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Swan: Characteristics, Diet, and Behavior of These Majestic Birds

 
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Introduction to Swan

Swan, a migratory water bird related to ducks and geese. Larger than the goose, the swan may attain a length of five feet (1.5 m) or more. Its long, graceful, arched neck allows it to dip into the water and gather the aquatic plants and seeds that form the major part of its diet. The male swan, called a cob, is larger than the female, or pen. The young, called cygnets, have bluish-gray or brownish feathers. With the exception of the black-necked swan and the black swan, the plumage of adults is white.

Swans are large migratory water birds related to ducks and geese.

Swans gather in flocks, and a mated pair may stay together for life. The nest is usually a wide mass of rushes and reeds, lined with down, built near the water's edge. The female lays two to seven whitish eggs, each about four inches (10 cm) long.

Do Swans Mate for Life?

Swans usually do mate for life. But there are times when a swan does take a new mate. A swan may take a new mate if its partner gets lost or dies.

Swans choose mates when they are 2 to 3 years old. A swan begins its courtship by displaying, or showing off, to another swan. Swans display while facing each other. They dip and turn their heads. Swans may also “kiss” bills. When swans kiss, their necks form a heart shape.

Many swan pairs set up territories. A pair picks a territory where there is a lot of food and a safe place to build a nest. Swans defend their territories fiercely. They fight off an intruder by bumping it and hitting it with their wings. When the intruder leaves, the swan pair celebrates. They call loudly and face each other with raised wings.

There are seven species of swans. The tundra swan nests in arctic regions of North America and Eurasia and winters in temperate regions. The tundra swan grows to a length of about 55 inches (1.4 m). It has a black bill, usually with a yellow spot at the base. The tundra swan has a high-pitched call. Tundra swans of North America are also called whistling swans ; those of Eurasia, Bewick's swans .

The trumpeter swan was once close to extinction, but through conservation measures its numbers have increased. Largest of the swans, trumpeters can reach a length of more than 70 inches (1.8 m) and a weight of more than 30 pounds (14 kg). They have black bills and give a deep, hornlike call. These birds nest mostly in Alaska and winter in Canada. Smaller flocks are found south of Canada in a few parts of the western United States.

How Do Trumpeter Swans Sound Off?

Trumpeter swans sound off with trumpetlike calls. How do they do this? A trumpeter swan has a very long neck. Inside the neck is a long trachea (TRAY kee uh), or windpipe. The trachea is so long that it even winds around the trumpeter’s chest bone. It lets a trumpeter swan make its deep, hornlike calls. Trumpeter swans are the loudest of all swimming birds.

Pairs of trumpeter swans set up large territories. They need their loud calls to stay in touch with each other. Their calls are also a way to say: “Stay out of our territory!”

Swans are very vocal birds. The trumpeter swan, the whistling swan, and the whooper swan are all named for their calls. So you might think that the mute swan is mute, or silent. But even mute swans hiss, snort, and give off trumpetlike notes.

The domesticated mute, or common, swan is the species commonly seen in parks. It has an orange bill with a black knob at its base. The mute swan is native to Eurasia and has been successfully introduced into North America and Australia. Despite its name, it is not mute; it occasionally gives a barklike call. The black-necked swan is native to southern South America. It is white with a black neck; its bill is red. The black swan is native to Australia. It has a bright red bill and is entirely black except for white wing feathers that are visible only during flight. The whooper swan, of Eurasia, has a black and yellow bill. The coscoroba swan, of South America, is the smallest swan; it grows to a length of about 30 inches (76 cm).

The tradition that a dying swan produces a beautiful song—the “swan song”—is without basis in fact.

Where in the World Do Swans Live?

Swimming birds can be found on every continent—including Antarctica. Swans, however, live on just five continents. These swimming birds prefer places that have mild or cool climates. Swans do not live in Africa, where the temperatures get very hot. And they do not live in Antarctica, where temperatures are too cold.

There are seven species, or kinds, of swans. Four species live in the Northern Hemisphere, and three species live in the Southern Hemisphere.

Where a swan lives tells you a little bit about it. For example, swans that live in the Northern Hemisphere have only white feathers. Swans that live in South America have either black wing tips or black necks. Australian swans are nearly all black. Northern swans are also larger than southern swans.

Swan Signals

What Makes Swans Good Swimmers?

Swans have many features that make them good swimmers. They have webbed feet, air sacs, waterproof feathers, and widely spaced legs.

Like most birds, swans have four toes on each foot. But swans also have webs of skin between three of their toes. To swim, they use their webbed feet like paddles.

Swans have air sacs connected to their lungs. They also have hollow bones. The air sacs and hollow bones act like life preservers. They help keep swans afloat.

Under their feathers, swans also have downy coats. The down traps pockets of air. This keeps the swan warm. It also helps the swan float.

Finally, a swan’s legs are set wide apart and far back on its body. This helps the bird keep its balance and paddle through the water.

When Do Graceful Swans Look Clumsy?

Swans are very graceful fliers. They flap their big, strong wings with powerful beats. They fly with their necks stretched out and their legs tucked in. But swans are large and heavy birds. Like this mute swan, they have trouble taking off and landing. That’s when swans look clumsy.

When swans want to fly, they need to gather up speed to help them take off. For this, swans need a runway. The runway is usually a long stretch of land or water. Swans pat across the water, flapping their wings as fast as they can. At first, they look clumsy. But once they are in the air, they can fly very well.

