June 23, 2017
On Thursday, June 22 we made the difficult decision to euthanize Aztec our Mexican gray wolf. We discovered a large tumor on her front left leg on June 7th. On June 8th we brought Aztec into surgery and sent a biopsy of the tumor to the Animal Health Diagnostic Center at Cornell University. The results showed that it was a much more aggressive form of a mast cell tumor (MCT) than anticipated, with a very poor outlook on quality of life. All Mexican wolves are owned by the U.S. Fish and Wildlife Service, and managed by the Association of Zoo’s and Aquarium’s (AZA) Species Survival Plan. Utica Zoo was in contact with both organizations before the decision to euthanize was made.
Aztec was born at Stone Zoo in Massachusetts and arrived at the Utica Zoo in December of 2006. She turned 12 years old in May, with the typical lifespan for a Mexican gray wolf in captivity being 15 years, and even shorter in the wild.
The managed population of Mexican gray wolves is descended from 7 founders, with the current population at 251. Other than the reintroduced populations, Mexican wolves have not been documented in the wild since 1980. From the U.S. Fish and Wildlife Service website: “The Mexican wolf is the rarest subspecies of gray wolf in North America. Once common throughout portions of the southwestern United States, the Mexican wolf was all but eliminated from the wild by the 1970s. In 1977, the U.S. Fish and Wildlife Service initiated efforts to conserve the species. In 1998, Mexican wolves were released to the wild for the first time in the Blue Range Wolf Recovery Area within the Mexican Wolf Experimental Population Area. Missing from the landscape for more than 30 years, the howl of the Mexican wolf can once again be heard in the mountains of the southwestern United States.” For more information about the Mexican Wolf Recovery Program, please go to: https://www.fws.gov/southwest/es/mexicanwolf/
Aztec is survived by her sister Sierra. Sierra is now the lone wolf at the Utica Zoo. Mexican Grey Wolves typically live in the social structure known as a “pack”. Mexican Wolf packs are flexible structures that normally contain 2-6 individuals. However, it is not uncommon in the wild to find single individuals. These “lone” wolves are usually youngsters seeking to form a pack of their own, ostracized members no longer allowed in their pack, and sometimes last surviving members of a pair. Although not ideal to live alone, Sierra can live out her remaining years comfortably and contently. She is healthy and cared for by a staff of focused and compassionate animal care professionals who tend to her every need. Utica Zoo is working with both the U.S. Fish and Wildlife Service and the Species Survival Plan to either get a new companion for Sierra or send her to another location to be a companion to another animal in her situation. If she leaves Utica Zoo, we will likely receive a new group of wolves to live with us in the future.
Aztec and Sierra have a sister named Toluca who is currently living at the Southwest Wildlife Conservation Center in Scottsdale, Arizona. Toluca and her mate Sabio (M804) arrived as a breeding pair at the Southwest Wildlife Conservation Center in late 2015. Their previous home was at the Wolf Conservation Center in Salem, New York.