Latin Name: Ursus Maritimus
Facts About Polar Bears
Polar bears are among the largest carnivores in the world, rivaled only by the Kodiak brown bears of southern Alaska. As its scientific name, Ursus maritimus, suggests, the polar bear is primarily a marine bear.
Numerous adaptations uniquely suit polar bears to life in icy habitats. Their fur is thicker than any other bears’ and covers even their feet, for warmth and traction on ice. A thick layer of blubber beneath their fur provides buoyancy and insulation. Their skin underneath is actually black to absorb heat from the sun.
The long neck and narrow skull of the polar bear probably aid in streamlining the animal in the water, and the front feet are large, flat and oarlike. The polar bear is an excellent swimmer and individuals have been seen in open Arctic waters as far as 200 mi (320 km) from land.
Polar bears are only found in the Arctic region and are highly dependant on the pack ice there since they spend much of their time hundreds of miles from land. The most important habitats for polar bears are the edges of pack ice, where currents and wind interact with the ice, forming a continually melting and refreezing matrix of ice patches. These are the areas of greatest seal abundance and accessibility.
Individual polar bears can travel thousands of miles per year following the seasonal advance and retreat of sea ice. Polar bears are distributed throughout the Arctic region in 19 subpopulations. Alaska, Canada, Russia, Greenland and Norway have polar bear populations.
Staples: Polar bears feed almost exclusively on ringed seals and, to a lesser extent, bearded seals.
Polar bears travel great distances in search of prey. They are also known to eat walrus, beluga whale and bowhead whale carcasses, birds, vegetation and kelp.
The World Conservation Union (IUCN) estimates that there are between 20,000-25,000 polar bears in the world.
Threats to Polar Bears
The most serious threat to polar bears today is climate change. As temperatures in the Arctic continue to get warmer, the sea ice that polar bears rely on for survival melts earlier each spring and forms later each fall. In 2008, the U.S. Fish and Wildlife Service listed the polar bear in Alaska as threatened, the first listing under the Endangered Species Act chalked up primarily to climate change.
Oil and gas development also poses a major risk to polar bears, particularly the threat of oil spills. There is still no proven method of cleaning up oil in broken sea-ice conditions, and an oil spill would not only directly harm polar bears, but would also deplete their prey and contaminate their habitat.