Its call is a loud "honk" that sounds like a trumpet.
Trumpeter swans live near lakes, ponds, rivers and streams in the northern continental United States, western Canada and Alaska.
They generally weigh between 17 and 30 pounds, with females averaging about 22 pounds and males averaging about 28 pounds. They can be over 5 feet long with wingspans of almost 7 feet.
Adults have white feathers, with black faces, bills, legs and feet.
Cygnets have grayish plumage. They have pink legs and some pink on the tips of their bills.
Trumpeter swans mostly eat aquatic plants. They sometimes eat grass and grains on land.
Young trumpeter swans eat insects and other small invertebrates, such as small crustaceans.
Some trumpeter swans migrate, especially those that breed near bodies of water that freeze in winter.
A trumpeter swan can have a long lifespans. Wild trumpeter swans can live for over 20 years.
Trumpeter swans are monogamous. They often mate for life, but sometimes a swan will leave its mate and find a new mate. Sometimes, if a swan dies, its partner will never mate again.
A trumpeter swan nest is bowl-shaped. It is made of aquatic plants and grasses and lined with down and feathers.
The nest is elevated, and often surrounded by water. It might be built on top of a muskrat lodge or a beaver lodge. Sometimes the nest is built on top of a small island or on a floating platform made of plant matter.
Nests are large - possibly 5 or 6 feet in diameter.
A clutch can contain between 2 and 7 eggs.
The female incubates the eggs, and both parents raise the young.
A cygnet can leave the nest to feed and swim within a day of hatching.
Hundreds of years ago, trumpeter swans were found all over central and western North America.
Between the 17th and 19th centuries, they were hunted for their meat and for their beautiful white feathers.
The flight feathers of trumpeter swans were used to make quill pens.
Trumpeter swans were almost extinct by the beginning of the 20th century. The number of trumpeter swans has increased because of conservation efforts.
Trumpeter swans are now protected by law in Canada and the United States.
Many trumpeter swans have died of lead poisoning after swallowing lead shot pellets.