Shell valve movement response of dark false mussel, Mytilopsis leucophaeta, to chlorination

Shell valve movements of fouling mussel, Mytilopsis leucophaeta, have been studied in the presence of chlorine, using a mussel monitor. Data showed increasing shell valve closure with increasing chlorine concentration. Shell opening rates of M. leucophaeta at control experiments (0 mg litre−1 residual chlorine) were about 10 times more than those at 1 mg litre−1 residual chlorine. Continuous dosing of 0.75 mg litre−1 residual chlorine is required before shell movements are critically affected. Since current environmental stipulations do not permit this, a level of 0.5 mg litre−1 has to be used continuously during settlement periods of M. leucophaeta for their control. The results also indicate that M. leucophaeta is more tolerant to chlorine than other mussel species.