|
Beary Christmas! Polar Bears Bring Holiday Cheer
By Bunny Stamler
The urban invasion has begun. They are showing up on our lawns, in our Christmas trees, and on our holiday cards. Scientists call them ursus maritimus - the bear of the sea. We know them as the bear of the snow, the famous polar bear.
How appropriate then that the big white bear has become increasingly associated with winter and the holidays. Like snowmen, the popular snow bear resides in the frozen north. While we place lighted bears in our yards for decoration, Santa has real polar bears on his lawn at the North Pole.
I have observed polar bears up close, although not on the frozen tundra. I took a behind-the-scenes tour of the polar bear habitat at Sea World in Orlando, Florida - probably the most popular place for Texans to view live polar bears. The Wild Artic exhibit contains nearly 900,000 gallons of man-made seawater at a cool fifty degrees, creating a virtual Arctic Ocean that is home to the polar bears, as well as walruses, beluga whales, and harbor seals.
I learned some amazing things about polar bears. In a word, they are awesome. They are the largest land carnivore on the planet. Adult males can be more than nine feet long and weigh up to 1,430 pounds. They are excellent, long-distance swimmers, often seen miles out at sea in the Artic Ocean, swimming from one ice floe to another in their hunt for seals.
The most unusual fact about polar bears is that they aren't really white. I learned this when I got to handle a polar bear pelt, otherwise I wouldn't have believed this myself. Their skin, like their nose and foot pads, is solid black. Their fur isn't even white - it is clear and colorless, like nylon fish line.
The coarse transparent hairs have a hollow inner core that scatters ultra-violet light by some unknown mechanism, converting 95% of the sun's rays into heat when it reaches the bear's black skin. It is the reflection of the sun that causes the transparent fur to appear white. So not only does a polar bear's fur camouflage him in the snow, it creates heat and is water-proofed - a perfect insulated coat for the harsh Artic environment.
Here is another fact everyone should know about polar bears: they are found only in the northern hemisphere, not in Antarctica. Even though we see polar bear cartoons and decorations alongside with penguins, in the wild the two never meet. Penguins belong to the southern hemisphere. At opposite poles, polar bears and penguins are truly a world apart.
At this time of year, a mother polar bear is in her maternity den, which she clawed into a snowdrift, where she has given birth to twin cubs. She will nurse them until March or April. Then the little family will leave the den and make its way to the sea ice where the mother will spend most of the year feeding, protecting, and teaching her cubs. They will return to the den the following winter. After two years with their mother, the young cubs are old enough to fend for themselves.
There are about 22,000 polar bears in the wild, 60% in Canada. Being on top of their food chain makes polar bears a good indicator of the overall health of the artic environment.
There are some alarming signs that the Artic and the polar bears are headed for trouble. Warmer than normal temperatures are causing the disappearance of sea ice from which polar bears hunt their prey. When the edge of the ice retreats to the north during summer, bears must follow the ice floes to hunt or become stranded on land, living off of stored fat, until the sea ice forms again in the fall. A longer warmer summer means less time on the ice to hunt for food, resulting in starving polar bears and no cubs.
Fortunately Canada, the United States, Denmark, Norway, and Russia have signed an International Agreement on the Conservation of Polar Bears and their Habitat. Even though this agreement can do little about climate change, it does restrict the hunting of polar bears and directs each nation to protect their habitats.
Coupled with conservation efforts from such organizations as the World Wildlife Fund, hopefully we'll have the popular snow bears around for many more holidays and generations to come.
|
