Barn Owl Questions and Answers


Q: Where is the Barn Owl found in North America?
A: In North America, the Barn Owl has become rare
in many of it's former common locations. During the 1960's they were well distributed through out most of the United States wherever grasslands were abundant, and as far north as southern Canada. By 1980 the Barn Owl was not very common in the mid-western states, and almost completely gone from Canada. All States located north of the 41st parallel and east of the Rocky Mountains declared the species Endangered or Threatened by 1985. Today the distribution of the species in North America has dropped even further south, and it is considered rare in States east of the Rocky Mountains and north of the 39th parallel.

Q: What is the primary food of the Barn Owl?
A: The Barn Owl feeds mainly on the Meadow Vole, but also eats mice, shrews, and rats.

Q: How many voles do these birds consume per night?
A: Each Barn Owl usually consumes 6 voles or vole-sized rodents per night. This will equal about 1/3 of their total body weight in food consumption per night.

Q: What time of night is the Barn Owl most active?
A: Most hunting is done before midnight, with a second hunting period beginning about 2 hours before sunrise.

Q: Does the Barn Owl hunt during the day?
A: Very, very rarely. They are a strictly nocturnal species by nature, and those seen in the day have usually been flushed from the roost site, and are not hunting. Those seen hunting during the day are probably starving.

Q: Where do the owls go to hunt at night?
A: In most cases, these birds travel 1 to 2 miles from the daytime roost site to hunt. They hunt in roadside ditches, grassy fields, meadows, and swampy areas away from buildings.

Q: How many voles does an owlet eat each night?
A: For the first two weeks of age they eat from 2 to 4 per night. At three to five weeks of age they will consume 5 to 10 per night, per owlet! They will continue to consume about 10 voles per night until they are about ten weeks old, when the parents begin to slow down on the amount of food offered. This encourages the young to leave the nest to search for the parents, drop in weight, and eventually hunt for themselves at about twelve weeks of age.

Q: How does the Barn Owl locate prey?
A: They use their highly developed auditory senses to search for and locate the scurrying movements of voles in the grass. Their ear openings are fixed at counter positions on each side of the head, known as asymmetry. One opening is close to the front and set high, and the other is positioned further to the rear and lower. Both have small flaps faced forward, and aligned with the facial disk. The facial disk helps gather the sound to the flaps and openings. Each ear receives a different auditory frequency. The owl hovers over grassy fields with its head faced down, and listens. The noise created by the voles moving within the grass give off a wide range of auditory frequency, so each ear receives a different range of the spectrum. The position of the ear openings allow the sounds to reach each ear at slightly different times. The brain then calculates the distance of the sound source based entirely on the bi-angulation and frequency timings received by both ears simultaneously. When the location has been determined, the bird drops closer and takes a second reading, then drops upon the prey with its head tilted skyward and its feet very wide apart. The bird usually lands on the prey with at least one toe touching the prey, and it quickly grasps the prey. If the prey escapes, the bird will sometimes chase the prey on foot, but usually launches back into the air to relocate it. Therefore, although the Barn Owl can see very well in the dark, they rarely use their eyesight in search of prey. Eyesight is used primarily to locate perches and roosting areas.

Q: Does the Barn Owl hoot like other owls?
A: No, not usually. The most common vocalization is called the "Territorial" call which consists of a screech of about 2 seconds duration. In all, their are 17 different recognized Barn Owl vocalizations, but only about 5 are discernable by most people. Another common call is a "Churrrrrrrrrrrrrrrip" which resembles a woman’s shriek. At the nest site, the young offer the "Food Begging" call which is a drawn-out hiss that sounds very close to that of a Coleman Lantern (the gas sound). Bill snapping is also heard when the birds are disturbed at the nest. They also make a wide variety of chirps, chips, peeps, and snores while in the field or at the nest site. Very rarely a Barn Owl will make a quiet hoot, unlike the booming hoot of the Great Horned Owl.

Q: How can a Barn Owl fly over prey without the prey noticing?
A: They have silent flight. Their flight feathers are specially developed to allow air to pass through without making sound. Most owls of most species have developed silent flight.

Q: What is the nesting season for the Barn Owl?
A: The Barn Owl will breed in all months except January (North America). They will often produce two broods per year, and three in the southern sub-tropical regions.

Q: Where do Barn Owls Nest?
A: Most natural nest sites are in rotted cavities in very large and old oak trees, with a cavity depth of about 4 feet. Other natural nest sites include caves and cliff-bank holes of 4 or more feet in depth. Barn owls will also nest in barns and other buildings, in stacks of hay bales, and in man-made nest boxes.

Q: Why do these owls prefer nest boxes to hay bales or ledges?
A: The entrance hole cut in the box appears natural to them, while hay bales and ledges are used out of shear desperation. The dark interior of the nest box is similar to a natural cavity. It is instinctive for the Barn Owl to seek cavities to roost and nest in.

Q: How many eggs do they lay?
A: Usually 5, but sometimes 10 or more. One pair in Texas laid 27 eggs in a nest box, all of which hatched, and all of which fledged!

Q: How many owlets will survive to adulthood?
A: Not many. More than 60% of the fledged young (those that hatched and flew from the nest) die before they find a mate in the first year of life. The average lifespan for adults is 18 months. Of 100 adults, only one will survive to 10 years of age. Any Barn Owl reaching 5 years of age is considered old.

Q: If so many of them die every year, how do they maintain their population?
A: By producing large broods and having more than one brood per year.

Q: What is the common cause of death for the Barn Owl?
A: The Great Horned Owl and other Bubonidae species prey upon the Barn Owl. Secondly, death due to collision with fence lines, power lines, cars, trains, and trucks cause many Barn Owl deaths. Starvation plays a key role, especially in northern latitudes when snow covers the vole habitat areas. Predation by ground predators including skunk, opossum, fox and snakes is very common.

Q: What is a good way to help Barn Owls
A: Nest boxes. Placing nest boxes in areas where the birds can locate them will encourage the wandering juveniles to remain in these areas. Even where they are not common, the use of these boxes will eventually attract a wandering juvenile who will solicit a mate at that site. In areas where the Barn Owl is common, boxes placed for them will help them produce broods which will eventually wander into low population areas.

Q: If I put up a nest box and Barn Owls use it, should I look in periodically to count eggs and such?
A: If you do, make sure both adults are not in the box. If you disturb an incubating hen, or a hen with young during the day, she will begin to eat the young. If you plan to count eggs or young at a nest site, wait in a secluded and quiet area within view of the box or nest site until you see both adults leave the nest for nightly hunting. When eggs are present, the hen will leave for only about 30 minutes, so your visit must be quick. If there are owlets in the box, which will be evident by the food begging calls, both adults will leave to hunt. Make sure both are gone and out of sight. Have a plan developed to reach the nest and make your observation quick. Never attempt to monitor a nest during the day.

Q: What should I do if I find one of the owlets on the ground?
A: If it is alive and vigorous, keep it in a warm place until the night. Wait for the parents to leave the nest, and place the owlet back in with the others. If the hen does not leave, you have no choice but to place the owlet back regardless, although this is risky as mentioned above. If you find an injured fledgling, try to place it back in the nest, or call your local Wildlife authorities. At no time can you legally care for an injured owl without a special permit.

Q: How far should nest boxes be placed apart?
A: Because Barn Owl home-ranges often overlap, there is no magic placement distance. The more boxes placed within any 1700 acre area, the greater the odds that the owls will find and use them.