The nest site, known as an aerie, is generally recessed in a cliff face and is basically a scrape in the rubble of the bedrock. No nest is built from sticks or other material but existing rubble may be rearranged. Cliff heights may vary from 25 or more (7.8 meters) feet and the nest location may be anywhere on the face but is often less than 50 feet (15.5 meters) from the bottom of the cliff so long that it is safe from mammalian predators. The scrape is usually under some type of overhang that shelters it from the weather.
Clutch size varies geographically from two to six eggs with an average close to four in most places. The laying interval between each eg is one to two days. The eggs are pinkish-white with fine, regular spots over half of the surface and larger, more irregular spots over the other half. The dots are in the brown, reddish-brown and purplish shades but often, an overlying wash of similar tones may obscure the spots at one end. While slightly paler than other falcons, the Prairie Falcon's eggs give the impression of an overall buff or brownish splotched egg as opposed to white. The eggs are subelliptical and average 2 inches long (5.1 centimeters) by 1.6 inches wide (4.1 centimeters).
The male arrives at the aeries first and will do a some cleaning up of the scrape. It feeds the female from the time egg- laying starts throughout incubation and the close brooding of the downy young. Occasionally, the male will incubate the eggs while the female hunts or feeds on prey he has brought to her. Once the young are hatched, the male continues to feed them. Over the entire nesting period, the male brings about 75 percent of all the prey items to the nest. From the onset of egg-laying, the females spend most of their time incubating or brooding until the young are about two weeks old. Small periods are spent off of the nest for hunting and feeding. Once the young are 12 to 14 days old, the adult female begins to hunt and bring food back to the nest along with the male. Both sexes will defend the nest. Prey items are often cached before being brought to the nest and both sexes engage in this behavior although each uses different cache sites.
The incubation period is 31 days, occasionally longer and begins with the laying of the first egg. As more eggs are laid, the time spent incubating increases so that the first egg does not hatch far ahead of the last egg as in some raptors. The clutch hatches over a period of several days. Around day 30, the young will move toward the edge of the nest in anticipation of flight. Fledging occurs between 36 and 41 days. There is a short post-fledging period of family association before dispersal away from the aerie and family separation. The Prairie Falcon is single-brooded but will replace clutches lost early in the nesting period. This will occur within 15 to 20 days at the same nest or occasionally at a nearby site.
#Which birds of prey use this type of nest?;question\Q31\Q31.wav
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ùôÇÇîÇÇ Cliffs and ledges
ôÇÇîÇÇ #Which birds of prey use this type of nest?;question\Q31\Q31.wav
