Sagittariidae - There is only one species in this family, the secretary bird (Sagittarius serpentarius). Though classified as a Falconiformes, it has many crane-like physical qualities, such as long legs and short, blunt toes. The secretary bird lives in the savannas of sub-Saharan Africa.
Pandionidae - There is also only one species in this family, the osprey (Pandion haliaetus). This fish-eating species can be found near coasts, lakes and rivers worldwide. It has a unique foot structure. The outer front toe can swing to face backward with the hind toe, an adaptation for grasping their prey.
Cathartidae - New World vultures. There are 7 species in the family and they are found in open country and forests from southern Canada to southernmost South America. Like Old World vultures, they're primarily carrion eaters and have more or less unfeathered heads. Unlike Old World vultures, they don't have a syrinx (voice box), don't build nests, and their septum (the structure that separates the two nostrils) is perforated. The Andean (Vultur gryphus) and California condors (Gymnogyps californianus), turkey vulture (Cathartes aura), and black vulture (Coragyps atratus) are in this family.
Falconidae - Falcons and caracaras. The family Falconidae contains 60 species and can be found worldwide except Antarctica. Falconidae are generally agile predators relying more on live prey than carrion. They are similar to birds in the family Accipitridae, but their beaks are notched, and they have proportionately longer wings. The peregrine falcon (Falco peregrinus), prairie falcon (Ffalco mexicanus), and American kestrel (Falco sparverius) are in this family.
Accipitridae - Hawks, eagles, kites, Old World vultures, harriers, and buzzards. The family Accipitridae contains 217 species. The members of this varied group are believed to be derived from a common kite-like ancestor. Most are active predators and build stick nests. Bald eagles (Haliaeetus leucocephalus), red-tailed hawks (Buteo jamaicensis), Cooper's hawks (Accipiter cooperii), and golden eagles (Aquila chrysaetos) are in this family.
Genus and species - The Order Falconiformes has 286 species worldwide. There are 31 species that are generally considered North American birds.