Red-tailed hawk

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Red-tailed Hawk
Scientific classification
Kingdom:
Animalia
Phylum:
Chordata
Class:
Aves
Order:
Falconiformes
Family:
Accipitridae
Genus:
Buteo
Species:
B. jamaicensis
Binomial name
Buteo jamaicensis

The Red-tailed Hawk (Buteo jamaicensis) is a medium-sized bird of prey, one of three species colloquially known in the United States as the "chickenhawk." It breeds almost throughout North America from western Alaska and northern Canada to as far south as Panama and the West Indies, and is one of the most common buteos in North America. There are fourteen recognized subspecies, which vary in appearance and range.

It is one of the largest members of the genus Buteo in North America, weighing from 690 to 2000 grams (1.5 to 4.4 pounds) and measuring 45–65 cm (18 to 26 in) in length, with a wingspan from 110 to 145 cm (43 to 57 in). The Red-tailed Hawk displays sexual dimorphism in size, as females are 25% larger than males. Red-tailed Hawk plumage can be variable, depending on the subspecies. These color variations are called morphs, and a Red-tailed Hawk may be light, dark, or rufous.

The Red-tailed Hawk is successful in large part because it tolerates a wide range of habitats and altitudes, including deserts, grasslands, coniferous and deciduous forests, tropical rainforests, agricultural fields and urban areas. It lives throughout the North American continent, except in areas of unbroken forest or the high arctic.It is also legally protected in Canada, Mexico and the U.S. by the Migratory Bird Treaty Act of 1918.

The Red-tailed Hawk is a popular bird in falconry, particularly in North America. Approximately 60% of all raptors under 1 year of age taken from the wild for use in American falconry are Red-tailed Hawks. The Red-tailed Hawk also has significance in Native American culture. Its feathers are considered sacred by some tribes, and are used in religious ceremonies.

Description

Rufous morph

A male Red-tailed Hawk may weigh from 690 to 1300 grams (1.5 to 2.9 pounds) and measure 45–56 cm (18 to 22 in), while a female can weigh between 900 and 2000 grams (2 and 4.4 pounds) and measure 50–65 cm (20 to 26 in) in length. As is the case with many raptors the Red-tailed Hawk displays sexual dimorphism in size, as females are 25% larger than males. The wingspan is from 110 to 145 cm (43 to 57 in).[2]

Red-tailed Hawk plumage can be variable, depending on the subspecies and the region. These color variations are morphs, and are not related to molting. The western North American population, B. j. calurus, is the most variable subspecies and has three color morphs: light, dark, and intermediate or rufous. The dark and intermediate morphs constitute 10–20% of the population.[3]

Though the markings and hue vary, the basic appearance of the Red-tailed Hawk is consistent. The underbelly is lighter than the back and a dark brown band across the belly, formed by vertical streaks in feather patterning, is present in most color variations. The red tail, which gives this species its name, is uniformly brick-red above and pink below.[4] The bill is short and dark, in the hooked shape characteristic of raptors.[4] The cere, the legs, and the feet of the Red-tailed Hawk are all yellow.[2]

Immature birds can be readily identified at close range by their yellowish irises. As the bird attains full maturity over the course of 3–4 years, the iris slowly darkens into a reddish-brown hue. In both the light and dark morphs, the tail of the immature Red-tailed Hawk are patterned with with numerous darker bars.[4]

Taxonomy

The Red-Tailed Hawk is a member of the genus Buteo, a group of medium-sized raptors with robust bodies and broad wings. Members of this genus are known as buzzards in Europe, but hawks in North America.[5]

There are at least 14 recognized subspecies of Buteo jamaicensis, which vary in range and in coloration:

