Tyto alba
(Common Barn-owl)

Order: Strigiformes
Order Description: Owls
Family: Strigidae
Family Description: Typical Owls

Physical Description:
14-20" (36-51 cm). Medium-sized owl. White, heart-shaped face ringed with tan with dark eyes and light bill; no ear tufts. White below, sparsely spotted black; golden tan back with fine pearl gray streaks; spotted black and white on crownClick word for definition, back, and wings.

Similar Species- Short-eared Owl, immature Snowy Owl

A loud, almost blood-curdling, rasping hiss.

Resident from southern Canada and northern U.S., south to South America. Northern populations are partially migratory.

Found in wide variety of situations in open and partly-open country. Frequently found around human habitation.

Eats mainly small mammals. In many areas (including southern Idaho), voles are principal prey. Pocket gophers, ground squirrels, pocket mice, kangaroo rats, and deer mice are locally important.

Nests in cavity in standing snag, cliff, or building. Breeding density depends on availability of nest sites and food supply. Young disperse widely from natal area (up to hundreds or 1900 km has been documented). Home ranges may overlap considerably where nest sites and prey are abundant. Individual remains solitary or paired when not breeding. Hunts mostly at night, from about 1 hr after sunset to about 1 hr before sunrise. May forage up to a few km from nesting or roosting site. Hunts mainly by quartering flights 1.5-4.5 m above ground. In northern winter, often roostsClick word for definition in dense conifers; also roosts in nest boxes, barns, and silos. Susceptible to starvation during prolonged low temperatures and snow cover. In Utah study, most adults survived only 1 breeding season. Great Horned Owl is principal predator in North America. Long-term study of breeding density and foraging ecology continues in Idaho Birds of Prey Area.

Breeds throughout year in Texas (as many as 3 broods/year); some California birds attempt 2 broods/year. Average clutchClick word for definition size is 4-6 eggs. Female incubatesClick word for definition eggs (21-24 days for single egg, 29-34 days for full clutchClick word for definition). Female broods and feeds young, male brings food. In Utah study, mean fledging time was 64 days. Male may care for fledged young as female begins second clutchClick word for definition. Most individuals apparently breed at 1 yr. Pair are typically monogamousClick word for definition with life-long pair bond; polygynyClick word for definition sometimes occurs.

Element Code: ABNSA01010
Status: Protected nongame species
Global Rank: G5
State Rank: S3
National Rank: N5

Important State References:
Marti, C.D. 1988. A long-term study of food-niche dynamics in the common barn- owl: comparisons within and between populations. Can. J. Zool. 66:1803-1812.

Design by Ean Harker©1999, 2000.
Written by Jason Karl, 2000.