Alaska, often called the Last Frontier, is defined by expansive territory and diverse ecosystems, spanning from the frigid Arctic to the temperate rainforests of the Southeast. This vastness supports a spectacular range of iconic and ecologically complex wildlife. Understanding Alaska’s animal life requires appreciating the full spectrum of its terrestrial and marine inhabitants.
The Official State Mammal
The official state land mammal of Alaska is the moose, a designation formally adopted in 1998. This enormous herbivore is the largest member of the deer family globally; the Alaskan subspecies, Alces alces gigas, is the biggest of all. Large adult males can weigh between 1,200 and 1,600 pounds and stand over six feet tall at the shoulder.
Moose are widespread, inhabiting boreal forests and mixed deciduous woodlands across most of the state, from the Southeast panhandle to the Arctic Slope. They are particularly abundant along major river corridors and in areas recently shaped by wildfires, where young, dense stands of willow and birch provide abundant forage. Their diet consists primarily of woody twigs in winter, transitioning to aquatic vegetation and forbs during the summer months.
Iconic Terrestrial Giants
Several other large land mammals define the Alaskan interior and northern plains, most notably its three distinct bear species. The Brown Bear, often called the Grizzly Bear inland, is an omnivore whose diet varies significantly based on location and season. Coastal brown bears, such as those found on Kodiak Island, grow to immense sizes by gorging on protein-rich salmon during the annual spawning runs.
Interior grizzly bears rely more heavily on vegetation, consuming roots, berries, and grasses. Meat makes up only a small fraction of their year-round diet in some areas. The smaller Black Bear is found mostly in forested regions throughout the state but is generally absent from the treeless northern and western coasts. The Polar Bear inhabits the far northern coastline and sea ice, relying almost entirely on seals for sustenance.
The barren-ground Caribou, a subspecies of reindeer, dominates the northern landscape, undertaking some of the longest terrestrial migrations on Earth. Massive herds, such as the Porcupine Caribou Herd, travel thousands of miles between their winter ranges and their calving grounds on the Arctic coastal plain. The caribou is profoundly tied to the cultural identity of Alaska Native communities, including the Iñupiaq and Gwich’in peoples, who have relied on the animals for food, clothing, and tools for millennia.
Essential Marine and Coastal Life
Alaska’s immense coastline and rich waters support a vibrant oceanic ecosystem, home to a massive population of marine mammals and fisheries. The Bowhead Whale, which can live for over 100 years, holds the distinction of being the state’s official marine mammal. Other cetaceans, including the Humpback Whale and the resident Killer Whale (Orca), are common sights in the waters of the Gulf of Alaska and Prince William Sound.
Pinnipeds like the Steller Sea Lion and various seal species, including Harbor Seals and Ribbon Seals, populate the rocky shores and ice floes. The Steller Sea Lion, the largest of the eared seals, forms large rookeries on the outer coasts. Northern Fur Seals migrate from the Pacific Ocean to the Pribilof Islands for breeding.
Coastal life is defined by the abundance of five species of Pacific Salmon. These anadromous fish are a foundational species, transferring vast amounts of marine nutrients into the terrestrial ecosystem as they return to their natal streams to spawn. The five species are:
- Chinook (King)
- Sockeye (Red)
- Coho (Silver)
- Pink (Humpy)
- Chum (Keta)
The King Salmon is the largest, often exceeding 50 pounds, and is designated as the state fish. This environment also supports large populations of avian life, including the Bald Eagle, which congregates along salmon rivers, and the Horned and Tufted Puffins, which nest in dense colonies on remote coastal cliffs.