Species Spotlight: Great Horned Owl
Scientific Name: Bubo virginianus
What scientific order does this animal belong to? Strigformes
What scientific family does this animal belong to? Strigidae
Basic Description
Great Horned Owls are one of the most common owls in North America and are the owls often shown in storybooks. They have long, ear-like tufts, yellow eyes, and a deep hooting voice.
The owls have strong talons and can carry up to five pounds.
They have large eyes and have excellent night vision. Their eyes don’t move in their sockets, but they can swivel their heads more than 180 degrees.
Size and shape:
Great Horned owls are thick-bodied owls with two prominent feathered tufts on their head that looked like ears.
Their wings are broad and rounded.
Females tend to be larger than the males.
Males tend to have a deeper voice than the females.
Color pattern:
Mottled gray-brown, with reddish-brown faces and a neat white patch on the throat.
Overall color varies from sooty to pale, depending upon the region.
Behaviors
These owls are active mostly at night, especially at dusk and dawn.
The collective noun for owls is “a parliament”.
Mated pairs are monogamous and defend their territories with vigorous hootings, especially before egg laying or when their young leave the area.
Great Horned Owls respond to intruders or other threats will bill-clapping, hisses, screams and guttural noises. They eventually will spread their wings and will strike with their feet if the threat escalates.
Both members of a pair will stay in the territory outside of the breeding season, but they roost separately.
Habitats
Great Horned Owls roost in trees, snags, thick brush, cavities, ledges, and human-made structures.
Great Horned Owls can be found in deserts, wetlands, forests, grasslands, backyards, cities, or almost any other semi-open habitat between the Arctic and the tropics.
Feeding
Both parents share in the feeding. Typically the males hunt small mammals, which the female then tears into smaller pieces for the chicks.
Great Horned Owls are powerful predators that can take down other birds or mammals larger than themselves, but also dine on smaller fare like mice, frogs, and tiny scorpions.
Owls often swallow smaller prey whole. Their digestive systems have to deal with bones, fur, and feathers. Soft tissues pass through the owl’s gizzard to be digested, but indigestible bits like the bones, teeth, or fur are formed into an oval mass. This mass passes back up the digestive system and is regurgitated as a pellet hours after eating.
Inspecting these owl pellets can inform the citizen scientist about what owls are eating. Dissecting owl pellets is one of the more popular education modules at the Cache Creek Conservancy.
How many babies do Great Horned Owls have?
Clutch size: 1-4 eggs
Incubation 30-37 days
Nesting period 17-22 days, usually in winter months
Chicks leave when they are about six weeks old
How long do Great Horned Owls live?
In the wild the oldest Great Horned Owl on record was at least 28 years old, found in Ohio in 2005.
In captivity, one owl at the San Francisco Zoo lived to be 50 years old; typically captive Great Horned Owls live to between 20-30 years old.
Additional Links:
The Cornell Lab All About Birds
Nat Geo Wild video