The Great Horned Owl (Bubo virginianus) stands as one of North America’s most iconic raptors, known for its powerful presence and adaptability across diverse environments. These majestic birds, often recognized by their prominent ear tufts and piercing yellow eyes, thrive in a variety of habitats from dense forests to urban edges. Whether you’re a bird enthusiast or simply curious about wildlife, understanding the Great Horned Owl’s habits provides valuable insights into raptor ecology. Their widespread distribution and versatile lifestyle make them a fascinating subject for observation.
Habitat
Great Horned Owls inhabit a broad expanse across North America, extending up to the northern tree line. They favor secondary-growth woodlands, swamps, orchards, and agricultural zones, while also occupying deciduous, coniferous, or mixed forests. In regions like the southern Appalachians, they show a preference for old-growth stands. Typically, their home range incorporates open areas such as fields, wetlands, pastures, or croplands alongside forested zones. In arid deserts, they utilize cliffs or juniper trees for nesting. Remarkably adaptable, Great Horned Owls appear in wooded parks, suburban neighborhoods, and even cityscapes, demonstrating their resilience to human-modified landscapes.
Forests
This flexibility ensures their presence in nearly every suitable North American ecosystem, contributing to their status as a common species.
Food
Possessing the most varied diet among North American raptors, Great Horned Owls prey on creatures ranging from small insects like scorpions to larger animals such as hares, skunks, geese, and fellow raptors. Mammals and birds dominate their menu, including rabbits, hares, mice, and American Coots, alongside voles, moles, shrews, rats, gophers, chipmunks, squirrels, woodchucks, marmots, prairie dogs, bats, skunks, house cats, porcupines, ducks, loons, mergansers, grebes, rails, other owls, hawks, crows, ravens, doves, and starlings. They occasionally consume reptiles, fish, invertebrates, and carrion to supplement their intake.
Mammals
Primarily nocturnal hunters, they strike from perches, pursuing quarry over woodland edges, meadows, wetlands, or open water. Daylight hunts occur during scarce food periods, and they may stalk ground prey on foot near bushes.
For deeper insights into owl behaviour, explore how these predators interact with their surroundings.
Nesting
Nest Placement
Great Horned Owls select elevated sites in trees like cottonwood, juniper, beech, and pine. They repurpose nests from species such as Red-tailed Hawks, crows, ravens, herons, or squirrels, or opt for tree cavities, dead snags, abandoned buildings, cliff ledges, and artificial platforms. In the Yukon, they favor white spruces with fungal-induced “witches’ brooms.” Ground nesting happens rarely. Breeding pairs often roost near prospective sites months prior to egg-laying.
Tree
Nest Description
These nests, built from sticks, vary in size based on the original builder. Owls may add bark shreds, leaves, breast feathers, prey fur, or feathers, though some remain unlined. Nests degrade during breeding and are rarely reused.
Nesting Facts
| Clutch Size: | 1-4 eggs |
|---|---|
| Number of Broods: | 1 brood |
| Egg Length: | 2.1-2.2 in (5.3-5.6 cm) |
| Egg Width: | 1.8-1.9 in (4.5-4.7 cm) |
| Incubation Period: | 30-37 days |
| Nestling Period: | 42 days |
| Egg Description: | Dull white and nearly spherical, with a rough surface. |
| Condition at Hatching: | Helpless, with closed eyes, pink skin, and white down on upperparts. |
Behavior
Great Horned Owls roost in trees, snags, dense brush, cavities, ledges, or structures during the day, peaking activity at dusk and dawn. Food shortages prompt extended evening-to-morning hunts, including daytime in winter. Monogamous pairs defend territories with intense hooting in late fall and pre-breeding winter. Threats elicit bill-clapping, hisses, screams, wing-spreading, and talon strikes; they may even kill conspecifics. Crows, ravens, songbirds, and raptors mob them aggressively. Eggs and young face predation from foxes, coyotes, raccoons, lynx, and birds. Pairs remain territorial year-round but roost apart outside breeding.
Aerial Dive (ground/talons)
Conservation
Rated of low concern, Great Horned Owls maintain stable populations across the Americas, adapting to habitat shifts if nesting options persist. The North American Breeding Bird Survey shows steady numbers from 1966-2019. Partners in Flight estimates 5.7 million breeding adults, scoring them 8/20 on the Continental Concern Score. Historical hunting ceased mid-20th century, though illegal takes linger. As apex predators, they impact species like Peregrine Falcons and Spotted Owls. Northern cycles mirror prey fluctuations, with risks from prey-accumulated pesticides.
Low Concern
In summary, the Great Horned Owl exemplifies raptor adaptability, from versatile hunting to resilient nesting. Observing these birds underscores the importance of preserving diverse habitats. Consult ornithological experts or resources like the Cornell Lab for personalized wildlife insights, and consider supporting conservation efforts to safeguard such remarkable species.
References
- Artuso, C., et al. (2013). Great Horned Owl (Bubo virginianus), version 2.0. In The Birds of North America (A. F. Poole, Editor). Cornell Lab of Ornithology.
- Lutmerding, J. A., and A. S. Love. (2020). Longevity records of North American birds. Patuxent Wildlife Research Center.
- Partners in Flight. (2020). Avian Conservation Assessment Database.
- Sauer, J. R., et al. (2019). The North American Breeding Bird Survey, 1966–2019. USGS Patuxent Wildlife Research Center.
- Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf.
