Red-shouldered Hawk

The Red-shouldered Hawk is a medium-sized hawk of wet woods, and one of the most boldly marked in North America. An adult has rusty-red shoulders, underparts barred orange-red and white, flight feathers checkered black and white, and a black tail crossed by three or four narrow white bands. It is a buteo, one of the broad-winged soaring hawks, but a slim one, with a fairly long tail.

In flight, look for a pale, see-through crescent near each wingtip, at the base of the outer flight feathers; it glows when the sun shines through. From below an adult's wing looks two-toned, rufous wing linings against barred flight feathers. It often flies with a few quick flaps and a glide, like a Cooper's Hawk, and when gliding it holds its wingtips slightly forward. The eye is dark brown in adults, and the cere and legs are yellow.

A Red-shouldered Hawk is 17-24 in (43-61 cm) long with a wingspan of 37-44 in (94-111 cm) and weighs about 17-27 oz (486-774 g): about the size of a crow, clearly smaller than a Red-tailed Hawk and larger than a Broad-winged Hawk. Northern birds are the largest; birds in the South and West are 10-15% shorter.

Males and females look alike. Females are larger: in the Northeast males are 17-23 in (43-58 cm) long and females 19-24 in (48-61 cm), and females weigh about 25 oz (700 g) against 19 oz (550 g) for males.

Young birds look quite different. An eastern juvenile is brown above and whitish below with dark brown spots and streaks, heaviest on the breast, and its tail is dark brown with many fine pale bands. It has none of the adult's rufous or black-and-white, and its eye is gray-brown. The juvenile plumage is worn for about 18 months. See Juvenile Red-shouldered Hawks.

A young eastern bird looks a lot like a young Broad-winged Hawk. It has a longer tail and rounder wingtips, often flies with quick, accipiter-like flaps, and shows the pale crescent in the outer wing.

There are two separate populations. The eastern one breeds from southern Canada to Florida, the Gulf Coast and eastern Mexico; the western one lives in California and western Oregon and south into Baja California, about 1,000 miles (1,600 km) away. The subspecies look different enough to matter in the field.

Northern birds are the largest and darkest, and adults often have dark streaks on the breast. Birds of southern Florida are the smallest and palest, with a pale grayish to whitish head and pale barring below. California birds are the most richly colored, with a solid rufous-orange breast, brighter shoulders and wider white tail bands, and their young look much more like adults than eastern young do, more barred than streaked below.

The split runs deep. A 2019 genetic study found that eastern and western birds share no mitochondrial types, and that the Florida peninsula birds form a third group that meets eastern birds near Ocala; its authors consider the three separate phylogenetic species.¹ AviList, the global checklist, still lists one species with five subspecies, lineatus, alleni, extimus, texanus and elegans, the last the only western one.²

A Red-tailed Hawk is bigger and bulkier; most adults have a reddish tail, a dark belly band on pale underparts and a dark bar on the leading edge of the underwing. A Broad-winged Hawk is smaller and chunkier; adults have one or two broad white tail bands and pale underwings with a dark border. A Cooper's Hawk has short, rounded wings and a long, rounded tail, and adults are blue-gray above, never checkered. See Red-tailed or Red-shouldered Hawk?

The Red-shouldered Hawk is often heard before it is seen. Its call is a loud, clear kee-aah, stressed on the first part, the second part drawn out and falling. It comes in runs: one Wisconsin observer timed 5-12 calls between pauses, while a 1937 life history gives two to four, once 18-21 in a row.^{3, 4} The call announces a territory in early spring and is also an alarm, given at people near the nest and when a Great Horned Owl or Red-tailed Hawk turns up near it by day.

Eastern pairs are noisiest from courtship until the female starts to incubate, then become much quieter. In California adults and young call all year, most from November to May and above all from January to April. Seven calls have been described, among them excited kip notes, a long kee-ann-errr from displaying adults and a soft kee from a female on the nest, and one observer found females lower-pitched than males. At two nests watched, nestlings gave a short kee-aah at about two weeks old.³

Eastern Blue Jays often imitate the kee-aah almost exactly, so a Red-shoulder heard in a neighborhood may be a jay.⁵ Naturalists noticed long ago: a 1904 handbook lists the Red-shouldered among the hawks the jay imitates,⁶ and the 1937 life history says jays can closely imitate its cries, though with a difference a listener can recognize.⁴ In 1946 one writer doubted that such cases could be told from coincidence.⁷

