The term Duck is the common name for a large number of species in the Anatidae family of birds, which also includes swans and geese. Ducks are divided among several subfamilies in the Anatidae family; they do not represent a monophyletic group but a form taxon, since swans and geese are not considered ducks. Ducks are mostly aquatic birds, mostly smaller than the swans and geese, and may be found in both fresh water and sea water. The overall body plan of ducks is elongated and broad, and the ducks are also relatively long-necked. The body shape of diving ducks varies somewhat from this in being more rounded. The bill is usually broad and contains serrated lamellae, which are particularly well defined in the filter-feeding species. In the case of some fishing species the bill is long and strongly serrated. The scaled legs are strong and well developed, and generally set far back on the body, more so in the highly aquatic species. The wings are very strong and are generally short and pointed, and the flight of ducks requires fast continuous strokes, requiring in turn strong wing muscles. Many species of duck are temporarily flightless while moulting; they seek out protected habitat with good food supplies during this period. This moult typically precedes migration. Ducks exploit a variety of food sources such as grasses, aquatic plants, fish, insects, small amphibians, worms, and small molluscs. Diving ducks and sea ducks forage deep underwater. Dabbling ducks feed on the surface of water or on land, or as deep as they can reach by up-ending without completely submerging. Along the edge of the beak there is a comb-like structure called a pecten. This strains the water squirting from the side of the beak and traps any food. The pecten is also used to preen feathers. A few specialized species such as the mergansers are adapted to catch and swallow large fish. You can subscribe to Mike on Facebook and his Photography Blog to follow his travels and join him on his photo shoots. |