Although it’s North America’s most prevalent owl species, the great horned owl’s healthy population is hardly noticeable to the average person. Even if it were to fly right beside you, there’s a great chance that you won’t notice a thing.
That’s because this predator is highly adapted for ultimate stealth. Its camouflaging stripes led naturalists to nickname it “tiger owl” — or tiger of the air.
Not only is it optimized for the hunt, but great horned owls also offer a diverse range of features that allow them to thrive in various regions. It’s no wonder this owl species has such a broad distribution!
One of the most noticeable features, and what gives this owl its official name, is its “horns.” It’s misleading to refer to them as “horns” or “ear tufts” since they technically are neither. These actually are patches of feathers that aren’t connected to the owl’s ears — and they’re officially called plumicorns.
Scientists aren’t entirely sure what the benefit of this adaptation is. However, one hypothesis is that plumicorns provide territorial and sexual cues between socializing owls.
The owl’s plumicorns work similarly to a dog’s ears — when great horned owls feel threatened or disturbed, their tufts lay flat. This, paired with its intense yellow eyes, provide a dead giveaway of the owl’s emotions.
Its eyes are fixed, but the owl’s exceptionally flexible neck helps expand its field of view. Contrary to common belief, owls can’t spin their necks around entirely but can certainly reach a 180-degree turn. They can also stretch their necks upwards and downwards for a better view of objects above and below.
Great horned owls have a weak sense of smell but compensate for it with acute eyesight. Their eyes have numerous rods, which optimize the bird for perfect night vision. Each eye features 3 eyelids, all with a different purpose — 1 for blinking, 1 for sleeping, and 1 for protection from debris during flight.
The forest-dweller’s feathers mimic the hues of its wooded region. Subarctic Canada’s great horned owls are almost entirely white. In the southwest, gray feathers speckle over an ivory backdrop. The Pacific Northwest’s birds wear deep sooty shades, while the eastern species don feathers in warm chestnut. A thicker plumage insulates those in cooler regions.
Also variable by region is the owl’s size, with females being the larger sex. The species’ weight ranges from about 2.5-5 lbs, with a length between 17-25 in. It’s the heaviest owl in Central and South America and the second-heaviest in North America — after its close relative, the snowy owl.
The great horned owl’s wingspan extends from 3-5 ft, depending on the subspecies. They have feathered legs and colossal talons that transfer up to 500 psi (pounds per square inch) of gripping force.
No matter the region, all great horned owls are equipped with facial disks. These are protractible feathers that form a bowl-like shape for channeling sound waves towards their ears. What’s more, the owl’s right ear sits higher than the left ear, giving it a sort of depth perception. This combined allows great horned owls to hear sounds up to 10 miles away!
Its wings are intricately designed for silent flight. The serrated feather edges cut straight through wind, preventing sounds from turbulence. Plus, its feathers are ultra-soft to help mute any additional flapping sounds.
This also allows them to coast as slow as 2 mph, which is impressive for a bird of their size. However, great horned owls can fly at about 40 mph at top speeds.
As adaptable as the great horned owl is, it does well in just about any environment across the Americas. Its range extends north to the Arctic tree line (Canada) and all the way south through Argentina. Although, like most owls, it doesn’t venture into the denseness of the Amazon Rainforest.
Its most common habitat is in deciduous and conifer forests, grasslands, tropical rainforests, tundra borders, deserts, agricultural areas, and sometimes suburbs.
As you may have guessed, the great horned owl’s features lend to its strictly-carnivorous diet. It’s a nocturnal hunter, preying on whatever warm meal it can get its talons on between dusk and nighttime.
Most of its diet comprises mammals; mice, rabbits, squirrels, opossums, and rats are among its favorites. Even skunks are no match for a great horned owl — their stinky defense mechanism doesn’t phase a bird with a weak sense of smell! Sometimes, great horned owls feed on insects, reptiles, amphibians, or even smaller birds (like ducks or hawks).
No matter the prey, it’s either swallowed whole or shredded into pieces by the owl’s razor-sharp beak. Nothing goes to waste as it gobbles down bones, fur, and flesh. About 10 hours later, the indigestible bits are regurgitated as neatly-packed pellets.
Parenting and Behavior
Great horned owls are non-migrational and guard their territories fiercely. They don’t hesitate to battle some of the most adept birds of prey, including falcons, raptors, ospreys, and even other owls.
Males and females communicate with alternating calls. It’s true that the female is larger in size, but the male has a bigger voice box, so its hoots are deeper than the female’s.
When pairs form, they remain monogamous and will return to the same mate each breeding season. But when breeding is over, they revert to a life of solidarity.
These owls are nest swipers. They overtake another bird’s (or even squirrel’s) already prepared nest and make themselves comfortable before the original owner gets a chance. This makes great horned owls one of the earliest nesters, often laying their clutch before the snow has melted.
Their preferred nesting sites are usually in trees/tree cavities, cliff edges, and other natural or human-made platforms. After snagging a nest, the owl typically lines the interior with soft material, such as leaves, fur, feather, or bark.
Clutches often comprise between 1-3 eggs, but sometimes 5. They are incubated mainly by the female owl while the male stands guard. Males are wildly protective over their young. To deter predators, they use a series of hisses and screeches as a warning. If that’s not enough, he aggressively pummels himself into the trespasser.
Great horned owl chicks wear a thick fuzzy down and receive food from both parents. They are ready for flight after about 10 weeks but have been known to escape the nest at around 5 weeks. The longest recorded lifespan of a great horned owl (in the wild) was 28 years.