  • B. j. jamaicensis, the nominate subspecies, occurs in the northern West Indies, including Jamaica, Hispaniola, Puerto Rico and the Lesser Antilles but not the Bahamas or Cuba. El Yunque National Forest, Puerto Rico holds the highest known density of Red-tailed Hawks anywhere. [1]
  • B. j. alascensis breeds (probably resident) from southeastern coastal Alaska to the Queen Charlotte Islands and Vancouver Island in British Columbia.[6]
  • B. j. borealis breeds from southeast Canada and Maine south through eastern Texas west to northern Florida. It winters from southern Ontario east to southern Maine and south to the Gulf coast and Florida.[6]
  • B. j. calurus breeds from central interior Alaska, through western Canada south to Baja California. It winters from southwestern British Columbia southwest to Guatemala and northern Nicaragua.[6] Paler individuals of northern Mexico may lack the dark wing marking.[7]
  • B. j. costaricensis is resident from Nicaragua to Panama. This subspecies is dark brown above with cinnamon flanks, wing linings and sides, and some birds have rufous underparts. The chest is much less heavily streaked than in northern migrants (B. j. calurus) to Central America.
  • B. j. fuertesi breeds from northern Chihuahua to southern Texas. It winters in Arizona, New Mexico, and southern Louisiana.[6] The belly is unstreaked or only lightly streaked, and the tail is pale.
  • B. j. fumosus Islas Marías, Mexico
  • B. j. hadropus Mexican Highlands
  • B. j. harlani usually has blackish plumage contrasting with white undersides of the flight feathers; the tail may be reddish or gray and is longitudinally streaked rather than barred. The dark wing marking is not distinct. It breeds in Alaska and northwestern Canada and winters from Nebraska and Kansas to Texas and northern Louisiana.[6]
  • B. j. kemsiesi is a dark subspecies resident from Chiapas to Nicaragua. The dark wing marking may not be distinct in paler birds.[7]
  • B. j. kriderii is paler than other Red-tails, especially on the head; the tail may be pinkish or white. In the breeding season, it occurs from southern Alberta, southern Saskatchewan, southern Manitoba, and extreme western Ontario south to south-central Montana, Wyoming, western Nebraska, and western Minnesota. In winter, it occurs from South Dakota and southern Minnesota south to Arizona, New Mexico, Texas and Louisiana.[6]
  • B. j. socorroensis Socorro Island, Mexico
  • B. j. solitudinus Bahamas and Cuba
  • B. j. umbrinus occurs year-round in peninsular Florida north to Tampa Bay and the Kissimmee Prairie.[6] It is similar in appearance to calurus

The four island forms, jamaicensis, solitudinus, socorroensis, and fumosus, do not overlap in range with any other subspecies.

Distribution and habitat

The Red-tailed Hawk is one of the most widely distributed hawks in North America. It breeds from central Alaska, the Yukon, and the Northwest Territories east to southern Quebec and the Maritime Provinces, and south to Florida, the West Indies, and Central America. The winter range stretches from southern Canada south throughout the remainder of the breeding range.[6]

Its preferred habitat is mixed forest and field, with high bluffs or trees that may be used as perch sites. It tolerates a wide range of habitats and altitudes, including deserts, grasslands, coniferous and deciduous woodlands, tropical rainforests, agricultural fields and urban areas.[1] It is second only to the Peregrine Falcon in tolerance of diverse habitats in North America.[8] It lives throughout the North American continent, except in areas of unbroken forest or the high arctic.[3]

The Red-tailed Hawk is widespread,[8] partially due to historic settlement patterns across North America, which have benefitted it. The clearing of forests in the Northeast created hunting areas, while the preservation of woodlots left nest sites. The planting of trees in the west allowed the Red-tailed Hawk to expand its range by creating nest sites where there had been none. The construction of highways with utility poles alongside treeless medians provided perfect habitat for perch-hunting. The Red-tailed Hawk can also be found in cities.[9] The non-fiction book Red-Tails in Love: A Wildlife Drama in Central Park, by Marie Winn, which made Pale Male, a Red-tailed Hawk in New York, the most famous urban Red-tailed Hawk.[10]

Behavior

Red-tailed Hawk screaming

In flight, this hawk soars with wings in a slight dihedral, flapping as little as possible to conserve their needed energy. Active flight is slow and ponderous with deep wing beats. It sometimes hovers on beating wings and sometimes "kites", or remains stationary above the ground by soaring into the wind.[3] When soaring or flapping its wings, it typically travels from 20 to 40 mph, but when diving may reach speeds as high as 120 mph.[11] When the Red-tailed Hawk walks on the ground, its steps are slow and awkward. It only walks while feeding on carrion. While chasing insects or snakes at ground level, it hops in energetic, erratic patterns.[3]

The Red-tailed Hawk is generally non-aggressive toward people and toward other birds. It is commonly attacked by crows, magpies, owls, other hawks, and even songbirds over territorial disputes, though it is generally not injured. When threatened by an intruder, a Red-tailed Hawk will generally flee rather than defend its nest.[12]

The cry of the Red-tailed Hawk is a two to three second hoarse, rasping scream, described as kree-eee-ar,[9] which begins at a high pitch and slurs downward [11] This cry is often described as sounding similar to a steam whistle.[2] It frequently vocalizes while hunting or soaring, but vocalizes loudest in annoyance or anger, in response to an predator or a rival hawk's intrusion into its territory.[9] At close range, it makes a croaking "guh-runk".[12] Young hawks may utter a wailing klee-uk food cry when parents leave the nest. [13]

