What is a Raptor?
Information retrieved from the
Birder's Handbook, Ehrlich, Dobkin, and Wheye.

A raptor is a bird of prey. They are hawks, eagles, owls, and falcons, but more importantly, they are a vital link in the food chain. Raptors are very different from passerines and they have several characteristics that make them unique.

Hunting
Raptors exhibit a variety of hunting techniques. Aside from owls, all are diurnal hunters meaning they spend most of their time finding food during the day. Whether snatching songbirds, hovering above mice in the field, or soaring, raptors are extremely talented at what they do. Raptors can scan surrounding terrain with telescopic vision. Imagine being able to see a mouse wiggle its nose from 100 yards away! Most prey die a quick death, with razor sharp talons being driven into their bodies. Those that don't die quickly, are killed by one quick bite from the beak. However, none of these hunting techniques could be accomplished without the specialized body parts of the raptors.

Vision
Most birds have "binocular" vision. The birds of prey have developed vision that must estimate ever-changing distances to moving prey. The eyes are rotated toward the front of the head so the visual fields overlap. The eyes of the owls are almost as overlapping as the human eye. Raptors also have the ability to pick up very tiny objects. They have a high visual acuity--the capacity to make fine discriminations. The structure of a hawk's eye is very unique in that each eye functions like a telescope. The lens is flattened and placed farther from the retina, giving it a long "focal length" which produces a large image.

Feet
Raptors have toes highly separated like human fingers. Their toes are very strong with sharp talons, and roughened pads on the undersides of the toes help grasp their prey.

Wings
The wings of an owl are very unique. The leading primary has a serrated edge (like a saw) that disrupts the flow of air. This enables them to be the silent stalkers of the night. When a wing is broken or injured, owls have a hard time sneaking up on their prey, and hunting gets harder. Raptors are also good judges of wind speed. In order to hover, a raptor must beat its wings at the same speed as the air current.

Migration
Every year, during spring and fall, thousands of birds take wing on windy days to head to their breeding grounds or to their wintering grounds. This spectacle, called migration is stressful and requires a lot of energy. In an effort to conserve energy, raptors will use thermals, warm pockets of rising air, so they can spend a minimal amount of energy flapping and most of the trip soaring. Many of the raptors that breed in Nebraska are migratory, including Swainson's hawks, peregrine falcons, bald eagles, and Mississippi kites.

Large flocks of raptors are called "kettles" and you will often see kettles in Nebraska comprising 20 birds or more. One of the most common kettling species in Nebraska is the Swainson's hawk, which you see in harvested crop fields jumping around eating grasshoppers, which are bountiful in the fall. Not all raptors form kettles though. Often you will see individual birds, like the sharp-shinned hawk, zigging and zagging through your backyard looking for small birds, or peregrine falcons swooping for ducks at wetlands.

With so many raptors passing through Nebraska during spring and fall, it is the perfect time to count their populations. Nature centers, like the Hitchcock Nature Center, spend as many as six to eight hours a day observing and counting migrating raptors. This information provides valuable data about the status of many migrator raptors. Click here to find more information about 1999's raptor totals.

Migration is a stressful time of year. Some birds cannot find adequate food, or may be exhausted from their long journey. For RRN, this is an especially busy time of year. Birds migrate to escape cold weather, to find adequate habitat to raise young, and to find food sources available during limited times of the year.