DEEP: Barn Owl Fact Sheet

Barn Owl Fact Sheet

BARN OWL
Tyto alba

{Barn Owl Illustration}
Copyright 1997
Habitat: Open areas, such as grassy fields, old fields, wet meadows and wetland edges, around farms and rural towns. Daytime roost is usually an evergreen tree, belfry or barn.
Weight: Males, 14-19 ounces; females, 17-25 ounces.
Length: Males, 13-15 inches; females, 14-20 inches.
Wingspan: Males, 41-45 inches; females, 43-47 inches.
Life Expectancy: Few adults live beyond 3-4 years; high mortality the first year.
Food: Meadow voles, mice and shrews; also bats, skunks and various birds; frogs and large insects only if necessary.
Status: State endangered.

Identification: The barn owl has a white, heart-shaped facial disk, no ear tufts and long legs. The bird appears white from below and golden-brown from above, with black specks all over. The long wings fold beyond the tail and the legs are feathered. The sexes can be distinguished by differences in coloration and weight. Males usually have whiter breasts with fewer and smaller dark specks. Females are typically heavier and have more and larger dark specks. Chicks are covered with down when born, but 8 to 10 weeks later they acquire adult-like plumage.

Range: The barn owl is found on every continent except Antarctica. The species is considered partly migratory in the northeastern United States, although many individuals remain there throughout the winter. Band recoveries indicate that some northeastern barn owls winter in Texas and the southeastern part of the country.

Reproduction: Barn owls are monogamous (one mate). They are not aggressive toward other barn owls and can nest within a half mile of other pairs. Barn owls are sexually mature at 1 year of age and, because they have a short lifespan, they breed only once or twice. Both natural and human-made sites are used for nesting and they are generally used repeatedly by other barn owls throughout the years. Nest sites include tree cavities, barns, abandoned and occupied buildings, and chimneys. Males use a courtship call to show the female the nest site. Barn owls do not construct a nest; the eggs are laid in a dark space surrounded by pellets. These brownish-black pellets, which are the regurgitated fur and bone fragments of each meal, average about 2 inches in size and are produced twice a day.

The 5-11 eggs (average 4-6) are laid every other day. The female incubates the eggs for 30-34 days, starting when the first egg is laid. Hatching occurs in the same order as the eggs were laid, so a gradation of ages and sizes can be observed in a brood. In times of scarce food, the older and stronger young have a better chance of survival. Stronger, first-hatched nestlings have been observed eating and trampling younger, later-hatched owls. The young are fed by both adults for approximately 2 months. The adult male does most of the hunting and feeding.

Reason for Decline: Land use changes, particularly the decrease in the number of farms, have contributed to the decline of this species. Not only has foraging habitat been reduced, but the increased use of rodent poisons has resulted in a smaller food base. Natural nest sites in hollow trees are often limited, and human disturbance of the nest during incubation may cause nest abandonment. One common cause of mortality is predation of young barn owls by raccoons. Other mortality factors include exposure to harsh weather, electrocution by power lines, predation by dogs and great-horned owls, and accidental entanglement in farm and industrial machinery.

History in Connecticut: The barn owl occurs in low numbers in Connecticut, probably because grasslands and farmlands are declining. The historic population status of the barn owl in Connecticut is unknown because the species is difficult to locate. Barn owls are principally found along the coast and within the large river valleys of the state. Breeding has been confirmed in coastal areas and near Middletown, where there is an active monitoring and nest box program.

Interesting Facts: The barn owl has exceptionally keen hearing and eyesight, making it a very effective hunter. It can see during the day, but its relatively small eyes (for an owl) are directed forward and are better adapted for night vision. The ears are asymmetrical; one is level with the nostril and the other is higher, nearer the forehead. They are covered with feathered flaps that close for loud noises and open for soft sounds. The barn owl's hearing is so sharp that it can easily hunt for voles and shrews, which are often concealed from view as they travel in runways beneath the grass. A family of 2 adults and 6 young may consume over 1,000 rodents during the 3-month nesting period.

Barn owls make a wide variety of sounds. The most common adult sounds are alarm shrieks, conversational calls (shorter, less intense shrieks), and a rapid squeaking or ticking, which is associated with the pair. The rasping, food-begging call of the young can be heard almost continuously from soon after sunset until just before sunrise. The young also hiss and bill-click when disturbed.

While perched, the barn owl has a habit of lowering its head and swaying from side to side. The bird sleeps so soundly during the day that it is difficult to wake it up until darkness arrives.

Other names for the barn owl are golden owl, white owl, monkey-faced owl and white-breasted barn owl.

Protective Legislation: Federal - Migratory Bird Treaty Act of 1918. State - Connecticut General Statutes Sec. 26-311.

What You Can Do: Learn more about owls by consulting references at your local library. Enjoy owls from a distance; do not disturb adults or young, especially during the nesting season. If you live near suitable foraging habitat, provide nest boxes for barn owls. Box plans are available from the Wildlife Division. Most important, encourage the protection of large areas of dense grass foraging habitats (at least 24-105 acres).

Connecticut Range

{Connecticut Range Map}

{Tax Checkoff Logo}
 
The production of this Endangered and Threatened Species Fact Sheet Series is made possible by donations to the Endangered Species-Wildlife Income Tax Checkoff Fund.
(rev. 12/99)