According to the Raptor Research Foundation, the most apparent difference between eagles, hawks and falcons is size. Eagles are among the largest birds of prey, while certain species of falcon weigh less than 50 grams. Hawks, a varied group of raptors, usually fall somewhere in the middle. The different sizes and builds of these birds allow them to hunt in unique ways.
The wingspans of common North American eagles, such as the golden eagle and the bald eagle, can reach 7 feet, while the American kestrel, a small species of falcon, has a wingspan of less than 2 feet, according to About.com. Birds in the falcon family have tapered, narrow wings that, combined with their diminutive size, grant them immense speed and agility. This makes them preferred birds for the sport of falconry. Most hawks, on the other hand, have shorter, rounded wings and long tails. These features allow them to soar on air currents without flapping. Most hawks are divided into two categories: accipiters, or forest hawks, and buteos, or grassland hawks. Eagles are identified by their powerful wings and heavy beaks. They also possess the ability to soar on thermals for great lengths of time, and their sharp eyesight is paired with this skill to make them keen hunters. The Raptor Research Foundation states that there are 75 known species of eagle.