Great Horned Owl

## Description

The Great horned owl (Bubo virginianus) is a large owl native to the Americas. It is an extremely adaptable bird with a vast range and is the most widely distributed true owl in the Americas. The Great horned owl is one of the earliest nesting birds in North America, often laying eggs weeks or even months before other raptorial birds.

## Appearance

The Great horned owl is a round-faced bird with a distinctive horn-shaped feather tuft on the crown of its head, which is darker than the rest of its head, promoting the overall camouflage. The owl possesses powerful, solid legs, feet, and claws. The Great horned owl has binocular vision due to its eyes, facing forward. The eyes of the horned owl are various shades of yellow. This bird can also be distinguished by the white colored patch on its throat. Black and brown stripes extend all over the white underbelly. The bill of the bird is black, surrounded by white or tan colored plumage. The plumage on their back is darker, covered with brown and black markings.

## Distribution

This owl is native to the Americas with its range, covering the greater part of North America, stretching to Central America and reaching South America. The Great horned owl occurs primarily in woodlands and open fields, scattered throughout its range. However, the species can also be found in mangroves, grasslands, swampy and marshy areas as well as desert. In addition, this bird occasionally inhabits human settlements, found throughout rural and urban areas.

## Behavior

These birds are solitary animals, socializing only for nesting. They usually roost by day in protected places such as a tree limb or a recess in a rock. Great horned owls are efficient nighttime hunters, though they are known to hunt in the daytime as well. Horned owls are non-migratory, remaining within the same area throughout the year. Some individuals may become "territorial floaters", not having a certain territory and constantly travelling through territories of other owls. These birds use hooting as a form of communication. Through hooting, they can search for mates during the mating season as well as set up territorial dominance.

## Diet

Great horned owls are carnivorous, feeding mainly upon terrestrial vertebrates. Typically, their preferred prey is cottontail rabbit. However, their diet consists of a wide variety of animal species, including shrews, jackrabbits, squirrels, muskrats, mice, domestic cats, scorpions, frogs, snakes, weasels, skunks, pocket gophers, bats, beetles and grasshoppers. They will also consume both small and large birds such as sparrows, juncos, grouse, wild ducks and pheasants. In addition, great horned owls can even eat other owls on occasion.

## Reproduction

They have monogamous mating system. Typically, the owl pairs are territorial, driving away other pairs from their territory in order to have full access to prey. By the mating season, the birds begin hooting with increased intensity, looking for mates. Female owls hoot only at this period while males normally hoot all year round. Breeding season takes place from November to April. The mating pair finds a nest, which is usually one, abandoned by a squirrel or another bird, including great horned owl. The female may lay up to 6 eggs with an average of 2-3. Both parents take part in the incubation for 30-35 days. After hatching, both male and the female provide the chicks with food. Young fledge by 6-9 weeks old, becoming independent at the age of 5-10 weeks. Sexual maturity is achieved at 1-3 years old.

## Population

### Threats

One of the major concerns is poisoning from pesticides and rodenticides, which farmers usually use in agricultural areas. Also, Great horned owls occasionally collide with electric wires as well as get into road accidents.

### Number

Currently, these birds are fairly widespread all over the area of their habitat. The overall estimated population of these owls in North and South America is about 5,300,000 individuals. Great horned owls are classified on the IUCN Red List as a species of Least Concern (LC) with a stable population.

### Ecological niche

Due to preying upon various small mammals, Great horned owls control the populations of these species, thus preventing possible spread of disease or excessive grazing throughout the range, and maintaining the health of the ecosystem.

## Fun Facts

In poor lighting conditions, they are capable of seeing about 35 times better than humans.

While humans have 7 neck bones, these birds possess 14 neck bones, which allow them to turn their heads up to 270 degrees.

When flying, this bird can remain unheard due to its comb structured feathers. The leading edge of the feathers has a kind of fringe, which allows the bird to avoid noise, when the feathers rub against each other, so that the prey target rarely hears the approaching of the owl before being caught.

Great horned owls are well known for the distinctive "who-who-who" call.

Not only do these birds have acute vision, but they are also able to prey, using only the sense of hearing.

The bill of the owl is hooked, allowing the bird to use its binocular vision without obstruction.

Unlike human eyes, the eyes of the Great horned owl are fixed, allowing the bird to look only forward, so that it has to turn its head to see peripherally.

The tufts on their ears serve as a mean of body language, which they use just like dogs: the ears lie horizontally when the owl is irritated, while stand upright, when the bird is inquisitive.