WESTERN BARN OWL

Tyto alba

English: Barn Owl.
German: Schleiereule.
French: Effraie des clochers.

Clasificación/Clasification

Order: Strigiformes.
Family: Tytonidae.

Longitud/Length

33-39 cm.

Envergadura/Wingspan

80-95 cm.

Aves relacionadas/Similar species

The Barn Owl is easily distinguished from other nocturnal raptors thanks to its dark eyes and white heart-shaped facial disk.

Sexo/Sexing

The adult male has pure white or small, speckled underparts with dark speckling restricted almost to the sides. The underwing coverts lack dark speckling, but if they have it, they are very small spots. A white neckband lacking an ante tone stands out on the neck. The back is light brown with little gray. On the other hand, the female has ante-stained underparts and usually has many speckles. The underwing coverts have dark speckling. The neck is stained with ante, although this tint lightens with age.

The back is dark brown with gray. Juveniles can be sexed using the same described characters, although care must be taken as there are many cases in which they cannot be sexed due to overlapping between individuals.

Edad/Ageing

It is possible to recognize 4 different ages:

Juvenile specimen: all flight feathers are of a single generation, that is, they do not show molt limits.

2nd/3rd year specimen: these individuals have some outerprimaries and inner secondaries moulted, so two generations of flight feathers can be seen. These specimens usually show molt of the central pair of rectrices.

3rd/4th year specimen: another change of a group of primaries and secondaries is present, so three generations of feathers coexist. For this reason, the feathers of the juvenile generation show great wear.

Adult specimen: two or three generations of flight feathers are seen in them, but none of them with a juvenile pattern. In these individuals, the pattern must be observed very carefully, as the design of the flight feathers of the adult and juvenile is very similar.

Muda/Moult

The molt processes of the Barn Owl, both post-nuptial and post-juvenile, are partial.

Configuración del plumaje/Plumage configuration

Primaries: 10 per wing.
Secundaries: 14-15 per wing.
Rectrices: 12.

Observaciones/Remarks

Link: http://blascozumeta.com/

La obtención de este material ha sido posible gracias al permiso necesario de la Junta de Andalucía.

AUTORIZACIÓN DE LA DIRECTORA GENERAL DE MEDIO NATURAL, BIODIVERSIDAD Y ESPACIOS PROTEGIDOS DE LA CONSEJERÍA DE AGRICULTURA, GANADERÍA, PESCA Y DESARROLLO SOSTENIBLE DE LA JUNTA DE ANDALUCÍA, PARA LA CESIÓN DE MUESTRAS BIOLÓGICAS DE ESPECIES DE FAUNA (ARTÍCULO 9 DE LA LEY 8/2003, DE 28 DE OCTUBRE, DE LA FLORA Y LA FAUNA SILVESTRES).

Medidas/Measures

Biometría/Biometrics

Adult specimen:
Beak tip to pupil center:
Tarsus:

Adult female specimen

1.- Right wing primaries. 2.- Primaries. 3.- Details of the primaries’ calamus. 4.- Details of the tip of the outer primaries. 5.- Details of the outer vane of the primaries. 6.- Details of the outer vane of P10, P9, and P8. 7.- Details of the outer vane of P10. 8.- Details of the tip of P2 and P1. 9.- Secondaries (S1-S7). 10.- Secondaries (S8-S14). 11.- Right wing secondaries and tertials. 12.- Details of the outer vane of the secondaries. 13.- Details of the secondaries calamus. 14.- Details of the tip of the secondaries. 15.- Details of the outer vane of the secondaries. 16.- Right wing tertials. 17.- Details of the tip of the tertials. 18.- Right wing primaries, secondaries, and tertials. 19.- Primaries, secondaries, and tertials. Primary coverts and secondary coverts. 20.- Primaries, secondaries, and tertials. Greater and median coverts + primary coverts. 21.- Primaries, secondaries, and tertials. Greater, median, and lesser coverts + primary coverts. 22.- Primaries, secondaries, and tertials. Primary and secondary coverts (G, M, and L). Alulas. 23.- Details of the primary coverts. 24.- Details of the tip of the primary coverts. 25.- Details of the secondary coverts (G, M, and L). 26.- Details of the lesser coverts. 27.- Primary coverts. 28.- Greater coverts. 29.- Alulas. 30.- Details of the major alula. 31.- Tail feathers. 32.- Tail feathers. 33.- Details of the tip of the central tail feathers. 34.- Details of the tip of the outer tail feathers. 35.- Details of the outer vane of the tail feathers. 36.- Details of R1 and R2. 37.- Tail feathers + uppertail coverts. 38.- Details of the uppertail coverts. 39.- Uppertail coverts. 40.- Tail feathers + undertail coverts. 41.- Infra-coverts primary. 42.- Assembly of the right scapula. 43.- Feathers of the right scapula. 44.- Assembly of the crown feathers. 45.- Crown feathers. 46.- Facial disc feathers. 47.- Details of the curvature of a facial disc feather. 48.- Feathers surrounding the beak and eyes. 49.- Assembly of the belly feathers. 50.- Belly feathers.

WESTERN BARN OWL

Medidas/Measures

Adult female specimen

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