For the Birds: A year for Snowy Owls
Saturday, November 19, 2011
Snowy Owl at Ocean Shores, showing heavily feathered feet Photo by Max Waugh |
By Christine Southwick
If you see a large white owl with a black beak and yellow eyes sitting out in the open where it can see in all directions, be assured that is a Snowy Owl. The smaller males (23 inches long) are the signature white; the larger females (28 inches long), and the juvies are white with varying degrees of dark barring.
Their heavily feathered feet, and dense bodies (they average the heaviest North American owl species) plus their coloring make them highly suited for the cold arctic weather. Snowy Owls prefer to hunt in low light during the day, a great adaption for living where summers have no nights.
Snowy Owl. Boundary Bay, BC 11/13/11. Photo by Nancy J Wagner Photography |
Snowy Owls hunt and nest on the ground. They prefer open terrain year round, whether they are above the tree line in the tundra, or here in Washington . The female makes her nest on a snow-free high mound or boulder, with 360 degree visibility, and in May lays an egg every other day with a clutch size of five to eight eggs (14 eggs in high lemming seasons). The female incubates the eggs while the male hunts for both of them, and guards the nest. The eggs start hatching at 32 days, two days apart, making large size differences between the first and later hatchlings.
Snowy Owls Boundary Bay, BC Nancy J Wagner Photography |
The young leave the nest around 25 days after hatching, but can’t fly for about another month. Both parents are fiercely protective, and may drive arctic foxes and wolves away from their territory while intruders are still a half mile from the nest. And skuas (large arctic seabirds) and jaegers (smaller variety of skua) may take an egg or chick, but habitat loss is the greatest threat to Snowy Owls.
Since Snowy Owls keep the nearby area predator –free, and don’t hunt near their own nests, the Snow Goose will often nest near a Snowy Owl nest to improve the Snowy Goose’s clutch success.
Snowy Owls rely heavily on lemmings and voles, especially for feeding their young; each owl can eat more than 1,500 a year. They will also eat other rodents, including hares, marmots, and squirrels. They will eat birds, and actively hunt ptarmigan, ducks, shorebirds, and gulls, especially during low lemming years.
Snowy Owl Whidbey Island. Photo by Steve Mlodinow |
Lemmings have a crash cycle every five to ten years. And indications are that this year may be a crash year, when Snowy Owls may be seen on coastal areas in B.C., Skagit, Vancouver Island, Grays Harbor. Since most males have prime Arctic territory, it is usually the females and juveniles who are forced to travel South in years of hunger from lack of lemmings. If you go to see a Snowy Owl, take a scope, as they are usually far out on driftwood where they have unobstructed views.
Christine Southwick is on the Board of the Puget Sound Bird Observatory and is their Winter Urban Color-banding Project Manager. She is a National Wildlife Federation Certified Wildlife Habitat Steward, having completed their forty hour class. We're happy that she's sharing her expertise with us about the birds in our backyards.
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