This large owl is sometimes called the tiger of the air; it is our fiercest, most powerful and aggressive owl. It weighs up to 3.5 pounds, is 20-23 inches in length and has a wingspan of nearly five feet. Females are slightly larger than males. A great horned owl has soft brown plumage above, mottled with grayish-white; undersides of light gray barred with dark; a "collar" of white feathers on the upper breast; a rust-colored face; and prominent ear tufts, the so-called horns, up to two inches long.

The great horned is known as the hoot owl for its call, 3-8 (usually 5) deep, booming, uninflected hoots: hoo-hoohoo hoo hoo. These owls hoot to stake out territory and as part of the species’ mating activity; which in Pennsylvania takes place in December or early January.

Great horned owls are believed to mate for life. They nest in crow, heron or hawk nests, tree cavities or hollow stumps and are the earliest nesters of all owls. A mated pair cleans debris from an appropriated nest, and the female then partly lines a central hollow with feathers. She lays two or three eggs at several day intervals, usually in February, and may temporarily get covered with snow while incubating.

Horned owls, especially incubating or brooding pairs, defend nests and young viciously and have even attacked humans who get to close. Eggs hatch in about a month; nestlings are downy-white, weak and blind. The young can not fly until they are almost three months old and contour feathers have grown.

Great horned owls prey on rabbits, wood rats, mice, birds, hares, domestic poultry, grouse, squirrels, smaller owls, foxes, skunks (this species’ defensive spray apparently does not deter the great horned owl), domestic cats, weasels, and muskrats. In short, most animals other then the large mammals.

Favored habitats are heavily forested land, large woodlots and remote wilderness areas; the species ranges over much of North America. Horned owls are not often found in populated areas, apparently needing solitude for nesting. In Pennsylvania, the great horned owl is an uncommon resident in all seasons.