Bighorn sheep are stocky, muscular animals known for their massive curled horns and impressive climbing abilities. They can be found scattered around southern British Columbia, western Alberta, and parts of the Canadian Rockies in Canada.

Fast facts

Common name: Bighorn sheep

Scientific name: Ovis canadensis

Type: Mammal

Diet: Ruminant herbivores

Group name: A herd (or flock or mob)

Average weight: 73 to 113 kilograms

Average height: 35 to 41 Inches (at the shoulder)

COSEWIC Status: Not determined (2002)

Did you know?

The bighorn sheep has three different living subspecies: the Rocky Mountain bighorn sheep (Ovis canadensis canadensis), the Sierra Nevada bighorn sheep (Ovis canadensis sierrae) and the desert bighorn sheep (Ovis canadensis nelsoni). In North America, the bighorn sheep is one of two species of wild sheep with large horns, the second being the Dall sheep (Ovis dalli).

Physical characteristics and behaviours

Bighorn sheep resemble their goat relatives through their short brown fur and white muzzle, rump, and belly. Their wide-set eyes provide them with exceptional eyesight, which, along with their hearing and strong sense of smell, helps them avoid predators. Their split and rough hooves also aid with their balance and grip, allowing them to move easily on rugged mountain terrain.

The large, curled horns commonly associated with these animals are seen on bighorn males, also called rams. These horns can weigh up to 30 pounds, more than all the bones in an adult male’s body combined. Older rams’ horns can grow over three feet long with a one-foot circumference at its base. While female bighorn sheep, commonly known as ewes, also have horns, they are much smaller with only a slight curvature.

Both rams and ewes use their horns as tools for both eating and fighting. Males often fight for dominance or mating rights by rearing up on their back legs and hurling themselves at one another in charges of up to 20 miles an hour. These fights can last several hours, and the clashing of their horns can be heard echoing through the mountains. Despite the severity of these fights, bighorn sheep’s thick and bony skull prevents them from serious injury.

While bighorn sheep are social animals, rams and ewes live separately, with rams living in bachelor groups while ewes live in herds with other females and their offspring. Rams and ewes only come together during fall mating, where rams fight one another for mating opportunities, resulting in only more substantial older rams being able to mate. Lambs are then born in the spring atop high, secluded ledges, away from bighorn predators like wolves, coyotes and mountain lions. Lambs join their mothers in a herd after one week and are occasionally nursed for up to six months.

Diet

Bighorn sheep are ruminant herbivores whose diet mainly consists of grasses, herbaceous plants, and shrubs. They are selective with their feeding and choose the most nutritious forage available, often meaning newer plants, depending on the plant species.

Habitat and distribution

Bighorn sheep live in the western mountainous regions of North America between southern Canada and Mexico. They often live in steep areas of mountains, with ledges sometimes only two inches wide, which offers them protection from predators. Their ideal climate is dry and rugged, with low grass and herbs. They often migrate long distances in the winter to avoid areas with minimal snow.

In Canada, bighorn sheep are primarily found in southern B.C., western Alta., and the Canadian Rockies. In B.C., they are considered vulnerable, with just over 3,000 in the population, whereas in Alta., they are considered secure, with 11,000 inhabiting national parks and provincial lands.