The great horned owl is one of the most distinctive owls in North America. With prominent ear tufts, intimidating yellow eyes, and a deep hooting voice, these large predatory birds are a popular symbol of wilderness and wildlife. But what exactly makes the great horned owl such a unique bird species? Here we will explore some key traits that set great horned owls apart from other owls and birds.
Appearance
The most noticeable feature of the great horned owl is its striking appearance. These owls have large heads with prominent ear tufts, giving them a distinctive silhouette. Their yellow eyes are also quite striking against their plumage. Great horned owls have mottled brown and tan feathers across their upperparts and barred markings on their undersides. This camouflage helps them blend into tree bark and foliage. They have a wingspan of 3 to 5 feet and weigh between 2 and 5 pounds, making them one of the larger owl species in North America.
Key Identification Features
There are several key identification features to look for when identifying a great horned owl:
- Prominent ear tufts – These “horns” are made of feathers and are used to communicate and enhance their intimidating appearance
- Large yellow eyes
- Mottled brown and tan upperparts
- White throat patch
- Barred brown undersides
- Large, powerful talons
Habitat
Great horned owls occupy a wider range of habitats than most other owl species in North America. They are found across the continent from subarctic forests to tropical rainforests, deserts, grasslands, and even urban parks and backyards. Their adaptability allows them to thrive across diverse environments. They typically nest in the abandoned nests of other large birds, in tree cavities, or on rock ledges. Access to high perches and open areas for hunting are more important features than a specific habitat type.
Key Habitat Features
- Mature open forests with large snags for nesting
- Grasslands, meadows, and agricultural fields that provide hunting grounds
- Riparian areas that attract prey
- Cliffs, rocky outcrops, and human structures for nest sites
- Urban and suburban parks and neighborhoods
Diet
Great horned owls are opportunistic predators that eat a wide variety of prey. Their diverse diet is another key adaptation that allows them to inhabit so many different habitats. They most frequently hunt small mammals like rabbits, rats, mice, voles, and squirrels. But they also regularly prey on birds, reptiles, amphibians, fish, and large insects. They have even been known to take down skunks, cats, geese, and smaller owls. Great horned owls hunt at night by scanning the ground from an elevated perch and swooping down on prey with their large talons.
Key Prey Species
- Rabbits
- Hares
- Rodents
- Birds
- Reptiles
- Amphibians
- Fish
- Insects
Prey Type | Examples |
---|---|
Mammals | Rabbits, hares, rats, mice, voles, squirrels, opossums, raccoons, skunks |
Birds | Ducks, geese, grouse, doves, blackbirds, starlings |
Reptiles | Snakes, lizards, turtles |
Amphibians | Frogs, toads, salamanders |
Fish | Carp, catfish, bullheads |
Insects | Beetles, crickets, grasshoppers |
Breeding
Great horned owls begin breeding in late winter or early spring. They are monogamous and mate for life, returning to nest in the same territory year after year. Nests are made in the abandoned nests of other large birds or tree cavities. Females lay 1-3 eggs which incubate for about a month. The semi-altricial young hatch with downy feathers and stay in the nest for about two months while being cared for by the parents. They fledged from the nest at around 10-12 weeks but remain dependent on the parents for another few months.
Key Breeding Traits
- Early season nesters (beginning in late winter)
- Use existing nests instead of building their own
- Monogamous lifelong pairs
- Females lay 1-3 eggs
- Eggs incubate for about a month
- Young leave the nest at 10-12 weeks
- Offspring dependent for an extended period after fledging
Vocalizations
The deep, resonant hooting of a great horned owl is one of its most distinguishing features. Males establish territories and attract mates with their low-pitched hoots, often rendered as “hoo-hoo-hoo hoo hoo.” Females also hoot but at a higher pitch. Other vocalizations include a high-pitched screech, a startling hiss, bill-snapping, and low barks or growls. The wide repertoire of sounds is used for communicating different messages and interactions. Juveniles beg for food with a raspy screeching call.
