Habitat
In the United States, White-tailed Hawks live year-round in southern Texas’s grasslands, prairies, savannas, and pastures. These habitats have some trees and shrubs, primarily scattered mesquite, yucca, and granjeno (spiny hackberry). During prairie fires, White-tailed Hawks (particularly immatures) appear in numbers to hunt rodents and other vertebrates fleeing the flames. These hawks are seldom found in agricultural fields unless there is a fire.
Back to topFood
White-tailed Hawks eat mostly mammals, as well as other small vertebrates and large insects. They hunt from the air and from perches, watching the ground and low vegetation. They are often seen kiting (hanging in the breeze with little flapping) or hovering, often high in the sky, occasionally taking flying insects on the wing. When prey is spotted, they drop quickly onto it, seizing it with the talons. White-tailed Hawks occasionally steal prey from smaller species such as Swainson’s Hawk. Prey include pocket gophers, cotton rats, wood rats, mice, shrews, and rabbits, as well as birds such as King Rail, Northern Bobwhite, Mourning Dove, Eastern Meadowlark, Attwater’s Prairie-Chicken, Greater Roadrunner, Mallard, and domestic chickens. White-tailed Hawks eat many species of lizards, frogs, and snakes, and they occasionally eat roadkill including rattlesnakes. Among invertebrates, they eat crayfish, blue crabs, centipedes, beetles, crickets, grasshoppers, and other large insects.
Back to topNesting
Nest Placement
Nests are normally placed about 6-10 feet off the ground in shrubs, low trees, or succulents in fairly open areas with relatively little tall vegetation but often near a small water feature such as a pond.
Nest Description
Both sexes help build the nest, beginning in midwinter and lasting more than a month. The nest is a bulky, oval mass of dried branches, twigs, grasses, and forbs. Nest dimensions vary widely, averaging roughly 5 inches high, 21 x 9 inches in length and width, and with cup depth about 3 inches.
Nesting Facts
Clutch Size: | 2-3 eggs |
Number of Broods: | 1 brood |
Egg Length: | 2.1-2.6 in (5.27-6.5 cm) |
Egg Width: | 1.7-2.0 in (4.22-5 cm) |
Incubation Period: | 29-32 days |
Nestling Period: | 47-53 days |
Condition at Hatching: | Helpless and covered in down. |
Behavior
White-tailed Hawks form long-term, monogamous pair bonds that often last for multiple nesting seasons. When courting, males, females, and pairs sometimes leave a perch, making a low flight, then rise up to a greater height and return to the perch. In some cases, these flights are directed at an intruder (another hawk or caracara), but in about half the cases, no intruder is present. Copulation often follows such flights. During flights away from the nest, males often settle on the ground and tug on grass or other low vegetation, apparently a courtship display. White-tailed Hawks chase other raptors away from their nests, but they are sometimes displaced by Great Horned Owls, which may usurp newly constructed nests. Both parents tend the young hawks through fledging, but parents expel them from the territory in mid- or late winter. Young birds sometimes gather around areas with plenty of prey or around prairie fires. Most pairs nest from late winter through spring, but egg laying as late as early August has been recorded in Texas, probably a replacement clutch.
Back to topConservation
Fewer than 10,000 White-tailed Hawks live in the continental U.S., but Partners in Flight estimates a global breeding population at 2 million birds and rates them 10 out of 20 on the Continental Concern Score, indicating a species of low conservation concern. White-tailed Hawks are sensitive to nest disturbance, but their greatest challenge is loss of habitat from overgrazing, cultivation, and development. In the tropics, deforestation probably increases habitat available to this species.
Back to topCredits
Crossley, R., J. Liguori, and B. Sullivan. (2013). The Crossley ID Guide: Raptors. Princeton University Press, New Jersery, USA.
Farquhar, C. Craig. (2009). White-tailed Hawk (Geranoaetus albicaudatus), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.
Lutmerding, J. A. and A. S. Love. (2020). Longevity records of North American birds. Version 2020. Patuxent Wildlife Research Center, Bird Banding Laboratory 2020.
Partners in Flight. (2020). Avian Conservation Assessment Database, version 2020.
Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.