The Arizona-Sonora Desert Museum is part of a multi-state, binational breeding program involving bighorn sheep.

One of the program's goals is to raise the number of captive-bred sheep kept in different facilities, and to increase their genetic diversity by moving them between the other participating entities.

"Six like-minded institutions got together and decided that it was about time that we started looking at sustainable breeding of bighorn sheep...over a year and a half ago Utah's Hogle Zoo, (Los Angeles Zoo), the Living Desert...San Diego and Phoenix, and ourselves all got together and came up with a plan," said Shawnee Riplog-Peterson, curator of mammalogy and ornithology at the Arizona-Sonora Desert Museum. "And as of today, we have 46 animals in prime breeding condition for this."

The goal is to have six lambs by the end of the season, she added.

The sustainable species program is part of the Zoological Association of America's efforts to not take animals from the wild, "but create a genetic diverse breeding program within the United States, and we have also included two zoos from Mexico as well," said Rosemary Prawdzik, director of marketing and sales at the Arizona-Sonoran Desert Museum.