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by Bob Tuck
Urban residents are sometimes startled by the sight of a large, dark bird silently gliding across a moon-lite residential street. How, they may wonder, does such a large bird find a place to live among houses, schools, businesses, and other human structures?
Photo credit: Bob Tuck
The great horned owl (Bubo virginianus) is one of the largest owls in North America, and one of the widest distributed bird species in the world. From the treeline in northern Alaska and Canada, coast to coast south to Central America, and then further south throughout South America down to Tierra del Fuego. Other members of the genus Bubo are found worldwide, except for Australia and islands in the Southwest Pacific.
These large raptors stand almost 2 feet tall and have a wingspan of nearly four feet. They are more common in urban areas than many people realize. Any park or open area with large conifers where they can roost out of sight during the day may well harbor a pair. I have heard the familiar, deep voice in urban Vancouver, WA, for example.
The key to this wide distribution is their versatility. Great horned owls do not build their own nests. Instead, they use what is available in their area. In rural areas, they commonly nest in the abandoned nests of other large raptors, such as red-tailed hawks, or crows and ravens. They also nest on cliff ledges, the broken tops of large trees, or large tree cavities. In urban areas, they nest in old crow nest, ledges on large buildings, in lofts or attics, or any place that provides seclusion and protection for their 2-4 eggs.
These large predators also make use of a wide variety of prey, which also contributes to their use of many habitats. They can take large prey, such as skunks, jackrabbits, pheasants, opossums, or other medium-sized birds and mammals. They also can make use of smaller prey such as mice, rats, gophers, squirrels, bats, snakes, frogs, fish, and large insects. In urban areas, their prey is largely mice and rats, frogs, large insects, and birds such as sparrows, starlings, and pigeons. Given the large numbers of rodents and several species of birds in urban areas, it is not hard to understand how great horned owls may find such areas inviting places to call home.
Even if you don’t hear or see them, you may find their large pellets on the ground beneath their roost or other prominent perch. Like other raptors, owls swallow their prey whole or in large pieces—bones, hair, teeth and all. Within 24 hours, these indigestible parts are formed into oblong-shaped pellets with the fur and hair on the outside and bones and teeth in the center, and then “cast,” or regurgitated. Pellets provide a record of the prey consumed by the owls and are an invaluable source of information for wildlife biologists.
Even though you may live in an urban area, many species of interesting wildlife call your neighborhood home. These large owls are one of the most interesting.
Great Horned Owl Books and Resources