Mud crab nursery rearing practices

Abstract

The need for seeds for expansion of the mud crab industry led to the development of the hatchery technology. The nursery technology was developed as this served as a link between the hatchery, which produces megalopae or early crab instars, and the grow-out phase which requires bigger crab juveniles for a higher yield. The nursery has two phases, the first ending with production of crablets with 1- 1.5 cm carapace width (CW) and the second phase with crablets of 2.5-3.0 cm ICW. The more commonly recommended system employs stocking of megalopae or crab instars in net cages installed in ponds. Locally available unprocessed food and commercially available shrimp formulated diet are used for feeding. However, recent studies have successfully used formulated nursery diet for mud crab. One of the main problems in the nursery is cannibalism, and several strategies have been investigated and tried to address the problem.