Polar bears live in the Arctic. As of 2015, there are 20,000 to 25,000 living in 19 sub-groups in Canada, Alaska, Greenland, Russia and Norway. They live on the edges of pack ice, in areas where the currents and winds cause continuous melting and refreezing of ice.
As the pack ice melts and refreezes, cracks and openings appear that allow seals, a staple of the polar bear's diet, to surface for air, making them vulnerable to becoming prey for polar bears. Polar bears often travel thousands of miles in their quest to find food as the seas advance and retreat during the year.