Crayfish, also called crawfish, is a freshwater animal that is closely related to the lobster. Hundreds of species of crayfish live in North America. Crayfish are also common throughout Australia, Europe, and parts of Asia. Their habitats include lakes, swamps, and streams. Most crayfish measure from 2 to 6 inches (5 to 15 centimeters) long.
Crayfish belong to a group of animals called crustaceans. Like other crustaceans, they are covered by a hard, protective structure known as the exoskeleton. As a crayfish grows, it molts (sheds) its exoskeleton periodically and grows a new, larger one.
The body of the crayfish is divided into three main sections: (1) the head, (2) the thorax, and (3) the abdomen. The head and thorax are rigid, but the abdomen has flexible parts. Five pairs of legs extend from the sides of the thorax. The front pair are shaped into large claws. Several small reproductive structures called swimmerets hang from the abdomen.
Crayfish eat many kinds of plants, as well as snails, tadpoles, and fish. They are generally more active at night, returning to safety under a stone or inside their burrow during the day. When they are molting, crayfish lose the protection of their exoskeleton. As a result, they typically hide from their enemies for several days until a new exoskeleton hardens. In North America, crayfish are a favorite food of smallmouth bass and other sport fish. For this reason, crayfish are often used as bait by fishing enthusiasts.
Crayfish are a popular food in some parts of the world, particularly the Southern United States and the Scandinavian countries. In the United States, especially in southern Louisiana, crayfish are harvested from their natural habitats and raised on commercial “farms.”