Measured side by side in Ontario in 1987, a jay's Red-shoulder call lasted 0.47 seconds at 2-3 kHz, against 0.51 seconds for the hawk.⁸ In an informal New England survey published in 2004, 16 of the 44 people who answered had heard jays imitate Red-shouldered Hawks, and 16 Broad-winged Hawks, more than any other raptor.⁹ Two short notes from 1991 describe jays giving the call where other birds had food, one a second-hand report of a Florida grackle dropping its bread, which the jay ate; both are single anecdotes.^{10, 11} Why jays imitate hawks is not settled, and probably most do it for no particular purpose.¹² Steller's Jays, a western jay, copy the hawk too: in a 2024 study, 14 of 49 marked Steller's Jays gave Red-shouldered Hawk imitations.¹³

Look for Red-shouldered Hawks in mature woods near water: river bottomland forest, wooded swamps and stream sides in the East, and riverside and oak woodland in California, where they also use eucalyptus groves. They like tall trees with open space beneath the canopy, and hunt from a branch at the edge of a pond or stream. Many now live in wooded suburbs and parks.

The eastern population breeds from southern New Brunswick and Ontario west to the edge of the Great Plains and south to Florida, the Gulf Coast and eastern Mexico. The western population lives west of the Sierra Nevada from northern California to northern Baja California, and has spread into Oregon and Arizona by the 2000s. In the early 1900s observers feared the California birds were dwindling, but a 1970-72 survey found them throughout their old range and perhaps in some new places, some nesting in residential areas.¹⁴ Where Red-shouldered and Red-tailed Hawks share an area, studies in Iowa, Georgia and Indiana found Red-shoulders in bigger or more mature woods, nearer water and farther from development.³

Only partly. Birds from the northern part of the range move south for the winter, usually 190-930 miles (300-1,500 km); southern and western birds mostly stay all year. Eastern birds winter from southern Wisconsin, Ohio and southern New England to the Gulf Coast, a few to central Mexico.

In fall, young birds move from September and adults from October, with the peak in late October and early November in the Northeast. Spring passage peaks from late February to early April, and northern pairs are back on territory before frogs and snakes are about. Migrants follow ridges and, above all, shorelines such as the Great Lakes and the Atlantic coast, usually alone. Of the hawkwatches that count the most of them, Lake Erie Metropark, Michigan, had the highest autumn average in 2002-2007, about 980 a season.³

Red-shouldered Hawks eat small mammals such as voles, chipmunks and mice, frogs and toads, snakes and lizards, crayfish and large insects, and some birds. The mix changes from place to place and year to year: northern birds eat mostly small mammals, southern birds more frogs, toads and snakes.

At 20 nests in Arkansas in 2004-2005, amphibians made up 46% and invertebrates 33% of 1,139 identified prey items, and mammals only 6%; at four Massachusetts nests in the 1970s mammals were 72%. In Iowa and Arkansas, birds switched from mostly amphibians in one year to mammals or crayfish in another.³

Suburban birds take a similar range of prey. At 21 nests near Cincinnati, Ohio, watched for 256 hours in 1997-2001, small mammals made up 31.5% of identified prey, snakes 22.7%, invertebrates such as earthworms 18.8%, frogs and other amphibians 17.7%, birds 6.9% and fish 2.5%.¹⁵ See What do Red-shouldered Hawks eat?

Most hunting is done from a perch below the canopy or at the edge of a pond. The hawk sits still, watches the ground or the water, and swoops down; all of more than 250 hunts watched in southern California in a study published in 1993 began from a perch.³ In the open it flies low to surprise prey, and it sometimes snatches prey from the water surface or waits for a small mammal at its burrow.

In winter some take birds at feeders: one Wisconsin observer found Mourning Doves, House Sparrows and starlings often caught there, though small mammals are the usual prey. It has also been seen hiding prey near the nest.³

Pairs build a platform of sticks in a fork of the main trunk of a big tree, under the canopy yet above the tree's midpoint and often near water. Nests are usually 35-65 feet up. Both birds build, and they line the nest with bark, moss, lichen and conifer sprigs; it ends up about 18-24 in (45-60 cm) across, and fresh green leaves are added all season. Nests are often reused for years: in Wisconsin and Ohio single nests were used up to six years in a row.³

Laying starts in late January in Florida and early February in California, but not until late May in Canada; most eastern birds lay in March and April. The female lays 3-4 eggs in most of the East, fewer in Florida and California: dull white or faintly bluish, blotched brown and lavender. Incubation takes about 33-35 days and is mostly by the female; the male brings nearly all the food until the young are almost ready to leave, while the female broods and feeds them. The young leave the nest at about six weeks and may be fed for another 6-10 weeks. One brood a year.

Most do not breed until at least a year old, but some yearlings, mostly females, do: 9-10% of breeding females in two studies. Pairs are thought to keep the same territory for life, and a female in southern California kept the same territory for 16 years or more.³ See Red-shouldered Hawk nesting.

