Return to the Wild - Evolving perspectives on Canadian wildlife
Bighorn sheep can be found in the Canadian Rockies, interior British Columbia and in the U.S.

Did you know?

The bighorn sheep can lose 20 to 25 percent of its body weight over the winter and gain it back again the following season.

Scientific name: Ovis canadensis
Average weight: 110 kg–130 kg (male)
53 kg–91 kg (female)
Average lifespan: 8-12 years (male)
10-15 years (female)
A bighorn sheep stands with a backdrop of blue Alberta sky.

About

Biology

As the name suggests, the bighorn sheep is best known for its big horns. The male, or ram, has the larger set, which spirals backward, while the female, or ewe, has shorter, spiked horns. The ram’s horns are highly valued by hunters.

One of the bighorn’s assets is its hoofs, which have a hard outer rim and a soft concave middle. The hoofs enable the sheep to maintain its grip on steep, rocky slopes, stand on ledges only five centimetres wide and jump up to five metres from one ledge to another.

The bighorn is much larger and more muscular than its relative, the domesticated sheep. It has a short brown coat, a white eye patch and white on the back of its legs and rump. Being non-domesticated, it lacks wool.

Habitat and behaviour

The bighorn lives in sparse mountain regions, where it grazes on grasses and vegetation. Its climbing skills enable it to escape predators such as wolves, bears and cougars, which find it difficult to negotiate the rugged terrain. And the sheep’s excellent eyesight and high vantage point allow it to notice movement hundreds of metres away.

The mountains are also the stage for monumental clashes between bighorn rams, whose horns are status symbols in the battle for dominance or ewes. The rams rear up on their hind legs, then launch themselves at each other in charges at up to 32 kilometres per hour. The fights can last for hours, and the head-on collisions can often be heard up to two kilometres away. Although death can sometimes result, the rams’ thick, bony skulls usually protect them.

Despite these epic encounters, the bighorn is quite sociable and can live in bands numbering anywhere from 10 to 100 sheep. Ewes and rams intermix only during mating season, in the fall. The ewe gives birth to one lamb, which it keeps on a high ledge for safety. Yet every now and then, a golden eagle or other mountain predator picks an opportune moment to grab a lamb.

Range

In Canada, the bighorn sheep is confined to the Rocky Mountains straddling the Alberta-British Columbia border and to mountain ranges in the British Columbia Interior. It is also found in the United States and northern Mexico.

Its range varies in summer and winter. During its seasonal migration, the bighorn sometimes moves only a few hundred metres up or down the mountainside or it may travel to another mountain range 10 to 20 kilometres away.