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Quiz
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The
Parks / Manitoba
/ Wapusk
National Park
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Animal behaviourist Jane Waterman is an annual
visitor to Cape Churchill, compiling research
on the play behaviour of the young males along
the coast awaiting freeze-up. This display of
sparring and wrestling is the premier attraction
for serious wildlife photographers and tourists
to the Churchill area. Viewing is done from
the safety of Tundra Buggies - large buses
mounted on crop-duster tires - placing the
spectators well above the frozen arena. Waterman
has collected extensive data on the relative
dominance of different bears, which may be indicative
of their mating success. But she has also noted
some interesting behaviour in their play. Rubbing,
rolling and sliding on the snow may be an effort
to cool hot spots on their body as revealed
by infrared cameras.
A widely held belief that
the hair of polar bears is hollow, allowing
light to penetrate to their black skin and transmit
heat to their bodies has not been supported
by Waterman's research. So far, she reports,
the hair shaft does not appear to transmit light.
There
are roughly 10,000 Beluga Whales living in Hudson
Bay. About 3,500 are considered part of the
Churchill population. They move into the river
estuaries shortly after the ice breaks up, probably
looking for warmer environments for their newborn
calves. A baby beluga is dark brown at birth,
gradually lightening to a bluish grey. The white
coloration of adult whales occurs around six
years of age. The whales here grow to between
3 and 4 m in length with an average weight around
400 kg, somewhat smaller than the belugas found
in more northerly waters. They have up to 40
fully developed teeth and feed on capelin, crab,
shrimp and Arctic char. The fact that they are
minus a dorsal fin is possibly an adaptation
to their northern environment, facilitating
their movement under ice. They also differ from
most cetaceans in their spinal structure. The
seven upper vertebrae are not fused, giving
them an articulated neck.
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