department.

Wolf Release 
A pair of Mexican gray wolves were released into the Blue Range Wolf Recovery Area on April 9, 2014.  The male was captured during the annual wolf population survey and the female is from the captive breeding program.  The pair was held through the breeding season at the Sevilleta Wolf Management Facility in New Mexico and it is believed the female is pregnant.