extreme north. They are animals that know no boundaries. From Russia
to Alaska, from Canada(mostly) to Greenland and on over to Norway's
Svalbard archipelago. Polar bears are well-adapted to severe cold.
Winter temperatures in the far north often plunge to -40F or -50F and
can stay that way for days or even weeks.
A thick layer of blubber (up to 4.5 inches thick) provides polar bears
with such excellent insulation that their body temperature and metabolic
rate remain the same even at -34F. A polar bear's body temperature is
98.6, which is average for mammals.
On bitterly cold days with fierce winds, polar bears dig out a shelter
in a snow bank and curl up in a tight ball to wait out the storm.
When curled up in a ball, polar bears sometimes cover their muzzles
which radiate heat with one of their thickly furred paws.
Polar bears know how to pack in the fat: A single bear can consume 100
pounds of blubber at one sitting.
The polar bear's compact ears and small tail also help prevent heat
loss. Polar bears have two layers of fur for further protection from
the cold.
Polar bears have more problems with overheating than they do with cold.
Even in very cold weather, they quickly overheat when they try to run.
HOME NEXT
