Taxonomy/Description

Barn Owls are in the order Strigiformes which consists of owls and in the family Tytonidae which which only includes the barn-owl. Many times Barn Owls are referred to as Common Barn Owls because they are one of the most widespread and distributed Barn-Owl, though they are not commonly seen. They are large (16inches, 41 cm), nocturnal, predatory birds. They are monochromatic which means that both males and females look alike. They have a white, heart-shaped facial disk, round head and dark eyes with rusty brown upperparts. Their underparts are white to buffy in some parts.

Photo M. Noonan

Habitat/Diet

Barn Owls can be found in most of North and Central America. Their northern borders are Washington, Iowa and Upstate New York. They are known to winter and breed in most of the United States. Populations found in the northern most ranges have been reported to be partially migratory. Barn Owls  prefer a wide diversity of habitats and the limiting factor is usually prey availability. They can be generally found in open habitats such as: grasslands, deserts, marshes and farmlands. There has been a decrease in number of Barn Owls due to loss of habitat. They are inconspicuous to most humans because of their nocturnal habits.

photo M. Noonan

Most of the diet of Barn Owls consists of small mammals such as: shrews, bats and leporids. They will also eat smaller birds, reptiles and amphibians, but are a smaller portion of the diet. Barn Owls seek their prey in a low searching flight.

Behavior/Reproduction  

Barn Owls hunt prey at night and because of this have adapted hearing that allows them to better sense their prey. A ruff of feathers is located just outside the ears which acts as a reflector to channels sounds into the ears. Once a sound is heard, the owl can pinpoint a location with 1.5 degrees in both the horizontal and vertical planes. Owls also have the ability to be silent hunters because of the structural modification of the first primary feather on each wing. The edge of the feather is serrated, instead of being smooth, which disrupts the flow of air over the wing in flight. This disrupts the vortex heard when air flows over a smooth surface.

Barn Owls have a monogamous mating system and usually have one brood per year. In courtship rituals, the male will clap his wings together and then ritually present food to his female. Barn Owls are cavity nesters and will use nest boxes or crevices as nesting sites. The female will lay 5-7 white eggs and incubate them for the 30-34 day period. The size of the  clutch depends on prey availability and the severity of preceding weather.  Hatching of the young is asynchronous and can span up to 14 days. The development of the young is semialtricial which means they are downy, blind, immobile and fed by their parents. Both parents will care for the young which are able to fly 52-66 days after being hatched. Fledging success is low following severe weather.