Desert bighorn sheep are among the most intriguing mammals of canyon country. They are wary of human contact and blend so well into the terrain they inhabit that sightings are a special event. Once in danger of becoming extinct, the desert bighorn sheep (Onis Canadensis) have made a comeback in parts of western Colorado. A small population was reintroduced to Colorado National Monument in 1979. While more than 230 sheep have been sighted and monitored across the public lands of the Grand Valley, about 40 bighorn thrive in and around Colorado National Monument (2010).