Effect of salinity on the survival and growth ofChanda (=Ambassis) gymnocephalus (Lac.) fry (Pisces; Centropomidae)

Abstract

The survival and growth of Chanda (= Ambassis) gymnocephalus (Lac.) fry (8.8 ± 0.2mm) collected from Murukumpuzha Lake (9.34%) for a ninety day period in different salinity grades were studied. A faster rate of growth is exhibited by the fish in the highest salinity grades (22.41 and 28.51%), even though during the first month, growth and health was apparently better in the lower salinity grades (4.11, 10.21 and 16.31%). Assimilation efficiency also showed a similar gross picture. Thus inC. gymnocephalus, an euryhaline species, the fry show preferred salinity gradients for optimum growth within the fluctuating salinity regime at a stable temperature (26 ± 2°C) and hence may make salinity bound emigrations with growth.