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By Tanya Dewey
Geographic Range
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.
Habitat
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)
These animals are found in the following types of habitat:
temperate 
; tropical ; terrestrial .
Terrestrial Biomes:
desert or dune ; savanna or grassland ; forest ; rainforest ; scrub forest .
Other:
urban ; suburban ; agricultural ; riparian .
Physical Description
(24.29 to 51.39 oz; avg. 37.84 oz)
(17.72 to 25.59 in)
(48.03 in)
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. 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 Buteo jamaicensis. These subspecies are separated based differences in their color and differences in where they breed and spend the winter. (Preston and Beane, 1993)
Some key physical features:
endothermic ; bilateral symmetry ; polymorphic .
Sexual dimorphism: female larger.
Reproduction
Red-tailed hawks breed each spring.
Breeding occurs in the spring.
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)
Mating systems:
monogamous .
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)
Key reproductive features:
iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; oviparous .
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)
Parental investment:
altricial ; pre-fertilization (provisioning, protecting: female); pre-hatching/birth (provisioning: female, protecting: male, female); pre-weaning/fledging (provisioning: male, female, protecting: male, female); pre-independence (provisioning: male, female, protecting: male, female).
Lifespan/Longevity
[External Source: Max Planck Institute for Demographic Research]
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)
Behavior
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
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)
Key behaviors:
arboreal ; flies; diurnal ; motile ; migratory ; territorial .
Communication and Perception
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.
Food Habits
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)
Primary Diet:
carnivore (eats terrestrial vertebrates).
Animal Foods:
birds; mammals; reptiles.
Predation
- great horned owls (Bubo virginianus)
- crows (Corvus)
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)
Ecosystem Roles
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)
Key ways these animals impact their ecosystem:
creates habitat.
Economic Importance for Humans: Negative
There are no known negative effects of red-tailed hawks on humans.
Economic Importance for Humans: Positive
Red-tailed hawks help farmers by eating mice, moles and other rodents that disturb their crops.
Ways that people benefit from these animals:
controls pest population.
Conservation Status
IUCN Red List: [link]:
Least Concern.
US Migratory Bird Act: [link]:
Protected.
US Federal List: [link]:
No special status.
CITES: [link]:
Appendix II.
State of Michigan List: [link]:
No special status.
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)
Other Comments
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).
For More Information
Find Buteo jamaicensis information at
Contributors
Tanya Dewey (author), Animal Diversity Web, University of Michigan Museum of Zoology.
Kari Kirschbaum (editor), Animal Diversity Web Staff.
Delena Arnold (author), University of Michigan.
