About 14-20 inches (35-50 cm) long. Unstreaked white or pale
cinnamon plumage on underparts with the back rust colored
(Peterson, 1990). The face consists of a heart-shaped facial disc
with relatively small dark eyes; the beak is a very pale yellow.
There are no ear tufts. The legs are long and slender, covered
with narrow feathers. The feet are bristled, with a comb-like
middle claw. The sexes appear similar; however, the female is
larger and generally darker than the male. With its long wings
and buoyant flight, it is almost silent in flight (Burton, 1984).
Tyto alba tends to live in woodlands, groves, farms,
barns, towns, and cliffs (Peterson, 1990). It prefers to live in
open and partly open country, often around humans.
This species is widely distributed in tropical and temperate
zones, including Europe, Africa, southern Asia, and Australia.
In the Western Hemisphere, it occurs from southern Canada to
Tierro del Fuego (Peterson, 1990).
The diet of the Common Barn Owl consists primarily of rats and
mice. Other small mammals, including small rabbits, are
occasionally eaten. Birds, bats, frogs, and large insects
supplement the diet when necessary (Burton, 1984).
Breeding begins early in the year and lasts until late summer. It
tends to take place in buildings, caves, crevices on cliffs,
burrows, and hollow trees (American Ornithologists' Union, 1983).
Since no nest is built, castings generally form a compact
barrier for the eggs; however, baskets or boxes may be used.
The nest is usually located on the floor in a dark crevice or
hollow. The clutch is normally 3-5 eggs, but may range up to 11,
laid at 2- to 3-day intervals. These eggs are white at first,
becoming stained yellowish. The female is responsible for most of
the incubation, beginning with the first egg; the male feeds the
female during this time. Hatching occurs after 33 days. Both
parents feed the young (Burton, 19840). The pulli seldom fledge
in less than 11 weeks (Fisher & Peterson, 1977).
The Common Barn Owl has been divided into 34 geographical races.
Fossil evidence suggests an origin 12 million years ago during
the Miocene Epoch. T. alba usually is a territorial
nocturnal hunter, yet at times it will hunt during the day,
flying only a few meters above the surface (Burton, 1984). The
voice has been described as a shrill rasping hiss or snore
(kschh or shiiish). There may also be an eerie
screech that is long and drawn out (Peterson, 1990). In flight,
the voice may be more of a get-get (Burton, 1984).
In common with other owls, undigested fur and bone is
regurgitated as castings ("owl pellets"), rather than being
passed through the complete digestive system.
American Ornithologists' Union. 1983. Check-list of North
American birds, 6th ed. Allen Press, Lawrence, 877 pp.
Burton, J. A. 1984. Owls of the world: their evolution, structure
and ecology.Tanager Books, Dover, 208 pp.
Fisher, J., and R. T. Peterson. 1977. World of birds. Crescent
Books, New York, 191 pp.
Peterson, R. T. 1990. A field guide to western birds. Houghton
Mifflin Company, Boston, 432 pp.
Mary Kirschenbaum, July 1996.