Colorado National Monument - Bighorn Sheep

Desert bighorn sheep are some of 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 are making a tentative comeback in southeast Utah due to a comprehensive reintroduction effort by the National Park Service. With one of the few remaining native herds, Colorado National Monument has been a critical area for restoration efforts.

Desert or Nelson’s bighorn sheep (ovis canadensis nelsoni) are considered by most biologists to be a unique subspecies. Desert bighorns have adapted to hot, dry climates, unlike their Rocky Mountain cousins, and have longer legs, lighter coats and smaller bodies. Bighorn sheep are common in Native American pictographs, an indication of their presence and prominence in indigenous cultures.

Accounts from European explorers in the late 1600s estimate that more than two million desert bighorn once roamed the southwest. By the late 1800s however, bighorn sheep had disappeared or declined in many areas. Extremely vulnerable to diseases from European livestock, herd after herd of wild sheep were decimated by pathogens like scabies (an ear mite) and anthrax (a bacterial disease) introduced by domestic sheep. Bighorns were also killed by early explorers, settlers and trophy hunters.

Increased human activity, competition with domesticated cattle and sheep for food, and development are the biggest threats to the desert bighorn sheep today. For remaining herds to survive, intensive management and conservation measures may be necessary. Present and future protection of undeveloped land and wilderness areas are key to the species’ survival.