Click to Enlarge Duck bill identification (right photo): Mallard (top bill), Northern Shoveler (middle bill) and Common Merganser (bottom bill) Click to Enlarge Duck identification: Mallard (top left image), Hooded Merganser(rop right) and Northern Shoveler(bottom left)   Duck Bills By Ryan P. Kelly, illustrations by David Besenger The shape of its bill can tell you what a duck If you were to picture a duck bill in your head, what image would come to mind? Would it be the familiar bill of a mallard, the slender, pointed bill of a merganser, or the spoon shaped bill of the northern shoveler? Each fall and spring, a variety of duck species visit Missouri's wetlands. As the ducks migrate north and south, they stop at these wetlands to rest and eat various plant and animal species. Not all duck species feed in the same manner, and they don't all eat the same things. The shape, size and structure (how the bill is built) of the duck's bill reflect what and how a particular duck eats. Let's look at three different ducks that are commonly found in Missouri's wetlands and learn why their bills are different. Mallard The mallard has what you might call a typical duck's bill. The bill isn't very long, but it's not very short, either. It's not overly wide, nor overly narrow. It's a very versatile bill because it lets the mallard eat a wide assortment of plants and animals, from microscopic plant seeds to snails and acorns. Wildlife biologists consider mallards to be "gen-eralist feeders." That means they'll eat whatever food is available. Although mallards sometimes eat insects, plankton and even snails, more than 90 percent of a mallard's diet comes from plants, They mostly eat wetland plants, but they'll also consume land plants, including grasses and crop plants like wheat, barley, rice, oats and peanuts. If you look closely, you can see a kind of serrated fringe along a mallard's bill. This uneven edge not only allows it to grip food more securely, but it also strains tiny plants and animals from water or mud. Hooded Merganser Hooded mergansers, which are also commonly found in Missouri, have a different shaped bill than mallards. Their bill is long and narrow, with a pointed tip and sharp serrations that look like teeth. These serrations help the hooded merganser grab and hold food. The narrow bill makes the bird more streamlined for when it searches underwater for food. Mergansers are strong swimmers and are some-times called "fish ducks." The hooded merganser, however, eats less fish than other species of mergan-sers. They usually feed near shore where they dive for small fish, crayfish and aquatic insects. The long, narrow bill helps the hooded merganser swim through the water while hunting for its prey. If its bill were shaped like a mallard's bill, the mer-ganser would have a hard time moving through the water. It would also be more difficult to grab a small fish or insect if the tip of the bill were not pointed. Northern Shoveler The northern shoveler is named because its bill looks like a shovel. Its bill is about 2.5 inches long. It flares near the tip, reaching a width of about 1.25 inches. The end looks like someone stepped on it. Shovelers are part of a group of ducks known as "dabblers." This group includes mallards, wigeons, pintails and teal. Shovelers eat many of the same foods as other dabbling ducks, including insects and plants. They also have a unique method of feeding, and the strange shape of the bill plays an important part in it. Shovelers usually don't "tip up" to reach under the surface like other dabbling ducks. Instead, they swim with their head down, straining food from the surface of the water. They often feed in groups in shallow water. The ducks stir the mud with their feet as they feed, bringing even more food particles to the surface. The shape and size of the northern shoveler's bill assists it when feeding. Inside the bill are hair-like lamellae that filter or strain food from the water. A northern shoveler feeds by taking water into its mouth and then pushing it out the base of its mouth. The lamellae trap food inside the bill. Nerve endings on the ducks mouth and tongue help the shoveler tell what is edible. The flat end of the bill moves through the water with ease. If the bill were not flat at the end, it would be harder to move through the water. A simple experiment helps demonstrate the value of the unique shovel-shaped bill. Move a spoon through water so that the cup of the spoon catches water. Now turn the spoon. See how much easier it moves when its edge cuts through the water!Many other ducks have unique bill shapes. The next time you see a duck, try to figure out what the duck eats by looking at its bill. Did you know? Ducks do not have teeth. The lamellae look like teeth, but are formed out of the hard material of the mandible. The top half of the duck's bill, called the upper mandible, is an extension of the skull. It cannot move. Only the lower mandible is hinged. It does all the moving. The button-like formation at the end of the mandibles is called the "nail" and is hard, much like a human fingernail.