"The harvest of crayfish for food in the United States now approaches 100 million pounds annually, with most of that coming from the state of Louisiana. This harvest consists almost entirely of the red swamp crayfish (P. clarkii) and the White River crayfish (P. acutus). In southern states the raising of these species involves filling and draining ponds on a yearly cycle. The ponds are drained in late spring to grow natural vegetation or crops such as rice that provide food for the crayfish when the ponds are refilled in the fall. The adults are in burrows during the dry part of the cycle, when the young are produced. The crayfish grow throughout the fall and winter period when the ponds are flooded, reaching a marketable size by early spring."