Aguilucho Pálido

Identificación

The hen harrier is 41–52 cm (16–20 in) long with a 97–122 cm (38–48 in) wingspan. It resembles other harriers in having distinct male and female plumages. The sexes also differ in weight, with males weighing 290 to 400 g (10 to 14 oz), with an average of 350 g (12 oz), and females weighing 390 to 750 g (14 to 26 oz), with an average of 530 g (19 oz). Among standard measurements, the wing chord is 32.8 to 40.6 cm (12.9 to 16.0 in), the tail is 19.3 to 25.8 cm (7.6 to 10.2 in) and the tarsus is 7.1 to 8.9 cm (2.8 to 3.5 in). It is relatively long winged and long tailed.<p>The male is mainly grey above and white below except for the upper breast, which is grey like the upperparts, and the rump, which is white; the wings are grey with black wingtips. The female is brown above with white upper tail coverts, hence females, and the similar juveniles, are often called "ringtails". Their underparts are buff streaked with brown. Immatures look like females but with less distinct barring, dark brown secondaries dark brown and less-streaked belly.<p>The female gives a whistled piih-eh when receiving food from the male, and her alarm call is chit-it-it-it-it-et-it. The male calls chek-chek-chek, with a more bouncing chuk-uk-uk-uk during his display flight.

Taxonomía

In 1758 the English naturalist George Edwards included an illustration and a description of the hen harrier in the first volume of his Gleanings of Natural History. He used the English name "The blue hawk". Edwards based his hand-coloured etching on a bird that had been shot near London. When in 1766 the Swedish naturalist Carl Linnaeus updated his Systema Naturae for the twelfth edition, he placed the hen harrier with the falcons and eagles in the genus Falco. Linnaeus included a brief description, coined the binomial name Falco cyaneus and cited Edwards' work. The hen harrier is now placed in the genus Circus that was introduced by the French naturalist Bernard Germain de Lacépède in 1799. The genus name Circus is derived from the Ancient Greek kirkos, referring to a bird of prey named for its circling flight (kirkos, "circle"). The specific epithet cyaneus is from Latin and means "dark blue". The species is monotypic: no subspecies are recognised.<p>The hen harrier was formerly considered to be conspecific with the northern harrier.

Nombre científico

Circus cyaneus

Autoridad

(Linnaeus, 1766)

Orden

Accipitriformes

Familia

Accipitridae

Género

Circus

Distribución y hábitat

Breeding range: PAL : Europe and c, n Asia. Non-breeding range: s Asia and n Africa.

Área de cría

PAL : Europe and c, n Asia

Área no reproductiva

s Asia and n Africa

Migración

Migrantes completos

Comportamiento

Patrón migratorio: Migrantes completos.

Conservación

Tendencia poblacional: en declive.

Tendencia poblacional

en declive