Many Red-shoulders nest in wooded suburbs. Near Cincinnati, Ohio, suburban nests averaged 250 feet (75 m) from a house and 280 feet (86 m) from a road, and a bird's 220-acre (90-hectare) breeding home range held on average 169 houses.¹⁶ From 1997 to 2016, suburban pairs in southern Ohio raised 1.54 young per nesting attempt and rural pairs 1.56, and the amount of housing around a nest made no difference.¹⁷ Active nests have even been found on two house roofs and a deck there.³

In California they nest in eucalyptus and other planted trees. Around San Jose in 1994-95, 14 of 27 and then 38 of 58 nests were in planted trees, mostly eucalyptus, which fledged young more often, and some nests were just 7 feet (2 m) from a building.¹⁸

Red-shouldered Hawks live alone or in pairs and rarely flock, even on migration. Near the nest they chase other hawks and owls, and some strike people who come too close: in suburban Ohio, unpublished data have birds hitting intruders with open feet at about 5% of nests.³ American Crows and Red-shoulders sometimes chase each other to steal food, and may mob a Great Horned Owl together. In wooded suburbs they can become quite tame; in wilder places they fly off at once.

In early spring pairs soar and circle over the territory with tails spread, calling. The male's sky-dance takes him high, calling; when the female appears he makes a series of steep dives, each ending in a wide spiral back up.

Most Red-shouldered Hawks live only a few years. Among 2,448 nestlings banded in suburban southern Ohio in 1996-2018, estimated yearly survival was 49% for young birds and 76% for adults, and half of those that settled did so within 6 miles (9 km) of where they hatched.¹⁹

The oldest Red-shouldered Hawk on the USGS Bird Banding Laboratory's longevity list was at least 25 years 10 months old: a female banded in California as a nestling in 1974 and seen alive there in 2000, when her marker was read. The next oldest, 22 years 5 months, was banded in Florida in 1989 and killed by another raptor there in 2009. The list holds only three birds.²⁰

Great Horned Owls and raccoons are the main nest predators; in western New York owls took 3 of 9 nests over two years.³ Red-tailed Hawks and Great Horned Owls may take over Red-shoulder nests, and in California, seeds of introduced grasses lodged in the eyes have starved birds; no other hawk seems to suffer this.³ Collisions and electrocution kill many: in suburban Ohio, of 38 banded birds whose cause of death was known, half were hit by vehicles and six were electrocuted, though birds killed near roads may be the likeliest to be found.¹⁹

Red-shouldered Hawks are listed as Least Concern worldwide.²¹ Partners in Flight estimates about 1.9 million birds, 1.8 million of them in the US and Canada, an estimate for about 2010.²²

Numbers have been rising. The North American Breeding Bird Survey shows an increase of 2.37% a year from 1966 to 2025 (95% credible interval 2.07 to 2.65), about a fourfold rise, and 2.72% a year from 2015 to 2025; no state or province shows a significant decline. Florida has by far the most per survey route. California rose 3.15% a year from 1968 but has dipped since a 2012 peak, a fall not statistically certain.²³

Numbers were once far higher. Clearing of the great eastern forests apparently cut them over the last two centuries, and estimates from 1979-1989 put populations in Michigan, Wisconsin, Illinois and Iowa at 90% below presettlement levels. Breaking woods into small pieces also favors the bigger Red-tailed Hawk and Great Horned Owl, which can take its place. In the early 1970s eggshells were 9-14% thinner in Maryland, California and Ontario, less than in many raptors, and the effect on breeding was unclear.³

Like the Red-tail, it was once called the "hen hawk", and like other hawks it was shot, with bounties paid in some states, though an 1893 Department of Agriculture study of 220 stomachs found poultry in just 3 and small rodents making up at least 65% of its food.²⁴ At Hawk Mountain, Pennsylvania, hunters shot hundreds of passing hawks for sport until Rosalie Edge leased the mountain in 1934 and stopped it; the sanctuary she founded was the world's first refuge for birds of prey.²⁵

In the United States the Red-shouldered Hawk is protected under the Migratory Bird Treaty Act: unless federal regulations allow it, it is unlawful to pursue, hunt, take, capture, kill or possess one, or any part, nest or egg of one.^{26, 27} Hawks have been protected under the Act since 1972, the year the 1936 US-Mexico migratory bird convention was amended.²⁸

In Canada, where about 1% of the population breeds, hawks are not covered by the federal Migratory Birds Convention Act; they may be protected under provincial law.^{29, 30} COSEWIC, the national assessment committee, designated the Red-shouldered Hawk Special Concern in 1983 and assessed it Not at Risk in 2006. It is still printed on Schedule 3 of the Species at Risk Act, not on Schedule 1, so the Act's prohibitions do not apply to it.^{30, 31}