Red-tailed hawks are native only to the Nearctic region. They are found throughout the United States and Canada, and into Mexico and Central America. Many birds are year round occupants although the birds of the far north migrate south during the fall to escape the harsh winter.
Red-tailed hawks inhabit a wide range of habitats over a wide range of altitudes. These habitats are typically open areas with scattered, elevated perches, and include scrub desert, plains and montane grasslands, agricultural fields, pastures, urban parks, patchy coniferous and deciduous woodlands, and tropical rainforests. Red-tailed hawks prefer to build their nests at the edge of forests, in wooded fence rows, or in large trees surrounded by open areas. (Preston and Beane, 1993)
Red-tailed hawks are 48 to 65 centimeters in length. Their wingspan is approximately 4 feet, or 122 centimeters. Females and males are similar in appearance, but females are 25% larger than males. This kind of sexual dimorphism, where females are larger than males, is common in birds of prey. Mass is reported from 795 to 1224 grams, with mass varying by sex, season, and geographically. Red-tailed hawks range from light auburn to deep brown in color. Their underbelly is lighter than the rest of the body, with a dark band across it. The cere (the soft skin at the base of the beak), the legs and the feet are all yellow. The tail is brownish-red, and it is this trait that gives red-tailed hawks their name.
Immature red-tailed hawks look similar to adults, but... Immatures also have yellowish-gray eyes that become dark brown as adults.
There are at least 14 subspecies of (Preston and Beane, 1993). These subspecies are separated based differences in their color and differences in where they breed and spend the winter.
Red-tailed hawks usually begin breeding when they are three years old. They are monogamous, and mate with the same individual for many years. In fact, red-tailed hawks usually only change mates when their original mate dies. During courtship, the male and female soar together in circles, with flights lasting 10 minutes or more. Mating usually takes place following these flights. The male and female land on a perch and preen each other. The female then tilts forward, allowing the male to mount her. Copulation lasts 5 to 10 seconds. (Preston and Beane, 1993)
Red-tailed hawk nests are usually 28 to 38 inches in diameter. They are sometimes used for several years, and can be up to 3 feet tall. The male and female both construct the nest in a tall tree, 4 to 21 meters above the ground. Where trees are scarce, they are sometimes built on cliff ledges or artificial structures such as on buildings. The nests are constructed of twigs and lined with bark, pine needles, corn cobs, husks, stalks, aspen catkins and other soft plant matter. Fresh bark, twigs, and pine needles are deposited into the nest throughout the breeding season to keep the nest clean. Owls compete with the red-tailed hawks for nest sites. Each species is known to kill the young and destroy the eggs of the other in an attempt at taking a nest site.
The female lays 1 to 5 eggs around the first week of April. The eggs are laid approximately every other day and are incubated for 28 to 35 days. Both parents incubate the eggs. Males may spend less time incubating than females, but bring food to the female while she is on the nest. The young hatch over the course of 2 to 4 days, and are altricial at hatching. During the nestling stage, the female broods the young, and the male provides most of the food to the female and the chicks. The female feeds the nestlings by tearing the food into small pieces. The chicks begin to leave the nest after 42 to 46 days. The fledgling period lasts up to 10 weeks, during which the chicks learn to fly and hunt. (Preston and Beane, 1993)
Both parents incubate the eggs. Males may spend less time incubating than females, but bring food to the female while she is on the nest. The newly hatched chicks are altricial (helpless). During the nestling stage, the female broods the young, and the male provides most of the food to the female and the chicks. The female feeds the nestlings by tearing the food into small pieces. The chicks begin to leave the nest after 42 to 46 days. After they leave the nest, young red-tailed hawks usually stay in one place, close to their parents. They begin to fly about 3 weeks after they first begin to leave the nest, and begin to catch their own food 6 to 7 weeks after that. They become completely independent from their parents by about 10 weeks after fledging, at about 112 to 116 days old. (Preston and Beane, 1993)
Red-tailed hawks are relatively long-lived birds. While many of these birds die young (most live less than two years), those that survive the first few years can live for many years. The oldest known wild red-tailed hawk lived to at least 21.5 years old. In captivity, red-tailed hawks have lived for at least 29.5 years. (Preston and Beane, 1993)
Red-tailed hawk pairs remain together for years in the same territory. These birds are very territorial, and defend territories that range in size from 0.85 to 3.9 square kilometers, depending on the amount of food, perches, and nest sites in the territory. The female is usually the more aggressive partner around the nest itself, whereas the male more aggressively defends the territory boundaries. The birds will soar over their territory, mostly on clear days, looking for intruders. Red-tailed hawks are diurnal (active during the day). (Preston and Beane, 1993)
Home range sizes range from 1.3 to 5.2 square kilometers. The size of red-tailed hawk home ranges varies with the quality of habitat, the sex of the individual, and the season. (Preston and Beane, 1993)
Adult red-tailed hawks make what is called a horse scream, "kee-eeee-arrr." It is often described as sounding like a steam whistle. The length and pitch of this call varies with the age, gender, and geographic region of the individual red-tailed hawk.
Young red-tailed hawks communicate with their parents by making soft, low "peep"-ing sounds. As they get older, they sounds they make deepen in tone, and are usually sounds of hunger.
