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Wapusk is the Cree name for the White Bear,
which has come to symbolize this area. Polar
bears are the largest terrestrial carnivore,
weighing an average 1000 lbs. Despite their
size, they can travel at speeds up to 30 m/hr.
They can pick up a scent 32 km away and detect
a seal buried under 3 feet of snow and ice.
They have no natural enemies and no fear.
Mating occurs out on the ice
during the spring. As the ice melts, the bears
are forced on shore. The warm water currents
from the Churchill River cause ice dams to form
southward along the coast in the fall; consequently,
it is here that the bears return each summer
to await the winter freeze. During the autumn
months, pregnant females make their dens, digging
a hole in the face of an esker, which will be
sheltered by snow once winter comes. Cubs are
born in March and stay with the mother for two
years. Should the cubs survive, the female will
not be available to mate again for 2-3 years.
It is rare to see males and
females together on land. Males will attack
unprotected cubs in order to make the females
available to breed. The population at Churchill,
numbering some 1200 bears, seems to have staked
out territories for mothers with cubs, mature
males and immature males - the teenagers
who engage in fascinating play fights to the
delight of spectators.
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While the bears are out on
the sea ice, their primary job is to build their
fat reserves, feeding almost exclusively on
ringed seal. Polar bears begin to congregate
here in July as their feeding grounds out on
the bay disappear. They spend four months on
land, essentially without food, until the ice
forms again around the end of October. A pregnant
female will go into a den for close to nine
months and when she emerges with her cubs, still
be able to trek between 60 and 100 kilometres
back to the coast. During their time on land,
the bears lose an enormous amount of weight,
but surprisingly not muscle mass, since they
live off their stored fat. One tagged female
weighing in at a mere 115 kilograms after the
birth of her cub in the spring, when recaptured
the following year, had bulked up to 400 kilograms.
Dr. Malcolm Ramsey of the
University of Saskatchewan has been pioneering
research into the metabolic processes of these
bears with the hope that humans can learn something
from these ’classic yo-yo dieters’.
Through the course of his research, Ramsey has
tagged and catalogued more than 4000 bears (as
of 1996), making the Churchill polar bears the
best censused population in the world.
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