Endangered Resources Program Species Information
Barn Owl (Tyto alba)

Barn Owl Photo by C.F. Zeillemaker. Check the photos tab for additional photos.
Photo © C.F. Zeillemaker

Species information from the Bureau of Endangered Resources. See also:

Wisconsin Wildlife Action Plan Profile

Overview

Species Overview

Barn Owl (Tyto alba), a bird listed as Endangered in Wisconsin, inhabits open to partly open country, and prefers uncultivated field and wetland edges. It nests in buildings, caves and hollow trees. The breeding season extends from late March through late September.

Status and NHI Documented Occurrences in Wisconsin

The table below provides information about the protected status (State and Federal Status) and the rank (S and G Ranks) for Barn Owl (Tyto alba). See the Working List Key for more information about the abbreviations used. Counties shaded blue have documented occurrences for this species in the Wisconsin Natural Heritage Inventory database. For invertebrates, dots depict locations from the "Invertebrate Atlas," a database with occurrences of rare and common aquatic and select terrestrial invertebrate species found in Wisconsin and adjacent areas. While the invertebrate atlas is a quality assured database, not all records have been verified. The map is provided as a general reference of where this species has been found to date and is not meant as a range map.

Summary Information
State Status:	END
Federal Status in Wisconsin:	none
State Rank:	S1B,S1N
Global Rank:	G5
Tracked by NHI:	Y
Species of Greatest Conservation Need:	Y

Documented locations of Tyto alba in the Natural Heritage Inventory Database as of April 2009.

Detailed Information

Identification: What graceful, ghostly bird can locate a mouse by sound and catch it in the dark of night? The common barn owl, one of Wisconsin's best natural mousetraps.

Barn owls are sometimes called "monkey-faced owls" because of their distinctive, white, heart-shaped faces and small, dark eyes. These crow-sized owls are distinguished from other Wisconsin owls by a pale face, long legs, light, sometimes white/gray-spotted or black-speckled underparts and a rusty back speckled with black. Females are larger, heavier, and more speckled than males, and also have darker faces and larger spots on the breast and belly. Barn owls and other owls are classified in the same bird order (Strigiformes), but barn owls are in their own family (Tytonidae) because their skeletal structure and pale, stiff facial feathers differ from those of typical owls (Strigidae).

Barn owls don't have ear tufts like great horned owls or screech owls. But this doesn't mean barn owls don't have ears. Ear tufts are just feathers; the owl's real ears are behind its round facial disks, which help direct sound into the ears. Barn owls' ears also are asymmetrical; they are different sizes and one is located higher on the head than the other. This enables the bird to sense direction and distance by differences in the intensity of the sound that reaches each ear. Barn owls use their ears to locate food. They are very accurate hunters, even in the pitch black. Barn owls also have special feathers on the front edges of their wings that reduce the amount of noise they make when flying. Their quiet flight prevents prey from hearing them approach.

Hearing a barn owl's voice is unforgettable: "A shriek broke the stillness of the black night, a ghostly shadow passed by and my skin crawled." Not an overly flattering description of a barn-owl vocalization! Barn owls' high-pitched screeches or hiss-screams are memorable, but the birds are not harmful. They make these sounds to warn their young of danger, to announce their arrival at the nest and to proclaim their territory.

Habitat: Barn owls are distributed in grass habitats including wet meadows, lightly grazed pastures, hayfields and abandoned agriculture fields, hunting ranges occur along uncultivated field edges, fence rows and wetland edges, where their prey is most available. They nest and roost in dark, secluded places. During the winter, some adults wander locally while others migrate southward. Young owls generally move south the winter after they fledge and may return the following spring.

Natural Community Associations: The Wildlife Action Plan lists the natural community associations for this species.

State Distribution: In Wisconsin, barn owls generally live only in the southern third of the state as rare summer and winter residents. Since severe winter weather limits where they can survive, southern Wisconsin forms the northern edge of their North American range. They have been found in small numbers north to Polk, Clark, Vilas and Marinette counties.

Barn owls were placed on the Wisconsin Endangered Species List in 1979. At present, the status of the barn owl population in Wisconsin is unknown. The last reported nesting occurred in 1985, when a pair occupied a large silver maple in Deerfield (eastern Dane County).

Global Distribution: If you traveled to Europe or Africa, South America or Southeast Asia, Australia or North America, you could see barn owls. They live in temperate and tropical regions nearly worldwide.

