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Animals and Plants > Common Animals

Crayfish (many species)

Crayfish are small, shrimplike animals that live on the bottom of streams and lakes. They are closely related to lobsters, and they look like miniature lobsters. On average, crayfish are 7.5 cm (3 in). During the day, they spend most of their time hidden under rocks and fallen branches. At night, they are active, crawling slowly along the bottom, looking for food. Crayfish eat algae, fish eggs, insect larvae, worms, some water plants, and detritus. Animals that prey on crayfish include alligators, turtles, raccoons, and birds.

Crayfish have a hard outer skeleton. Throughout their life, they shed their hard outer body so that they can grow in size. The process of shedding their outer body is called "molting." After they molt, their soft bodies grow in size rapidly. In time they grow back a new, larger hard outer body. And, if a crayfish loses a leg, it can grow it back.

During cold winters, crayfish build burrows and live in them. They capture food items that float or swim past the entrance to their burrows. In the spring, the crayfish come out of their burrows. At this time, females have eggs. The eggs are attached to the female below her tail. The eggs are very small and are tightly packed in a ball. It looks like the female has a big berry under her tail. The eggs hatch in May or June. The new baby crayfish stay under their mother's tail for a few days before swimming off on their own.