Crawdads, or crayfish, feed on small fish that can be captured with their claws, other invertebrates and plants, both living and dead. Those are that are kept in freshwater aquariums will eat regular and tropical fish food, shrimp pellets and various vegetables. Crayfish represent an important link in the food chain and are a food source for fish, such as bass, and water birds, such as herons.
Relatives of the saltwater lobster, which they resemble, crayfish are found in lakes, rivers, streams, brooks, swamps and marshes. They do not survive pollution, and their presence in a body of water is an indicator of environmental health and water quality. Considered a gourmet food and eaten worldwide, they are harvested on farms and trapped in wetlands. The Louisiana crayfish harvest was more than 50,000 tons in 2007, and the state produces the vast majority of crawdads trapped and harvested in the United States.