• A female grizzly bear with a freshly-caught salmon in British Columbia's Great Bear Rainforest. (Photo: Bianca Boudreau/Can Geo Photo Club)

It's Bear Week here at Canadian Geographic, and to kick things off, we thought we'd share some interesting facts about these deceptively cuddly-looking mammals, illustrated with amazing photos by our Photo Club members.

Polar bear (Ursus maritimus)
Inuit poetry refers to the polar bear as Pihoqahiak, "the ever-wandering one." Polar bears spend many months of the year at sea hunting seals, their main dietary staple, and can swim and run long distances.

A polar bear swims in open water off the coast of Baffin Island. (Photo: Todd Mintz/Can Geo Photo Club)

Despite all appearances, polar bears are not actually white. Their skin is black and covered with dense underfur, which is protected by an outer coat of hollow, translucent guard hairs. It was once thought that the guard hairs acted as fibre-optic cables, conducting light to the bear's black skin, where it could be absorbed to maintain body heat, but this theory was disproved in 1998. In fact, polar bears become overheated at temperatures above 10C, and when kept in warm, moist conditions, particularly in captivity, their outer hairs may actually turn green as a result of algae growing inside the hollow tubes.

A polar bear appears to be impatiently waiting for sea ice to thicken in Churchill, Man. (Photo: Catherine Page/Can Geo Photo Club)

Black bear (Ursus americanus)
The American black bear is the world's most common bear species and the most widely-distributed bear species in North America. Black bears primarily live in forests, although they are frequently attracted to human communities thanks to the ready availability of food. They possess short, sharp, curved claws that assist with climbing trees, which they do to escape predators, find food, and sleep.

A black bear rests in a tree in Port Moody, B.C. (Photo: Darren Quarin/Can Geo Photo Club)

Black bears have a large vocabulary and use a variety of hums, grunts, and other vocalizations to communicate with each other.

A black bear on the prowl in Finch, Ont. (Photo: Shelley Jacques/Can Geo Photo Club)

Depending on food availability, black bears will occupy a range of anywhere from five square kilometres to more than 10,000 square kilometres. The bears mark their territory by rubbing their bodies against trees and clawing at the bark.

A black bear marks its territory by rubbing its back against a tree in Manning Provincial Park, B.C. (Photo: Claude Robidoux/Can Geo Photo Club)

Kermode bear (Ursus americanus kermodei)
The Kermode bear, or “Spirit Bear,” is actually a subspecies of the American black bear primarily found in the Central and North Coast regions of British Columbia. Contrary to popular belief, Kermode bears are not albinos, nor are they related to polar bears. Their whitish-cream colouring is caused by a double recessive gene unique to the subspecies.

A Kermode or "Spirit Bear" in Sandspit, B.C. (Photo: Laura Sample/Can Geo Photo Club)

Studies have found white bears are 30 per cent more effective at catching salmon during the day than their black counterparts because their lack of colouring makes them less visible to the fish.

This Kermode bear still has traces of lunch around its mouth as it crosses a stream in the Great Bear Rainforest. (Photo: Kyle Blaney/Can Geo Photo Club)

Grizzly bear (Ursus arctos horribilis)
The grizzly bear is actually not a distinct bear species, but rather a North American subspecies of the brown bear. Its Latin name, Ursus horribilis, means "terrifying bear" and is a reference to its character; grizzlies are more likely to attack than flee when threatened. Mothers defending their cubs are responsible for 70 per cent of human deaths due to grizzly attacks.

A male grizzly stands out against a field of spring snow. (Photo: Neal Weisenberg/Can Geo Photo Club)

Grizzlies were once found from Alaska to Mexico and as far east as the western shores of Hudson Bay, but hunting and habitat loss have gradually pushed them north and west. Today, approximately 20,000 bears live in Canada — most in British Columbia, which has made substantial efforts to protect them.

A female grizzly is pursued by a male during mating season in the Khutzeymateen Grizzly Bear Sanctuary. (Photo: William Bickle/Can Geo Photo Club)

The largest grizzly ever recorded weighed about 1,200 pounds and was 10 feet high when standing.

A female grizzly stands on her hind legs to see above the tall grass in the Khutzeymateen Grizzly Bear Sanctuary. (Photo: Jenny Stevens/Can Geo Photo Club)

Grizzlies have a social hierarchy, with adult males at the top, and teenage bears at the bottom.

A pair of recently weaned female grizzlies lounge on the remains of a logging jetty in Knight Inlet, B.C. (Photo: Steve Williamson/Can Geo Photo Club)

Have a bear photo, fact or story to share? Tweet it to us using the hashtag #BearWeek!