Polar bears are present in Alaska, classified as a native species. Alaska is the only U.S. state that hosts three bear species: polar, black, and brown bears.
Alaskan Polar Bear Habitats
Polar bears in Alaska are primarily found along the Arctic Ocean coastline, in the northern and western regions. Their habitat extends across the Chukchi Sea and Beaufort Sea, home to two distinct populations shared with Canada and Russia.
The primary habitat for polar bears is sea ice, used for hunting, breeding, and travel. In winter, bears can be found as far south as St. Lawrence Island. During summer, as sea ice recedes, many bears remain with the pack ice. Some come ashore along the Beaufort Sea coast to rest until shore-fast ice forms.
Coastal areas and barrier islands also serve as important denning habitats. Terrestrial denning habitat includes lands within 32 kilometers (about 20 miles) of the northern coast, particularly between the Canadian border and the Kavik River.
Life in the Alaskan Arctic
Polar bears possess specialized adaptations to thrive in the frigid Alaskan Arctic. Their thick fur, consisting of dense underfur and longer guard hairs, provides insulation and repels water. Beneath their white or yellowish coat, their skin is black, which helps absorb and retain heat. A thick layer of blubber, up to 10 centimeters (4 inches) thick, further insulates them.
Their large, flat paws function like snowshoes, distributing weight to prevent sinking in snow, and are effective paddles for swimming. Polar bears are considered marine mammals due to their reliance on marine ecosystems and ability to swim for extended periods. Their keen sense of smell, acute eyesight, and excellent hearing aid them in locating prey.
The diet of polar bears primarily consists of seals, particularly ringed and bearded seals, which they hunt from the sea ice. They often wait patiently at seal breathing holes or stalk seals resting on the ice. When hunting is successful, they prioritize consuming the energy-rich blubber of seals to build up fat reserves, vital for surviving periods of food scarcity. While seals are their main food source, polar bears are opportunistic hunters. They also consume walruses, beluga whales, and scavenge on whale carcasses or terrestrial foods like bird eggs when marine prey is less available.
Pregnant females typically create snow dens in October and November, giving birth to cubs, usually twins, in December or January. These dens, found on land, barrier islands, or sea ice, provide protection for the cubs until they emerge in late March or early April.
Conservation and Future Outlook
Polar bear populations in Alaska face considerable challenges, primarily due to rapid changes in the Arctic environment. The U.S. Fish and Wildlife Service has listed polar bears as a threatened species under the Endangered Species Act, largely because of sea ice habitat loss. The Arctic is warming two to four times faster than the global average, leading to significant sea ice decline.
This loss directly impacts their ability to hunt seals, resulting in shorter hunting seasons and longer periods on land. Consequently, bears may experience reduced body fat, lower reproduction rates, and increased cub mortality. For example, the Southern Beaufort Sea population has seen a substantial decline, estimated at around 819 bears from previous numbers.
Beyond climate change, human activities like oil and gas exploration and development pose additional threats. These activities can disturb denning areas, fragment habitats, and increase the risk of oil spills, which could be devastating to bears. Seismic testing, for instance, involves noisy blasts that can disrupt bear movements and potentially impact undetected dens.
Conservation efforts in Alaska involve a multi-pronged approach, including biological monitoring, deterrence programs near human settlements, and managing food attractants. The U.S. Fish and Wildlife Service manages polar bears in cooperation with the Alaska Nanuuq Commission and the North Slope Borough. International agreements with Canada and Russia also facilitate management and research for shared polar bear populations. Protecting habitats, minimizing climate change effects, and reducing human-polar bear conflicts are central to these conservation strategies.