Hawks

Hawks (family Accipitridae) are one of the major groups of predatory birds that are active during the day. They are members of the order Falconiformes, which also includes the falcons, vultures, and osprey, and like the other Falconiformes, they have the characteristic sharp, strong claws and hooked beak suited for catching and tearing up prey.

Found on all continents but Antarctica, hawks are a diverse group. There are 26 species in North America alone that have been breeding successfully in recent times. They include four species of eagles, five species of kites, and 17 species called hawks. These North American hawks vary from the small, 3-8 oz (85-227 g) sharp-shinned hawk, with a wingspan of about 2 ft (0.6 m), to the ferruginous hawk (Buteo regalis), with a wingspan of 4.5 ft (1.5 m). Eagles are different primarily because of their huge size; they may weigh from 8-20 lb (4-9 kg), with wingspans up to 8 ft (2.4 m).

Besides the hooked beak and strong claws already described, the hawks share several characteristics. Their wings are generally broad and rounded, well-suited for flying over land (kites' wings are different, more like a falcon). Their nostrils are oval or slit-like, and open in the soft skin, the cere, where the upper mandible joins the head, which is round. The neck is short and strong. The large eyes are usually yellow, orange, red, or brown, and turn little in their sockets. Hawks move their heads to direct their vision, which is both monocular and binocular (especially when hunting).

Hawks' plumage is subdued, usually mottled browns and grays on the back and lighter, often barred or streaked, below. Color phases have been found in many species: albinos in 10 species, melanism (a black phase) in five, and erythrism (a red phase) in one.

The North American hawks fall into four groups: the buteos, the accipiters, the kites, and the harriers.