Lake Milton Raptor Center

Red Shouldered Hawk

Buteo lineatus
Classification
  • Kingdom: Animalia
  • Phylum: Chordata
  • Class: Aves
  • Order: Falconiformes
  • Family: Accipitridae
  • Genus: Buteo
  • Species: Buteo lineatus
  • Geographic Range

    Nearctic: Buteo lineatus resides in the eastern woodlands and the area west of the Rocky Mountains in the United States. The red-shouldered hawk is found year found in California and the eastern United States. It can also be found in New England and the Great Lakes Region during the summer.

    Physical Characteristics

    The Red-shouldered hawk is a large, broad-winged hawk with a relatively long tail and heavy body. Buteo lineatus demonstrates reverse size sexual dimorphism. The average male is 18.3 inches long, whereas the average female is 20.3 inches long. The hawk generally ranges from 18 to 22 inches in length. While the female and male are very similar in appearance, the immature and adult Red-shouldered hawks do exhibit slightly different markings. A brown head and reddish lesser secondary upper wing coverts, which give the semblance of red shoulders, are characteristic of both the adult and immature Buteo lineatus . The adult hawk has additional red markings on the breast and underwing coverts, while the breast and underwing of the immature Buteo lineatus are pale with light brown splotches. The tail of the both the immature and mature hawk is dark brown with white bands.

    Subspecies of Buteo lineatus exist in the different regions the hawk inhabits. The head and breast markings of the Florida subspecies, Buteo lineatus extimus and Buteo lineatus alleni, are slightly paler than other Red-shouldered hawks. The California subspecies, Buteo lineatus elegans, and the Texas subspecies, Buteo lineatus texanus, however, have vibrant, deep red markings on the lesser secondary upperwing coverts, underwing coverts and breast.

    Natural History

    Food Habits

    The diet of Buteo lineatus consists primarily of small mammals, the largest of these being rabbits and squirrels. The carnivorous hawk also consumes reptiles, such as snakes, amphibians, including toads, frogs and lizards, small birds and large insects.

    The red-shouldered hawk searches for its prey while perched on a treetop or soaring over the woodlands. The hawk kills its prey by dropping directly onto it from the air. Buteo lineatus is dependant on its senses of sight and hearing in hunting and does not hunt by smell. Some key characteristics that make the red-shouldered hawk especially well adapted to hunting include its sharp eyesight and broad wings. The hawk's large eyes are situated to look forward. Although the bird must turn its head completely in order to keep prey in view, the hawk's binocular vison grants it excellent depth perception. The high concentration of light-sensitive cone cells in the red-shouldered hawk's eye provides it with good resolving power and very sharp vision. The red-shouldered hawk is able to soar effortlessly for extended periods of time due to the combination of its broad wings and the wing slots in its primary coverts.

    Reproduction

    During the spring, the male red-shouldered hawks spread out and isolate themselves, defending their terrirories while attracting females with flight displays. During courtship, the red-shouldered hawks construct their nests.

    Fertilization is internal, as in all birds. The male hawk balances on the back of the female during copulation. The two birds then press their cloacae together and sperm is transferred from the male to the female. During copulation, the male stands firmly on both legs and rolls his talons into fists. This action prevents the male from accidentally injuring his mate.

    In February or March, the female lays about three or four whitish eggs with brownish yellow blotches.

    Behavior

    Although the red-shouldered hawk is a bold, aggressive bird, nesting hawks maintain a strong pair bond. The courtship behavior of Buteo lineatus is initiated by the male. The male demonstrates a call and flight display, which coordinates the male and female reproductive activites. Soaring high over the woodlands, the male dives dramatically, wings partially spread, and then quickly beats his wings to regain altitude. The male continues with his flight display until the female joins him or responds in some other manner. Nest building occurs during the time of courtship. Once the nest is completed, the male hawk places green sprigs around the edges of the nest to demonstrate ownership. While the female incubates the eggs, the male hunts and brings her food. After incubation, both sexes share in the hunting duties. The female, generally larger and heavier than the male, tends to catch the larger, slower prey, whereas the light, quick male hawk hunts smaller, more agile organisms.

    When not nesting, the red-shouldered is a solitary bird. It is also terrestrial, with a nesting and hunting territory of about 0.25 miles to 1 mile. This territory is aggressively defended during the spring. Males perform a threat display when other male red-shouldered hawks enter their territories. The Buteo lineatus call, which is loud and screeching, sounds like, "kee-yah kee-yah."

    Habitat

    The red-shouldered hawk makes its nest in deciduous forests and swamps. The bird generally nests about 20 to 60 feet above the ground, in the crotch of hardwood trees in wet woodland areas. Nests are large and deep, constructed from sticks, twigs, shredded bark, leaves and green sprigs. When not in its nest, Buteo lineatus often perches on the top of dead trees in order to have an unimpeded view of the forest floor.

    Red-shouldered hawks in New England and the Great Lakes Region migrate south during the fall, returning north when summer arrives.

    Biomes: temperate forest & rainforest

    Economic Importance for Humans

    Positive

    Buteo lineatus regulates the populations of its prey. Without raptors, such as the red-shouldered hawk, the populations of small mammals and reptiles and large insects would grow out of control. Buteo lineatus consumes many snakes that prey on the eggs of other woodland birds. Additionally, since it preys on rodents, the red-shouldered hawk is valuable to farmers.

    Negative

    Some red-shouldered hawks prey on poultry and game, making them a nuisance to farmers. Many of these birds are killed annually by farmers for this reason. Additionally, the nickname "hen hawk" for the red-shouldered hawk is a result of its tendancy to feed on poultry. Nevertheless, the primary diet of Buteo lineatus is not composed of poultry.

    Conservation

    Status: No special status

    Although substantial numbers of red-shouldered hawks are killed annually by farmers and game hunters, the bird seems to be maintaining a thriving population.