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Polar Bears are found exclusively in the northern Arctic,
and abound in the northern extremes of Norway, such as the
Svalbard Archipelago, where they number over double
the human population. While staying in the settlements on
Svalbard it is not unusual to see a Polar Bear wandering into
town, in search of food, or just generally nosing around the
research stations. If you come here to see the polar bears
you are unlikely to be disappointed. They can also be found
in northern parts of Greenland, Canada and areas of Russia
within the Arctic Circle.
Bear facts
Apart from their colour, Polar Bears have much physical similarity
to their relations, the Brown Bear of North America.
They are large, stocky creatures, with forelimbs shorter than
their rear limbs, resulting in their lumbering walk. They
can also stand up upon their rear legs, but do so rarely.
Polar Bears are renowned as the largest land carnivore, they
are about 18 - 20ft in length and very heavy, females weigh
about 440-660lbs, males about twice as much.
Face-to-face with bears
Despite the rumoured possibility that they can eat humans,
they would generally prefer not to, though if provoked they
can be very aggressive, and if starved of other food sources
may raid human stores as an alternative, and could attack
if startled.
If you do come across a hungry Polar Bear, be careful to do
nothing to aggravate it, back away slowly and don't run (it'll
take this as a sign to follow), if you have a rifle - which
you should if you're going out in wilderness alone - you should
fire off warning shots first, and only if you are left with
no other choice for your own protection, should you shoot
the Polar Bear.
Food and hunting
Their preferred diet consists of seal, walrus, fish, sea birds
and reindeer, and in summer, they will also eat berries and
other vegetation. Polar Bears use a method of catching their
prey called 'still hunting', which involves standing and waiting
for a seal to emerge from an ice hole, or on the edge of an
ice floe. This method is low in cost as far as energy expenditure
is concerned, but highly inefficient, they have a low success
rate for catching the seals when they do emerge, and often
are forced to survive on as little as one meal a week.
Survival of the fattest
The Arctic environment in which the Polar Bears live has temperatures
as low as minus fifty degrees centigrade, and spend much of
their time drifting along on ice floes, and hunting in icy,
snowy areas. In order to survive this, the Polar Bear, descended
thousands of years ago from North America's Brown Bear, has
developed a number of impressive adaptations. Their size is
particularly important, as larger objects lose heat more slowly,
so the more a bear eats, the longer he can survive in the
cold. They also have black skin, to absorb the warmth from
the sunlight, and thick, white, water repellent fur, which
traps warm air next to the skin when on dry land, and allows
water to role off it when they have been swimming. Their large
feet are furry, and partially webbed, working equally efficiently
as snow shoes or as flippers. Their most unusual skill, but
one essential to their survival is their amazing sense of
smell - they can smell a dead carcass from many miles away,
and a live seal three or four yards under the ice!
Polar Bears are largely solitary animals, but get together
to mate once a year, usually in the summer. They will generally
produce a small litter of two or three cubs, who are tiny
when born (roughly the size of a rat), as well as blind and
helpless, and are raised in a snow hole, close to their mother,
until they are strong enough. to walk.
Bears under threat
Polar Bears are under a number of environmental threats,
for example, oil spills from tankers have devastating effect
on their health directly, as well as by dramatically diminishing
their already limited food supply. Chemical pollution, especially
organic pollutants such as PCB's, have been found to build
up in the fatty tissues of Polar Bears, gradually reaching
such levels that they cause deformities to the sexual organs
and sterility, threatening the reproductive capabilities of
whole colonies. Another significant threat is global warming,
which is gradually reducing the size of the polar ice caps,
and making the Polar Bears habitat smaller and smaller. It
also causes the ice floes to break up earlier each year, and
making the polar bear's hunting even more difficult, and making
their struggle for survival through the long and difficult
winter months even more challenging.
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