SUBLETHAL RESPONSE OF BARNACLES TO CHLORINE - AN EXPERIMENTAL-STUDY FOR POWER-PLANT BIOFOULING CONTROL

Results of the study on sublethal responses of Megabalanus tintinnabul um, an acorn barnacle exposed to different levels of chlorine, is pres ented. In control, juvenile barnacles showed increased filtration rate s, cirral activity and oxygen consumption per unit body weight as comp ared to larger barnacles. When both the size groups were exposed to ch lorine levels, filtration rates and cirral activity declined. In large r barnacles the decline in filtration and cirral activity was less pro minent. A decline in oxygen consumption observed in larger barnacles a ppears to be due to anaerobic metabolism under chlorinated conditions, when shell valves close. Juveniles appear to have normal oxygen consu mption rates and thus may be more prone to stress.