Barn Owl - Tyto alba

Barn Owl

Tyto alba

Order : Strigiformes

Family : Tytonidae ;

Biometrics :

Size : 33 à 39 cm
Wingspan : 85 à 93 cm
Weight : M: 470gr - F: 570gr

Longevity : 13 years

IUCN conservation status :

Extinct

Threatened

Least
concern

Extinc
in the Wild

Near
threatened

Not
evaluated

EX EW CR EN VU NT LC NE

Geographic range :

Synonyms : Sipukha (ru), Tornuggla (sv), Lechuza común (es), Barbagianni (it), Schleiereule (al), Kerkuil (nl), Barn Owl (en)

Physical description :
Barn Owl is medium sized owl, with long wings and distinctive head.
Barn Owl has pale brown upperparts, spotted with black and white. Rounded wings and short tail are white or light brown, with downy plumage. Underparts are greyish white. Long legs are sparsely feathered, down to the grey toes.
Head is large, with white heart-shaped facial disc, bordered with brown. It lacks ear tufts. Unlike many owls, eyes are dark. Frontal area is pure white. Bill is hooked and pale.
Female is larger than male.
Chicks are covered with white down for six days, gradually replaced by buff-coloured down.
Juvenile are similar to adults when down is lost.
We have up to 35 supspecies, with differences in body size and coloration.

Voice :
Sound from CD 'Tous les Oiseaux d'Europe' by Jean C. Roché by courtesy of Sittelle and CEBA. Barn Owl's alarm call is a hoarse hissing scream 'shrrreeeeee', also given in flight. Both sexes utter this call, but female's is weaker and lower-pitched than in male. Distress calls include drawn-out screams, given in series. Defensive call is a hissing sound. And they utter an explosive yell in front of mammalian predators. Barn Owls are more silent out of breeding period and courtship displays.

Habitat : Barn Owl lives in open country, cultivated areas with scattered trees, scrubs and hedgerows. It hunts along desert edges and canyons.
GEOGRAPHIC RANGE: Barn Owl lives in Americas, Europe, Africa, Arabia, India, South-eastern Asia and Australia.

Behaviour : Barn Owl feeds mainly on rodents, and mostly at night. It sweeps across fields on silent flight, and when prey is localized, it catches it with its long claws. It swallows the entire prey, bones, skull and all. It rejects pellets including the indigestible parts, at roost or near the nest.
Barn Owl uses its acute hearing to locate prey in darkness. Each ear may hear different sounds, allowing localising the rodent, without even seeing it. Barn owl may locate rodents making little noise in the grass, while is fluttering above the ground. Sounds are collected and brought to the ears by the facial disc, as a satellite dish. Their downy feathers allow them to be silent while they fly over fields, at about 1,5 to 4,5 metres above the ground.
Barn owl is solitary or seen in pair. It is a nocturnal bird, roosting in tree cavities during the day. It may also choose crevices, riverbanks, nest boxes or man-made structures. It is sedentary, with some northern birds migrating to south in winter.
To defend territory and nest against predators, Barn Owl spreads its wings and tilts them towards intruder. Then, it sways the head back and forth. While it performs this display, Barn Owl utters hisses and gives bill snaps, with squinted eyes. If intruder insists, Barn Owl falls on it and strikes with its feet.
Barn Owls are monogamous, with permanent pair bonds. Courtship displays include flights by male, accompanied by calls, and chasing female. During these chases, both adults screech. Male may perform 'moth flights' in front of female, hovering with feet dangling for several seconds. Both birds crouch down in front of each other, before copulation. Copulation occurs during the nest search, and continues decreasing during incubation and chick rearing.

Flight : Barn Owl has buoyant flight, with steady flapping, but it is wavering and also jerky as its body rises with each wing beat. Legs are often dangled in flight. Barn Owl flutters above the ground, searching for prey. It has silent flight.

Reproduction-nesting : Barn Owl nests in cavities, natural cavities such as trees or in rock crevices, in nest boxes, or in man-made structures. It may use an old nest, occupied for decades. Nest is lined with bits of pellets, by female.
Female lays 4 to 7 eggs, one egg every 2 to 3 days (sometimes up to 18 eggs). Incubation lasts about 29 to 34 days, by female, fed by the male. Chicks hatch altricial. Female broods and feed them during about 25 days. Male brings food at nest, but female alone feeds the chicks. She tears the food into small pieces. Both parents clean the nest.
Young fledge at 50 to 70 days of age, performing their first flight. They return to the nest to roost, for 7 to 8 weeks more. They become independent at about 3 to 5 weeks after begin flying. They reach their sexual maturity at one year.
This species produces one or two broods per year, sometimes three in southern parts of its range.

Food habits : Barn Owl feeds mainly on rodents such as voles, mice, shrews and rats. They also eat small birds, large insects and frogs.

Protection / threats : Barn Owls often die during the first few months of their life, for starvation, collisions, with fences, vehicles and buildings. They are killed by predators, such as Great Horned Owl, and other Owl species. Most adults do not live more than two years. They have also ground predators, such as skunks, opossum, foxes and snakes.
However, populations are maintained by large broods, and having more than one brood per year.

Other links :
Iucn
Birdlife

Specification sheet created by Nicole Bouglouan

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