The Arctic char (Salvelinus alpinus) is present in North America in both saltwater and freshwater form. It is found throughout the polar regions and is the most northerly distributed of the char species. In Alaska, they are known only in the freshwater form. Arctic char are found in lakes in the Brooks Range, the Kigluaik Mountains, the Kuskokwim Mountains, the Alaska Peninsula, Kenai Peninsula, Kodiak Island, and in a small area of Interior Alaska near Denali Park.
Like all chars, Arctic char have light colored spots on a dark background. They are variable in color depending on environmental conditions and time of year. The back is dark with a brownish or olive cast. The sides are lighter, fading to a pale belly. The overall color may be brown, yellow, gold, orange, or red. As the char approaches spawning, the spots, belly, and fins take on a bright orange, red, or gold cast, and the lower fins have brilliant white leading edges. The entire body may become golden or orange. Spawning colors are less brilliant in males than in females. Depending on the region, this species can be from 2 to 10 pounds in weight.
After reaching sexual maturity at an age of 6 to 9 years, Arctic char are thought to spawn every other year. Spawning usually occurs from August through October at sufficient depth to be protected from winter ice. In some lakes, pre-spawning char congregate near inlet streams or waterways connecting lakes, but they move back into the lake to spawn. Growth and maximum size may vary greatly, depending on the productivity of the particular lake and the presence of other fish species.