borealforest.org

 
BACK

Mammal Species of the World's Boreal Forests

BIRDS

   
Ovis canadensis
Bighorn Sheep

Description

Distinguishing Features - A full-grown bighorn may average 101 cm at the shoulder and range from 79 - 158 kg in weight. The Bighorn's body is compact and muscular; the muzzle, narrow and pointed; the ears, short and pointed; the tail, very short. The cloven hooves are sharp-edged, elastic, and concave, double-lobed, with foreprints slightly larger than hindprints - somewhat similar to deer prints but less splayed. The fur is deerlike and usually a shade of brown with whitish rump patches; it is smooth and composed of an outer coat of brittle guard hairs and short, gray, crimped fleece underfur. The summer coat is a rich, glossy brown but becomes quite faded by late winter.

Bighorn Sheep The male sheep is called a ram and can be recognized by his massive brown horns. The horns curl back over the ears, downs and up past the cheeks. By the time a ram reaches 7 or 8 years of age, he can have a set of horns with a full curl and a spread of up to 84 cm. Ewes, the females, are smaller than the rams and have shorter, smaller horns that never exceed half a curl.

Habitat

The natural range of the Bighorn Sheep was formerly in the Rocky Mountains from southern Canada to Colorado, but is now reduced to small bands protected by inaccessible habitat or by refuges. A desert subspecies, Ovis canadensis nelsoni, ranges from Nevada and California to west Texas and south into Mexico. Another rare member inhabits the Sierra Nevada Mountain of California. Bighorn inhabits alpine meadows, grassy mountain slopes and foothill country near rugged, rocky cliffs and bluffs, allowing for quick escape . In winter, Bighorn prefer slopes 2,500 - 5,000 feet where annual snowfall is less than 150 inches a year, because they cannot paw through deep snow to feed. Their summer range is between 6,000 - 8,500 feet in elevation.

Diet

Bighorns are primarily grazers; their typical diet consists of mainly grasses, sedges and forbs.

Notes

Bighorns are noted for the head-to-head combat between males; combat has sometimes been observed to last for longer than 24 hours. Males do not defend territories but rather engage in these battles over mating access to a particular female. Age as well as horn determines male dominance status. Although not as well built for climbing as Mountain Goats Oreamnos americanus, Bighorn Sheep zigzag up and down cliff faces with amazing ease. They use ledges only a few inches wide for footholds, and bounce from ledge to ledge over spans as wide as 6 - 8 metres. They can move over level ground at 50 kilometres per hour and scramble up mountain slopes at 25 kph. They also swim freely, despite their massive bulk and weight of their horns.

Human activities are responsible for the Bighorn's decline. Grazing, mining, depletion of water holes, homesteading and use as camp meat spelled disaster for the Bighorn. In the desert, off-road vehicles, trespassing cattle, poaching in the 1960s and early '70s, drought, disease and Mountain Lion predation have worked together to push this population towards the edge of extinction in some locations.



Return to Top of Page



Home | Forest Capital of Canada | About Our Website |
Ontario's North (West) Forest | Boreal Forests of the World | North (West) Forest Industry |
World Links and Resources | "Forest Finder" Search Engine | Educational Resources |
What's Happening | Contacts | Site Map |