Diurnal Birds of Prey: Falconiformes

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DIURNAL BIRDS OF PREY: Falconiformes

PHYSICAL CHARACTERISTICS

The birds in the order Falconiformes are called raptors (RAP-ters), or birds of prey, meaning they hunt animals for food. The raptors in the order Falconiformes include hawks, eagles, Old World vultures (from Africa, Asia, and Europe), falcons, and secretary birds. These raptors hunt during the day, and have beaks and feet that are made for hunting. Their beaks have sharp hooks that can tear meat. Their legs are generally short, and their feet have long, curved claws called talons (TAL-unz) that can grab and kill prey. These raptors have excellent eyesight, and can see about eight times better than humans.

Most of the birds in the Order Falconiformes have compact bodies, rounded heads, and short necks. Their sizes range from tiny falconets that weigh just over a pound (28 grams) to griffon vultures that can weigh as much as 26 pounds (12 kilograms). The secretary bird has the longest legs and stands 4 feet (1.2 meters) tall. Female raptors are usually larger than the males.

Raptors' feathers are mostly gray, brown, or black. Some have tan or white chests, often with brown spots or streaks. These colors help camouflage the birds as they sneak up on prey. Many of them have bristles (stiff feathers) around their beaks that may protect their eyes while feeding or help them feel the prey they have caught. Most raptors have large flight feathers and are excellent fliers.


GEOGRAPHIC RANGE

Falconiformes live on every continent except Antarctica.

HABITAT

Most raptors are land birds, although some of them snatch fish from lakes or oceans. They live in every kind of land habitat, including the tundra of the far north, forests, grasslands, wetlands, deserts, mountains, farmlands, seacoasts, and even large cities.


DIET

Except for vultures, raptors kill the animals they eat. Most raptors are not fussy—they will eat any animal they can catch. These animals include mammals, birds, fish, reptiles, insects, frogs, crabs, and snails. Some also eat eggs and garbage, and vultures eat carrion (dead animals). A few of the birds have special diets and eat only one or two kinds of prey.

Each type of raptor has a special way of hunting. A falcon usually catches its prey on the wing. It grabs the prey in midair with its talons and kills it with a bite to the neck. A small hawk usually sits on a perch and makes short flights to catch a mouse or other prey on the ground. The hawk squeezes it to death with its strong feet. Then it takes the prey to a perch to pluck it before eating it. Larger hawks and eagles hunt by riding high on warm air currents, and they have to wait until the air warms up each morning before flying off.

Some of the birds in the Falconiformes group have unusual ways of hunting. Kestrels are little falcons that hover in open areas, hunting for insects or small mammals. Secretary birds are in a family by themselves, and they are quite different from hawks and falcons. They are big birds with long legs and they usually run after their prey. When they catch it, they kick it to death.


BEHAVIOR AND REPRODUCTION

Raptors have simple calls that are often high-pitched and may sound something like "keer-keer." Pairs often call to each other to say, "I'm here—where are you?" At migration time, huge flocks of raptors journey north and south together. Hawks that breed in northern areas make up the biggest flocks, but some falcons also make long migration trips.

Most raptor pairs live by themselves. They have to protect large territories in order to find enough food. But some of the Old World vultures and smaller falcons nest and feed together. Most falcons make simple nests on the ground, but some hawks and eagles build large nesting platforms that can be several feet high. Usually, the males hunt for food while the females sit on the nest. The chicks of the largest raptors stay in the nest for several months after hatching. Most of the larger raptors raise only one chick a year, and some do not breed every year.


FALCONIFORMES AND PEOPLE

From prehistoric times, birds of prey have been a part of people's lives. Many people admire the birds, and some even worshiped them as part of their religion. But others are afraid of them or think they are bad because they kill other animals. Pictures of raptors are used to symbolize power, freedom, strength, and speed. The bald eagle is the national bird of the United States, and birds of prey appear on flags, coins, and shields in many countries.

Many farmers appreciate the way raptors kill mice and other animals that eat the grain in their fields. But other people blame the birds for killing farm animals, pets, and racing pigeons. Usually the damage done by the birds is not nearly as great as some people think it is. In the United States and many other countries, it is illegal to kill these raptors, but some people do it anyway.

