Macrobrachium rosenbergii is the most common species of freshwater prawn (shrimp) cultured in the southern Illinois region. Post larval prawns (PLs) are stocked in late May or early June when water temperatures reach and maintain approximately 70°F. Stocking rates vary between 15,000 and 25,000 per acre. Initially the PLs feed on microscopic zooplankton and eventually begin the search for larger food items. In production ponds the introduction of specially formulated shrimp food composes the main diet of the growing prawns. The typical growing season for freshwater prawns in southern Illinois is approximately 100 days, not much unlike the length of time for conventional row crops. Harvesting of the prawns occurs prior to water temperatures falling below 65°F. Harvesting requires the draining of the pond. The prawns follow the receding water line and eventually exit the pond through the drain and are captured in a catch basin and placed on ice to ensure freshness. In 2002 Shawnee Freshwater Prawn Growers Association (SFPGA) members have over 30 acres of ponds in production with more than 1/2 million prawns stocked for harvest this late summer and early fall.

Adult males