Landings can be tricky for swans. This may be why many swans choose to land on the water. To land, swans spread out their wings and their tail feathers to catch the air and slow down. Then they put their feet forward and use them as brakes to touch down.

What Do Swans Eat?

Swans eat mostly water plants. And they eat all the parts—leaves, stems, roots, and seeds. Swans eat plants found on the surface of the water, along the shore, and under the water. Young swans eat small animals, such as insects, worms, and tiny fish. In winter, swans may come on land to feed.

Swans use their long necks to reach underwater plants. To do this, a swan puts its neck under the water and upends, or raises its tail into the air. When a swan upends, it can reach down about 3 feet (1 meter) under the water.

A swan has a wide, flat bill with tiny, teethlike fringes along the edge. The bill is good for biting and tearing water plants. Swans open and close their bills quickly to squeeze water from their food. The fringes trap the food and let the water drain out.

How Do Swans Care for Their Feathers?

Swans care for their feathers in different ways. First, they take a lot of baths. They also preen, or use their bills to care for their feathers.

To bathe, swans may hold their wings open and dive underwater. Then they come up and roll along the surface of the water. Swans dry off by flapping their wings and shaking their bodies.

Swans spend a lot of time preening. When swans preen, they use their bills to straighten and rearrange their feathers. They use their bills to remove any insects from their feathers. And they use their bills to waterproof their feathers.

How do swans waterproof their feathers? A swan has a gland at the base of its tail that makes oil. The swan uses its bill to spread this oil over its feathers. The oil waterproofs the feathers.

Why Are Swans Sometimes Grounded?

When swans are grounded, it means that they can’t fly. This happens when swans molt, or shed their old feathers and grow new ones. If you look closely at the swans in this picture, you can see where they have shed their feathers.

Swans molt because their feathers wear out and need to be replaced. Swans usually molt once a year, during the summer months. With some species of swans, the males and females molt at different times. First the female molts. Then the male molts.

The molt lasts about six weeks. During this time, the swan cannot fly. But it can still swim. So molting swans stay close to the water. This makes it easier to find food and to escape from enemies.

Where Do Swans Go in Winter?

During the winter, many swans migrate, or travel long distances. They leave before the rivers and lakes freeze. Migrating swans fly to warmer climates or to places where they can find more food. Other swans do not migrate at all. They live by bodies of water that don’t freeze.

Some swans travel to the seashore where the water is salty. The food is often salty, too. Swans have special salt glands that help get rid of extra salt. The salt comes out the swan’s nostrils in a liquid like tears.

Swans may migrate more than 1,000 miles (1,600 kilometers). To prepare for this flight, a swan eats a lot of food. It stores the food as fat. The stored fat is like a fuel tank. It gives the swan the energy to fly long distances without stopping.

Migrating swans travel in family groups or in flocks. They usually fly in clear weather and use the sun or stars to guide them.

Where Do Swans Build Their Nests?

All swans build their nests near water. Some build nests on the ground. Others build nests on plants floating on the water. Swans may also patch up a nest they used the year before.

Swans nest in the spring or early summer. The cob, or male swan, usually chooses the place and gathers the materials. He passes grass, twigs, and other plants to the pen, or female swan. The pen uses the plants to build a nest that may be more than 9 feet (3 meters) wide.

After laying her eggs, a pen sits on the eggs to incubate them, or keep them warm. The cob stays close by to guard the nest. Sometimes, a cob sits on the nest while the pen feeds.

After 30 to 35 days, tiny cheeps can be heard from inside the eggs. One by one, the baby swans hatch. The babies are called cygnets (SIHG nihts).

Are Swans Ever Ugly Ducklings?

Some people think cygnets look like ugly ducklings. But if they do, it’s not for very long. At first, the young cygnets are wet and scrawny looking. Then they dry off and become tiny balls of fluffy down.

When cygnets hatch, they weigh about 6 ounces (170 grams). That’s about the same weight as a baseball. But an adult swan can weigh up to 26 pounds (12 kilograms). That is much larger than any duckling can grow.

After a day, cygnets can follow their parents into the water. They already know how to swim. But they won’t be able to fly for 7 to 20 weeks. Until then, their parents swim or walk with them. Some swans even carry their young on their backs.

How Do Swans Care for Their Cygnets?

Cygnets grow more slowly than other swimming birds do. They need their parents for a longer time, too. Their parents help them find food and stay safe.

A few days after hatching, cygnets are ready for their first meal. Their parents help by pulling up underwater plants. Soon, cygnets are able to peck at water plants and insects on their own.

During the day, cygnets stay close to their parents. If a cygnet wanders off, a parent calls to it. And cygnets call to their parents if they need help. At night, cygnets sleep in the nest, safe and warm under their mother’s wings.

Cygnets stay with their parents for about a year or two. This gives young swans time to learn such things as migration routes. Some swans stay with their parents until they are ready to choose mates of their own.

Swans belong to the family Anatidae. The tundra swan is Cygnus columbianus; the trumpeter swan, C. buccinator; the mute swan, C. olor; the black-necked swan, C. melanocoryphus; the black swan, C. atratus; the whooper swan, C. cygnus; the coscoroba swan, Coscoroba coscoroba.