Poiana di Harris

Identificazione

This medium-large hawk is roughly intermediate in size between a peregrine falcon (Falco peregrinus) and a red-tailed hawk (Buteo jamaicensis). Harris's hawks range in length from 46 to 59 cm (18 to 23 in) and generally have a wingspan of about 103 to 120 cm (41 to 47 in). These hawks have a brownish plumage, reddish shoulders, and tail feathers with a white base and white tip.<p>They exhibit sexual dimorphism with the females being larger by about 35%. In the United States, the average weight for adult males is about 701 g (1.545 lb), with a range of 546 to 850 g (1.204 to 1.874 lb), while the adult female average is 1,029 g (2.269 lb), with a range of 766 to 1,633 g (1.689 to 3.600 lb). They have dark brown plumage with chestnut shoulders, wing linings, and thighs, white on the base and tip of the tail, long, yellow legs, and a yellow cere. The vocalizations of Harris's hawk are very harsh sounds.<p>The lifespan of Harris's Hawk is 10–12 years in the wild and 20–25 years in captivity.<p>The juvenile Harris's hawk is mostly streaked with buff and appears much lighter than the dark adults. When in flight, the undersides of the juveniles' wings are buff-colored with brown streaking. They can look unlike adults at first glance, but the identical chestnut plumage is an aid for identification.<p>There are three subspecies of Harris's hawk:

Tassonomia

Robert Ridgway placed Harris' Hawk in its own new subgenus Urubitinga (Antenor) in 1873, and introduced the generic name Parabuteo in 1874. Richard Bowdler Sharpe also separated Harris' Hawk to a monotypic genus, Erythrocnema, in 1874. In his Catalogue of Birds in the British Museum, Sharpe gives an extensive synonymy, with various authors having earlier placed harrisii in three genera and unicinctus in eleven.

Nome scientifico

Parabuteo unicinctus

Autorità

(Temminck, 1824)

Ordine

Accipitriformi

Famiglia

Accipitridae

Genere

Parabuteo

Areale e habitat

Harris's hawks live in sparse woodland and semi-desert, as well as marshes (with some trees) in some parts of their range (Howell and Webb 1995), including mangrove swamps, as in parts of their South American range. Harris's hawks are permanent residents and do not migrate. Important perches and nest supports are provided by scattered larger trees or other features (e.g., power poles, woodland edges, standing dead trees, live trees, boulders, and saguaros).<p>The wild Harris's hawk population is declining due to habitat loss; however, under some circumstances, they have been known to move into developed areas.

Migrazione

Specie stanziale

Comportamento

Comportamento migratorio: Specie stanziale.

Conservazione

Tendenza della popolazione: in diminuzione.

Tendenza della popolazione

in diminuzione