What is a raptor?
Adaptations of Raptors
Raptor Body Shapes
Taxonomy of Raptors
What is a bird?
Birds are vertebrates with feathers, modified for flight and for active metabolism. There are a few kinds of birds that don't fly, but their ancestors did, and these birds have secondarily lost their ability to fly. Modern birds have developed the following traits:
What is a raptor?
A raptor, also known as a bird of prey, is a type of bird often characterized by a strong, curved (or hooked) beak, strong, sharp talons, and keen eyesight.
The word “Raptor” is derived from the Latin word raptor meaning plunderer (from the verb to snatch or seize.) There are almost 500 species of raptors worldwide all sharing some common traits, or adaptations that help them to survive. Raptors are often known as hunters of the sky.
Male and female raptors are sexually dimorphic, females are larger and males and also have similar coloration. And they look alike.
Adaptations of Raptors
Raptors are predators. Like all predators, they hunt and kill other animals for food so their diet consists primarily of meat.
Raptors have keen eyesight.
Most rely heavily on sight to locate their food so they have developed large extremely sensitive eyes. In the entire bird world, birds of prey have extremely keen eyesight, enabling them to spot potential prey from a very long distance. In fact, an eagle can see a rabbit from almost a mile away!
Their eyes are fixed in their head, meaning they can’t roll their eyes from side to side like we can. So in order to see what is going on around them they must constantly move their head to survey their surroundings. Just watch a bird for a couple of minutes and you will see it almost constantly moving its head, looking around.
To help in its ability to survey its surroundings, raptors (as well as most other birds) have more neck (or cervical) vertebrae than humans. Birds have a highly flexible neck, consisting of 13 to 25 vertebrae.
Owls have an added advantage over other raptors because of their sharp night vision. Their eyes are even larger than those of other raptors and their pupils can open very wide to let in a tremendous amount of light. The pupils can also close to a pinpoint, giving them excellent eyesight during the daytime as well. Owls can see in dim light at least 35x better than humans and perhaps 100x better.
Raptors have a keen sense of hearing.
Raptors make a broad range of noises and use their voice and hearing as a means of communication. They also rely on their hearing heavily for locating their prey, combined with their sharp vision. Some raptors use their hearing more than others do. Owls use their hearing quite often to assist in finding prey at night.
Raptors have a strong, hooked beak.
Stout, thick, and sharply hooked, raptor beaks are a highly specialized tool. Each bird of prey’s beak is slightly modified because of its specific dietary needs. For example, falcons have a tooth (called a tomial tooth) that is designed to lock onto and sever the neck bones of smaller birds. The soft, fleshy part of the bill (located at the top of the bill) is called the cere and this is where the nostrils are located. Beaks are made of keratin (just like human hair and fingernails). Bird beaks grow continuously (like our hair and nails) and it is constantly shedding and flaking off, maintaining a sharp edge capable of tearing flesh apart.
Raptors have talons.
A talon is the claw of a bird of prey, its primary hunting tool. The talons of raptors are lethal weapons, perfectly designed for catching, holding, and carrying prey. Most birds of prey have 3 toes pointing forward and 1 pointing backward. These toes can exert an extremely powerful grip upon their catch and can literally crush it to death. Talons are the first line of defense for raptors and they are used to capture their prey.
Males vs. Female Raptors
Most female birds of prey are larger and heavier than the males. This is called reverse sexual dimorphism. Also, male and female raptors have similar coloration making it difficult to distinguish between the genders.
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Raptor Body Shapes
Raptors come in many shapes and sizes. New Jersey is home to over 20 different types of raptors, each having its own unique shape and size that can help to identify it. When identifying a bird of prey in flight, look mainly at the body shape, size, and how it flies.
There are 3 general types of raptors: buteos, accipiters, and falcons.
Buteos are soaring hawks having long broad wings and wide fanned tails. They are built to glide on air currents, soaring for long stretches without flapping their wings. They will hunt from perches such as trees or utility poles and wait for unsuspecting prey to move below. Buteos that live or migrate to New Jersey include the red-tailed hawk, broad-winged hawk, red-shouldered hawk, and rough-legged hawk.
Accipiters have short, round wings, and long rudder-like tails. They typically live in the forest so their short wings and long tails enable them to maneuver quickly through the trees. They dart through trees chasing their favorite prey, other birds, on the wing. Although they sometimes soar like buteos, their typical flying style is several flaps followed by a glide. (Think “flap – flap – soar” when you see an accipiter flying over head.) Cooper’s hawks, goshawks, and sharp-shinned hawks are all accipiters living in New Jersey.
Falcons are the fastest birds of prey. They are built for speed with streamlined bodies and long, pointed wings. Falcons most often flap continuously in flight. Falcons living or migrating to New Jersey include the peregrine falcon, American kestrel, and merlin. The American kestrel, the smallest falcon, is able to hover in one place while hunting small rodents and insects. The peregrine falcon is the world’s fastest animal, capable of flying at speeds of over 200 miles an hour in pursuit of prey. This behavior is known as a stoop.
