Arctic Alaska settlement in Arctic Alaska was driven first by discoveries of gold and later on by the extraction of petroleum. The ecosystem consists largely of tundra covering mountain ranges and coastal plains which are home to bears, wolves, sheep, oxen, reindeer, and numerous species of birds, the north coast has been defined as the Arctic coastal tundra ecoregion. Arctic Alaska is also the location of the Arctic National Wildlife Refuge, Gates of the Arctic National Park and Preserve, and the National Petroleum Reserve-Alaska. The Arctic experiences midnight sun in the summer and polar night in the winter. Arctic Alaska Arctic Alaska
White-tailed ptarmigan season, while willow catkins, mountain avens flowers, and chickweed blooms, other flowers and leaves, lichens and berries form the majority of the ptarmigan's diet in the summer. Once fall and winter arrive in the region, the ptarmigan feeds on pine needles, seeds, willow and alder buds and twigs. Winter food sources have a much higher cellulose content than does summer forage, so the ptarmigan relies on bacteria-aided digestion in the cecum to extract essential nutrients. During the summer, the ptarmigan eats grit to assist in digesting plant material. White-tailed ptarmigan males are usually monogamous and remain with the same mate