The White-tailed Hawk is a rather large hawk which lives in very open (coastal prairie) to sparsely wooded but open, arid regions, rarely used by other buteos. It has successfully colonized several Caribbean islands. In flight, its dihedral wing silhouette is similar to the Swainson's Hawk but it has rather long legs and a short tail. It is a striking bird with a white breast and white tail with a black subterminal band. Plumages of the adult and immature are very different, while the patterns of the subadult are between both in appearance. All ages have long legs and brownish eyes. In flight, all ages show dark primary feathers contrasting with paler secondary feathers.
It hunts from a perch while soaring or hovering.
SIZE
The White-tailed Hawk is a large buteo that displays reverse size dimorphism. The average total length for both sexes is 23 inches (58 centimeters) with a wingspan of 50 inches (127 centimeters). The average wing chord length for males is 16.4 inches (41.7 centimeters) and for females is 16.7 inches (42.4 centimeters). An average male weighs 2.1 pounds (950 grams); females 2.4 pounds (1,100 grams). Body size decreases from temperate to tropical latitudes.
MORPHS
Throughout its range, the White-tailed Hawk has been reported to have various shades of colors. These are dark immatures and subadults that apear very black. There are no color morphs reported in the United States. Adult plumage is attained in the bird's third year of life.
SPECIFIC DESCRIPTION
Adult - Perched
- crown and sides of head and neck dark ashy gray to neutral gray
- underparts, flanks, thighs and wing linings vary from brilliant white
- iris is dull yellow to sienna or hazel
- cere pale green to yellowish or yellowish olive
- bill black at tip, bluish gray at base
- diagnostic cinnamon rufous patch on upper wing marginal
- tarsi and toes bright yellow; claws blackish
- dark primaries extend noticeably (1 inch to 1.2 inches [2.5-4.0 centimeters]) beyond tail in
perched position, secondaries are paler, wings are pinched in at body
- distinct white tail with a wide black subterminal band
Subadult - Perched
- head, chin, throat, and back is black
- underparts generally darker than adult
- limited cinnamon rufous patch in the scapulars and inner wing coverts
- highly variable underparts from white to heavily streaked or barred with rufous and blackish;
anterior breast is always white
- wings extend considerably beyond tip of tail, like the adult
- tail is grayish with dusky subterminal band; uppertail coverts are white
Immature - Perched
- sides and nape of head have tawny-buff spots, otherwise head and chin are mostly dark brown
with some lighter streaks
- uniformly dark brown feathering on breast and abdomen
- cream to tan colored patch extends variably from throat to breast
- upperparts, including wings, are usually dark brown to blackish brown
- iris is usually dark brown as in adults and subadults
- bill black above and lighter below
- tarsi and toes flesh-colored, claws light brown
- tail is about 15 percent longer than adults
- tail is pale gray with numerous fine indistinct dark bars
- wings extend considerably beyond tip of tail
SIMILAR SPECIES
In flight, the silhouette of the White-tailed Hawk bears resemblance to that of the Swainson's Hawk. First year immature White-tailed Hawks are sometimes confused with Red-tailed Hawks, and some first and second-year immature White-tailed Hawks with "belly bands" resemble Red-tailed Hawks. Perched immature White-tailed Hawks can look like large, dark-morph buteos, but the wings extend far beyond the tails; in other species the wings are equal to, or shorter, than the tail.
OTHER NAMES
The White-tailed Hawk is locally referred to as the "Sennett's White-tailed Hawk", and simply "Whitetail."
ETYMOLOGY
The Latin word Buteo translates to "type of hawk or falcon"; the Latin prefix albus means "white" and the suffix caudatus means "tail."
MYTHOLOGY
There is no information for North America.
VOICE
This species has alarm calls which are usually described as a series of syllables, such as ke-ke-ke-ke, or kil-la, kil-la, kil-la. The first audible sounds given by young birds in the nest are believed to consist of short, sucking tsip, or tsick. Juveniles near nest-departure give a nasally begging call described as a peeeeee-up (= meow), which is often associated with hunger. From the second year onward, males give a short, nasally honking call which seems to be associated with excitement such as the presence of food.