Snowy Owl
The Snowy Owl, Bubo scandiacus, (Polar Owl, White Owl, Snow Owl, Great White Owl, Ookpik, and Arctic Owl) is the heaviest of all North American owls, weighing in at 2.5-2.9 kg (3-6 lbs). Bubo, from the Latin, simply means “large owl;” scandiacus is a Latinized word referring to Scandinavia because this is where the bird was first discovered. As their name suggests, Snowy Owls are a northern-dwelling species, nesting worldwide on the treeless tundra above the Arctic Circle. During a typical winter, some remain close to their breeding areas while others head south into southern Canada and the northern United States. A similar situation exists in Europe and Asia. Snowy Owls are found over much of Greenland
Commonly, some Snowy Owls migrate south each winter; in one recent year, they were spotted in 31 U.S. states. But every 3-5 years hundreds to thousands of owls move southward to Canada and the U.S. These exceptionally large movements are called “irruptions.” It was once thought that these were hungry owls flying south in search of food. An abundance of food, like lemmings, on their breeding grounds produces a profusion of young owls who then look for new areas to inhabit.
Snowy Owls usually seek open habitats like their native arctic tundra. Typical habitats include coastal beaches and harbors, open grasslands and agricultural fields, wetlands, and frozen bodies of water. They are often found in suburban or urban settings, roosting on just about anything, including the ground, fences, telephone poles, rocky walls, tree snags, and other structures.
From these perches, Snowy Owls seek nearly anything that moves. Their diet varies, though many pursue voles, mice, shrews, and other small lemming-like rodents for food. Ducks and other waterbirds are surprisingly common prey sources, while rabbits, weasels, muskrats, pigeons, and other birds are also taken. Hunting is done with a watch-and-wait technique. Snowy Owls perch in a regular location and use their acute vision and highly sensitive hearing to locate prey; they can even hear prey moving under the snow. Snowy Owl ears are asymmetrically positioned on their heads to assist with pinpointing the source of the sounds. Unlike many other owl species, Snowy Owls are diurnal - active during the day. This makes sense for a bird that nests in the perpetual daylight of an Arctic summer. However, during the winter, the birds tend to be most active at crepuscular periods, or around dawn and dusk.