Hudsonweihe

Bestimmung

The northern 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, having the longest wing and tail relative to its body size of any raptor occurring in North America.<p>The northern harrier breeds in North America, and its closest relative is the cinereous harrier (C. cinereus) of South America. The male's plumage is darker grey than that of the hen harrier, and the female is also darker and more rufous. The adult male is sometimes nicknamed the "Grey Ghost", because of his striking plumage and spectral aura.<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.

Taxonomie

In 1750 the English naturalist George Edwards included an illustration and a description of the northern harrier in the third volume of his A Natural History of Uncommon Birds. He used the English name "The Ring-tail'd Hawk". Edwards based his hand-coloured etching on a bird collected near the Hudson Bay in Canada and brought to London by James Isham. When in 1766 the Swedish naturalist Carl Linnaeus updated his Systema Naturae for the twelfth edition, he placed the northern harrier with the falcons and eagles in the genus Falco. Linnaeus included a brief description, coined the binomial name Falco hudsonius and cited Edwards' work. The northern harrier is now placed in the genus Circus, 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 hudsonius is from "Hudson Bay", the type locality. The species is monotypic: no subspecies are recognised.<p>The northern harrier was formerly considered to be conspecific with the hen harrier.

Wissenschaftlicher Name

Circus hudsonius

Autorität

(Linnaeus, 1766)

Ordnung

Accipitriformes

Familie

Accipitridae

Gattung

Zirkus

Verbreitung und Lebensraum

Breeding range: NA, MA : widespread. Non-breeding range: to South America.

Brutgebiet

Nord- und Mittelamerika: weit verbreitet

Überwinterungsgebiet

to South America

Zugverhalten

Vollzieher

Verhalten

Zugverhalten: Vollzieher.

Schutzstatus

Bestandstrend: rückläufig.

Bestandstrend

rückläufig