Mean annual count: 3, Lowest annual count year : 1, Highest one-day count: 1, on 24 Oct. Field marks: Chunky, light-colored, broad-winged buteo, with dark patagial marks on undersides of its wings.
Generally brown above and whitish below. Some individuals have darkish belly bands. Adults have rufous tails; juveniles have barred, brownish tails. The Red-tailed Hawk is characterized by variability and versatility.
Redtails are numerous migrants at many watchsites throughout their North America range. The fact that they tend to perch and soar in open habitats and tolerate human-dominated environments makes them one of the most frequently observed raptors in the region.
The reddish or rufous tail of adults makes the species one of the most easily recognized raptors. Red-tailed Hawks have adapted to human landscapes with isolated trees or small woodlots that provide nest sites and elevated perches for hunting, and their numbers have increased in North America in recent years. Human actions that have benefited the Red-tailed Hawk in the eastern United States include forest thinning and the construction of the Interstate Highway System, both of which have created prime hunting areas.
In the American West, fire suppression and power lines provide additional perches for hunting. Red-tailed Hawks also have benefited from protection from human persecution. It has a chunky body, broad wings, and a tail that is often spread or fanned in flight. The species varies in plumage across its range.
Distinct differences exist between age groups, and among color morphs, and races. Individual redtails range from brown to black on their upperparts, and white to black underneath. The tail, which can be solid rufous, or is banded brown, is sometimes streaked or spotted. Adults typically have a reddish or rufous tail with a narrow, dark band at the tip. Compared with adults, juveniles have narrower wings and longer tails that are brownish with seven to nine dark brown bands of equal width.
Dark morphs, which are common in the American West, are rare in the eastern United States. Adult light morphs have a dark brown head, back, and upperwing coverts. The underparts are pale cream or whitish with dark markings that often form a belly band. The underwings are pale with dark, rectangular patagial marks. During the breeding season, soaring flight plays a major role in helping individuals establish and maintain nesting territories.
When soaring, redtails can survey their territory and locate intruders. Migrants begin their aerial courtship displays in late winter and early spring. Sedentary birds which remain paired throughout the year engage in aerial displays throughout the year although most displays take place in early spring.
During such breeding displays, pairs soar together in wide circles at high altitudes, and males often engage in steep dives and subsequent ascents. Males typically fly above and slightly behind the female, and sometimes the two interlock talons and spiral toward the ground.
Pairs either build a new nest or refurbish an old nest. Nests are constructed of two to three foot long branches that are usually less than half an inch thick. Both the male and female take part in nest building. When building their nests, redtails are secretive, and if disturbed, may abandon the site. Nest sites vary depending on available habitat, but in general they are open from above, and have a good view of the surrounding landscape.
In forested areas, redtails usually choose to nest close to the trunk or near the tops of trees. Some individuals nest on cliffs and human constructions such as powerline towers. Redtails lay a total of one to five eggs with roughly hour intervals between eggs. The incubation period is 28 to 35 day begins shortly after the first egg is laid. The female does most of the incubation, and during this period the male feeds her. After the eggs hatch, the female broods the nestlings for 30 to 35 days, and the male continues to provide most of the food.
Swainson's Hawk Latin: Buteo swainsoni. White-tailed Hawk Latin: Geranoaetus albicaudatus. These birds need your help.
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Spread the word. Stay abreast of Audubon Our email newsletter shares the latest programs and initiatives. Widespread and common. Apparently has increased in some areas since the s, and numbers now stable or still increasing. In several regions of North America, Red-tailed Hawks are adapting to nesting in cities. Open country, woodlands, prairie groves, mountains, plains, roadsides. Found in any kind of terrain that provides both some open ground for hunting and some high perches.
Habitats may include everything from woodland with scattered clearings to open grassland or desert with a few trees or utility poles. Some sites hire professional counters to cover each season. Some areas maintain exciting public education programs and hold migration festivals, all of which depend on enthusiastic volunteers. People watch hawks because it is fun and exciting. Still, recording numbers of migrating and reporting them into an extensive international database lets us document migration and help determine population trends.
While data from one site is of limited use, data from across the continent over the years is one of the best means of assessing the health of raptor populations. Conducting counts and supporting HMANA are ways anyone who loves raptors can help make a difference in their future. HMANA also provides scientifically-reasoned opinions on issues of importance to raptors to government at all levels.
