Wednesday, February 16, 2011

Climate Change and Arctic Residents

Grizzly Bear

14 FEB 2011: REPORT

Arctic Roamers: The Move of Southern Species into Far North

Grizzly bears mating with polar bears. Red foxes out-competing Arctic foxes. Exotic diseases making their way into once-isolated polar realms. These are just some of the worrisome phenomena now occurring as Arctic temperatures soar and the Arctic Ocean, a once-impermeable barrier, melts.

by ed struzik

Scientist John England was flying in the High Arctic last summer when he spotted something large moving on a tiny island in the Beaufort Sea, not far from the Alaska-Yukon border. When he and the helicopter pilot moved in to get a closer look, they were astounded to see a grizzly bear prowling the shoreline.

What this brown bear was doing in the kingdom of its white cousin is not entirely clear. But a week later when I joined England in the field, we found the tracks of the animal leading to a partially excavated den. It was obvious that the bear had no intention of going back to the mainland.

Up until about twenty years ago, sightings of grizzlies in the High Arctic were extremely rare; a quirk of nature, many biologists thought, that may
The new concern is that interbreeding might result in hybrid creatures that will water down a unique gene pool.
have simply occurred because the bear ended up walking the wrong way or because it had strayed too far following mainland caribou that sometimes cross the sea ice to the Arctic islands. But that thinking began to change in recent years as more brown bears and a succession of other animals such as red fox, white-tailed deer, Pacific salmon, and killer whales began showing up in areas traditionally occupied by polar bears, Arctic fox, caribou, Arctic char, and beluga whales.


No comments: