This past July, the Chicago Zoological Society hosted the bi-national planning meeting for the Mexican wolf population, which was attended by colleagues from the United States and Mexico. During the three-day meeting, representatives from various organizations, including the U.S. Fish and Wildlife Service (USFWS) and the Association of Zoos and Aquariums (AZA), identified breeding recommendations for the current population and potential wolves for future release to the wild.

They also discussed cross-fostering efforts, and participation in reproductive studies to sustain populations both in the wild and professional care.It was determined all 10 Mexican wolves at Brookfield Zoo would be sent to other facilities this month, with the exception of a 2-year-old female named Ela, who would stay at the zoo and become the new alpha female. A new male, scheduled to arrive before the end of 2018, will be introduced to Ela. The two will become the new breeding pair at Brookfield Zoo.

“We are sad, like I’m sure many of our guests will be, to see the current wolf pack leave. However, the moves will benefit the recovery program for the species in the long run,” said Joan Daniels, curator of mammals for the Chicago Zoological Society. “We are hopeful for a successful introduction between Ela and her new mate and look forward to them raising their own pups in the future.”

The current wolf pack at Brookfield Zoo is comprised of three generations (litters born in 2016 and 2017) along with two cross-fostered wolves, Springer and Mateo, introduced to the pack in 2017. It is one of the largest and most successful packs in the program currently. However, the young animals need new homes, as they are now mature. Young wolves normally disperse from their natal pack at 2-3 years of age. Because Brookfield Zoo has been successful with multiple pup births, the AZA’s Species Survival Plan for the Mexican Wolf requested Brookfield Zoo to establish a new breeding pair as well as to participate in ongoing reproduction studies.

The zoo’s current alpha pair, Zana and Flint, are being moved to a facility in Eureka, Missouri, where they will continue to be important to the population through science. Springer, a female yearling also will be sent to the facility in Eureka.

Six males—Rio, Azul, Mateo, Jeff, David, and Temp—are being sent to an accredited zoo in Springfield, Missouri.
In addition, two young female Mexican wolves will be arriving at Brookfield Zoo before the end of 2018. They will be participating in a reproductive hormone monitoring study during the upcoming breeding season and placed in new permanent homes in fall 2019.

The Chicago Zoological Society has been a partner in the multi-agency Mexican Wolf Recovery Program, led by USFWS since 2003. It has contributed to the program by collaborating on two cross-fosterings of pups born at Brookfield Zoo; the release of one of its adult females to the wild, who subsequently had a litter of pups; and taking part in population-wide fertility studies evaluating methods to improve pregnancy rates.

Mexican wolves are the rarest subspecies of gray wolves in North America. Approximately 4,000 wolves once lived in their historical range, which included central and northern Mexico and the southwestern United States. In 1976, the USFWS added the species to the Endangered Species List. As of August 2017, the population of the species in professional care is 281 individuals in 55 institutions. There are currently a minimum of 113 Mexican wolves living in the wild in the U.S. and approximately 31 in Mexico.