The Red-tailed Hawk (Buteo jamaicensis)

Aug 23, 2009 Features / Columnists, Interesting Creatures in Guyana

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The Red-tailed Hawk (Buteo jamaicensis) is a medium-sized bird of prey, one of three species colloquially known as the “chickenhawk,” though it rarely preys on chickens. It breeds throughout most of North America, from western Alaska and northern Canada to as far south as Panama and the West Indies.
Red-tailed Hawks can acclimate to all the biomes within its range. There are 14 recognized subspecies, which vary in appearance and range. Typically this hawk can weigh from 690 to 1600 grams (1.5 to 3.5 pounds) and measure 45–65 cm (18 to 26 in) in length, with a wingspan from 110 to 145 cm (43 to 57 in). It can display sexual dimorphism in size, with females averaging about 25 percent heavier than males.
Though the markings and hue vary, the basic appearance of the Red-tailed Hawk is consistent. The underbelly is lighter than the back and a dark brown band across the belly, formed by vertical streaks in feather patterning, is present in most colour variations. The red tail, which gives this species its name, is uniformly brick-red above and pink below. The bill is short and dark, in the hooked shape characteristic of raptors. The cere, the legs, and the feet of the Red-tailed Hawk, are all yellow.
Immature birds can be readily identified at close range by their yellowish irises. As the bird attains full maturity over the course of 3–4 years, the iris slowly darkens into a reddish-brown hue. In both the light and dark morphs, the tail of the immature Red-tailed Hawk is patterned with numerous darker bars.
The bird species is a member of the genus Buteo, a group of medium-sized raptors with robust bodies and broad wings. Members of this genus are known as buzzards in Europe, but hawks in North America and South America.
The Red-tailed Hawk is one of the most widely distributed hawks in the Americas. Its preferred habitat is mixed forest and field, with high bluffs or trees that may be used as perch sites. It occupies a wide range of habitats and altitudes, including deserts, grasslands, mountains, foothills of mountains, coniferous and deciduous woodlands, tropical rainforests, agricultural fields and urban areas.
The planting of trees allows the Red-tailed Hawk to expand its range by creating nest sites where there had been none. The construction of highways with utility poles alongside treeless medians provided perfect habitat for perch-hunting. As such it can also be found in cities.
In flight, this hawk soars with wings in a slight dihedral, flapping as little as possible to conserve energy. Active flight is slow and deliberate, with deep wing beats. In wind, it occasionally hovers on beating wings and remains stationary above the ground. When soaring or flapping its wings, it typically travels from 20 to 40 mph (64 km/h), but when diving may exceed 120 mph (190 km/h). When the Red-tailed Hawk walks, its steps are slow and awkward and it is generally non-aggressive toward people and toward other birds, unless there are nestlings present.
Approaching a Red-tailed Hawk with nestlings will result in attack and possible serious injury, so it is best to give the nest a wide berth. It is commonly harassed by crows, magpies, owls, other hawks, and even songbirds over territorial disputes, though it is generally not injured.
The cry of the Red-tailed Hawk is a two to three second hoarse, rasping scream, described as kree-eee-ar, which begins at a high pitch and slurs downward. This cry is often described as sounding similar to a steam whistle. It frequently vocalizes while hunting or soaring, but vocalizes loudest in annoyance or anger, in response to a predator or a rival hawk’s intrusion into its territory. At close range, it makes a croaking “guh-runk”. Young hawks may utter a wailing klee-uk food cry when parents leave the nest.
The Red-tailed Hawk is carnivorous, and an opportunistic feeder. Its diet is mainly small mammals, but it also includes birds and reptiles. Prey varies with regional and seasonal availability, but usually centres on rodents, comprising up to 85 percent of a hawk’s diet. Additional prey (listed by descending likelihood of predation) include lagomorphs, shrews, bats, snakes, waterfowl, fish, crustaceans and insects. Prey range in size from beetles to White-tailed Jackrabbits, which are double the weight of most Red-tails. It hunts primarily from an elevated perch site, swooping down from a perch to seize prey, catching birds while flying, or pursuing prey on the ground from a low flight.
The Red-tailed Hawk reaches sexual maturity at two years of age. It is monogamous, mating with the same individual for many years. In general, the Red-tailed Hawk will only take a new mate when its original mate dies. The same nesting territory may be defended by the pair for years. During courtship, the male and female fly in wide circles while uttering shrill cries. The male performs aerial displays, diving steeply, and then climbing again. After repeating this display several times, he sometimes grasps her talons briefly with his own. Courtship flights can last 10 minutes or more. Copulation often follows courtship flight sequences, although copulation frequently occurs in the absence of courtship flights.
The Red-tailed Hawk has a complex history with humans. The name “chickenhawk” was applied to the Red-tailed Hawk in earlier times, when free-ranging chickens and other domestic fowl were occasionally taken by these birds.

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