Snowy Owl

 

Common Name: Snowy Owl

Class:  Aves

Order: Strigiformes

Family: Strigidae

Genus: Bubo

Species: Bubo scandiacus


Photo: Ivan Andrijevic

 

 

 

Snowy Owls are in the Order Strigiformes and the Family Strigidae which groups them together with "true owls". They are monochromatic which means that males and females look alike. They are large (23 inches, 58 cm), nocturnal predatory birds. Snowy Owls are white all over with some dark barring and spots, a large round head and yellow eyes. Immature Snowy Owls have bold black barring.

 
Photo: Ivan Andrijevic

The breeding range of Snowy Owls extends from northern Alaska throughout the Canadian Arctic Islands. Their wintering range extends south from the breeding range to southern Canada and northern United States. They can be found in patches throughout central California and the Gulf states. Snowy Owls live in areas of open tundra which are near tree lines to the edge of polar seas. They prefer open farmlands, marshes and meadows. Their nests have been spotted near sea level to mountain slopes. Snowy Owls eat mostly mammals, ranging from small rodents to large hares. They will also eat passerine nestlings and meduim-sized geese. Some times they will eat fish and other aquatic animals, but that is less common. Snowy Owls forage by swooping. This means they snatch food from the ground in their talons after they have glided downwards from a perch with their wings spread.

Snowy Owls hunt prey at night and because of this have adapted hearing that allows them to better sense their prey. A ruff of feathers is located just outside the ears which acts as a reflector to channels sounds into the ears. Once a sound is heard, the owl can pinpoint a location with 1.5 degrees in both the horizontal and vertical planes. Owls also have the ability to be silent hunters because of the structural modification of the first primary feather on each wing. The edge of the feather is serrated, instead of being smooth, which disrupts the flow of air over the wing in flight. This disrupts the vortex heard when air flows over a smooth surface thus, making them silent flyers. During courtship displays, the male performs a jerky, undulating courtship flight that ends in a near vertical landing. When they are on the ground, the male will stiffly dance with his wings spread while holding a dead rodent. Snowy Owls have a monogamous mating system and have one brood per year. The female will build a nest on a hummock, especially on a bare-topped gravel bank. It is usually minimally lined. Many times geese and eiders will nest near the Snowy Owls for protection against the Arctic Fox. The female will lay 3-4 white eggs and will be responsible incubating the eggs for the 32-34 day period. The young hatch asynchronously  and the first can be nearly fledge by the time the last nestling is hatched. Young are semialtricial which means they are downy, blind, immobile and fed by their parents. Both sexes tend to young until they are ready to fledge which occurs 16 days after hatching. Many times, the females will stay together until the fall.

Snowy Owls are a nomadic species constantly moving and because of this they are not always seen in WNY. However, if they are seen it is usually during the winter in open areas where they prefer to hunt.

 

Birds of Western New York is brought to you by the Institute for the Study of Human-Animal Relations at Canisius College in Buffalo, NY.