The Harris' Hawk is a slim, long-legged, and quite docile hawk of the desert scrub in the American Southwest. It is a medium-sized to large hawk with brown body plumage, chestnut shoulders and legs, and a yellow face. Sexes are alike in appearance. It is swift in flight and graceful, often perching atop giant saguaro cacti in a diagnostic pose, holding its body quite horizontal. Common in groups, the Harris' Hawk both breeds and hunts in social units, which number among the members of adults, subadults, and juveniles from previous broods. This species is well known for having as many as three broods a year.
SIZE
The Harris' Hawk is the size of a large buteo hawk. Females are much larger than males. Lengths average 18 to 23 inches (46 to 58 centimeters) for both sexes. Wingspans are up to 46 inches (117 centimeters) for both sexes. Weights average 2.2 pounds (998 grams) for females and 1.5 pounds (690 grams) for males.
MORPHS
The Harris' Hawk has no morphs or unusual plumages.
SPECIFIC DESCRIPTION
Adult - Perched
- yellow cere and patch between beak and eye (lores)
- dark brown or blackish-looking body
- chestnut shoulders and thighs
- base of tail (both upper and lower surfaces) is white
- wingtips reach half way down tail
- long black tail with broad white band on tip and white base
- long yellow legs
Immature - Perched
- like adult, but upperparts dark brownish and belly streaked with white usually forming a bib with dark breast
- rusty and brown spotted shoulders
- whitish bars on rusty thighs; variants can have solid rusty thighs
- base of tail (both upper and lower surfaces) is white
- uppersurface of tail is black with white band on tip (narrower than adult)
- undersurface of tail is gray with darker bands and a white band on the tip
- wingtips reach half way down tail
- tail appears longer than in adult
- long yellow legs
SIMILAR SPECIES
The two other large black hawks of the Southwest, the Zone-tailed Hawk and the Common Black-Hawk, have blackish, not chestnut wing linings. Both have black-and-white banded tails, not a black tail with a white base and a white tip. Virtually all dark-morph buteos lack the chestnut wing linings combined with the dark tail with its white base and white tip of the Harris' Hawk. A dark Ferruginous Hawk has rusty wing linings and a dark body, but shows a whitish tail and whitish flight feathers from below. A Red-shouldered Hawk shows reddish wing linings but has a black and white banded tail, barred flight feathers, and a lighter body color. The immature White-tailed Hawk is superficially similar to the Harris' Hawk but has cold dark brown body plumage with a large white breast patch, and lacks the Harris' Hawk's chestnut shoulders. Its upper tail surface is gray with fine black bars, a thin white tip and a narrow white rump totally unlike the broad white base, black tail and white tail tip of the Harris' Hawk. The subadult White-tailed Hawk has some rufous on the shoulders, but less of it than the Harris' Hawk, and also has a white back and is white below with dark barring. The Snail Kite has a similar white base to the tail but shows all dark underwings, and no chestnut shoulders or under wing linings.
OTHER NAMES
The Harris' Hawk is also known as the "Bay-winged Hawk", "Eastern Harris Hawk", and "Dusky Hawk."
ETYMOLOGY
The scientific name Parabuteo unicinctus translates to "close relative of a buteo" (para - Greek; buteo - Latin) that has "one girdle or band" (uni - Latin; cinctus- Latin), a reference to the white at the base of the bird's tail.
MYTHOLOGY
No mythology is known for this species.
VOICE
The Harris' Hawk has a small repertoire of vocalizations. The alarm call is a scream, given as a "iirr", lasting up to three seconds. It also gives a Cooper's Hawk-like cackle at intervals for five to 10 seconds. During prey exchanges, or while anticipating a prey exchange or delivery, an "eerrp" call is given, lasting one to three seconds. Young begging for food give a plaintive "eechip" lasting about two seconds. A scream "oo-eek" has also been described, as have monotonous peepings given by adults.