Polar Bears live across Northern Russia, Alaska, Canada, Greenland and Norway, numbering around 22,000 bears. They depend on sea-ice to hunt and breed. As sea ice recedes further and further from the coastline, Polar Bears are forced to swim farther in order to reach vital food sources, leaving them exhausted and vulnerable. The following video
from Ignatius G. Rigor at the University of Washington demonstrates the extent of ice loss in the Arctic.
From album: Polar Bears in Svalbard and Melting Sea Ice