Great Horned Owls can be found breeding from northern Alaska to the tip of Tierra del Fuego. Canadian birds seem to be somewhat migratory, responding to the population cycles of their prey, and move into the northern United States in winter.
Great Horned owls are monogamous. They usually choose an old hawk nest in which to lay 2 large, white eggs. Actual breeding is preceded by an interlude of hooting and visual displays between the two owls.
Mainly nocturnal, great horned owls can occasionally be seen during the day roosting in tall trees. Many people may never have seen a horned owl; however, most have heard their staccato, morse-code hooting: “hoo-hoo, hoo-hoo, hoo-hoo” on cold nights. Most calling occurs when courtship begins in October, with peak calling in November and December, often at dusk and after dark.
Occasionally, when Great Horned Owls kill more prey than they can eat, they cache the remains for later use. Great Horned Owls will incubate frozen food until it thaws and can be eaten.
Renowned for ferocity, Great Horned Owls kill and eat small to medium mammals of many kinds, especially hares and rabbits. They eat mice, rats, squirrels, opossums, woodchucks, bats, weasels, and the occasional domestic cat. Great-Horned Owls also eat skunks, which are sometimes such a prominent part of the diet that both bird and nest may smell of musk.
The great horned owl (Bubo virginianus) is a common year-round resident and the dominant strigiform on shortgrass prairie. [It was reported in 1992 ] higher numbers of great horned owls in northern Colorado than were found in the early 1970s, and suggested that the increase in owl numbers may affect other breeding raptors. Great horned owls respond numerically to increasing prey abundance, but there is no recent information on the diet of owls inhabiting shortgrass prairie or the distribution and abundance of prey.
[Observations in a study conducted by van Horne et al. in 1996] suggest that the owls foraged in relatively restricted areas, including roadsides, buildings and corrals, and along the narrow floodplain that comprises a small proportion ([less than]10%) of the total vegetation of the site. These areas have denser vegetation than the surrounding grassland and likely support higher rodent densities and perhaps, more lagomorphs.
Considered to be a benefactor from the habitat changes wrought by European settlers, [the Great Horned owl] is very common across its range today. Although federal statutes prohibit shooting or harassing Great Horned Owls, the birds are still persecuted by some for their predation of game birds and poultry.
The Great Horned Owl is the most common and widespread large owl found in the Americas. Its range spans much of the New World from the Arctic tundra to the tip of South America.
The Great Horned Owl, the fiercest and most powerful of the common owls, is visually stunning. It is sometimes called the cat owl because of its catlike ears, eyes, shape of head, and appearance when huddled up on its nest. The great horned owl is highly recognizable for the feather tufts on its head that resemble horns.