Hawks and Eagles: Accipitridae

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HAWKS AND EAGLES: Accipitridae

OSPREY (Pandion haliaetus): SPECIES ACCOUNTS
HARRIS'S HAWK (Parabuteo unicinctus): SPECIES ACCOUNTS


This large family includes raptors (RAP-ters), birds of prey, of many shapes and sizes. One of the smallest species is the South American pearl kite that weighs less than 3.5 ounces (100 grams). At the other end is the Himalayan vulture weighing 26 pounds (12.5 kilograms). Raptors have keen eyesight and strong flight feathers.

Most of these raptors hunt during the day, and they kill the animals they eat. They can grab and kill prey with their curved talons (TAL-unz), claws, and tear meat with their hooked beaks. The Old World vultures from Europe, Asia, and Africa are the exception—they have weaker feet than the other birds in this family, and most of them are not able to kill the animals they eat.

Male and female raptors usually look alike, but the females are larger than the males. The birds' feathers are mostly gray, brown, or black, and some have lighter-colored chests, often with brown spots or streaks.


Hawks and eagles are found on all continents except Antarctica.


Sea eagles catch fish along coasts, but most raptors are land birds. They live in every kind of land habitat, including the tundra of the Far North, forests, wetlands, deserts, grasslands, mountains, and farmlands. They can also live in towns and cities with parks.


All hawks and eagles are carnivorous, meat eaters, and, except for vultures, they eat only freshly caught prey. Most of them eat any animal they can catch, but some have very special diets. For example, crab hawks eat crabs found in mangrove forests, snail kites eat snails, and ospreys eat fish.


The hawks with short wings and long tails are good at flying among the trees. Those with long, broad wings and broad tails are soaring birds that ride the air current to great heights. Some hawks, especially those that breed in cool climates, migrate long distances in fall and spring. Others live year round in their breeding areas.

Most raptors defend a breeding territory from other birds of their species, and they usually build their nests out of sticks. Large hawks and eagles lay one or two eggs, and the smaller species lay three or more. After the chicks can fly, they depend on their parents for several more weeks while they gradually learn to hunt.


Thousands of years ago, hawks and eagles were admired for their hunting skills and were even thought of as messengers of the gods. As early as 4,000 years ago, captive hawks were used as hunters to catch rabbits and other animals for their trainers. In modern times, some people kill hawks that are suspected of harming farm animals, but many other people enjoy watching them in their local habitats and on their long migrations.


Groups of birds are usually called flocks, but Harris's hawks act more like a pack of wolves. As many as six hawks fly in a line. When the one in front spots prey, it swoops to kill it. If the prey gets away, the next one in line swoops down. They take turns until the prey is tired and easily caught. Then they all eat together. Sometimes the birds attack their prey from different directions all at once. If the prey escapes under a bush, one hawk will crawl in and scare it out so the others can catch it. Together, the "pack" can catch a jackrabbit that weighs twice as much as a Harris's hawk.


Of the 236 species of Accipitridae, nine are listed as Critically Endangered, facing an extremely high risk of extinction in the wild, and four as Endangered, facing a very high risk of extinction in the wild. Another forty-five are listed as Vulnerable, facing a high risk of extinction in the wild, or Near Threatened, close to being threatened with extinction. Habitat loss is the main reason these birds are in trouble. In many countries, hawks and eagles are protected by law, and conservationists are doing what they can to preserve the habitats that these birds need.

OSPREY (Pandion haliaetus): SPECIES ACCOUNTS

Physical characteristics: Ospreys are medium-sized hawks, about 22 inches (56 centimeters) long from bill tip to tail. Their feathers are mostly black on the back and white on the front with a speckled "bib." Ospreys have sharply-hooked beaks and very strong feet with sharp talons that are good for grabbing slippery fish. The outer toe on each foot can be swung backward for an even stronger grip.

Geographic range: Ospreys that breed farthest north in Alaska, Canada, and northern Europe and Asia migrate to South America, Africa, and India for the winter. Ospreys live year round in Australia, the southern United States, and eastern China.

