Annual Polar Bear Migration Under Way: How It Works and How Climate Change Could Be Impacting It
Melting sea ice means big changes for the world's 20,000 polar bears.
It's part of their annual migration back to Hudson Bay, where sea ice is reforming after months of summer melt. To get to the ice each autumn, they traverse Churchill, Manitoba—the "polar bear capital of the world."
These animals are the most studied group of polar bears on Earth. The renowned Ian Stirling, now retired from the Canadian Wildlife Service, began his groundbreaking research here 40 years ago.
Because this population comes ashore each year, says Steven Amstrup of Polar Bears International, they're relatively easy to count. "Searching for a white bear on green grass and brown rocks is easier than searching for [it] out on the white sea ice."
Churchill has only about 900 people, but several hotels.
