Snowy Owl (Bubo scandiacus)

The Snowy Owl (Bubo scandiacus) is a large, white owl with a rounded head and yellow eyes. The plumage ranges from all white (some old males) to white with many dark bars and spots (particularly in females and immatures). This is a bird of the open Arctic tundra of both the New World and Old World. Snowy Owls nest on the ground and feed mainly on lemmings, which they hunt both day and night (other mammals and birds are also eaten, as well as some fish and carrion). In winter, there is some movement south and individuals are seen at least irregularly south to the northern United States (and even, rarely, the Gulf Coast), Iceland, the British Isles, northern continental Europe, central Russia, northern China, and Sakhalin. These wandering winter birds are generally seen in open country such as prairie, marshes, fields, pastures, and sandy beaches. In years when lemming populations crash, many Snowy Owls move south to the northern tier of states in the United States and some go much farther. These wandering birds (usually heavily barred younger birds) often perch on the ground, low stumps, or buildings. In many Arctic regions, Snowy Owls breed mainly in years when lemmings are abundant and fail to nest at all when lemmings are scarce. Although Snowy Owls are silent off the breeding grounds, males defend their breeding territories with deep hooting in early spring. A courting male flies with deep, slow wingbeats, often with a lemming in his bill; reaching the female, he leans forward and partly raises his wings. The nest site is typically a mound or ridge in hilly country or a hummock in low-lying areas. It is always in very open tundra with high visibility. The same site may be used for several years. The nest (which is built by the female) is a simple depression in the tundra with no lining added. Clutch size is highly variable (3 to 11 eggs) and correlated with prey abundance. The eggs are whitish, but become stained in the nest. The female incubates the eggs for 31 to 33 days and the male brings food to the incubating female. Egg hatch is not synchronized, so the female cares for her first young while still incubating her last eggs. The female remains with the young and the male brings her food, which the female feeds them. The young may leave the nest after 2 to 3 weeks, but they are not able to fly until around 7 weeks and are fed by their parents until at least 9 or 10 weeks. Although most North American Snowy Owl breeding areas are far from major human disturbance, this species has declined in parts of its breeding range in northern Europe. (Kaufman 1996; AOU 1998; Dunn and Alderfer 2011)

Rights Holder: Leo Shapiro