Ducks are considered a common domestic species in most countries , and are featured in many popular children’s programs. But there are a vast variety of wild ducks that are seldom recognized. There are 131 species of wild ducks and geese in the world and Sri Lanka has recorded 18 species. Ducks are generally aquatic birds, mostly smaller than the swans and geese, and may be found in both fresh water and brackish water.
Ducks exploit a variety of food sources such as grasses, aquatic plants, fish, insects, small amphibians, worms, and small molluscs. 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 and to hold slippery food items.
The ducks are generally monogamous, although these bonds generally last only a single year. Larger species and the more sedentary species (like fast river specialists) tend to have pair-bonds that last numerous years. Most duck species breed once a year, choosing to do so in favorable conditions (spring/summer or wet seasons). Ducks also tend to make a nest before breeding, and lead their ducklings to water after they hatch. Mother ducks are very caring and protective of their young, but may abandon some of their ducklings.
Females of most dabbling ducks make the classic “quack” sound, but despite widespread misconceptions, most species of duck do not “quack”. In general, ducks make a wide range of calls, ranging from whistles, cooing, yodels and grunts.
One of the most common species of duck in Sri Lanka is the Lesser Whistling Duck also know as an Indian Whistling Duck. They are one of the only two resident species found in the country. They are found throughout the country, and sometimes in large numbers over 500-1000.
The balance species of ducks are winter migrants found mainly in the Northern parts of the island, such as Mannar and Jaffna. Mannar being a favorite among birders (bird watchers), its one of the best places to view these varying species of wild ducks. Among the most unusual is the Nothern Shovelor. This beautiful species have a strange “spatula” like bill. They use their highly specialized bill (from which their name is derived) to forage for aquatic invertebrates – a carnivorous diet. Their wide-flat bill is equipped with well-developed lamellae – small, comb-like structures on the edge of the bill that act like sieves, allowing the birds to skim crustaceans and plankton from the water’s surface. This adaptation, more specialized in shovelers, gives them an advantage over other puddle ducks, with which they do not have to compete for food resources during most of the year. Thus, mud-bottomed marshes rich in invertebrate life are their habitat of choices. The male is distinctively different from the female in coloration with a dark green head and white breast and chestnut flanks. The female is a drab mottled brown.
Another beautiful and colorful species is the Common Teal. With a myriad of colors which almost looks like its painted on the duck. This species though the name suggest common is seen in lesser numbers.
One of the most iconic, and distinctive species to migrate to Sri Lanka is the infamous Comb Duck or Knob Billed Duck. This species is a vagrant who is not a regular migrant but seen occasionally in the country. This large duck can be easily identified by the large fleshy mound on the bill of the male bird.
The preservation of these species in Sri Lanka goes hand in hand with the protection of the countries wetlands. These aquatic eco-systems are essential natural habitats for ducks and a variety of other water birds and wildlife. Sadly many areas are being cleared all over the country which has an impact on these species. A firm policy needs to be set in order to preserve the many species including the wild ducks who rely on these habitats for survival.