The Chilean hawk (Accipiter chilensis) is a bird of prey species belonging to the typical hawks. It breeds in Andes forests from central Chile and western Argentina south to Tierra del Fuego, from sea level to 2,700 m[verification needed] altitude (though birds are rarely observed above 1,000 m). Some winter apparently in the lowlands of NW Argentina. It is sometimes considered to be a subspecies of its northern relative the bicolored hawk (A. bicolor), including by the American Ornithological Society and sometimes a distinct species. The two show differences in habitat preference and have allopatric distributions. But the situation is complicated by the subspecies pileatus, which is intermediate in plumage between bicolor and chilensis, and has been variously assigned to either species by those that consider them distinct. The male is 37 to 38 cm long, while the larger female measures 41 to 42 cm. The adults have black upperparts, and an ash-grey chest and abdomen with dark barring. The throat has longitudinal dark stripes and the undertail is white. The uppertail is brown with 5 or 6 dark bands. The legs are greenish yellow, and the eyes are yellow. The sexes have similar plumage.