Caribou in Canada Across the country, caribou are struggling to survive in their ever-changing habitat. Facing
a modern world, they are losing the battle.
Click on a caribou for more details on each subspecies.
Caribou subspecies: Caribou commonalities
For the Kids:
Check out CG Kids Animal of the Month for our fact sheet on Caribou (Rangifer tarandus).
Caribou are the only members of the
deer family where both males and females have antlers. The antlers grow tall and flat, branching
out forward — male antlers are larger. Calves have small spiky
antlers that grow into a full rack as they mature, while older caribou’s
antlers become sparser as they age. When antlers first develop they
are covered in velvet — a fine, thin layer of skin filled
with nerves and blood vessels that stimulate growth. At maximum
growth, the velvet dries and falls off, leaving the branch-like
antlers bright white. Antlers regenerate yearly; males tend to lose
theirs after the mating season, while females retain theirs until
spring.
Like antlers, hooves also alter with the changing seasons. The
large, wide, curved hooves keep caribou from sinking in snow and
function like paddles when swimming. In winter, the hard exterior
of the hooves grow around the edges; the inner soft pad shrinks
and is covered in hair to keep from freezing. This adaptation
gives the caribou better traction to outrun predators and helps
them dig through snow and ice to find food. In summer, these hard
edges are worn away from walking across rocks and rough terrain;
the inner soft pad grows to prevent caribou from sinking in swampy
areas. Caribou also use their hooves as a defense mechanism. Small
scent glands are located on the back of the legs, where the ankle
meets the hoof. When caribou sense danger, they rise on their
hind legs and release a scent to warn the rest of the herd.
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Caribou fur also adapts to the extreme weather conditions. Although
colouration varies among the subspecies, the shade of their fur
changes with summer and winter. The thick coat is made up of long
hollow hair that insulates in the winter and provides the caribou
with buoyancy for swimming in summer.
Caribou are relatively quiet animals. Within the herd, they communicate
through snorting and grunting. On cold days, a clicking noise
is audible as caribou walk — from the motion of bones and
tendons around the hooves. Another distinct sound is the clattering
of antlers as bulls fight each other around mating season.
The largest threats to caribou are wolves, grizzly bears and
golden eagles. Caribou are fast and can outrun their predators — wolves
and bears attack sick or old caribou that are slower in the herd.
Golden eagles are largely a threat to newborns. Flies don’t
pose a huge threat to caribou, but they are cause for great annoyance.
Warble flies lay eggs on the caribou’s skin and the larvae
emerges and burrows into the caribou’s back, eating skin
and fat. Nosebot flies causes breathing difficulties for caribou
as they hatch in the caribou’s throat and lungs. To avoid
the swarm of flies, caribou try to run away, or stay close to
others.
10,000 caribou from the George River herd died in 1984 crossing the Caniapiscau River in Quebec during their fall migration. A nearby power dam was blamed for causing flooding in the river.
