Alaska has diverse ecosystems supporting varied animal life. From rainforests to tundra, these environments offer unique habitats for countless species. Its vast, undisturbed wilderness serves as a refuge for many animals.
Land Mammals
Alaska is home to an impressive collection of large land mammals, many of which are iconic symbols of its wilderness.
Brown bears, also known as grizzlies in interior regions, inhabit diverse ecosystems across the state, including forests, sub-alpine mountains, and coastal areas. These omnivores adapt their diets seasonally, consuming salmon, berries, grasses, and even preying on moose and caribou calves. Coastal brown bears, like those found on the Kodiak Archipelago, can be larger due to abundant salmon and berries; mature males sometimes weigh up to 1,700 pounds.
Black bears, the most abundant bear species in Alaska, are smaller than brown bears and found throughout most forested areas. Their fur color varies widely, from black to brown, cinnamon, or a rare blue-gray “glacier bear” phase in some southeastern regions. These adaptable omnivores forage on sedges, grasses, insects, and berries, with salmon becoming an important food source in coastal areas during summer. They move to lower elevations in spring and summer for food and seek sheltered areas for hibernation as winter approaches.
Polar bears, specialized marine mammals, inhabit the Arctic and adjacent areas, relying on sea ice for hunting seals. Their range includes Alaska’s Arctic waters and terrestrial habitats along the northern coast. While most polar bears remain with the receding pack ice in summer, some come ashore along the Beaufort Sea coast to rest until shore-fast ice reforms. Females give birth to one to three cubs in snow dens, often located on coastal or river banks.
Moose, the largest members of the deer family, are found across much of Alaska, from the Southeast Panhandle to the Arctic Slope. They are abundant in areas with dense willow, aspen, and birch shrubs, often found along major rivers or in recently burned regions. These herbivores browse on twigs, leaves, and aquatic plants. Adult male moose, or bulls, can weigh between 1,200 and 1,600 pounds and are recognized by their massive antlers, spanning up to six feet wide.
Caribou, known for extensive migrations, roam Alaska’s treeless tundra, mountains, and northern forests. Alaska is home to 32 caribou herds, totaling approximately 900,000 wild caribou. Both male and female caribou grow antlers, unique among deer species. Their diet shifts seasonally from leaves of willows, sedges, and flowering plants in summer to lichens and dried sedges in winter, accessed by digging through snow with shovel-shaped hooves.
Wolves, found throughout mainland Alaska and many of its islands, are adaptable predators inhabiting diverse environments from rainforests to arctic tundra. They live in packs averaging six or seven animals, often maintaining territories ranging from 300 to 1,000 square miles. Wolves prey on moose and caribou, supplementing their diet with Dall sheep, small mammals, and occasionally birds or fish. Their fur color varies from black to nearly white, with gray or black being most common.
Dall sheep, recognized by their striking white coats and the males’ massive curling horns, inhabit Alaska’s rugged mountain ranges. They prefer dry alpine areas with steep slopes and cliffs, which provide escape terrain from predators like wolves and brown bears. These herbivores feed on grasses, sedges, lichens, and mosses, with their diet diversifying in summer when food is abundant. Dall sheep often visit mineral licks, sometimes traveling many miles to consume soil at these formations.