Red-Tailed Hawk

Red-tailed Hawk

Scientific Name: Buteo jamaicensis
Alternate Name: Redtail
Size: length from head to toe 45-55cm;
wingspan 110-141cm; mass 710-1550g
Type migrant: partial

Introduction

The Red-tailed Hawk is characterized by variability and versatility. Across its widespread range, this species exhibits remarkable diversity in plumage, habitat use,  and hunting ecology, so much that the redtail is often described as a  jack-of-all-trades.”  The redtail is a large, stocky buteo found from central Alaska and Canada south to Panama. Redtails are numerous migrants at many watchsites throughout their North America range. The fact that they tend to perch and soar in open habitats and tolerate human-dominated environments makes them one of the most  frequently observed raptors in the region. The reddish or rufous tail of adults makes the species one of the most easily recognized raptors.

Red-tailed Hawks have adapted to human landscapes with isolated trees or small woodlots that provide nest sites and elevated perches for hunting, and their numbers have increased in North America in recent years. Human actions that have benefited the Red-tailed Hawk in the eastern United States include forest thinning and the  construction of the Interstate Highway System, both of which have created prime hunting areas. In the American West, fire suppression and power lines provide additional perches for hunting.

Red-tailed Hawks also have benefited from protection from human persecution. As recently as the middle of the 20th Century, the species was blamed for losses of poultry and was labeled the “chicken hawk.” As a result, redtails were commonly shot. The Red-tailed Hawk’s propensity to perch in the open made it particularly vulnerable to persecution.

Identification

The Red-tailed Hawk, one of the largest open-habitat raptors in North America, exemplifies the classic “buteo” configuration. It has a chunky body, broad wings, and a tail that is often spread or fanned in flight. The Red-tailed Hawk’s roundtipped wings and bulging secondary feathers make the species appear “muscular” in flight. When soaring, redtails typically hold their wings in a slight dihedral or shallow “V.” In North America, the redtail together with the Ferruginous Hawk and the Rough-legged Hawk, are the only buteos that regularly “kite” while facing into the
wind with their wings set.

The species varies in plumage across its range. Distinct differences exist between age groups, and among color morphs, and races. Individual redtails range from brown to black on their upperparts, and white to black  underneath. The tail, which can be solid rufous, or is banded brown, is sometimes streaked or spotted. Adults  typically have a reddish or rufous tail with a narrow, dark band at the tip. Compared with adults, juveniles have narrower wings and longer tails that are brownish with seven to nine dark brown bands of equal width. Dark morphs, which are common in the American West, are rare in the eastern United States. Adult light morphs have a dark brown head, back, and upperwing coverts. The underparts are pale cream or whitish with dark markings that often form a belly band. The underwings are pale with dark, rectangular patagial marks.

Breeding Habits

During the breeding season, soaring flight plays a major role in helping individuals establish and maintain nesting territories. When soaring, redtails can survey their territory and locate intruders. Migrants begin their aerial courtship displays in late winter and early spring. Sedentary birds (which remain paired throughout the year) engage in aerial displays throughout the year although most displays take place in early spring. During such breeding displays, pairs soar together in wide circles at high altitudes, and males often engage in steep dives and subsequent ascents. Males typically fly above and slightly behind the female, and sometimes the two interlock talons and spiral toward the ground.

Pairs either build a new nest or refurbish an old nest. Nests are constructed of two to three foot long branches that are usually less than half an inch thick. Both the male and female take part in nest building. When building their nests, redtails are secretive, and if disturbed, may abandon the site. Nest sites vary depending on available habitat, but in general they are open from above, and have a good view of the surrounding landscape. In forested areas, redtails usually choose to nest close to the trunk or near the tops of trees. Some individuals nest on cliffs and human  constructions such as powerline towers.

Redtails lay a total of one to five eggs with roughly 48-hour intervals between eggs.  The incubation period is 28 to 35 day begins shortly after the first egg is laid. The female does most of the incubation, and during this period the male feeds her. After the eggs hatch, the female broods the nestlings for 30 to 35 days, and the male continues to provide most of the food. Although both parents will bring prey back to the nest, only the female feeds the chicks. The young fledge at 44 to 46 days of  age, and the parents continue to feed their fledglings for another four to seven
weeks. During this time, the young gradually move farther from the nest, improve their flight abilities, and begin to hunt on their own. Some individuals remain with their parents for as long as six months after fledging.

Feeding Habits

Red-tailed Hawks are generalist predators that typically prey on small to medium sized reptiles, birds, and mammals up to the size of jackrabbits. Most concentrate their hunting efforts on species that are abundant and easily caught. As a result, redtail diets differ among regions, and across seasons, as well as among individuals. Most prey is taken back to a feeding perch where it is beheaded before it is consumed. Birds, even small birds, are usually plucked of their feathers, but small mammals are often swallowed whole. Redtails frequently feed on carrion, including
roadkills.

Although Red-tailed Hawks are commonly seen soaring, they are primarily perchhunters, and only infrequently hunt from soaring, kiting, or powered flight. Elevated perch sites appear to be a necessary component of suitable hunting habitat. A study in Arkansas indicated that Red-tailed Hawks preferred to hunt in areas with perches even though many of these areas had lower prey density than more open areas.

Bibliography and Credits:

Ash, Lydia M. “Falconry Birds.” The Modern Apprentice : Falconry Birds. Lydia M. Ash. 29 June 2009 .

“Raptor Life Histories.” Raptor Life Histories. 01 Jan. 2007. Hawk Mountain Sanctuary. 29 June 2009

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