Birds
Great Horned Owl
Bubo virginianus · also called tiger owl, hoot owl
The great horned owl is the classic owl of the night — the deep, rhythmic hoot from a dark tree line, the tufted silhouette against the moon. It is also the most adaptable and most formidable owl in the Americas, a predator so powerful and so broad in its tastes that almost nothing its size is safe from it.
Overview
Great horned owls range from the Arctic tree line to the tip of South America, in nearly every habitat that offers some trees or cliffs to nest and roost in and open ground to hunt over: boreal and deciduous forest, desert, sagebrush, swamp, grassland, mountains, orchards, farmland, and city parks. They are strictly nocturnal, hunting from dusk, and highly territorial, a resident pair holding the same ground year after year and announcing it with duetting hoots — the male’s voice lower than the female’s.
Built to kill
- Talons that clench with about 130 kg of force, killing prey instantly and holding it against any struggle.
- Silent flight — soft, comb-edged flight feathers muffle the sound of the wingbeat so prey never hears the strike coming.
- Asymmetrical ears hidden in the facial disc, which funnels sound; the offset lets the owl fix a mouse’s rustle in total darkness.
- Large forward-facing eyes with excellent low-light vision, fixed in their sockets, which is why the owl turns its whole head — up to about 270 degrees.
An unmatched diet
No North American bird of prey eats a wider range of animals. Great horned owls take mammals from voles to jackrabbits and young foxes; birds up to geese, herons, and other raptors, including ospreys, hawks, and smaller owls; snakes, lizards, frogs, fish, and large invertebrates. They are among the very few predators that habitually kill and eat skunks.
Nesting
Great horned owls do not build nests. They take over the previous year’s stick nest of a red-tailed hawk, heron, eagle, crow, or squirrel — or use a cliff ledge, cave, broken snag, or building — and lay two or three eggs in the depths of winter. The female incubates through freezing weather while the male hunts for both. The owlets leave the nest before they can fly, clambering onto branches (“branching”), and depend on their parents for months.
Status
The great horned owl is Least Concern and abundant, and it has benefited from the patchwork of woods and open land created by agriculture and settlement. Localised threats are the ones common to raptors — vehicle collisions, secondary poisoning from rodenticides, electrocution on power poles, and shooting — but none of these threatens the species overall.
Great Horned Owl: common questions
Do great horned owls have horns or ears on their heads?
Neither. The prominent tufts are just feathers, and they are not connected to hearing at all. Their function is thought to be camouflage — breaking up the owl's round outline so a roosting bird looks like a broken branch — and communication, since the owl raises and lowers them depending on its mood and how alarmed it is. The actual ear openings are hidden slits on the sides of the head, and they are placed asymmetrically, one higher than the other, so the owl can locate a sound in three dimensions.
How strong is a great horned owl's grip?
Its talons close with a force of roughly 130 kilograms per square inch — about ten times the strength of a human hand and enough to instantly kill or immobilise prey by crushing. Once clamped, it takes a force of several kilograms to pull the talons open. This lets the owl take animals as large as a full-grown rabbit, a skunk, a house cat, or another raptor, and carry off prey up to about three times its own weight.
What do great horned owls eat?
Almost anything they can catch. Their diet is the broadest of any North American owl and includes mammals from mice to jackrabbits and young foxes, birds up to the size of geese and other birds of prey (they regularly kill ospreys, peregrine falcons, and other owls), reptiles, amphibians, large insects, scorpions, and fish. They are one of the few predators that routinely eat skunks, apparently untroubled by the spray, and owls often smell strongly of it.
When do great horned owls nest, and why so early?
They are among the earliest-breeding birds in North America, laying eggs from late December to February, often while snow is still on the ground. Nesting early means the young hatch as prey animals — rabbits, rodents, and nestling birds — become abundant in spring, and it gives the slow-developing owlets a long stretch of the year to learn to hunt before their first winter. The owls do not build their own nest; they commandeer a large stick nest built the previous year by a hawk, heron, or crow.