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Red-shouldered Hawks are a rather discreet denizen of woodland habitats, rarely particularly visible but often betraying their presence with loud vocalizations. They are a member of the Buteo genus, a group of about 30 species found almost worldwide, only excluding Australasia and far south-east Asia. These are typically medium-sized, stocky raptors with broad wings for extensive soaring. Red-shouldered Hawks are medium-small and slender buteos and spend more time under forest cover than other family members. They are less likely to be seen soaring.
There are five subspecies of Red-shouldered Hawk, all with quite similar appearances
- B.l.lineatus of southeast Canada and eastern USA
- B.l.texanus of southeast Texas
- B.l. alleni of southeast USA
- B.l.extimus of south Florida
- B.l.elegans of southwest Oregon, west California, and Baja California
Taxonomy at a Glance
- Kingdom: Animalia
- Phylum: Chordata
- Class: Aves
- Order: Accipitriformes
- Family: Accipitiridae
- Genus: Buteo
- Species: Buteo lineatus
How to Identify a Red-shouldered Hawk
Red-shouldered Hawks are medium-sized hawks that, at first glance, can appear rather nondescript and difficult to recognize, but there are a few good clues to learn that help with identification. The immediate impression of an adult can be of quite a warm-toned, rather rufous bird, even though the eponymous red shoulders may not be visible.
While there is some individual variation, most individuals have a gray-brown head and back. The upperwing is dark with whitish tips to the feathers, forming an almost checkerboard-like pattern. The underside of the body is barred rufous and white, with the rufous bars being larger and denser on the upper chest, often forming a solid broad rufous breast band. The tail is relatively long compared to other buteo hawks and is dark with several narrow white bands and a fine white tip.
In flight, both the upperwing and underwing show a distinct pale crescent towards the wing tip, at the base of the primaries. This is a really good and visible distinguishing feature and often shows well in photos too. I usually find this to be the clincher for identifying a flying Red-shouldered Hawk. The underwing is distinctly two-toned, with the underwing coverts a pale rufous, usually comparable with the underwing coverts in color. The underside of the flight feathers are neatly barred, dark and white, with dark wing tips. Like most raptors, the legs are yellow, and the beak is dark with a yellow cere.
There is not a huge variation between subspecies, though the birds in the north of the range are slightly larger than southern subspecies, a trait frequently reflected throughout the natural world. This pattern, known as Bergmann’s Rule, allows for northern animals to have a smaller surface area to body volume ratio, reducing heat loss during times of cold weather. The birds in south Florida are most notable in plumage differences, being a little grayer overall with a particularly light gray head.
Juveniles are less richly colored and not so distinctively rufous. They are mostly brown above, with cream underparts which are streaked brown. The pale crescent in the wing is present and visible at all ages.
The most similar and common confusion species are Red-tailed Hawks and Broad-winged Hawks. The pale crescent near the wing tip of Red-shouldered Hawks is a good separating feature, and Red-tailed Hawks are larger and stockier and lack the neatly barred tail. Broad-winged Hawks lack the rufous tones of Red-shouldered Hawks and are rather brown instead.
Where Do Red-shouldered Hawks Live: Habitat
Red-shouldered Hawks are a woodland species and, when nesting, will always be found in areas with at least some trees, though this can vary from dense woodland to sparsely wooded parkland and suburban areas. In winter, they may prefer slightly more open habitats like wetlands and farmland, usually rough, wilder areas where prey is more abundant.
Only the northernmost breeding population of Red-shouldered Hawks migrate annually, those that nest in southeast Canada and the northeastern USA. As prey availability reduces in the fall in these areas, usually in late September and October, they will start to push south. Most are short-distance migrants, traveling 300-1500km into more southeastern USA, but some will go as far as northeast Mexico.
Red-shouldered Hawk Diet and Feeding
Red-shouldered Hawks hunt a wide variety of prey within their woodland habitat. They will perch quietly and still, a few meters above the ground, watching for movement on the forest floor below before dropping directly onto or swooping a short distance to catch their prey.
Favored food items vary depending on habitat and location but mostly include small mammals, particularly voles and chipmunks. In wetter areas, alongside a woodland stream or on the edge of a pond, they will look for frogs and toads and, in some areas, have even been recorded hunting crayfish.
In winter, when usual prey items are less abundant, they will also hunt birds. They lack the necessary speed of more specialist bird hunting hawks, so they will often ambush at feeders. I have seen them hunting tired migrant songbirds that have been concentrated on a shoreline by bad weather in the fall.
Red-shouldered Hawk Breeding and Nesting
The start of Red-shouldered Hawk nesting season varies significantly with geographical range; those in southern areas like Florida and southern California will commence in January. Still, migrants returning to Canada do not start until May.
Courtship and pair bonding can take a week or two and consists of soaring together. The male often engages in ‘sky dancing,’ an impressive display where he dives steeply and rapidly, then quickly regains height to repeat the process, demonstrating his speed, strength, and agility to the potential mate.
