Defining the Duck
Before you dive in, find out all the essential facts about your ducks.
All birds — including the captivating duck — possess adaptations that set them apart from most other backboned animals, or vertebrates. Of course, the unique avian characteristic that attracts and delights us most of all must surely be feathers! What else gives these animals their eye-popping range of colors and contributes so much to their enviable power of flight? But birds have more going for them than just feathers; they’ve evolved some other interesting and useful features you should know about, too.
How BIRDS Are Built
The wild ducks from which our domestic duck breeds descend can fly fast, far and high, thanks to a number of specialized adaptations. A flying bird’s skeleton is light and strong, consisting of thin, often air-filled, or pneumatic, bones. The bones that make up the wings evolved from the forelimbs of the birds’ dinosaur ancestor (some bones being fused and some eliminated down through the ages).
The breastbone has a large protrusion called a keel, to which the highly developed wing muscles attach. Most birds have more cervical vertebrae than other vertebrates do. If you’ve ever seen a duck preen or a swan arch its graceful neck, you know that most birds also have neck bones more flexible than ours.
Unlike us, birds have no teeth; the avian jaw is narrow and elongated, forming a horncovered, toothless beak. Birds’ beaks vary in shape and size, each type adapted to handling the specific foods in the species’ diet. In most birds, food travels down the esophagus and enters an expandable storage chamber called a crop. From there, it moves into a stomach consisting of two chambers: the proventriculus, which secretes gastric juice as does the human stomach, and the muscular gizzard.
Standing in for teeth, the gizzard grinds seeds, grains, insects and other foods with the help of ingested stone particles called grit, which the bird picks up as it forages. Avian digestive, urinary and reproductive systems all terminate in one chamber, known as the cloaca, where urine and fecal material mix together and then exit the body
via the vent. As we all know, birds reproduce by laying eggs, a characteristic they share with reptiles and their dinosaur ancestors.
In general, birds have terrific eyesight. The duck, for example, sees colors, and each of its eyes has a visual field of more than 180 degrees, giving it binocular vision to the front, to the rear and even overhead — a huge plus for spotting sneaky predators. Birds’ hearing is also well developed, but their sense of taste is poor, and with the exception of some species, such as vultures, so is their sense of smell.
Birds have a rapid heart rate, a high metabolism and an active lifestyle that requires them to consume plenty of food. Avian body weights range from a fraction of an ounce (the bee hummingbird) to more than 300 pounds (the ostrich). A bird’s compact lungs connect to air sacs that branch out through its body, an amazingly efficient respiratory system that allows a migrating swan to fly at 20,000 feet in altitude and a ruby-throated hummingbird to beat its wings up to 70 times a second. This efficient respiratory system, along with a high metabolism, also accounts for birds’ extreme sensitivity to breathing toxic substances.
Birds are so susceptible to toxic gases that, historically, coal miners were able to rely on this avian attribute to save their own lives. They took canaries into the mines with them to serve as an early detection system: the birds’ demise warned them of the presence of deadly gases.
Specific waterfowl traits
Although lots of birds spend time around water, what we normally refer to as waterfowl are swimming game birds in the family Anatidae: ducks and their larger relatives, geese and swans. About 150 species of waterfowl are found throughout the world, occupying every continent except Antarctica. More than 50 of these species inhabit North America, most of them migratory to some degree. In their wild state, these birds rule the waters, swimming, diving and dabbling (that is, feeding in shallow water). But they can fly high in the sky and waddle across land with varying degrees of success as well.
All waterfowl, domestic and wild, share certain important physiological traits and behaviors. Here’s a speedy overview of the ones that will help you better understand the domestic duck.
Webbed Feet & duck bills:
Look at a Mallard, and you see a bird built for a semiaquatic life. Large webbed feet propel its streamlined body along the surface of lakes and keep it from sinking into the soft mud of marshes and estuaries. Its short legs sit toward the middle of its belly, allowing the duck to walk on land and achieve an explosive takeoff from water. By contrast, a heavier diving duck, such as the merganser, has legs situated back near the tail and needs a running start to get airborne.
Now check out that funny-looking bill, yellow in the Mallard male (or drake), orange and black in the female (or duck). Mallards and their domestic descendants are called dabbling or puddle ducks. At times, they submerge themselves completely, but more often, they bob around on top of shallow bodies of water, using their broad bills to dabble for floating plant material, bugs and mosquito larvae. They also tip tails-up to scrounge around in the mud, sifting out the edibles with their lamellae — comblike plates lining the upper and lower bills. That big bill