Measurements
Both Sexes
- Length
- 16.9–24 in
43–61 cm - Wingspan
- 37–43.7 in
94–111 cm - Weight
- 17.1–27.3 oz
486–774 g
Relative Size
- Noticeably smaller than a Red-tailed Hawk; larger than a Broad-winged Hawk.
Other Names
- Buse à épaulettes (French)
- Bavil an ranero (Spanish)
Cool Facts
- Although the American Crow often mobs the Red-shouldered Hawk, sometimes the relationship is not so one-sided. They may chase each other and try to steal food from each other. They may also both attack a Great Horned Owl and join forces to chase the owl out of the hawk's territory.
- The Great Horned Owl often takes nestling Red-shouldered Hawks, but the hawk occasionally turns the tables. While a Red-shouldered Hawk was observed chasing a Great Horned Owl, its mate took a young owl out of its nest and ate it.
- Red-shouldered Hawks return to the same nesting territory year after year. One Red-shouldered Hawk occupied a territory in southern California for 16 consecutive years.
- By the time they are five days old, nestling Red-shouldered Hawks can shoot their feces over the edge of their nest. Bird poop on the ground is a sign of an active nest.
- The Red-shouldered Hawk is divided into five subspecies. The four eastern forms contact each other, but the West Coast form is separated from the eastern forms by 1600 km (1000 mi). The northern form is the largest. The form in very southern Florida is the palest, having a gray head and very faint barring on the chest.
- The oldest-known Red-shouldered hawk was at least 22 years, 5 months old. It was banded in Florida in 1989, and found dead in Florida in 2009, the victim of an attack by another raptor.
Habitat
Forest
Red-shouldered Hawks are forest raptors. In the East, they live in bottomland hardwood stands, flooded deciduous swamps, and upland mixed deciduous–conifer forests. They tend to live in stands with an open subcanopy, which makes it easier for them to hunt. They are not exclusively birds of deep forest, though; you’ll find Red-shouldered Hawks in some suburban areas where houses or other buildings are mixed into woodlands. In the West, they live in riparian and oak woodlands, and also in eucalyptus groves and some residential areas.
Food
Mammals
Red-shouldered Hawks eat mostly small mammals, lizards, snakes, and amphibians. They hunt from perches below the forest canopy or at the edge of a pond, sitting silently until they sight their prey below. Then they descend swiftly, gliding and snatching a vole or chipmunk off the forest floor. They also eat toads, snakes, and crayfish. They occasionally eat birds, sometimes from bird feeders; recorded prey include sparrows, starlings, and doves.
Nesting
Nesting Facts
- Clutch Size
- 2–5 eggs
- Number of Broods
- 1 broods
- Egg Length
- 2.1–2.2 in
5.24–5.65 cm - Egg Width
- 1.6–1.7 in
4.2–4.4 cm - Incubation Period
- 32–40 days
- Nestling Period
- 42–49 days
- Egg Description
- Dull white or faint bluish with brown blotches and markings
- Condition at Hatching
- Thickly covered with down; an even thicker down grows soon after hatching.
Nest Description
Both male and female build the nest, or refurbish a prior year’s nest. Stick nests are about 2 feet in diameter and lined with bark, moss, lichens, and conifer sprigs. The parents continue to add fresh green leaves throughout the nesting season.
Nest Placement
Tree
Red-shouldered Hawks often reuse nests from past years. Scientists don’t know which sex originally selects the nest site, although the male typically arrives back at the nest site first and defends the territory until the female arrives. They typically place their nests in a broad-leaved tree (occasionally in a conifer), below the forest canopy but toward the tree top, usually in the crotch of the main trunk. Nest trees are often near a pond, stream, or swamp, and can be in suburban neighborhoods or parks.
Behavior
Soaring
Red-shouldered hawks soar and circle with wings and tail spread out like a typical buteo hawk, but they also flap their wings quickly and glide through forests underneath the canopy, the way an accipiter such as Cooper’s Hawk does. When hunting, they perch near a wooded water body and watch for their prey to appear below them. In populated areas, such as forested suburban developments, they can become very unconcerned and approachable by people, but in wilder areas they flush easily. On their territories, Red-shouldered Hawks are aggressive, sometimes locking talons with intruding hawks and also attacking crows, Great Horned Owls, and even humans. As a mating display, the male enacts a “sky dance” in which he soars while calling, then makes a series of steep dives toward the female, climbing back up in wide spirals after each descent, before finally rapidly diving to perch upon the female’s back.
Conservation
Least Concern
Global populations of Red-shouldered Hawks appear to be stable, though populations in the East appear to have declined after forests were cleared. They are listed as endangered, threatened, or a species of special concern in many eastern U.S. states, with the most drastic declines occurring in Illinois, Iowa, Michigan, and Wisconsin, where numbers have fallen as much as 90 percent from historic estimates. Some populations have declined locally in the West, but the Red-shouldered Hawk’s western range has also expanded north into Oregon and east into pockets of Nevada and Arizona in recent years. The biggest threat to Red-shouldered Hawks is continued clearing of their wooded habitat; they also showed some sensitivity to pesticides such as DDT in the middle of the 20th century.
Credits
- Crocoll, S. T. 1994. Red-shouldered Hawk (Buteo lineatus). In The Birds of North America, No. 107 (A. Poole, and F. Gill, eds.). The Birds of North America Online, Ithaca, New York.
- Benyus, J. 1989. Northwoods Wildlife: A Watcher’s Guide to Habitats. NorthWord Press, Minocqua, Wisconsin.
- Dunne, P. 2006. Pete Dunne’s Essential Field Guide Companion. Houghton Mifflin, New York.
- Sibley, D.A. 2000. The Sibley Guide to Birds. Alfred A. Knopf, New York.
- USGS Patuxent Wildlife Research Center. 2011. Longevity Records of North American Birds.
Migration
Resident to medium-distance migrant. Birds of the Northeast and northern Midwest migrate to more southerly states for the winter. Birds in central and southern states don’t tend to migrate, although some Red-shouldered Hawks do spend winters in Mexico. Birds on the West Coast are mostly nonmigratory.
Find This Bird
One of the best ways to find Red-shouldered Hawks is to learn their distinctive whistle. Listen for these birds in and around wet forests, where you may find them hunting from a perch along stream or pond. In spring you may see Red-shouldered Hawks circling high above their nesting territory; they usually show pale crescents near their wingtips, where the sun shines through.