Largest Land Carnivores: Polar bears are the largest land carnivores, with adult males weighing between 900 to 1,600 pounds (410 to 730 kilograms) and measuring up to 10 feet (3 meters) in length.
Excellent Swimmers: Polar bears are powerful swimmers and can swim long distances in search of food. They are known to swim hundreds of miles without rest and can reach speeds of up to 6 miles per hour (9.6 kilometers per hour) in the water.
Black Skin, Not White Fur: Despite their appearance, polar bear fur is not actually white. Each hair shaft is transparent and hollow, reflecting light to appear white. Beneath their fur, polar bears have black skin, which helps absorb and retain heat from the sun.
No Natural Predators: Adult polar bears have no natural predators and are at the top of the Arctic food chain. However, they face threats from humans, climate change, and loss of sea ice habitat.
Hibernation During Pregnancy: Female polar bears enter a unique reproductive strategy called delayed implantation. After mating, the fertilized egg remains dormant for several months before implanting in the uterus.
Dependence on Sea Ice: Polar bears rely on sea ice as a platform for hunting seals, their primary prey. They use their keen sense of smell to locate breathing holes in the ice, where seals come up for air.
Conservation Status: Polar bears are listed as vulnerable by the International Union for Conservation of Nature (IUCN) due to climate change and habitat loss. The loss of Arctic sea ice threatens their survival, as it limits their ability to hunt and travel.