Share: “Eastern Spot-billed Duck”
Order: Anserifomes, Family: Anatidae; Total length: 61 cm; Distribution: Asia
More than 30 species of ducks can be found in Japan. Most of them are winter birds, with the exception of the Eastern Spot-billed Duck, which is the only duck species that breeds in Japan and can be seen even in spring and summer. Its bill has a large yellow spot on the tip. Eastern Spot-billed Duck chicks cry "piyo piyo" while the voice of adults is husky, similar to that of domestic ducks.
Play birds singing
Ducks raise their young in the spring and summer just like other birds, but mate in the winter, which makes them unique. When male ducks migrate from Russia to Japan in the fall, their plumage has the same dull coloration as females. But as temperatures drop, the male's plumage becomes bright and colorful and he exhibits courtship behavior in pursuit of a mate.
Unlike other ducks, however, the plumage of Eastern Spot-billed Ducks does not change. Because the Eastern Spot-billed Duck is the only duck that breeds in Japan, it is thought that the male doesn't need to attract attention to itself with a flashy display of color.
Many birds, like ducks and pheasants, lay one brood of around 10 eggs every year. This, of course, raises the question: With so many young, don't they risk food or habitat shortages?
As a general rule, wild birds have many chicks, which grow up quickly. After hatching in the spring, they are capable of breeding the following year provided they make it through the winter. But, as they live in extreme circumstances, faced with natural predators, inclement weather, illness and injury, only a few young ducks are able to survive the bitter winter.
Because of their low survival rate, wild birds lay many eggs, raise their young quickly, and breed every year. The survival rate of insects and fish, which lay hundreds or even thousands of eggs, is likely far lower than that of birds.
Ducks often sleep during the daytime with their head rotated backward and bill under the feathers on the back. Aside from its bill, the Eastern Spot-billed Duck can be identified by the white crescent shaped pattern on its wings.
Two mallards appear in the foreground (left: female, right: male). To encourage selection by a female, the male's plumage becomes bright and colorful, but returns to the same dull coloration as the female in the summer. When mating season starts in the fall, the male's plumage again assumes a colorful appearance. The reason why each duck species has its own unique colorations is to ensure that females select a male within the same species.
