American Kestrel; Falco sparverius
A cavity nester, American Kestrels will use holes in trees, rock cavities and crevices in cliffs, artificial nest boxes, or small spaces in buildings. The number of suitable breeding cavities limits this species' breeding density. The American Kestrel has adapted well to nest boxes. In one program, nest boxes were fixed to the backs of signs along a freeway thus allowing kestrels to breed in areas formerly devoid of nest sites. Pairs nesting in boxes on poles have much higher nesting success than pairs using boxes on trees. No nest is built inside. In nest boxes sawdust and wood shavings may be a suitable substrate for the eggs
Both sexes take turns incubating their eggs, a very rare situation among North American birds of prey where the female usually incubates exclusively. Both sexes develop bare oval patches on each side of their breasts where the warm bare skin can contact the eggs for warming. Eggs hatch about 30 days after being laid. There are from three to seven eggs laid, but four to six are average. The eggs are typically short elliptical in shape, and are white or pinkish-white with an even covering of fine spots and flecks of brown shades, occasionally concentrating as a ring or a cap. They will renest if the first nest fails and have been reported to raise 2 broods per year in some of the southern states.