In some parts of the world, people participate in a sport called falconry. Falconers are hunters who train falcons and hawks to catch pheasants, rabbits, and other wild game animals for their trainers. The birds are rewarded with a treat, but they do not eat the animals they kill.

Raptors usually fly long distances by riding on rising bubbles of warm air called thermals. They find the thermals above land, so they do not fly long distances over water. At migration time, bird watchers gather at places such as Panama where the land narrows. Thousands of hawks may pass over the area every hour for weeks.

AT THE TOP

Raptors are the top predators in many habitats. That means that nothing eats them. It may sound like an easy life, but raptors have to be skillful fliers in order to catch a mouse zipping along the ground or a bird flying past them. When a bald eagle spots a fish swimming below, it has to drop through the air at just the right speed and judge where the fish will be when it hits the water. If all goes well, the eagle will lock the slippery fish in its talons and swoop up. But raptors are not always that lucky. The prey animals often get away and the raptor has to keep hunting.

Some raptors are able to live in cities because they can find conditions similar to wild habitats. For example, peregrine (PER-uh-grun) falcons nest on cliffs in the wild. Now they have discovered that window ledges on skyscrapers make great nesting places too. There are plenty of pigeons and songbirds for the peregrines to catch on the wing. And people are thrilled to look out the window of a tall office building and see a falcon zooming past.


CONSERVATION STATUS

Of the approximately 300 species in the Falconiformes order, thirteen are listed as Critically Endangered, facing an extremely high risk of extinction, or Endangered, facing a very high risk of extinction. Another fifty-five are listed as Vulnerable, facing a high risk of extinction, or Near Threatened, close to becoming threatened with extinction. One reason so many are in trouble is that a lot of habitats have changed from forests and grasslands to farms and cities. When that happens, the prey animals that live in the habitats often disappear—the raptors that lived there cannot find the food they need, so they often move away or die off.

When raptors can no longer live in an area, this indicates that an environment may no longer be healthy for the all of the wildlife and humans living there. For example, if some poisonous chemicals get into a lake, they get passed along from little fish to bigger fish, as the fish eat one another. When an eagle eats a large fish from the lake, it takes in all of the poison passed along to the fish. In the 1950s and 1960s, bald eagles in the United States were laying eggs with such thin shells that they broke before hatching. It took some detective work by scientists to discover that the birds were being harmed by an insect poison called DDT. The poison was being passed along to the birds from the animals they ate, and these poisons were making the eggshells thin. DDT is now banned in the U.S. and the eagles are making a comeback. But it is still being used in many other countries, and conservationists are working hard to change that.


FOR MORE INFORMATION

Books:

Bailey, Jill. Birds of Prey. New York: Facts on File, 1988.

Clark, William S. Hawks of North America. Boston: Houghton Mifflin, 2001.

del Hoyo, Josep, A. Elliott, and J. Sargatal, eds. Handbook of the Birds of the World. Vol. 2, New World Vultures to Guineafowl. Barcelona: Lynx Edicions, 1994.

Jones, David. Eagles. Vancouver, Canada: Whitecap Books, 1996.

Parry-Jones, Jemima. Eyewitness: Eagle & Birds of Prey. London and New York: DK Dorling Kindersley, 2000.

Perrins, Christopher, ed. Firefly Encyclopedia of Birds. Buffalo, NY: Firefly Books, 2003.

Petty, Kate. Birds of Prey. New York: Gloucester Press, 1987.

Weidensaul, Scott. The Raptor Almanac. New York: The Lyons Press, 2000.


Periodicals:

Conover, Adele. "To Save a Falcon." Smithsonian (February 1999): 102–112.

"Eagles." Zoobooks (October 2002): 1–17.

Lohmus, A. "Are Certain Habitats Better Every Year? A Review and Case Study of Birds of Prey." Ecography (October 2003): 545–552.

White, Mel. "Raptor Central." National Geographic Traveler (May/June 2001): 6.


Web sites:

American Bird Conservancy. http://www.abcbirds.org (accessed on July 13, 2004).

Cornell Lab of Ornithology. http://www.birds.cornell.edu (accessed on July 13, 2004).

The Peregrine Fund. World Center for Birds of Prey. http://www.peregrinefund.org (accessed on July 13, 2004).

Raptor Research Foundation. http://biology.boisestate.edu/raptor (accessed on July 13, 2004).