Great Horned Owl

Meet Julio

Hatched: Spring 2000

Arrived at Audubon: Spring 2005

Sex: Female

Expected lifespan: 15-20 in the wild; 15-25 years in captivity

History: Julio was found as a nestling after the tree containing her nest was cut down. She was then raised by humans and never learned how to be an owl. By the time she was brought to the Wildlife Care Center at 5 years of age, it was too late to reverse the imprinting that had occurred. Releasing Julio back into the wild after she had imprinted on people would have put both humans and the owl at unacceptable risk.

It is illegal to keep great horned owls and other birds of prey as pets. It is important to get injured and orphaned wildlife to a rehabilitation facility as quickly as possible. Facilities such as Audubon have trained staff and volunteers, and they operate under special state and federal permits that allow them to treat wildlife. Julio will have a home for the rest of her life at Audubon, but if she had been brought to us sooner, we might have been able to set her free.

Julio - Tinsley Hunsdorfer

Species Fact Sheet

Scientific name
Bubo virginianus

Classification       
Class: Aves
Order: Strigiformes
Family: Strigidae
Genus: Bubo
Species: virginianus

Size
Male length: 17-22 inches
Female length: 18-25 inches

Male weight: 2-3 pounds
Female weight: 2.5-3.5 pounds

Male wingspan: 35-50 inches
Female wingspan: 45-60 inches

Appearance
There are about ten subspecies of Great Horned Owl in the bird's present range, and while they vary in size and color, the general appearance of each subspecies is similar overall. In the New World, only the Great Gray Owl and the Snowy Owl are larger.

The Great Horned Owl is characterized by large ear tufts, yellow eyes, an owl’s facial disk, a lack of a visible neck, and feathers down to the talons. As with most birds of prey, the females are larger in size.

Plumage varies from very dark in the Pacific Northwest to very pale in the Arctic. A typical adult is mottled gray-brown above, buff below, barred dark brown, with a tawny face and a distinctive white throat patch. Juvenile or immature owls are similar to adults but have a lighter or more rufous color until they mature. Their ear tufts are smaller and the white throat patch is less distinctive.

Range/distribution
The Great Horned Owl is a bird of the New World and has a present range that covers both North and South America from the Arctic to the Straits of Magellan.

Habitat/territory size
Habitats vary from woodlands to open country, urban parks to semi-deserts. The birds also live from low altitudes to high in the mountains, just below the timberline.

Migration
The Great Horned Owl is a non-migratory bird.

Diet
Great Horned Owls capture a wide variety of prey that ranges in size from mice to jack rabbits. They have been known to take prey as large as a porcupine, and they also eat fish, scorpions and a variety of birds, including the young of other raptors. These owls have even been found dining on skunks. The skunk’s odor has little effect in deterring the Great Horned Owl — like most birds, owls do not have a sense of smell.

Hunting method
Great Horned Owls are crepuscular, which means that they usually hunt at sunrise and sunset. They typically hunt from a perch.

Keen hearing would be useless if the owl itself made a lot of noise, so owls have evolved the ability to fly in nearly complete silence due to the soft fringes on the leading wing feathers. (Pygmy Owls are an exception.) When hunting, owls will glide silently down on unsuspecting prey. With this ability to fly silently, the Great Horned Owl is usually successful in capturing its prey.

Breeding

Great Horned Owls are solitary birds except during the breeding season, when they are found in family groups. Owls begin to pair up as early as December and raise only one brood each season. 

They are not very good nest-builders, so nests are often crude structures of sticks and twigs constructed in hollow trees or deserted buildings. They will often use abandoned hawk or crow nests instead of building their own.

The round-shaped eggs are laid at intervals, as often as every other day, with 2 to 6 being the average number. Owls begin to incubate the eggs from the time the first one is laid, so the young hatch at intervals and a nest may contain young of different ages and sizes. Both the male and female care for the nest, incubate the eggs, feed the young, and defend the home territory against intruders. The young remain in the nest until they are 9-10 weeks old and are able to fly. Afterwards, they follow the parents about and are fed by them until they can fend for themselves.

Behavior
The Great Horned Owl is said to be one of the fiercest of the birds of prey. Eastern ones are known to be more aggressive than the western representatives. This raptor has been known to drive Bald Eagles away from its nest.

Their vocalizations include the very distinctive low, hooting, who-who-whowhoho-whoo-whoo. The female voice is usually lower and deeper in tone that the males’. They will become much more vocal while courting.

The tufts of feathers on top of the owl’s head, which are called “horns” are not part of the ear apparatus, but they can be raised or lowered as an indicator of the owl’s mood and can be used in communicating with another owl.

Status
Great Horned Owls are the most common large owls found in North America. They are listed as a species of "least concern" on the International Union for Conservation of Nature's Red List.