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DUCKS
WITH GREEN HEADS
What first occurs to your mind when one says "to waddle"?
Usually: waddling ducklings following their mothers.
Ducks have two techniques they use to feed themselves. While
swimming, without plunging underwater, some of them feed on
insects and plants. You often see them searching for food, with
their head and half of their bodies underwater. Some kinds of
ducks, on the other hand, search for food by diving underwater.
Their wide webbed feet help them to dive underwater but are not
good for walking on land. That is why they only leave the water
occasionally, except in the breeding season.
Water fowl such as ducks have air in their bodies. This is one of
the reasons they float on the surface of the water. In the duck's
body, there exist air sacs that look like tiny balloons. When these
sacs are filled with air, they help the duck to float. When the duck
wants to dive, it pumps the air out of the sacs and readily dives
under the water since less air remains in its body.
