Prairie Falcon (Falco mexicanus)

[order] FALCONIFORMES | [family] Falconidae | [latin] Falco mexicanus | [authority] Schlegel, 1850 | [UK] Prairie Falcon | [FR] Faucon des prairies | [DE] Prariefalke | [ES] Halcon Mejicano | [NL] Prairie-valk

Subspecies

Genus

Physical charateristics

Like a sandy Peregrine, with a white eyebrow stripe and a narrower mustache. In flight overhead this bird shows blackish patches in the wingpits.

Listen to the sound of Prairie Falcon

[audio:http://www.planetofbirds.com/MASTER/FALCONIFORMES/Falconidae/sounds/Prairie Falcon.mp3]

Copyright remark: Most sounds derived from xeno-canto

Range

North America, Middle America : West. The Prairie Falcon can be found in the arid plains and steppes of interior North America, wherever cliffs or bluffs are present for nesting sites, from central British Columbia, northern Alberta and Saskatchewan and western North Dakota, south to Baja California, Mexico and to southern Arizona and New Mexico and northern Texas. Many individuals migrate to Mexico in winter, but numerous adults winter as far north as Alberta.

Habitat

It can be seen perched on telephone poles or cliffs, even sometimes on a wire. In high wind conditions it will alight on a hummock. It shows a prefersnce for treeless areas, up to 12,000 feet, descending from the mountains in colder weather. Open hills, plains, prairies, deserts. Typically found in fairly dry open country, including grassland and desert. Also in open country above treeline in high mountains. In winter, often found in farmland and around lakes and reservoirs, and may regularly winter in some western cities. Avoids forest, and usually scarce on the immediate coast.

Reproduction

Returning singly from their winter quarters, the birds pair on arrival in the breeding grounds. Spectacular courtship dives in full cry by the male have been observed during late February and early March. He also struts about on cliff ledges. Nests are always on cliffs, usually on a ledge with some overhang, but sometimes in a pothole or a larger cave. Either a slight scrape is made for the eggs, or they are laid in an old nest of another bird. Three to six eggs are laid, the clutch being completed by late April. Incubation, mostly by the female, takes 29-31 days. The young hatch over a period of two to three days, with quite sparse down. The wing and tail quills emerge at about two weeks, and at about 30 days they can walk about the ledge. They leave the nest when about 40 days old. The female begins to hunt soon after the young hatch, and the male continues to do so. The favourite foods are ground squirrels and medium-sized birds, but some pairs specialise on larger birds. Sometimes the young are fed with ground squirrels when small, and with birds when larger, and occasionally lizards become a staple.

Feeding habits

Mostly small birds and mammals. Often will focus on one abundant prey species at a time. May feed on ground squirrels in early summer, shifting to young songbirds when many are fledging; in winter, may feed on flocking birds like Horned Lark. Many other species eaten, up to size of grouse and jackrabbits; also lizards, insects.
Uses a wide variety of hunting techniques. Often hunts by flying fast and low over ground, taking prey by surprise. Also will dive steeply from the air or pursue birds in flight. The Prairie Falcon is an excitable bird that harries larger and slower hawks and eagles unmercifully, especially if they appear anywhere near its eyrie. Its usual method of hunting is to fly along at a moderate pitch, up to about 300 feet, and descend in a long slanting stoop on any potential prey. Like other falcons of this group it sometimes feeds extensively on small rodents such as young rabbits or ground squirrels. It is capable, however, of catching in flight even the most rapid birds, and those that are nearly as large as itself.

Video Prairie Falcon

httpv://www.youtube.com/watch?v=A0DdxQDQD-4

copyright: Don DesJardin

Conservation

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be increasing, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size may be moderately small to large, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Migration

Variable: disperses widely with general North to South movement from N breeding locations; movements in all directions from mid-latitude breeding locations; some sedentary tendency in South, but in general follows food supplies; some movements in response to aestivation, and hence inaccessibility, of ground squirrels; most birds breeding at altitudes above 2500 m move to lower ground in winter. Post-breeding vagrants wander outside breeding range more commonly in mid-continent plains region than elsewhere.

Distribution map