Perhumid rainforests of Sitka spruce and western hemlock predominate. Water-tolerant plants, such as sphagnum moss, sedges, bog kalmia, and shore pine, occur in peatlands. Alpine tundra heath meadows and barrens occur at higher elevations. Bald eagles and marbled murrelets nest in forested areas on the islands and coastal mainland in this Section. Vancouver Canada geese nest and winter throughout southeast Alaska.
Blue grouse are common throughout the area.
Northern water shrews, deer mice, and long-tailed voles are commonly present. Marten were introduced to Baranof Island in 1934 and to Chichagof Island from 1949 through 1952. Red squirrels were introduced to these islands in 1930. Mountain goats occur on the mainland and were introduced to Baranof Island in 1923. Sitka black-tailed deer occur throughout the Section.