Diet

Juvenile eating a vole

The Red-tailed Hawk is carnivorous, and an opportunistic feeder. Its diet is mainly composed of small mammals, birds and reptiles. Prey varies with regional and seasonal availability, but usually includes cottontails, rodents, pheasants and quail.[13] It may also prey on waterfowl, bats, shrews, snakes, lizards, crustaceans, insects, and when near the waters edge, carp and catfish.[11][14]The Red-tailed Hawk hunts primarily from an elevated perch sites. It will swoop down from a perch to seize prey, catching birds while flying, or pursuing prey on the ground from a low flight.[14]

Prey taken can range in size from beetles to White-tailed Jackrabbits, which are double the weight of most Red-tails. In captivity in winter, an average redtail will eat about 135 g (4-5 oz) daily.[13] The Great Horned Owl occupies a similar ecological niche nocturnally, taking similar prey. Competition may occur between the Red-tailed Hawk and the Great Horned Owl during twilight.

Reproduction

Parent in nest with chicks.

The Red-tailed Hawk reaches sexual maturity at three years of age. It is monogamous, mating with the same individual for many years.In general, the Red-tailed Hawk will only take a new mate when its original mate dies.[14] The same nesting territory is defended by the pair for years. During courtship, the male and female fly in wide circles while uttering shrill cries. The male performs aerial displays, diving steeply, then climbing again. After repeating this display several times, he approaches the female from above, and grasps her talons briefly with his own. Courtship flights last 10 minutes or more. Once the flight is completed, mating takes place. The male and female spiral to the ground, then 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.[15]

Once the pair has mated, they build a stick nest in a large tree 4 to 21 m off the ground or on a cliff ledge 35 m (115 ft) or higher above the ground, or may nest on man-made structures. The nest is generally 71 to 97 cm (28 to 38 inches) in diameter and can be up to 90 cm (3 feet) tall. The nest is constructed of twigs, and lined with bark, pine needles, corn cobs, husks, stalks, aspen catkins, or other plant matter. Fresh plant matter is deposited into the nest throughout the breeding season to keep the nest clean. and defending the same nesting territory. Great Horned Owls compete with the Red-tailed Hawk 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.[2]

A clutch of 1 to 5 eggs is laid at the beginning of April, with eggs laid approximately every other day. The egg shells are a bluish-white with occasional brown splotches and have a granulated or smooth matte surface. The eggs are usually about 60 x 47 mm (2.4 x 1.9 in). and defending the same nesting territory. They are incubated by both the male and female. The male may spend less time incubating than the female, but brings food to the female while she incubates. After 28 to 35 days, the eggs hatch over 2 to 4 days; the nestlings are altricial at hatching. The female broods them while the male provides most of the food to the female and the chicks. The female feeds the nestlings after tearing the food into small pieces. After 42 to 46 days, the chicks begin to leave the nest on short flights. The fledging period lasts up to 10 weeks, during which the young learn to fly and to hunt.[2]

Relationship with humans

The Red-tailed Hawk has a complex relationship with humans. It is capable of both controlling rodents and other mammalian pests. The name "chickenhawk" was applied to the Red-tailed Hawk in the belief that it regularly killed chickens and other domestic fowl. In reality, this is a rare occurence, though farmers may sometimes shoot Red-tailed Hawks, mistakenly believing that this species is a great threat to their fowl.[12] Throughout their range in Canada, Mexico and the U.S., the Red-tailed Hawk receives special legal protections under the Migratory Bird Treaty Act of 1918.[16]

Use in falconry

The Red-tailed Hawk is a popular bird in falconry, particularly in America where the sport of falconry is highly regulated at the federal and state levels. According to the United States Fish and Wildlife Service, approximately 60% of all raptors taken from the wild (specifically birds under 1 year of age which are not breeding adults) for use in American falconry are Red-tailed Hawks. Most falconers eventually release their wild-caught raptors back into the wild once they are of breeding age.There are less than 4,000 falconers in the United States, therefore any effect on the Red-tailed Hawk population, estimated to be approximately one million in the United States, is statistically insignificant.[16]

Behaviorally, the Red-tailed Hawk is generally an easy bird to keep and use in the field. It will, however, revert to a semi-wild state in 1–3 weeks without training or hunting, which makes it straightforward to fatten the bird, then return it to the wild once the hunting season is over and the breeding season is beginning. This technique is commonly used by nature centers in the Red-tailed Hawk's native locations.[17]

Light morph Red-Tailed Hawk, hunting.

