Harlan's hawk or Harlan's red-tailed hawk is a subspecies of the red-tailed hawk.
Description
While similar in linear dimensions to the western red-tailed hawk, this race is sometimes described as slighter and lighter. On the contrary, though, they are highlysexually dimorphic in size and mature females are sometimes more massive than almost any female B. j. calurus. However, B. j. calurus tends to have a much longer tarsus than Harlan's hawks do, as expected due to the latter's habitation to cold environments almost year around. The wing chord of males can range from, averaging, and, in females, it ranges from, averaging. Males and females average in tail length, in tarsal length and in culmen length. A wintering female in eastern Kansas weighed. The historic taxonomic status of Harlan's hawk has been quite erratic, sometimes it has been classified as its own species, B. harlani to the opposite extreme that R. S. Palmer classified as it as a mere western color morph. Most modern authorities recognize as a valid subspecies. Harlan's hawk is markedly different from all other red tails and can be identified nearly 100% of the time by an experienced hawk watcher. Throughout the morphs of this subspecies, the plumage is predominantly blackish, lacking any warmer or brownish tones. Harlan's hawks usually have faint streaks on the sides of their head and about their chest with a little gray mottling or speckling on the scapulars. Apart from a variably white-streaked throat, their underparts are usually mostly black with variable white streaking and barring on the thighs or crissum. There are up to four main variations from the typical one above: extreme dark morph, dark morph, rare pale morph and perhaps even rarer types where the base color is grayish. Unlike most red-tailed hawks, generally immatures are similar enough than adults that it can be difficult to distinguish them. On average, immatures have more extensive pale streaking above and mottling below, but much individual variation has been recorded. The typical tail of a Harlan's hawk is white with a thick black subterminal band but individuals may vary considerable and the tail may be reddish, dusky, whitish or gray and can be longitudinally streaked, mottled or barred.
Distribution
It breeds from centralAlaska to northwestern Canada, with the largest number of birds breeding in the Yukon or western Alaska, reaching their southern limit in north-central British Columbia. The Harlan's hawk is restricted as a breeder to pure taiga habitat. Harlan's hawk winters from Nebraska and Kansas to Texas and northern Louisiana, with a rare bird found as far east as Tennessee.
