There are 320 species of diurnal raptors worldwide (that includes hawks, eagles, kites, falcons, harriers and osprey). 71 of those are just eagle species!
There are 200 species of owl worldwide.
A breakdown of families and orders:
There are three main orders:
1a) Hawks and relations (Accipitridae in the order Accipitriformes)
1b) Ospreys (Panionidae, also in the order Accipitriformes)
2) Secretary Birds (Sagittaridae,alone in the order Sagittariiformes)
3) Falcons and relations (Falconidae in the order Falconiformes)
(New World vultures were considered in the order Falconiformes, but some authorities place them in Ciconiiformes (storks and herons) and might be considered a subfamily of the stork family. Still others feel they should be in an independent order of Cathartiformes, not closely associated with either storks or birds of prey. Confused? That's okay. The experts can't agree on it either.
The owls (Strigiformes) can be divided into two families:
1) Barn Owls and relations (Tytonidae)
2) Typical or other owls (Strigidae)
Smallest birds of prey:
Elf owl (1 1/2 ounces, 5 inches long)
Largest birds of prey:
American Harpy Eagle (up to 20 pounds, 6 1/2 foot wingspan)
Random neat facts:
Pound for pound, an eagle's wing is stronger than an airplane's.
The word "raptor" comes from the Latin word raptare, which means to "seize and carry away".
It is against the law to possess even one raptor feather without a permit from the U.S. government. The 1940 Bald Eagle Protection Act and the 1972 Migratory Bird Treaty Act both make it illegal to possess living or dead native birds (or their nests, eggs or parts) without heavy fines or imprisonment.
Eagle talons can strike with twice the force of a bullet.
Fossils of falcons dating back to 50-million years have been found in Germany.
Osprey have a polarized lens over their eyes enabling them to see under water.
(RAPTOR's American kestrel)
American kestrels are able to see in the ultraviolet range and can follow the urine trail of their prey.
Merlins mimic the flight of pigeons to sneak up on unsuspecting prey.
(RAPTOR's red morph screech owl)
And sometimes, a bird of prey can have a bad feather day.