Friday, December 19, 2008
What bears do in the cold of winter
When the mercury is cringing in the thermometer as it is during these coldest days of winter here, you might wonder how do the animals survive?
Temperatures in Red Lake are falling to -30 to -40 C. If you don't know Celsius temps just remember that -40 C is the same thing as 40 below Fahrenheit. These are cold temperatures any way you measure them.
Some animals have found ways to avoid the cold. The most obvious is the black bear who puts on a thick layer of fat over the summer and snuggles into a den in October before the winter snows arrive.
You might think they would dig deep below the frostline, like the true hibernator, the woodchuck, does. But surprisingly their dens are almost on the surface. Their favorite places are where a tree has fallen over and left a bit of a cave where its roots have been raised from the ground.
I found one of these occupied dens right near our home in Nolalu a few years back. You can see from the photos how unimpressive the den was. There's actually a bear in this den. The root ball that it crawled under measured about two feet high and was created when a small balsam fir, perhaps 8 inches in diameter, was tipped over by the wind.
The bear dug under this spot to enlarge the space so it could just squeeze into it. It then curled up and turned its back toward the hole.
Bears don't really hibernate. They just sleep and you can wake them up as I and my dog, Bud, did in this instance.
Bud, a Black Lab, would always growl when he smelled a bear and he started growling here. I knew he must smell a bear den but I couldn't see where it would be. Finally Bud would go no further ahead and I looked right at my feet and saw the little opening with black hair sticking out of it. About this point the bear started growling inside the den and we beat a hasty retreat.
Bears give birth in the den in a marsupial-like manner. The tiny, hairless cub or cubs as there are often two, must find its way from the womb to the teat, then spend the rest of the winter surrounded by its mother's warm fur. It's similar to how a kangaroo gives birth except there's no pouch.