Other birds of prey living or migrating to New Jersey include eagles, osprey, Northern harrier, vultures, and owls.
Eagles are the largest birds of prey found in North America. There are 2 species – the bald eagle and the golden eagle. The bald eagle is our national symbol. Their wingspans can reach 8 feet in length. Bald eagles are similar to buteos but they are much larger, with longer, narrower wings. The bald eagle is a fish eater (though it can eat other prey) so it is seldom far from water. The golden eagle is associated with wilderness and mountainous habitats, and they feed on a variety of mammals. Bald eagles are year-round residents in New Jersey (over 60 pairs in 2008) while Golden eagles typically are found during their migration and occasionally in the winter months.
Osprey have very long narrow wings that are often bent at the wrist so that their wings from an “M” shape. From below, ospreys have contrasting dark and light plumage. They tend to glide extensively. Often called fish hawks, osprey hunt mainly fish and are seldom far from water. When hunting, osprey plunge feet first into the water to capture fish swimming near the surface. Osprey have rough pads on their feet with little spines on them to help them grab and hold onto slippery fish.
Northern harriers hold their wings above their body, resembling a “V” shape. The feathers on their face are stiff to help transit sound. These feathers create a pronounced “facial disk” similar to an owl face. Unlike other hawks, the Northern harrier relies on it hearing as well as its vision to capture prey. Northern harriers can be identified by a white rump patch at the base of their long narrow tails. Males and females look somewhat different. The male is white below with a light gray back and hood,(sometimes called “the grey ghost”); the female is mottled in browns.
Vultures also hold their wings in a “V” or a dihedral. They are easily identified by their rocking flight as they soar in circles. Unlike most birds or prey, vultures have a keen sense of smell, which helps them to find their favorite food, dead and rotting animals. In New Jersey, there are 2 types of vultures: turkey vultures and black vultures. Turkey vultures are large dark brown birds with silvery white along the length of its wings. Black vultures are smaller than turkey vultures with a shorter tail and white patches just at the tip of its wings. Black vultures hold their wings flatter than a turkey vulture and flap its wings more frequently.
Owls are birds of prey that hunt and feed at night. They have extremely good eyesight and highly sensitive hearing. Some species of owl can hunt by hearing alone. Their huge eyes are fixed in their skulls (like most birds of prey); to look from side to side they must rotate their head. Some species of owls can rotate their head over 270 degrees! Owls also have silent flight – their flight feathers are serrated that act as a muffler reducing the sound of air moving over the feathers. There are 8 species of owls that visit New Jersey sometime during the year or live in New Jersey year-round. Owls that breed in New Jersey include the great-horned owl, screech owl, barn owl, barred owl, long-eared owl and sometimes the short-eared owl. Migrant species in New Jersey or species infrequently seen include the saw-whet owl and snowy owl.
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Taxonomy of Raptors
Taxonomy is the practice and science of classification. Carolus Linnaeus was a Swedish scientist who developed the classification system in use today. It categorizes organisms into a hierarchy of kingdoms, phylums, classes, orders, families, genera, and species based on shared physical characteristics. As you move down the ranks (from Kingdom down to Species), the organisms become more closely related. Groups at the top of the hierarchy (kingdom, phylum, class) contain a greater number of organisms than the more specific groups that are lower in the hierarchy (families, genera, species). By assigning each group of organisms to a kingdom, phylum, class, order, family, genus, and species, they can be uniquely characterized. Their membership in a group tells us about the traits they share with other members of the group.
Every known living organism on Earth is classified and named by a set of rules. Those rules are used by all scientists around the world. The names are called scientific names, not common names. Common names may vary from place to place. For example, a mountain lion may also be called a puma or a cougar depending on the geographic area that it is found. Scientific names follow a specific set of rules. Scientists use a two-name system called binomial nomenclature. Scientists name all organisms using the genus and species of the organism. The first word is the genus and the second word is the species. The first word is capitalized and the second word is not. So a mountain lion’s scientific name is Puma (the genus) concolor (the species).
Let us classify the peregrine falcon as an example:
Kingdom Animalia (peregrine falcons are animals)
Phylum Chordata (they have a spinal cord and are also vertebrates)
Class Aves (they are birds)
Order Falconiformes (they are diurnal, or daytime, birds of prey)
Family Falconidae (they are falcons)
Genus Falco (falcon)
Species peregrinus (peregrine)
Raptors belong to 2 scientific orders Strigiformes (OWLS) and Falconiformes (DIURNAL BIRDS OF PREY).
These 2 Orders are divided into 6 Families.
Order: FALCONIFORMES: approx. 285 species in 4 familiies
Family Accipitridae approximately 230 species:
Vultures (7 species)
Hawks and Eagles (226 species)
Family Falconidae approximately 64 species:
Falcons
Family Pandionidae 1 species:
Osprey
Family Sagittariidae 1 species in Africa:
Secretary Bird
Order: STRIGIFORMES: approx. 148 species in 2 families
Family Strigidae approximately 129 species
Typical owls such as the great horned, screech and snowy owls.
Family Tytonidae approx. 19 species:
Barn owls
Masked owls and relatives
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