Red-shouldered hawks are large, broad-winged hawks with a long tails and heavy bodies. Female red-shouldered hawks are larger than males. Female red-shouldered hawks average 700 g and 48 to 61 cm in length whereas males average 550 g and 43 to 58 cm in length. Adults have a wingspan of 92 to 107 cm (average 100 cm). Adult red-shouldered hawks have a brown head, a dark brown back and reddish underparts with dark brown streaks. Juveniles look similar to adults, but have creamy underparts with dark brown spots and streaks. Both adults and juveniles have reddish upper wing coverts (feathers), which make them look like they have red shoulders. They also have dark brown tails with white bands.
Red-shouldered hawks are found in the Nearctic region. They breed throughout the eastern and northeast United States into southern Canada, and west of the Sierra Nevada in California. Populations of red-shouldered hawks in the eastern U.S. and California are resident. Populations that breed in the northeast U.S. and southern Canada migrate to northern Mexico for the winter. (Christopher, 1990)
Red-shouldered hawks live in forests and swamps. They build their nests 6 to 15 meters (20 to 60 feet) above the ground in the branches of hardwood trees in wet woodland areas. They prefer to have dead trees nearby, where they can perch and see the forest floor. (Callahan, 1974; Crocoll, 1994; Woodward, et al., 1931)
Red-shouldered hawks are monogamous and territorial. They perform courtship flights by soaring together in broad circles while calling, or soaring and diving toward one another. Males may also perform a "sky-dance" by soaring high in the air, and then making several steep dives. These courtship flights usually occur in late morning and early afternoon. (Crocoll, 1994)
Red-shouldered hawks breed once per year between April and July. They often use the same nest for several years, fixing it up each spring. The male and female both build the nest, which is large and deep and made from sticks, twigs, shredded bark, leaves and green sprigs.
The female lays 3 to 4 white eggs with brown or lavender blotches. This takes 2 to 3 days. The eggs are incubated for 33 days. The egg that was laid first hatches first. The nestlings are altricial, meaning that they are helpless and need to be cared for by the parents. The female broods the chicks for at least a week after they hatch. The male brings food to the nest for the female and nestlings during the nestling stage. Chicks begin to leave the nest at 6 weeks old, but are fed by the parents for another 8 to 10 weeks. Chicks become independent of the parents at 17 to 19 weeks old. After becoming independent, they may still roost in or near the nest at night. Red-shouldered hawks begin breeding when they are 1 year old or older. (Callahan, 1974; Crocoll, 1994)
Male and female red-shouldered hawks both protect the nest and incubate the eggs. The female broods the chicks during the nestling stage while the male does most of the hunting for the female and the chicks. Both parents feed the young during the nestling and fledgling stages. (Crocoll, 1994)
Wild red-shouldered hawks live an average of 25.6 months. The oldest known red-shouldered hawk lived 19 years and 11 months. (Crocoll, 1994)
Red-shouldered hawks are solitary and territorial. They do not form flocks, even in the winter.
Most populations of red-shouldered hawks do not migrate. They stay in the same area year-round. Red-shouldered hawks that breed in the northern parts of their range (the northeast United States and southern Canada) migrate to northern Mexico for winter. (Callahan, 1974; Christopher, 1990; Crocoll, 1994; Woodward, et al., 1931)
Male red-shouldered hawks tend to have larger home ranges than females. The home range of both sexes is usually larger during the non-breeding season than during the breeding season. Home ranges typically range from 1.0 to 3.4 square kilometers. (Crocoll, 1994)
Red-shouldered hawks use physical displays, such as courtship flights, and vocalizations to communicate. Biologists recognize seven different calls given by red-shouldered hawk adults. The most common call is "kee-aah". This call is used to announce that a territory is occupied, and when the birds are alarmed. (Crocoll, 1994)
Red-shouldered hawks eat small mammals as big as rabbits and squirrels. They also eat reptiles, such as snakes and lizards, and amphibians, including toads and frogs. They also eat small birds and large insects. Crayfish are an important food for red-shouldered hawks in some regions.
Red-shouldered hawks search for prey by perching on top of a tall tree or soaring over woodlands. When they sight prey, they kill it by dropping down onto it from the air. They may store food near their nest to eat later. There is no information available about how red-shouldered hawks drink water.
Red-shouldered hawks use sight and hearing to hunt successfully. They do not hunt by smell. Red-shouldered hawks have very sharp eyesight and broad wings which allow them to be very successful hunters.
Red-shouldered hawks compete with other large birds, including golden eagles, prairie falcons, red-tailed hawks, barred owls and great-horned owls for territories. They provide food for their predators; primarily great horned owls and raccoons. They also host at least one blood parasite (Leucocytozoa) and several external parasites. (Crocoll, 1994)
Though red-shouldered hawks usually eat rodents and other small mammals, they occasionally eat poultry, making them a nuisance to farmers. Many of these hawks are killed annually by farmers for this reason. Red-shouldered hawks are sometimes called “hen hawk" because of this. (Callahan, 1974)
Red-shouldered hawks prey on rodents that are agricultural pests. (Callahan, 1974)
Before 1900, red-shouldered hawks were one of the most common hawk species in eastern North America. They have become less common because of hunting and destruction of their forest habitat. Red-shouldered hawks are also accidentally poisoned by insecticides. They often are not able to raise young when there is human disturbance, such as logging, near their nests.
This species is listed as threatened or endangered in several U.S. states, including Michigan. It is protected in the U.S. under the Migratory Bird Treaty Act. This species is also listed under CITES Appendix II. (Crocoll, 1994)
Kari Kirschbaum (author, editor), Animal Diversity Web.
Stephanie Miller (author), Cocoa Beach High School, Penny Mcdonald (editor), Cocoa Beach High School.
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Christopher, R. 1990. Book of North American Birds. Pleasantville: Reader's Digest.
Clark, W., B. Wheeler. 2001. A field guide to hawks of North America, 2nd Edition. New York: Houghton Miflin Company.
Crocoll, S. 1994. Red-shouldered hawk (Buteo lineatus). Pp. 1-20 in A Poole, F Gill, eds. The Birds of North America, Vol. 107. Washington, DC: The American Ornithologist's Union.
Whetmore, A. 1965. Water, Prey, and Game Birds of North America. Chicago: National Geographic Society.
Woodward, C., A. Howell, N. Mayo. 1931. Florida Birds. Tampa: Florida Grower Press.