The Long-tailed Duck or oldsquaw (Clangula hyemalis) is a diving duck. Its head, neck and back are brown and its cheeks grey. The drake keeps this aspect from late spring to early summer. During winter, its head and neck become white whereas a brown spot covers its cheeks' extremity to its neck superior part. The long feather of its tail distinguishes it from other duck species. The female is duller and displays a short tail, a dark back, and a white stomach.
During summer, the species can be found in lakes and ponds of the tundra as well as on coasts and islands. During other seasons, it can also be seen along the northern Québec coasts and in the Ungava Bay. The long-tailed duck mostly eats molluscs and crustaceans.
Couple formation takes place during winter in the tundra. The female is responsible for the nesting spot. It usually prefers an islet high on vegetation to hide eggs from predators. The female lays 6 to 8 eggs that are sat on for 26 days.