Ten polar bears were seen swimming in open water off the northern coast of Alaska, an unusual occurrence which was very rare before 2004. It appears that while losing their habitat, bears are forced to swim much more than before, which consumes more energy.

The concern is that bears, particularly pregnant ones, will exhaust themselves on long open-water swims, but for now no adverse effects have been observed following their behavioral change. It is known that some bears are so exhausted after long swims that they fail to move for as long as a couple of days when reaching shore. The polar bears were spotted by a federal marine contractor, Science Applications International Corp., which was looking for whales.

Polar bears were added to the list of animals protected by the Endangered Species Act in mid-May by the U.S. Fish and Wildlife Service. Still the measure might not be enough to save the fate of the big mammal. Scientific reports say that the main reason for the decreasing number of the arctic predators is the reduction of the ice surface, which the bear uses in order to hunt its favorite pray, seals, and not anthropic factors.

Alaska is the only place in the United States where the Ursus maritimus lives. If the planet continues warming, two-thirds of the polar bear population could be gone by 2050, environmental groups allege. The groups are also concerned of oil drilling plans in polar bears' habitat which appear to go forward unrestricted.

The polar bear or Ursus maritimus is a bear native to the Arctic which weighs usually 660–1320 lb when adult. The name maritimus comes from the fact that the polar bear is regarded as a marine mammal due to its intimate relationship with the sea, even if it lives on ice and land.