Types of Owls

Owl species divide into two families the Barn Owls (Tytonidae) and the Tree Owls (Strigidae), based on physical differences. Generally the barn owls, like the one in the top picture, are characterized by long legs, a heart shaped face and small eyes.

Depending on the source, between 19-21 owl species, divided into eleven genera, are common residents of the United States. The Barn Owl is the sole Tytonidae representative.

• Barn Owl (Tyto alba)
• Boreal Owl (Aegolius funereus)
• Northern Saw-whet Owl (Aegolius acadicus)
• Long-eared Owl (Asio otus)
• Short-eared Owl (Asio flammeus)
• Burrowing Owl (Athene cunicularia)
• Great Horned Owl (Bubo virginianus)
• Snowy Owl (Bubo scandiacus)
• Ferruginous Pygmy-Owl (Glaucidium brasilianum)
• Mountain Pygmy-Owl (Glaucidium )
• Northern Pygmy Owl (Glaucidium gnoma)
• Eastern Screech-Owl (Megascops asio)
• Western Screech-Owl (Megascops kennicottii)
• Whiskered Screech-Owl (Megascops trichopsis)
• Elf Owl (Micrathene whitneyi)
• Flammulated Owl (Otus flammeolus)
• Spotted Owl (Strix occidentalis)
• Barred Owl (Strix varia)
• Great Gray Owl (Strix nebulosa)
• Northern Hawk Owl (Surnia ulula)

Most people share a passing knowledge regarding one of the two Bubo species, the Great Horned Owl (Bubo virginianus).

Often found living near residential areas, their natural range extends throughout all of North America, with a small South American presence.

Unlike other owl species, they are often active during daylight hours, especially early morning and later evening.

Yellow eyes and the feathery tufts on the head, along with their size gives them a unique look, and makes them easily identifiable. Great Horned Owls can stand up to two feet in length and have a wing span of five feet.

During the night hours, their call, the basic hoo-hoo-hoo-hoo-hoo, indicates their presence.

Like other owls, they hunt for local rodents and birds, occasionally capturing a small pet left alone.

Their widespread presence in North America means that their appearance changes slightly from region to region.

Snowy Owls (Bubo scandiacus) fit at the opposite end of the Buto taxonomy. A year round resident of northern latitudes, their feathers are predominantly white, which serves as camouflage in their environment.

They too are most active during day light hours. The extreme temperatures and lack of additional competitors in their territory account for the diurnal behavior.

Snowy owls occasionally migrate south to avoid the extreme Arctic winter conditions. From time to time, eruptions of wintering Snowy Owl populations extend into United States territory, when food supply problems in their normal winter territories run low.

They have a large established presence in the Eastern United States, while also extending their territory in the Pacific Northwest.

Because they are larger and more agressive than Spotted Owls, concerns continue to mount that they are adding additional pressure on declining Spotted Owl populations. The U.S. Fish & Wildlife Service recently released a revised Spotted Owl recovery plan that includes additional research on Barred Owl impacts on Spotted Owl populations.

Burrowing Owls (Athene cunicularia) are small migratory owls that live around and breed in ground burrows.

They are also an adaptable species, making their homes in both grassland and desert areas across the Western United States, except for the immediate coastal areas. They usually choose existing burrows dug by ground mammals or tortoises for homes, however some are known to dig their own burrows.

Burrowing owls not particularly adverse to interactions with humans, often living around human population centers.

The Spectacled Owl (Pulsatrix perspicillata) is a medium sized owl native of Central and South America.

The white feathers that surround the eyes explain the name.

They are active at night and live in both dry and tropical forests.

Some Owl Facts

The Elf Owl is considered the smallest owl in the United States.

The Great Gray Owl is considered the largest owl in the United States.

Owls have fourteen vertebrae in their necks, allowing them to turn their heads 180^o.

Owls have some of the best hearing in the bird world.

Anyone around a forest at night knows that owls are very vocal. Each owl species produces a set of self-identifying sounds. The stereotypical hooting sound is often accompanied by a variety of screeching and barking sounds.

Owls swallow their prey whole. The non-nutrition portions of the prey such as fur, bones, teeth and feathers, are excreted in the form of pellets.

© 2008-2013. Patricia A. Michaels