The Red-tailed Hawk is a powerful and sturdy falconry bird best flown at larger ground quarry such as squirrels, rabbits, and jackrabbits. However, small males are generally not flown at squirrels, as squirrel bites can cause serious or permanent damage to a male's smaller feet and toes.[18] Though accipiters such as the Goshawk, Cooper's Hawk, or Sharp-shinned Hawk, are generally used to catch winged quarry, the Red-tailed Hawk may take the occasional pigeon, crow, duck, and even Prairie Chicken using cooperative hunting techniques. The falconer positions the bird for a fast and stealthy approach while flushing the game, in order to maximize the Red-tailed Hawk's chances of success.[18]

A falconer hunting with a Red-tailed Hawk most commonly turns the hawk loose and allows it to perch in a tree or other high vantage point. The falconer, who may be aided by a dog if the bird accepts dogs as hunting partners, then attempts to flush prey by stirring up ground cover. A well-trained Red-tailed Hawk will follow the falconer and dog, realizing that their activities produce opportunities to catch game. Contrary to popular belief, once a raptor catches game, it does not bring it back to the falconer. Instead, the falconer must locate the bird, make in, and trade the bird its kill in exchange for a piece of ready-to-eat meat, which is generally from a previous kill.[17]

Feathers and Native American use

The feathers and other parts of the Red-tailed Hawk are considered sacred to many American indigenous people and, like the feathers of the Bald Eagle and Golden Eagle, are sometimes used in religious ceremonies and found adorning the regalia of many Native Americans in the United States; these parts, most especially their distinctive tail feathers, are a popular item in the Native American community.[19] As with the other two species, the feathers and parts of the Red-tailed Hawk are regulated by the eagle feather law[20], which governs the possession of feathers and parts of migratory birds.[21]

Gallery

References

  1. ^ a b "Buteo jamaicensis". {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help); Unknown parameter |assessors= ignored (help) Cite error: The named reference "IUCN" was defined multiple times with different content (see the help page).
  2. ^ a b c d e Dewey, T. and D. Arnold. "Buteo jamaicensis". {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  3. ^ a b c d "Red-tailed Hawk". Bureau of Land Management. Retrieved June 6. {{cite web}}: Check date values in: |accessdate= (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  4. ^ a b c "Buteo jamaicensis". U.S. Geological Survey. {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  5. ^ "Buteo jamaicensis". ITIS. Retrieved June 10. {{cite web}}: Check date values in: |accessdate= (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  6. ^ a b c d e f g h Tesky, Julie L. "Buteo jamaicensis". U.S. Department of Agriculture. Retrieved June 10. {{cite web}}: Check date values in: |accessdate= (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  7. ^ a b Howell, Steve N. G.;Sophie Webb (1994). A Guide to the Birds of Mexico and Northern Central America. Oxford University Press. ISBN 0-19-854012-4.{{cite book}}: CS1 maint: multiple names: authors list (link)
  8. ^ a b Garrigues, Jeff. "Biogeography of Red-tailed hawk". San Francisco State University Department of Geography. {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  9. ^ a b c "Red-tailed Hawk". Sky-hunters.org. {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  10. ^ Geist, Bill. "In Love With A Hawk". CBS. {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  11. ^ a b c Day, Leslie. "The City Naturalist - Red Tailed Hawk". 79th Street Boat Basin Flora and Fauna Society. {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  12. ^ a b c "Red-Tailed Hawk". Oregon Zoo. {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  13. ^ a b c "Red-tailed Hawk - Buteo jamaicensis". The Hawk Conservancy Trust. {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  14. ^ a b c Terres, John K. (1980). The Audubon Society Encyclopedia of North American Birds. New York, NY: Knopf. p. 1109. ISBN 0394466519.
  15. ^ "Buteo jamaicensis". Oiseaux.net. {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  16. ^ a b "Migratory Bird Treaty Act of 1918". U.S. Fish and Wildlife Service. {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help) Cite error: The named reference "Federal Register" was defined multiple times with different content (see the help page).
  17. ^ a b McGranaghan, Liam J. (2001). The Red-Tailed Hawk: A Complete Guide to Training and Hunting North America's Most Versatile Game Hawk. Western Sporting Publications. p. 181. ISBN 0-9709571-0-6.
  18. ^ a b Mullinex, Matthew (2002). American Kestrels in Modern Falconry. Ranchester, Wyoming: Western Sporting Publications. p. 142. ISBN 1-888357-05-3.
  19. ^ Collier, Julie. "The Sacred Messengers". Mashantucket Pequot Museum. {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  20. ^ "TITLE 50--Wildlife and Fisheries". Electronic Code of Federal Regulations (e-CFR). {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  21. ^ Cook, Stephen. "Feather Law". Mashantucket Pequot Museum. {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)

See also

  • Pale Male - A Red-tailed Hawk that nests on a building along New York's Central Park.

External links

Wikimedia Commons has media related to Buteo jamaicensis.
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