Following on from THIS ARTICLE, a search on Google for fires in Hudson Bay and Cambridge Bay in the Canadian Arctic, brought up NO results.
However, I did find this article which
talks (in 2012) of high temperatures in the 50-60F, compared with
near 90 degree temperatures stretched all the way to the frozen
shores of Cambridge Bay in extreme northern Canada.
If I have my geography right this is on the eastern edges of the Beaufort Sea, where we have recently (March) seen ice breaking up
If I have my geography right this is on the eastern edges of the Beaufort Sea, where we have recently (March) seen ice breaking up
This
isn't newsworthy?!!
I suspect we are not supposed to know about this.
I suspect we are not supposed to know about this.
Rare
wildfires threaten Canadian polar bear habitat
Wildfires
sparked by lightning near Canada's Hudson Bay are threatening the
habitat of polar bears, encroaching on the old tree roots and frozen
soil where females make their dens, a conservation expert on the big,
white bears said on Thursday.
16
August, 2012
Polar
bears are more typically threatened by the melting of sea ice, which
they use as platforms for hunting seals, their main prey. But those
who live near Hudson Bay spend their summers resting up on shore when
the bay thaws, living in dens dug in the frozen soil among the roots
of stunted spruce trees.
Fires
in this area are rare, said Steven Amstrup, a former polar bear
specialist with the U.S. Geological Survey and now chief scientist at
the nonprofit conservation organization, Polar Bears International.
"It's
a cool, wet environment that doesn't burn very often," Amstrup
said by telephone from Washington state. "It's not an
environment where the forest is adapted to fires very much."
Unusually
hot, dry weather in Manitoba, Canada, and lightning strikes caused
several fires through Wapusk National Park across known polar bear
dens in July, said Manitoba Conservation Officer Daryll Hedman.
High
temperatures this week in Churchill, Manitoba, were in the upper 50s
to mid-60s F (15 to 18 C), with overnight lows above freezing.
The U.S. National Snow and Ice Data Center indicated in a map of
Arctic ice cover released this week that the vast majority of Hudson
Bay is ice-free.
Female
polar bears in the western Hudson Bay population use dens under the
root crowns of small, slow-growing spruce trees that grow in
permafrost soils along the banks of rivers and lakes. Some dens have
been used for over 100 years.
"Not
only is the permafrost no longer permanent, tree roots needed to
stabilize the den structure are disappearing," Amstrup said.
"The kinds of habitats where mother polar bears in this area
give birth to their cubs are simply disappearing as the world warms."
CUBS
VERY VULNERABLE
Historically,
the soil in most areas around Hudson Bay is frozen solid below a
surface layer about one foot thick that thaws and re-freezes
seasonally, Amstrup said.
In
recent years, that top layer of soil has gotten increasingly thicker,
so the thawing goes deep enough to defrost the soil around the tree
roots, making the openings that the bears dig collapse, Amstrup said.
When
the trees burn, as some may this summer, their roots die out and
further damage the polar bear dens, he said.
Unlike
other polar bear populations, where pregnant females use dens dug in
snow, Hudson Bay females come ashore to these tree-root dens to rest
and give birth, remaining in the dens until the following spring.
"They're
essentially food-deprived in the summertime. They come ashore and
basically just rest and try to save energy. They crawl into these
dens, it's cool in there, they're not harassed by insects and they
basically just rest until the snow comes and until they give birth,"
Amstrup said.
Without
these earthen dens, he said, females would not be able to conserve
their energy as well. And if snow does not come early enough, cubs
could be born out in the open, where they would be exceedingly
vulnerable.
"Cubs
are born at about a pound and a half (680 grams), blind, nearly
hairless, essentially immobile and totally helpless," he said in
a follow-up email. "Their survival depends upon the shelter of
the den to protect them from the elements."
Polar
bears have government protection in Canada and the United States. The
U.S. polar bear population in Alaska is listed as threatened under
the Endangered Species Act because of increasing damage to their icy
habitat by climate change.
Position of the Beaufort Sea
Breakup of ice in the Beaufort Sea - http://robinwestenra.blogspot.co.nz/2013/03/the-polar-ice.html
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