Is This Bird a Duck, Goose, or Swan?


How can you tell if a bird is a duck, a goose, or a swan? The best way is to look at the shape of the bird’s bill. As a rule, ducks have rather long bills that are wide and flat. Geese have bills that are shorter and more rounded. Swan bills are halfway between the bills of ducks and geese—rather long and thick. A fourth kind of bill is found on fish-eating ducks called mergansers. The merganser bill is very long and round.

The bill shapes of all these types of waterfowl are different because each type of bird eats a different kind of food. On these pages, you will see how waterfowl use their various kinds of bills to get their various kinds of food.

Mergansers use their bills for catching fish most of the time. For this reason, their bills are long and thin, with tooth-like serrations along the edges. When a merganser grabs a slippery fish, the serrations dig into the body of the fish and keep it from slipping out of the bird’s mouth.

Many types of waterfowl dive to get some of their food. But mergansers and sea ducks get almost all of their food by diving.

Some waterfowl have crests (or hoods) on their heads. The crests can be raised or lowered. This merganser has its hood up.

All waterfowl have thick bodies with rather short and sturdy legs. All of them have large feet with webbing between the toes, to help them swim.

Swans like to feed on plants that grow under the water. They pull the plants out by the roots or bite them off. For this purpose, they have bills that are thick and strong. The long necks of swans sometimes make it possible for them to get food from the bottom without diving for it. If the water isn’t too deep, they can simply reach down from the surface and pull up all the plants they want.

Most waterfowl have hooks at the end of their bills. Because the hooks look like human fingernails, they are called “nails.”

Geese like to eat grass and other tough plants. To help them tear off clumps of grass, they have very sturdy bills. The small serrations inside the bills are used to slice up the grass before it is swallowed.

Many kinds of ducks feed themselves by straining tiny bits of food out of the water. This method of getting food is called dabbling, and the ducks that do it are called dabbling ducks. The ducks swim along with their mouths open, and let water flow into their bills. The rounded serrations inside the bill strain bits of food out of the water, as shown below.

Dabbling ducks eat almost anything that floats into their mouths—seeds, waterweed, and many other things.

Dabbling ducks must strain many gallons of water to get the food they need. The water and food flow into the bill together. The serrations keep the food in the mouth to be swallowed, while the water is allowed to flow out of the mouth.

Wood ducks nest in some surprising places! To find out where, go to