Following the Lemming
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 vegetation—not 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.”