Red-tailed hawks also communicate through body language. In an aggressive posture, the body and head of the red-tailed hawk are held upright and its feathers are standing up. In submission, the hawk's head is lower to the ground and the feathers are smooth. Red-tailed hawks also display many aerial behaviors. In the talon-drop, during courtship, they swoop down trying to touch one another with their talons. Undulating-flight is an up and down movement that is mainly used in territorial display. Finally, in the dive-display the bird performs a steep dive. This is also a territorial display.
Red-tailed hawks have extraordinarily keen vision, which allows them to detect prey movements at great distances.
Red-tailed hawks feed on a wide variety of prey, using their powerful claws as weapons. Eighty to eighty-five percent of their diet consists of small rodents. Mammals as large as eastern cottontail rabbits may also taken. Reptiles and other birds make up the rest of the diet. Male red-winged blackbirds are common prey because they are so visible when guarding their nests. Red-tailed hawks do most of their hunting from a perch. They are not known to store food. (Preston and Beane, 1993)
Adult red-tailed hawks are large formidable birds, and have few predators. Most predation on this species occurs to eggs and nestlings. Great horned owls are known predators of red-tailed hawk nestlings. Corvids are known predators of eggs and nestlings. (Preston and Beane, 1993)
Red-tailed hawks play an important role in local ecosystems by helping to control the populations of small mammals, including rodents and rabbits. They also provide habitat for some small bird species, including house sparrows, that live in active red-tailed hawk nests.
Red-tailed hawks have antagonistic relationships with many bird species. Some smaller bird species mob hawks. Red-tailed hawks also steal prey and have prey stolen by other large birds, including golden eagles, bald eagles and ferruginous hawks. (Preston and Beane, 1993)
Red-tailed hawks help farmers by eating mice, moles and other rodents that disturb their crops.
There are no known negative effects of red-tailed hawks on humans.
Red-tailed hawks have extended their geographic range over the last 100 years. This expansion is most likely the result of increasing habitat of patchy woodland and open areas. As these areas become filled in with forest or more completely opened up, the amount of habitat for red-tailed hawks is expected to decline.
Currently, the greatest threats to red-tailed hawk populations are shootings, collisions with automobiles, and human interference with nesting activities. Lead poisoning from eating food items that contain lead shot also kills a number of red-tailed hawks each year.
Red-tailed hawks are protected under the U.S. Migratory Bird Act and CITES Appendix II. (Preston and Beane, 1993)
Albinism is relatively common in red-tailed hawks.
Red-tailed hawks are considered to be a sign of good luck in the Mescalero Apache tradition (Louie Chavez, personal communication).
Tanya Dewey (author), Animal Diversity Web, Kari Kirschbaum (editor), Animal Diversity Web.
Delena Arnold (author), University of Michigan-Ann Arbor.
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
uses sound to communicate
living in landscapes dominated by human agriculture.
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
Referring to an animal that lives in trees; tree-climbing.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
an animal that mainly eats meat
uses smells or other chemicals to communicate
in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
union of egg and spermatozoan
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
makes seasonal movements between breeding and wintering grounds
Having one mate at a time.
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
"many forms." A species is polymorphic if its individuals can be divided into two or more easily recognized groups, based on structure, color, or other similar characteristics. The term only applies when the distinct groups can be found in the same area; graded or clinal variation throughout the range of a species (e.g. a north-to-south decrease in size) is not polymorphism. Polymorphic characteristics may be inherited because the differences have a genetic basis, or they may be the result of environmental influences. We do not consider sexual differences (i.e. sexual dimorphism), seasonal changes (e.g. change in fur color), or age-related changes to be polymorphic. Polymorphism in a local population can be an adaptation to prevent density-dependent predation, where predators preferentially prey on the most common morph.
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).
scrub forests develop in areas that experience dry seasons.
breeding is confined to a particular season
reproduction that includes combining the genetic contribution of two individuals, a male and a female
living in residential areas on the outskirts of large cities or towns.
uses touch to communicate
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
Living on the ground.
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
living in cities and large towns, landscapes dominated by human structures and activity.
uses sight to communicate
Brett, James. 1986. The Mountain and the Migration: A Guide to Hawk Mountain. Cornell Press, Ithaca.
Brewer, Richard; Gail Mcpeek, Raymond Adams Jr. 1991. The Atlas of Breeding Birds of Michigan. Michigan State University, East Lansing.
Elphick, Johnathan. 1995. the Atlas of Bird Migration. Random House, New York.
Johnsgard, Paul. 1990. Hawks, Eagles, And Falcons of North America. Smithsonian Institution Press, Washington.
Newton, Ian. 1990. Birds of Prey. Facts on File, New York.
Scholz, Floyd. 1993. Birds of Prey. Stack Pole Boods, Pennsylvania.
Stokes, David and Lillian. 1989. A Guide to Bird Behavior Vol.III. Little Brown and Company, New York.
Preston, C., R. Beane. 1993. Red-tailed hawk (Buteo jamaicensis). Pp. 1-24 in A Poole, F Gill, eds. The Birds of North America, Vol. 52. Washington DC and Philadelphia, PA: The Academy of Natural Sciences and The American Ornithologists' Union.