Hawk migration is an incredibly complex phenomenon. Unlike many songbirds, most hawks migrate exclusively during daylight hours, offering people one of the best opportunities to see them migrating. Quoting liberally from James J. But en route, migrants may encounter topographic features in the form of coasts or mountain ridges that concentrate and direct the birds; biologists call these barriers leading lines.
Some species, including some raptors, readily fly across large lakes or bays, even open ocean. But for the most part, birds of prey tend to migrate over land, where mountain ridges serve as important leading lines. The air currents associated with mountain ridges allow migrating hawks to conserve energy during flight, and hawks will follow these ridges as long as they point in the general direction of migration. Not all hawks migrate.
Some primarily southern species do not. Many species are partial migrants, with northern populations migrating relatively short distances within North America and southern populations remaining sedentary. Some migratory species now live year-round in many cities. While most fall migrations occur in September and October, a few raptors migrate south already in July or as late as January.
Spring migration is more minor because of the perils of the long migrations and wintering deaths, especially for birds hatched the previous summer. Spring migration primarily in April and May but can begin in January and end in June. The fall migration includes the young hawks that fled that year, so more birds are migrating than in the spring.
Some spring sites along the south shores of the Great Lakes have exceptional flights where you can see some of the most significant hawk flights in the US and southern Canada. However, in most other areas, spring hawk watches are notably fewer than in the fall, and spring flights are far smaller.
Some species leave their northern breeding grounds and make long migrations into Central and South America. These include the Broad-winged Hawk, one of our most abundant raptors; the Osprey, one of our most iconic raptors; and the Rough-legged Hawk. Other species have even more complex strategies, such as the Peregrine Falcon, some of which migrate thousands of miles to southern South America. In contrast, others Peregrines migrate much shorter distances or do not migrate at all.
Some Peregrines and several other species, such as Osprey, might migrate long distances over the open ocean. Broad-winged and Red-tailed Hawks generally avoid flying long distances over water because they rely primarily on a thermal lift to help reduce their energy expenditure.
Thermals are created by columns of warm air rising from the heated earth when the surrounding air mass is cooler. These thermals allow birds to soar high with little effort.
Reflecting the complexity of migration, each gender or age class in a species usually migrates at a slightly different time than other classes of the same species.
In Sharp-shinned Hawks, juveniles tend to migrate first, often push up against the coasts as they search for prey and migration routes, and avoid flying over water. Mature sharp shins tend to migrate a little later than the young of the year, and they have a much better idea of where they are relocating to, so their routes are typically shorter and more direct. Thus you might well see more sharpies predominantly juveniles at Cape May along the southern Jersey shore and primarily adult birds in the smaller sharpie flight at Hawk Mountain, inland on a mountain ridge.
In the east, juvenile Ospreys tend to make long southbound flights over the open ocean in the middle of hurricane season, a risky proposition. Their more conservative elders tend to fly along or over the East Coast landmass where they can sit down for the night, feed readily, and wait out storms, crossing water only when necessary in the Caribbean.
If you are looking for Rough-legged Hawks, they migrate south primarily in October-December, and winter primarily in the southern Canadian provinces and the northern US, and are much less abundant than the Broad-winged or Red-tailed Hawk. Because of the elevations and colder temperatures involved, raptors in western North America tend to migrate a bit earlier than in the east.
Migration is always a challenge, whether to survive hurricanes, poor weather, snow, cold, and lack of prey. Adult birds will migrate to the same wintering area where they wintered the year before. Many juvenile hawks migrate on their own and need to find a wintering area, or they wander over large territories, looking for adequate prey, compatriots, better weather, etc.
Because Larger adult females and smaller adult males often elect to winter in slightly different habitats and focus on other prey. Spring migration is generally quicker as adult birds are pressed to return to their breeding grounds, build a nest, and find their previous or a new mate. Many juveniles do not breed in their second calendar year, so they tend to migrate back a bit later than the adults and might not return to their natal area. Anyone interested in migration is always learning something new, so it is exciting to talk with other hawk watchers and read counts and reports from elsewhere.
A guide to the birds of Mexico and northern Central America. Oxford University Press, New York. Jenkins, M. Red-tailed Hawk Buteo jamaicensis. In Oklahoma Breeding Bird Atlas, pp. Reinking, ed. University of Oklahoma Press, Norman. Lockwood, M. The TOS handbook of Texas birds. Patrikeev, M. Texas Ornithol. Preston, C. In Colorado Breeding Bird Atlas, pp. Kingery, ed. Poole and F. Gill, eds.
The Birds of North America, Inc.
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