They are rather vocal during this period while soaring and during time spent examining and choosing potential nest sites within the forest. After both male and female have constructed the nest (or refurbished the previous year’s home), the female lays three to four pale blue-white eggs with subtle brown blotches. She incubates for the majority of the next month, with the male usually only taking over while she leaves to eat food that he has caught for her.
After another five to six weeks, the young are ready to leave the nest, but they still remain dependent on their parents for food for at least another six weeks.
Red-shouldered Hawk Population
Unlike some raptor species that migrate through concentrated routes, making them easier to count, Red-shouldered Hawks are rather sedentary, with just a small proportion of the population migrating. This complicates population assessments, as locating the species on Breeding Bird Surveys is not always easy in their woodland habitats.
They are also most apparent and thus more easily recorded very early in the breeding season. Their visible and audible courtship is concentrated in a short timeframe before they take a much lower profile once the eggs have been laid. This results in a lower likelihood of being detected during regular survey efforts. It is estimated that there are around one million Red-shouldered Hawks, though this count comes with a certain margin of error.
Are Red-shouldered Hawks Endangered?
Red-shouldered Hawks have an extensive range over large areas of North America, and their population appears to be quite stable over the past century. Thus they are classified as ‘Least Concern’ by IUCN. The few that do migrate have been studied at watchpoints, such as Hawk Mountain, Pennsylvania, since the 1930s, and counts of these birds have been pretty consistent over this time.
However, their population previously declined enormously following deforestation in the 1800s, removing large areas of suitable habitat. They were probably a highly abundant species before this happened. Continuing forest clearance and forest fragmentation remain a threat, as do issues that affect other birds of prey, such as vehicle collision, electrocution on power lines, and accidental or deliberate trapping poisoning in agricultural areas.
Red-shouldered Hawk Predators
As a bird of prey, Red-shouldered Hawks do not get targeted by many other species, but they do not quite sit safely at the top of the food chain. The main threat comes from Great Horned Owls, which will attack roosting and nesting adults during the night. Like many birds, the nesting stage is the most vulnerable during their lifespan; eggs and chicks can be taken by opportunistic predators, including corvids and raccoons.
Red-shouldered Hawk Lifespan
The oldest recorded wild Red-shouldered Hawk reached 26 years of age, which is remarkable for a bird of prey and is likely to be an extreme case. Many Red-shouldered Hawks will die before reaching one or two years old, and most before the age of five. As is the case for many wild animals, learning to find food and stay safe is a challenge in the first few months of life, particularly during the first winter, and many will perish of starvation before the following spring.
FAQs
Answer: Red-shouldered Hawks do indeed have red shoulders, but it is not exactly a prominent feature. When perched, their wings look dark with pale markings, and the red shoulders on the upperwing are usually mostly hidden by the folded wing. Of course, when you see one flying, you are normally looking up at the underside of the bird, so again the red shoulder patches are not visible most of the time.
Answer: If you live in or are visiting the eastern USA or southeast Canada, you stand a good chance of seeing Red-shouldered Hawks. There are not really any particular hotspots where you have a higher likelihood of connecting, but spending time in any woodland habitat is a good tactic. In winter, they often move to slightly more open habitats, so it may be easier to spot them. Reduced foliage cover on trees increases their visibility at this time as well.
Only a small proportion of the population migrates, so large numbers do not pass by watchpoints. Each season a few hundred pass by the hotspot of Hawk Mountain, PA, mostly in late October. I saw a few dozen migrating over Long Point, Ontario, one fall season, and it was always a notable moment in the day as they were quite irregular in their appearance.
Answer: Sometimes, the presence of hawks and birds of prey can be viewed negatively by ill-informed people, who may be worried bout sharing an environment with a predator with sharp talons and a hooked beak. But they really have nothing to worry about; hawks will always try and stay well away from humans. They recognize that even the smallest, youngest child is far too big to be considered a potential prey item.
The only time a hawk may attack a human is if somebody were to threaten its nest containing eggs or chicks. In such a scenario, the hawk would make warning swoops at the intruder, calling loudly but not coming too close. If the threat continues, the hawk may eventually try and strike with its feet, but this is extremely rare and not something that most people need to worry about. Even licensed banders studying a nest site are unlikely to be hurt by a hawk.
Research Citations
- Ferguson-Lees, J.; Christie, D. (2001). Raptors of the World. London: Christopher Helm. ISBN 0-7136-8026-1.
- Dykstra, C. R., J. L. Hays, and S. T. Crocoll (2020). Red-shouldered Hawk (Buteo lineatus), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA.
- del Hoyo, J.; Elliot, A.; Sargatal, eds. (1996). Handbook of the Birds of the World. Vol. 3. Barcelona: Lynx Edicions. ISBN 84-87334-20-2.
- BirdLife International (2022) Species factsheet: Buteo lineatus. Downloaded from http://www.birdlife.org on 27/09/2022
- https://www.hawkmountain.org/raptors/red-shouldered-hawk
- https://www.audubon.org/field-guide/bird/red-shouldered-hawk#