The American kestrel (Falco sparverius) is the smallest and most common falcon in North America. It has a roughly two-to-one range in size over subspecies and sex, varying in size from about the weight of a blue jay to a mourning dove. It also ranges to South America, and is a well-established species that has evolved seventeen subspecies adapted to different environments and habitats throughout the Americas. It exhibits sexual dimorphism in size (females being moderately larger) and plumage, although both sexes have a rufous back with noticeable barring. Its plumage is colorful and attractive, and juveniles are similar in plumage to adults.
The American kestrel usually hunts in energy-conserving fashion by perching and scanning the ground for prey to ambush, though it also hunts from the air. It sometimes hovers in the air with rapid wing beats while homing in on prey. Its diet typically consists of grasshoppers and other insects, lizards, mice, and small birds (e.g. sparrows). This broad diet has contributed to its wide success as a species. It nests in cavities in trees, cliffs, buildings, and other structures. The female lays three to seven eggs, which both sexes help to incubate.