Polar bears have long been a Canadian icon. They live in colder northern climates and hunt for seals. But the climate is changing and the earth is warming. As a result, polar bear numbers are in decline. As the sea ice recedes, the bears lose places to hunt and are stuck ashore, often starving. And their birth rates are declining. Some scientists believe their very survival may be at risk. Now scientists are in northern Manitoba to study the polar bear and its bleak future.