Shrimps Crabs and Lobsters: Decapoda

Most of the crustaceans harvested as food for humans are in the order Decapoda. Shrimps and crayfishes are raised on aquatic farms and sold as food throughout the world. Depending on where and what decapods eat, some species can become poisonous to the people that eat them. Others, if they are not cooked properly, may carry parasites that infest the bodies of people and make them sick.

In some areas, land crabs are considered pests in rice fields. They eat the rice plants and dig burrows that drain water away from the plants. The accidental introduction of the European green crab to the eastern coast of the United States has caused serious harm to clam beds harvested for food. Foreign species of crayfishes have damaged crops and threatened to reduce populations of native crayfish species.