Ducks can and can't get into the water. A landlubber refers to a duck that never gets into the water. Ducks can swim, but they are not allowed to go into the water. Ducks usually raised on land are collectively called landlubbers. The earliest metaphor of a landlubber is not a person who can't swim, but a person who has never been in the water. Now just let people extend the meaning to people who can't swim.

A duck raised in the south of China, with dark green feathers and reticular crown tissue on its head, is bigger, clumsier and denser than ordinary ducks. Eat a lot, twice as much as ordinary ducks.

There are about 15 species of small birds in the family Anatidae. Found on six continents and many islands. It belongs to the drilling duck family. Most of them are popular bird hunters. The most famous is the green-winged water duck in the whole northern region, which is about 33 ~ 38 cm (13 ~ 15 inch) long and often forms a dense group. Blue-winged water ducks are small in size, breed in Canada and vast areas in the northern United States, and winter in the southern United States.

Guihong duck is also distributed in North America, with bright colors, reddish feathers and blue wing spots. Houghton Duval ducks distributed in Africa are very heavy, and even if hunters shoot nearby, they often stay motionless in the vegetation. Water ducks are mainly herbivores, but some species (such as blue-winged water ducks) may have 25% animal food. A variety of water ducks take off together in groups and change the flight direction together. Also known as "Lake Duck".

In north and north China, there is a bird that lives in fresh water. It is about the size of a pigeon, its feathers are gray, and its body is about the same as that of a molting pigeon. Generally live in ponds or rivers with aquatic plants. It can fly or dive and feed on algae or small fish, but it will damage the environment.