Experimental Extensive Culture Of Penaeid Shrimp In A Simulated Dredged Material Disposal Area1

Abstract

ABSTRACTLarge amounts of soil and sediment are removed during dredging operations that dig channels, deepen harbors, and accomplish other activities necessary to maintain our navigable waters. Much of this dredged material must be disposed of in diked land disposal sites. The soft consistency of most of these sediments makes these containment areas unavailable for usual productive uses, such as agriculture, for periods of months or years.Shrimp mariculture in seawater overlying the sediment in disposal sites was proposed as a possible use of these areas. A preliminary evaluation was made by simulating a containment area.The bottoms of two 0.1 ha (1/4 acre) shrimp culture ponds were covered with a thick layer of freshly dredged channel sediment. Two adjacent ponds served as controls. All four ponds were fertilized and stocked with hatchery reared postlarval brown shrimp (Penaeus aztecus). No supplemental food was provided. At harvest 3 months later, average survival was 75%. Shrimp in the ponds containing dredged materials grew 30% faster than controls averaging 3.95 g. each (185 count per pound). The harvest rate averaged 100 kg. (220 pounds) per acre and was 19% higher in the experimental ponds.