Fishery of the sand lobster Thenus orientalis (Lund) by bottomset gillnets along Tamil Nadu

Abstract

Sand lobsters are generally landed as a by-catch in shrimp and cephalopod trawl nets operating in coastal waters (20-60 m depths). The resource is most abun-dant off the north-west and south-east coasts. With the increase in demand for sand lobsters in export market, the resource achieved prominance in exploitation. The gear used predominantly was “pannu valai” operated as a bottom-set gill net. Generally the mesh size of this net varies from 60-65 / 80-85 mm and net is approximately 1-1.5 km long. The size group analysis indicates the dominance of juveniles and sub-adults in shallow depths and a preferential movement of the animals with increasing size and maturity towards deeper waters and possibly towards a lower temperature regime.