Snowy Owl

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Image:Snowyowl.JPG

Common Name: Snowy Owl
Scientific Name: Bubo scandiacus

Size: 20 -27 inches (51-68.5 cm); Wingspan: 54-65 inches (137-164 cm)

Habitat: Arctic Circle; Circumpolar regions of the old and new worlds. Found on the Arctic tundra or in open grasslands and fields.

Status: Least Concern. Global population: 300,000. Natural enemies are few - Arctic foxes and wolves prey upon them on their tundra breeding grounds, while skuas and jaegers may take eggs or chicks.

Diet: Mostly lemmings and voles; Some mammal prey include mice, hares, muskrats, marmots, squirrels, rabbits, prairie dogs, rats, moles, and entrapped furbearers. Birds include ptarmigan, ducks, geese, shorebirds, Ring-necked Pheasants, grouse, American coots, grebes, gulls, songbirds, and Short-eared Owls. Snowy Owls will also take fish and carrion.

Most hunting is done in the "sit and wait" style. These Owls are highly diurnal, although they may hunt at night as well. Prey are captured on the ground, in the air, or snatched off the surface of water bodies. When taking snowshoe hares, a Snowy Owl will sink its talons into the back and backflap until the hare is exhausted. The Owl will then break its neck with its beak.

Nesting: Courtship behavior can begin in midwinter through to March and April, well away from breeding areas. Males will fly in undulating, moth-like flight when females are visible. On the ground males will bow, fluff feathers, and strut around with wings spread and dragging on the ground. Males kill and display prey in caches to impress females, often feeding the female. The Snowy Owl nests almost exclusively on the ground, where the female makes a shallow scrape with her talons on top of an elevated rise, mound, or boulder. Abandoned eagle nests and gravel bars are used occasionally. Nests may be lined with scraps of vegetation and Owl feathers. Nest sites must be near good hunting areas, be snow-free, and command a view of surroundings. There is little breeding site-faithfulness between years or mates in some areas, but in other areas, a pair of Owls may nest in the same spot for several years. Territories around nests range from 1.5 to 6.5 square km (0.6 to 2.5 square miles), and overlap with other pairs.

Breeding occurs in May, Clutch and brood sizes are heavily dependent on food supply. Snowy Owls may not nest at all during years of low lemming numbers. Clutch sizes normally range from 5 to 8 white eggs but may be as many as 14 eggs during high lemming years. They are laid at approximately 2 day intervals and average about 57 x 45 mm. The female incubates while the male brings her food and guards the nest. Eggs hatch in 32-34 days at two day intervals, leading to large age differences in nests with large clutch sizes. Young are covered in white down. Young begin to leave the nest after about 25 days, well before they can fly. They are fledged at 50 to 60 days. Both parents feed and tend the young, and are fiercely protective and may attack intruders up to 1 km (0.6 miles) from the nest! Nestling Owls require about 2 lemmings/day and a family of Snowy Owls may eat as many as 1,500 lemmings before the young disperse. Snowy Owls are single brooded and likely do not lay replacement clutches if their first clutch is lost. Almost 100% nesting success can be achieved during good vole years.

Numbers fluctuate wildly, usually in concert with lemming and vole numbers. For Example, Banks Island may have 15,000 to 20,000 Snowy Owls during good lemming years and only 2,000 during low lemming years with densities ranging from 1 Owl per 2.6 square km (1 Owl per square mile) in good lemming years to 1 Owl per 26 square km (1 Owl per 10 square miles) in low lemming years.

Cool Facts: The Snowy Owl was first classified in 1758 by Carolus Linnaeus, the Swedish Swedish naturalist who developed binomial nomenclature to classify and organize plants and animals. The name "scandiacas" is a Latinized word referring to Scandinavia, as the Owl was first observed in the northern parts of Europe. Other common names for the Snowy Owl are Snow Owl, Arctic Owl, Great White Owl, Ghost Owl, Ermine Owl, Tundra Ghost, Ookpik, Scandinavian Nightbird, White Terror of the North, and Highland Tundra Owl.

During hot weather, they can thermo-regulate by panting and spreading their wings.

The Snowy Owl is the official bird of Quebec and Harry Potter’s owl from the J.K. Rowling book series.


Found in Songbird ReMix Owls of the World Volume 1

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