Salinity tolerance and fishery of mud shrimp Solenocera crassicornis (H. Milne Edwards) in the coastal waters of Mumbai

Abstract

Salinity tolerance of mud shrimp Solenocera crassicornis investigated at different salinities ranging from 15‰ to 55‰ showed that shrimps in the salinity range 30‰ - 42‰ survived but those in lower and higher salinities died soon after the transfer. Ionic concentration in the hemolymph and free amino acids in the body muscle in response to different salinity ranges showed hypo-regulation initially but later became hyposmotic to the medium and died eventually when the salinity decreased. The abundance of shrimp showed inverse relationship with rainfall and consequent lowering of salinity in the inshore waters. The study showed that S. crassicornis can regulate osmotic and ionic concentrations of body fluids efficiently in the salinity range of 30 - 42‰ but unlike euryhaline penaeid shrimps it is a poor regulator at lower salinities and therefore it migrates offshore during monsoon months.