Key Vocalizations
- Low, rhythmic “hoo-hoo-hoo” territorial hooting
- High-pitched screeching
- Hissing
- Bill-snapping
- Barks and growls
- Begging calls by juveniles
Range and Population
Great horned owls have one of the widest distributions of any owl species. They are found across almost the entire North American continent from northern regions into Central America. They can be found in lower populations in South America as far south as Tierra del Fuego. They are also native to a few Caribbean islands. Within their widespread range, they inhabit many types of ecosystems from coasts to mountains to deserts. Estimated population sizes are around 1.5 million birds in the U.S. and 15 million total across their range. Their populations are generally stable, and they adapt well to human activity.
Key Range and Population Traits
- Distributed across almost all of North America
- Also found in parts of Central and South America
- Occupy diverse ecosystems within their range
- Stable populations estimated at around 1.5 million in the U.S.
- Total estimated population of 15 million
- Adapts well to human presence and land development
Behavior
Great horned owls exhibit some interesting behaviors and adaptations. Their camouflage helps them skillfully ambush prey while their near-silent flight allows them to swoop in undetected. They have excellent low-light vision and incredible hearing that aids their nocturnal hunting. Their talons provide an extremely strong grip, allowing them to snatch large prey. They are territorial birds but are also often found perching or nesting fairly close to each other within overlapping home ranges. Outside the breeding season they may roost communally. Great horned owls rarely construct their own nests, often usurping existing nests from hawks, herons, or crows.
Key Behavioral Traits
- Ambush hunting aided by camouflage and near-silent flight
- Skilled nocturnal predators with excellent vision and hearing
- Powerful talons provide a deadly grip on prey
- Territorial but tolerant of proximity to other individuals
- Communal roosting in winter
- Take over existing nests instead of building their own
Adaptations
Over millennia, great horned owls have evolved specialized adaptations that make them fierce predators. Their camouflage and muted wing feathers allow them to blend in and fly silently. Their disproportionately large eyes are highly sensitive to low light. Their ears are directional and attuned to subtle sounds. Rotating their heads up to 270 degrees enhances their field of vision. Sharp talons and powerful legs equipped with sizable claws give them a deadly grip. These physical adaptations and honed hunting instincts allow great horned owls to thrive as predators.
Key Adaptations
- Camouflage and silent flight feathers
- Large eyes adapted to see at night
- Asymmetrical ear placement to precisely locate prey
- 270 degree head rotation
- Sharp talons and strong leg muscles
- Powerful grip strength in their toes
Threats and Conservation
While great horned owls still have extensive populations across North America, some localized threats affect certain populations. Habitat loss from human development removes nesting sites and impacts prey populations in some regions. Collisions with vehicles or aircraft also cause injury and death. However, great horned owls readily adapt to wooded suburban neighborhoods, limiting declines from habitat loss. Their diverse diet also provides resilience. While rodenticides and lead poisoning from eating shot prey can be risks, overall the species has maintained healthy numbers due to its adaptability. Their high reproduction rate also compensates for mortality. Currently the great horned owl is categorized as Least Concern by the IUCN.
Key Threats and Conservation Status
- Some localized habitat loss and fragmentation
- Vehicle and aircraft collisions
- Secondary rodenticide poisoning
- Lead poisoning from ingesting prey containing lead shot
- Classed as Least Concern on IUCN Red List
- Maintains stable populations across most of range
Conclusion
In summary, the great horned owl is a unique and iconic bird of prey thanks to its distinctive appearance, adaptability to diverse habitats, varied diet, early breeding season, deep hoots, vast range, and effective hunting adaptations. These traits allow great horned owls to thrive across a wide range of environments in North, Central, and South America. While localized threats exist in some areas, great horned owls remain numerous and continue their reign as one of the most powerful and recognizable raptors in the Americas. Their success as predators is a testament to the remarkable adaptations and behaviors that make the great horned owl one of a kind.