Classification and Range
The snowy owl was recently reclassified in the genus Bubo, which is part of the family Strigidae or "typical" owls. This circumpolar owl inhabits tundra regions of Eurasia and North America. During the fall and winter, it migrates to southern Canada and northerly parts of the United States. During years when high numbers of owl young are produced, the snowy owl may wander as far south as the central United States.
The snowy owl prefers open areas for its breeding range, including tundra and grasslands. During winter it seeks open areas to the south, including prairies, marshes or shorelines.
The snowy owl is the heaviest North American owl, and one of the largest in overall size. They average 20-27 inches (51-69 cm) tall, with a wingspan of almost 5 feet (1.5 m). They have large, round heads, black beaks, no visible ear-tufts and yellow eyes. As with most owls, females are larger than males; females average 5 pounds (2.3 kg), males 4 pounds (1.8 kg). The female's body is white and highlighted with dark brown bars and spots. Males are nearly pure white. Both sexes of immature owls are heavily marked with brown barring.
Up to 25 years in captivity. Birds have been documented to live at least 10 years in the wild.
In the wild: Snowy owls prey primarily on lemmings, mice and voles. They also eat large birds, such as ptarmigans and a variety of waterfowl. Snowy owls have been known to wade into water to catch marine animals with their talons.
At the zoo: Mice, rats and coturnix quail.
Courtship begins in May, with males performing aerial displays of dives, soars and exaggerated wing beats. They often carry a dead animal in their beaks as food gifts for prospective mates. While on the ground, males may also spread their wings to impress females. Once paired, the owls nest on a prominent point that offers a good view in all directions. Nests are not elaborate, simply being a scooped-out area lined with feathers and moss. The amount of available food determines clutch size. An average of seven eggs are usually laid, but clutch size may be even larger if prey is exceptionally plentiful. During periods of few prey, owls may not nest. Females incubate their eggs for 32-34 days. The female incubates and broods, while the male hunts for food.
About three to four weeks after hatching, young leave the nest and scatter in close proximity of the nest. Once all the chicks have left the nest, both parents must feed the scattered young. Young fledge seven to eight weeks after hatching. Due to nearly 24 hours of light per day in the tundra, snowy owls are active any hour of day or night, and perch on the ground or any raised object while searching for food. They may gather in groups of up to 20 or more owls when they disperse south in the fall, particularly when they find a location with plenty of prey.
Snowy owls are very protective parents. A male will dive and strike at most any intruder that enters its territory or threatens its family. This includes animals such as arctic foxes, wolves and even humans. Another means of defense against predators is to act as if it's wounded. If a predator comes too close to the nest, either parent may drag their wing(s) on the ground. They hope to trick the predator into thinking that the wounded owl is an easy meal, while they slowly lead it farther and farther away from the nest.
Location at the Zoo
Woodland Park Zoo's snowy owls can be seen in our Northern Trail exhibit area. Other owls can be viewed in our Raptor Center and near Bug World.
During the breeding and nesting season, snowy owls inhabit tundra areas that experience severe weather conditions. Well adapted to live in these harsh environments, snowy owls face few threats and their populations are stable. This changes, however, as these owls migrate south and come into contact with human civilization. Although not a threat to the species snowy owls die from flying into utility lines, wire fences, automobiles, airplanes (at airports) and other human structures. Some owls are even killed by hunters.
Many raptor species are in trouble. Human-caused changes in land use are escalating, and this affects the habitats and migratory corridors required by some raptors for survival. Vast forests are being removed for timber and other paper products, and industrial emissions are polluting water and air resources. Critical shoreline and riparian zone habitats are being rapidly converted by expanding human communities and agricultural needs. Shooting and trapping are also lowering raptor numbers. It's only a matter of time until more raptor species may face extinction, unless we take measures to protect their habitats.
Humans need raptors. Here are only a few of the benefits raptors provide:
- Raptors help keep animal populations in balance.
- Raptors consume many animals that humans consider as pests, including mice, rats and destructive species of insects. This helps to control disease and damage to crops.
- As top predators of their food chain, raptors are an indicator species of the overall health of the ecosystem in which they live.
- Of equal importance, witnessing wild raptors enriches each of our lives. Imagine what life would be like if we could no longer hear the haunting evening call of the owl.
How You Can Help!
Efforts to save threatened and endangered raptors require cooperation and support at international, national, regional and individual levels. You can help in this cause. Join and become active in Woodland Park Zoo and other conservation organizations of your choice. Eliminate or reduce pesticide use. Support breeding programs for endangered birds of prey at zoos and other animal care organizations.
Contact Woodland Park Zoo at firstname.lastname@example.org to find ways you can support conservation programs at the zoo. Discover more about raptors by calling the Peregrine Fund (208) 362-3716. Learn other ways you can help conserve wildlife and their habitats by visiting our How You Can Help page.
Sources and Suggested Reading
Burton, J.A. (editor). 1992 (third ed.). Owls of the World: Their Evolution, Structure and Ecology. E.P. Dutton, New York, NY. 216 p.
Jarvis, Kila and Denver W. Holt. 1996. Owls: Whoo Are They? Mountain Press Publishing Company, Missoula, MT. 59 p.
Zoobooks. 1992. Owls. Wildlife Education, Ltd., San Diego, CA. 17 p.