The colorful American Kestrel, also known as the Sparrow Hawk, killy hawk, or windhover, is the smallest and most common North American falcon. Its range extends from Alaska and Canada southward through the Americas to Tierra del Fuego. Some are migratory, but some pairs will remain and defend a wintering territory. Kestrels withdraw from their northern most breeding range in the winter. The American Kestrel is closely related to the European Kestrel. If you see a small falcon that appears to be hovering on rapid wing beats over a field or an interstate median, this is most likely the bird. The male Kestrel is a beautiful bird, a fact not usually appreciated when the birds is seen as a dark silhouette against a bright sky. The long, slender, pointed wings are blue-gray, and the back and tail are rufous red. A broad, black band extends across the terminal end of the tail, and a white band extends across the tip of the tail.
Common Kestrels measure 32–39 cm (13–15 in) from head to tail, with a wingspan of 65–82 cm (26–32 in). Females are noticeably larger, with the adult male weighing 136-252 g (c,5-9 oz), around 155 g (around 5.5 oz) on average; the adult female weighs 154-314 g (about 5.5-11 oz), around 184 g (around 6.5 oz) on average. They are thus small compared with other birds of prey, but larger than most songbirds. Like the other Falco species, they have long wings as well as a distinctive long tail.
Their plumage is mainly light chestnut brown with blackish spots on the upperside and buff with narrow blackish streaks on the underside; the remiges are also blackish. Unlike most raptors, they display sexual colour dimorphism with the male having less black spots and streaks, as well as a blue-grey cap and tail. The tail is brown with black bars in females, and has a black tip with a narrow white rim in both sexes. All Common Kestrels have a prominent black malar stripe like their closest relatives.
The cere feet, and a narrow ring around the eye are bright yellow; the toenails, bill and iris are dark. Juveniles look like adult females, but the underside streaks are wider; the yellow of their bare parts is paler. Hatchlings are covered in white down feathers, changing to a buff-grey second down coat before they grow their first true plumage.
Their plumage is mainly light chestnut brown with blackish spots on the upperside and buff with narrow blackish streaks on the underside; the remiges are also blackish. Unlike most raptors, they display sexual colour dimorphism with the male having less black spots and streaks, as well as a blue-grey cap and tail. The tail is brown with black bars in females, and has a black tip with a narrow white rim in both sexes. All Common Kestrels have a prominent black malar stripe like their closest relatives.
The cere feet, and a narrow ring around the eye are bright yellow; the toenails, bill and iris are dark. Juveniles look like adult females, but the underside streaks are wider; the yellow of their bare parts is paler. Hatchlings are covered in white down feathers, changing to a buff-grey second down coat before they grow their first true plumage.
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