The prairie falcon (Falco mexicanus) is a medium-sized, light-brown falcon that breeds in wide-open, semiarid and prairie habitats in the western United States, southwestern Canada, and northern Mexico. Prairie falcons generally breed in the vicinity of cliffs or canyons and hunt over nearby, open terrain, and sometimes on open forests. The prairie falcon is migratory, wintering in the southern parts of its breeding range, as far south as central Mexico.
The prairie falcon is a crow-sized bird, with a typical body length of 17 in (43 cm). It has narrow, pointed wings, a square tail, a hooked, predatory beak, and strong, raptorial feet and claws.
Like other falcons, the prairie falcon is a strong, fast flier. The usual prey of this bird is small birds and mammals. The prairie falcon also has spectacular nuptial displays similar to other falcons, which involve the male bird (or tiercel) making fast-flying stoops from great heights as well as other aerial acrobatics. These are all designed to impress the female with his potential prowess as a hunter.
The nest is usually located on a ledge, on a cliff, or sometimes in an abandoned tree-nest of another large bird, such as a crow or hawk. The prairie falcon lays three to six eggs, which are mostly incubated by the female, which is fed by the male as she broods. Both of the parents care for the young birds.
Prairie falcons have declined somewhat in abundance as a result of losses of habitat to agriculture and the effects of toxic insecticides. However, while they are important, their population decreases have not been as great as those of some other raptors, especially the peregrine falcon (Falco peregrinus), which was much harder hit by chlorinated insecticides.
The present prairie falcon population appears to be stable. However, some populations have declined in Utah, western Canada, and agricultural parts of California. Eggshell thinning and mercury poisoning (due to this falcon's preying on the seed-eating horned lark) has been reported, which may be contributing to this species declining numbers.
Ehrlich, Paul R., David S. Dobkin, and Darryl Wheye. The Birder's Handbook. New York: Simon & Schuster Inc., 1988.
Sibley, David Allen. The Sibley Guide to Birds. New York: Knopf, 2000.