Snowy Owl
Snowy Owl
Bubo scandiacus
At a Glance
A large, powerful owl of the high Arctic tundra, colored for camouflage during northern winters. In summer it may be nomadic, concentrating and nesting where there are high populations of the small rodents called lemmings. At other times it takes a wide variety of prey, including birds as big as geese. During some winters, large numbers of Snowy Owls appear south of the Canadian border; those that stop in towns and cities invariably cause a stir and attract media attention.
All bird guide text and rangemaps adapted from by Kenn Kaufman漏 1996, used by permission of Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Category
Owls
IUCN Status
Vulnerable
Habitat
Fields, Meadows, and Grasslands, Landfills and Dumps, Saltwater Wetlands, Shrublands, Savannas, and Thickets, Tundra and Boreal Habitats
Region
Alaska and The North, California, Eastern Canada, Great Lakes, Mid Atlantic, New England, Northwest, Plains, Rocky Mountains, Southeast, Southwest, Western Canada
Behavior
Direct Flight, Flap/Glide, Undulating
Population
29.000
Range & Identification
Migration & Range Maps
Migration not well understood. Nomadic in breeding season, concentrating where prey abundant. Numbers moving south in winter quite variable from year to year, probably relating to populations of prey in the north.
Description
24" (61 cm). W. 4' 7 (1.4 m). Bulky and round-headed, with yellow eyes. Variable black barring: young females heavily marked, old males almost pure white. White owls seen in other climates are usually Barn Owls or downy young of other owl species.
Size
About the size of a Heron, About the size of a Mallard or Herring Gull
Color
Black, Brown, Gray, White, Yellow
Wing Shape
Narrow, Pointed
Tail Shape
Rounded, Short, Square-tipped
Songs and Calls
Usually silent; hoarse croak and shrill whistle on breeding grounds.
Call Pattern
Flat
Call Type
Hoot, Rattle
Habitat
Prairies, fields, marshes, beaches, dunes; in summer, arctic tundra. Breeds on tundra, from just north of treeline to the northernmost land. Prefers very open tundra, either in hilly country or wetter areas near coast. Winters in open country, including prairies, farmland, coastal marshes, beaches, large airports.
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Behavior
Eggs
3-11. Clutch size quite variable, with more eggs laid in years when prey is abundant. Eggs whitish, becoming nest-stained. Incubation is by female only, 31-33 days; male brings food to incubating female. Eggs hatch at intervals, so that female will be caring for first young while still incubating last eggs.
Young
Female remains with young; male brings food, female takes it and feeds them. Young may leave nest after 2-3 weeks, but not able to fly well until about 7 weeks; fed by parents up to at least 9-10 weeks.
Feeding Behavior
Often hunts by day. Usually hunts by watching for prey from a perch, then pursuing it in swift flight and catching prey in talons. Sometimes seeks prey by flying low, or by hovering and watching ground. May locate prey by sight or sound.
Diet
Varied, includes lemmings, plus other mammals and birds. In Arctic, may feed almost exclusively on lemmings when these are available. Otherwise, feeds on wide variety of prey. Takes mammals including rabbits, hares, voles, ground squirrels. In coastal areas may feed heavily on birds, including ducks, geese, grebes, murrelets, and sometimes songbirds. Also may eat fish, carrion.
Nesting
In many regions of Arctic, may breed mainly in years when lemmings are abundant, failing to nest at all when lemmings are scarce. Male owl defends territory with deep hooting in early spring. In courtship, male flies with deep, slow wingbeats, often carrying a lemming in his bill; landing near female, he leans forward, partly raising wings. Nest: Chooses a raised site, on top of mound or ridge in hilly country, or on hummock in low-lying areas, always with good visibility in very open tundra. Site may be used for several years. Nest (built by female) is simple depression in tundra, with no lining added.
Climate Vulnerability
Conservation Status
Formerly many were shot during southward invasions in winter. Most North American breeding areas are remote from effects of human disturbance, but climate change is likely to affect many Arctic birds. Has declined in parts of breeding range in northern Europe.
Climate Threats Facing the Snowy Owl
Choose a temperature scenario below to see which threats will affect this species as warming increases. The same climate change-driven threats that put birds at risk will affect other wildlife and people, too.