Arizona-Sonora Desert Museum Digital Library

Distinguishing Features

This is a long-legged, knock-kneed, pale, monkey-faced owl. It has no ear tufts, and the pale face resembles a heart-shaped disc. The back is golden-brown, the belly is white. The voice is a loud, rasping screech.

Habitat

This owl occurs throughout our area and through much of the U.S., Europe, Asia, and Africa. It is widespread but local. It is often found in conjunction with human habitation, roosting and nesting in barns, under bridges, in mine shafts, and in palm trees. It often nests in the undercuts of arroyos.

Feeding

• Diet: The Barn Owl feeds on large numbers of rats and mice.

• Behavior: An expert nocturnal predator, it finds its prey at night with exceptionally acute hearing and vision. The owl, like most birds of prey, ingests bone and fur when it eats its prey. However, the digestive processes of the owl are not capable of digesting bone and fur. This residual material is formed into a pellet in the stomach and regurgitated. Food habit studies of owls are easily done by examining the contents of the pellets found in or near their roosts.

Life History

Barn Owl nesting activity peaks in the spring, with five to six white eggs laid in a depression in a tree cavity, cave, mine shaft, or building. The female incubates the eggs about 33 days. The young remain in the nest for 7 to 8 weeks. The barn owl characteristically begins incubating the first egg, and while incubating it, lays additional eggs. Since the eggs are laid one to two days apart, the young hatch one to two days apart. Therefore, chicks of various ages (development stages) can be found in one nest. Often the older siblings starve out the younger. Once one dies, it is fed to the older nestlings. The young are very noisy, crying raucously when the adults feed them.

The Sonoran Desert at night is a very lively place. Especially in summer, there are probably more creatures abroad at midnight than at noon. Of course, most birds shun this night shift, but several species of owl are notable exceptions.

Owls are superbly equipped to hunt at night. They cannot see in total darkness— no animal can do that — but their eyes are adapted for vision under very low light conditions. Even more impressive is their sense of hearing. Studies have shown that Barn Owls can locate their prey by sound alone, in total darkness, with pinpoint accuracy. Many of the creatures that they hunt also have excellent hearing, but the owls can approach them in silence: the sound of their wingbeats is muffled by the softened edges of the larger wing feathers.

Great Horned Owls are found throughout the Americas and Barn Owls practically throughout the world, so it is no surprise that they can adapt to desert life. Great Horned Owls eat almost anything smaller than themselves from rabbits and skunks to snakes and insects. Barn Owls specialize on rodents and the smaller desert owls also tend to take small prey. The Ferruginous Pygmy-Owl, a tropical species that reaches its northern limit here, may hunt most at dawn and dusk, often catching songbirds. The world's smallest owl, the Elf Owl, nests in holes in saguaro cacti and ventures out at night to eat beetles and moths. Nocturnal insects are scarce in cold weather, so most Elf Owls retreat south into Mexico for the winter; other desert owls are present year-round.