Ovis canadensis canadensis
Carnero salvaje (Sp), Dickhornschaf (G), Mouflon du Canada (F).
DESCRIPTION (male) Shoulder height 40-44 inches (102-112 cm). Weight 200-250 pounds (90-113 kg), occasionally as much as 300 pounds (135 kg). Females are considerably smaller, seldom exceeding 175 pounds (79 kg).
The Rocky Mountain bighorn is the largest sheep in North America and one of the largest in the world. It is a heavy-bodied animal with massive horns and a full, coarse, grayish-brown coat. The muzzle is white, as are the backs of the front legs and insides of hind legs. The belly is white in the groin area, with the white color sometimes extending forward onto the chest. The rump patch is large and white, surrounding the dark tail. The horns are very thick at the base and tend to carry the thickness throughout their length. Typically, the horns curl close to the head and are broomed off at the eyes where further growth would interfere with vision. Females have short, thin horns.
HABITAT Mountain ridges and basins, usually above timber line, but often in timbered areas as well. Its diet has more browse and less grass than that of the California bighorn.
DISTRIBUTION Alberta: Western part of the province along the Rocky Mountains near the border with British Columbia. British Columbia: The Omineca-Peace and Kootenay wildlife regions in the Rocky Mountains near the border with Alberta. Also introduced in two areas (Unit 3-17, west of Spences Bridge, and Unit 3-20, southeast of Kamloops) in the Thompson-Nicola Wildlife Region that were formerly California bighorn habitat.
Arizona Southeastern part of the state near the border with New Mexico. Colorado: Throughout the Rocky Mountain region. Idaho: Western and central parts north of Interstate 84. Montana: Western parts. Nevada: East-central part near Mt. Moriah and the northeastern part. New Mexico: Southwestern part near the Arizona border, and in the Pecos Wilderness in the north-central region. Oregon: Northeastern corner. North Dakota: Southwestern part of the state. South Dakota: (non-indigenous) Three areas in the southwestern part, where they were introduced from Wyoming and Colorado. This was once the range of the extinct Audubon bighorn. Utah: One herd in the northeastern part on the Nevada border, another northeast of Green River. Washington: Extreme southeastern parts. Wyoming: Mainly in the northwest, but also in the north-central and south-central parts. Nebraska: Northwestern part of the state.
Many populations are the result of introductions and/or transplants, but we treat all as indigenous for record-keeping purposes.
REMARKS It has been said that of all the world's sheep, the Rocky Mountain bighorn-especially one with horns of trophy proportions-is by far the most difficult to collect. Surveys indicate that bighorn hunts have the lowest success ratios of all sheep hunts. There are compensations, however. To quote the late Jack O'Connor, "..the pursuit of the brown bighorn is the cream of mountain hunting. The old bighorn will lead the hunter into the most beautiful country he's ever seen. He'll wear him out, give him buck fever and break his heart; but if the hunter is the type that's susceptible to sheep fever he'll never be completely happy hunting anything else."
STATUS Although secure, bighorn sheep are nowhere plentiful. They are under constant pressure from loss of habitat, competition from domestic livestock for limited forage, and diseases carried by domestic sheep. There are at least 51 species of parasites known to affect bighorn sheep, 36 of which are carried by domestic sheep and 18 by cattle. Bighorns are particularly vulnerable to pneumonia brought on by lungworm infection, and catastrophic die-offs have sometimes resulted.