Habitat: Ospreys live near water of all kinds, both inland and near the ocean, including marshes, lakes, reservoirs, bays, seashores, rivers and estuaries, where salt water and fresh water mix.

Diet: Ospreys are sometimes called fish hawks because fish is about all they eat. They glide over shallow water and dive down feet first to grab fish with their sharp talons. By holding heavy fish with both feet, ospreys can carry them to land. Using their sharp beaks, ospreys tear the fish into bite-sized pieces.

Behavior and reproduction: Ospreys often build stick nests in trees near water. But they also nest on the ground on small islands and on sea cliffs. Females usually lay three eggs. Males bring fish to the females while they stay on the nest. Females keep the eggs warm and shelters the chicks from cold winds and the sun's hot rays. After the young birds can fly, they stay with their parents for a while. If their parents migrate, the young birds will fly south with them.

Ospreys and people: Biologists build nesting platforms on tall poles in the water for the ospreys. The birds like to nest on the platforms, because they are safe from raccoons and other mammals that steal their eggs.

Conservation status: Ospreys are not threatened. ∎

HARRIS'S HAWK (Parabuteo unicinctus): SPECIES ACCOUNTS

Physical characteristics: Harris's hawks have mostly dark brown feathers, but their shoulders are red-brown and their tail feathers are black with white tips. Their length is between 19 and 22 inches (48 to 56 centimeters) from the bill tip to tail.

Geographic range: Harris's hawks live in southwestern United States, Mexico, Central America, and South America.

Habitat: As long is there is water nearby, Harris's hawks can live in desert areas. Some of the birds live in grasslands and a few use wetlands. They also need an area where there are a few trees, tall saguaro cacti (KACK-tie, or KACK-tee), or electrical transmission towers where they can build nests.

Diet: Harris's hawks eat mostly hares, rabbits, birds, and lizards. They can kill prey that is large for their size because they hunt in groups of two to six hawks.

Behavior and reproduction: Harris's hawks are more sociable than most hawks. They build stick nests and line them with moss, grass, and leaves. Females lay between one and four eggs. Males bring food to the females and help defend the nest, and occasionally males will sit on the eggs. In desert areas, females must shade the eggs and chicks from heat. Often other Harris's hawks, usually young birds that are not breeding, help to feed the chicks and guard the nest. Some pairs raise two families in the same year. Often the young of the first nest help to raise the second set of chicks.

Harris's hawks and people: Biologists and bird lovers are fascinated by Harris's hawks. Because the hawks are so sociable, they behave in ways that are unusual for birds and interesting to study.

Conservation status: Harris's hawks are not threatened. ∎


Physical characteristics: At about 4 pounds (1.8 kilometers), the Egyptian vulture is one of the smaller Old World vultures. Their length is about 25 inches (63.5 kilometers) from bill tip to tail. They have bright yellow skin on their faces and a "mane" of white feathers on their heads. The rest of their feathers are also white, except for black flight feathers.

Geographic range: Egyptian vultures live in Africa and India year round. The birds that breed in northern Africa, Europe, and Asia, north of India, migrate to warmer areas after breeding.

Habitat: Egyptian vultures like dry, wide-open lands, including deserts, grasslands, farm fields, and pastures. They also live in cities, where people welcome them as a clean-up crew.

Diet: Like all vultures, Egyptian vultures are scavengers, eating mostly carrion, dead animals. They also eat garbage, insects, eggs, and occasionally live prey. They are famous for their ability to break open thick ostrich eggs by throwing stones at them. Very few birds know how to use tools that way.

Behavior and reproduction: Egyptian vultures usually build big, messy stick nests on rocky ledges or in caves. Where there are no rocks, they build their nests in trees. They usually lay two eggs, and, unlike most raptors, the parents regurgitate, bring up from the stomach, food to feed the chicks.

Egyptian vultures and people: An Egyptian pharaoh once made a law that anyone who killed an Egyptian vulture would be put to death. He thought the job these birds did to clean up people's waste was very important. People still value the bird for that reason. More than a century ago, the bile from Egyptian vultures' livers was made into a medicine and their skins were tanned to make leather.

Conservation status: Egyptian vultures are not threatened. ∎



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