Threats: Although Wisconsin's barn owl population was never high, a decrease in sightings since the 1950s suggests that it has been declining. No one factor has been clearly defined as the major cause for this decline. There appear to be several contributing factors:

Some modern agricultural practices have reduced barn-owl habitat. For example, shifts from cover crops such as oats and hay to row crops like corn remove food and shelter for mice and voles, barn owls' primary prey. Development of land, removal of hedgerows and draining of wetlands also have destroyed much barn owl habitat.
Fewer nesting sites may be limiting the barn owl population in Wisconsin. Modern metal farm buildings have few entry windows, which prevents them from being used by nesting barn owls. Woodlot management which removes large dead trees that have good nest cavities also reduces the number of possible nesting places.
Even though barn owls help farmers by eating large numbers of grain-consuming mice, they have been blamed for poultry losses. As a result, they are sometimes unjustly and illegally shot or poisoned.
Organophosphate insecticides cause poisoning in owls.

Diet: Why are barn owls called one of Wisconsin's best natural mousetraps? Because they eat 1.5 times their weight in food, mostly mice and meadow voles each day. That's like a 100-pound person eating 150 pounds of food every day! A barn owl family of two adults and six young may eat as many as 1,000 rodents during the nesting period. Although barn owls eat mice, meadow voles, shrews, rats and, when other food is scarce, small birds. They occasionally eat insects, amphibians and reptiles.

Nighttime is when barn owls hunt. Their excellent hearing helps them capture prey, which they usually swallow whole. They are unable to digest the fur, feathers or bones of the animals they eat, and cough up the undigested parts in a dark, odorless lump called an owl pellet. We can find out what an owl has eaten by examining the remains in the pellet.

Life History: When they are one year old, barn owls can breed. The male courts the female by chasing her, bringing her mice and uttering a series of rapid squeaking noises. A pair may use the same nesting site each year. Barn-owls select well protected nesting sites, usually in tree cavities of silver maple, American sycamore, and white oak, abandoned buildings, warehouses, church steeples, silos, grain elevators orand, the location that gave them their name, barns. Before settlement, barn owls nested in tree cavities and on cliff ledges.

Barn owls can breed year-round. In Wisconsin they usually rear a brood of young in the spring from March to July and, if food is plentiful, may rear a second brood in the late summer or early fall. Eggs are laid on a bare surface or, if the nest was used the previous year, on a thick mat of flattened pellets. The female lays an egg every two days until 5-7 white eggs are in the nest. When the first egg is laid, she begins incubating. Thus, when the first egg hatches about 30 days later, that owlet is older than the next one to hatch. It often is stronger and more able to take food from the parents.

Both adults hunt food for their snow-white, downy young. They bring prey to the nest, where the owlets swallow it whole. Sometimes the younger nestlings don't get enough food and die. The older, stronger owlets may even eat the weaker ones. Great horned owls and raccoons also eat young barn-owls. The young owls fledge when 8-10 weeks old.

Barn owls have difficulty surviving severe winter weather. Their bodies store little fat, so the birds have minimal extra energy to draw on when deep snow hides the small mammals they eat. If they don't find a constant supply of food, especially during cold spells when they use a lot of energy to keep warm, they may die. On average, barn-owls live 3-4 years.

Management Guidance: When research showed that the number of barn owls in Wisconsin was declining, the DNR recommended that barn owls be listed as a state endangered species and that action be taken to increase the barn-owl population in the state. Protection of grassland habitats and the installation of nest boxes in or adjacent to grassy habitats are effective conservation strategies. Since 1981, the Milwaukee County Zoo has bred barn-owls in captivity and the DNR has released them in southeastern Wisconsin. To date, 79 birds have been released, but it is not known if any have nested in Wisconsin. Researchers and volunteers are also building and installing nest boxes in suitable barn owl habitat. These nest boxes have been successful in Ohio and New Jersey, and hope is high that the boxes will be used by barn-owls in Wisconsin.

In 1985, DNR biologists began attaching radio transmitters to some of the owls it released. The transmitters broadcast a signal to receivers that allow researchers to locate an owl's daytime roost and monitor nocturnal movements. These and future studies will help provide needed information about how far barn-owls go to hunt, what kind of habitat they use and where they go after the nesting season.

Photos

Click on a photo to view a larger version. Please considering donating your photos to the Endangered Resources Program for educational uses. See also information regarding use of photos