Polar bears are found throughout
the circumpolar Arctic on pack ice, along or near coasts, and on
islands. They share this habitat with indigenous peoples, and animals
such as ringed seals, arctic foxes, narwhal, beluga whales, and
millions of migratory birds. There are believed to be at least 22,000
polar bears worldwide, and about 60 per cent of these are in Canada.
Tracks have been reported as far north as the pole, but scientists
believe few bears travel beyond 82° north latitude. The northern
Arctic Ocean has little food for them.
Polar bears spend much of their time at or near the edge of the pack
ice. This is where they are most likely to find food. As the southern
edge of the arctic ice cap melts in summer, some bears will follow the
retreating ice north to stay close to seals and other prey. Other bears
spend their summers on land, living off body fat stored from successful
hunting in the spring and winter. When the ice returns in the fall, the
bears leave land to resume life on the sea ice.
Increasing levels of greenhouse gases in the atmosphere are causing
temperatures around the globe to rise. As a result, sea ice in the
Arctic is melting earlier and forming later each year. Polar bears are
left with less time to hunt for food. As their ice habitat shrinks bears
in the southern limits of the Arctic--especially around Hudson Bay,
Canada--face a grave threat to their survival. At the current rate
of climate warming, experts predict that there will be no ice in Hudson
Bay by the year 2080.
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Map of polar bear distribution. (click to enlarge)
The world's southern-most polar bears live
year-round in James Bay, Canada. The species range extends as far south
as the winter maximum sea ice extent and includes adjacent land
masses.
Polar bears on pancake ice in the marginal ice
zone a few kilometers from the ice edge.
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