A crawfish, or crayfish, is a freshwater crustacean related to the lobster. It should not be mistaken for the saltwater spiny lobster of the same name. Crawfish thrive in any body of fresh water, including streams, rivers, ponds, lakes and even water-filled ditches.
Crawfish create a home under debris and rocks on the muddy parts of streams and lakes by moving things around. They are night hunters, aggressive when defending their territories and omnivorous, eating plant materials, decaying organic matter, worms, insects and smaller mollusks. They are small; only a small part of the crayfish can be eaten. They also make good bait. They cannot thrive in polluted water.