Killer whales are no strangers to Canadian waters. In fact,
orcas are living in every ocean on earth.
The highest densities of killer whales are in the northeast Atlantic
around the Norwegian coast, in the north Pacific along the Aleutian Islands,
the Gulf of Alaska and in the Southern Ocean off much of the coast of
Antarctica. They are also common in the eastern Pacific along the coasts of
British Columbia, Washington and Oregon, in the North Atlantic Ocean around
Iceland and the Faroe Islands. It isn't unheard of to spot some in Baffin Bay.
At this time of year, however, it is unusual for them to be gathered
near Inukjuak, Quebec in Hudson Bay.
They often visit arctic water in more temperate weather, but rarely come
near an ice pack. Recently a group of up
to 18 of them were trapped under the ice in this location. Their presence in this spot is what is
cryptic.
While there is rapid
Arctic sea ice decline in the Hudson Strait, it is still unlikely that killer
whales would come into the bay in the winter.
Average December and January temperature onshore is -15C, with an average
low nearly -30C. The latest ice charts
for the area show not only normal ice present, but significantly lower
temperatures just east of the Hudson Straight, and the whales would have had to
have passed through there to get to their current location. While ice coverage
is still below normal historically, there is about twice as much ice there this
year as there was just two years ago.
Occasionally, killer whales swim into freshwater rivers. Beluga whales, native to the area, winter in
the open waters of the Hudson Straight and in the spring return to the larger
rivers nearby for calving. Belugas are
typically gone from the Bay itself by the time the ice gets just a couple of
inches thick. The freshwater river that
flows into the bay at this area is full of rapids, and not nearly deep enough
to house killer whales, even for a short time.
As the ice builds along the shore and into the river, the tide action
pushes it up creating a very ragged terrain of solid ice. For most of the winter, this ice is very
thick which would make it difficult for the air-breathing orcas to surface. In the past few days, the wind and tides have
been slowly closing the pickup truck sized hole the whales were using for
breathing.
Winds shifted overnight, however, and today the whales
appear to have escaped to open water.
Will they come back?
http://www.museevirtuel-virtualmuseum.ca/sgc-cms/expositions-exhibitions/nunavik/e-nunavik-0202.html
Inujjuamiut Foraging Strategies: Evolutionary Ecology of
Arctic Hunting Economy By Eric Alden Smith
http://www.deanheron.com/killerwhale.htm
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