Barn owl (Tyto alba)
It is a nocturnal raptor of medium size (35 cm, 300 gr.) easily recognizable for its white color and its characteristic heart shaped facial disc. Unlike other species, it has not tufts.
Its eyes are black and its bill, inconspicuous, is ivory color. The lower limbs are long and have feathered tarsus. Nails are dark. While in the field the underparts are apparently white, actually coloration of individuals varies from pure white to heavily mottled dark buff color. These differences may be due to age, sex and subspecies to which it belongs (see section Status and Distribution). Chicks are covered by a white down, which will be replaced by the juvenile plumage, very similar to adult.
The Barn Owl is an open areas species. Fields and crops, steppes or fallow lands are elected by this raptor as foraging areas. It chooses large holes to rest and breed, whether natural or man-made. Thus, we can find it in cracks and cavities of cliffs and rocky places, sometimes in holes of trees and more frequently in churches, old houses, barns, attics, etc.
It is a species closely linked to humanized areas because here it can find cavities near open areas equipped with abundant prey.
Estatus y distribution
The Barn Owl can be found in the Iberian peninsula and the islands.
The breeding iberian individuals behave sedentary and are supposed to belong to Tyto alba alba (white overall color and slightly mottled). During the harshest winters, individuals from northern Europe belonging to the guttata subspecies (darker and with larger spots on ventral parts) join our population.
The failure to award a subspecies to many individuals because of its intermediate coloration, and the existence of extremely dark chicks from pale parents, suggest the existence of hybridization between the two subspecies. In the eastern Canary Islands there is gracilirostris subspecies.
It is a species that maintains a fixed territory throughout the year. The size of the territory depends on the number of roosting places and prey availability.
Most adults remain matched in winter. It has two phases of activity: the first is shortly after sunset, and the other before sunrise. The hunt is carried out from a perch, or by glides and inspections by terrain with low flight. It gets the most of preys on the floor. They often follow regular routes, by the limits of forests, riverbanks, hedges between crops and uncultivated strips of vegetation between crops which have the highest density of small mammals.
Its flight is completely silent, as befits a species that efficiently uses the “directional listening” to locate prey.
Based mainly on small mammals (mainly voles and mice), it can supplement its diet with small birds. It specializes in certain food sources wherever they are accessible and plentiful, having registered selective predation on frogs or sparrows caught on night roosts.
Very studied. Dates are more determined by the availability of prey than for the time of the year.
Normally, the laying is performed on a layer of pellets during March-April, sometimes taking out a second and third laying later. This consists of 4-7 elliptical white eggs, placed at intervals of 2 or 3 days, only the female incubates and does so from the first egg. The eggs hatch after 32-34 days and the chicks will be covered in a first down the first 15 days, being replaced by a longer one. At this age chicks already swallow the whole prey and when they are 50-60 days old they are fully developed. Since there is an age difference of 2-3 days between chicks, cannibalism between brothers is common when food is scarce.
(Red Book of Birds of Spain)
“Of Special Interest” (National Catalog of Threatened Species of Spain)
Subspecies graciolirostris: “Endangered” (Red Book of Birds of Spain)