We
can breathe easy for now about lemming populations in the Canadian
Arctic, the Nunatsiaq News assures us. But this "mighty keystone species"
as the newspaper dubbed them recently, could be compromised elsewhere
in the world, if winters shorten and get wetter as climate change
plays out.
The more snow the better for this palm-sized
rodent, the newspaper reported from the ArcticNet conference in
Ottowa, which took place in December 2010.
"I'm not really concerned about the lemming
population in North America," said Frederic Bilodeau, a PhD candidate
at the Université Laval who presented his Bylot Island research
at the conference. "This is definitely going to be a problem in
time. Of course, the entire ecosystem will be in trouble if the
lemming numbers go down. But we're not seeing that right away."
They need snow, the Nunatsiaq News said
in a January story, because they burrow under it for nine months
of the year. They build tunnels in it, and it needs to be thick
enough to shelter them from predators and give them space to have
their young as well as have access to food, which is vegetationnot
to mention keep warm.
So far there's enough snow in the Canadian
Arctic, Bilodeau said. But before you breathe a sigh of relief,
though, look to Scandinavia, where the furry critters are succumbing
to an influx of predators, or Russia, where voles are competing
with them for food.
According to the Smithsonian Museum's
Arctic Studies Center in Washington, D.C., lemming numbers rise
and fall with the food supply, which is plants and berries. The
Scandinavian lemming will migrate in a huge group when the food
runs out, the Smithsonian said, "through meadows, woods and towns,"
and will swim across a large body of water if they run across one.
One thing they won't do, however, is take
a flying leap. Debunking a popular misconception, the museum says,
"The stories about lemmings jumping off cliffs are a myth."
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