Effect of Abrupt Salinity Change in the Survival of Asian Green Mussel Perna viridis (Linnaeus, 1758) Spats

Abstract

Salinity is one of the key environmental factors that affects the growth and survival of marine organisms including mussels. Five different salinity levels (40, 30, 20, 10 and 5 ppt) were used to test the effect of abrupt salinity change in the survival of hatchery-produced spats of Asian green mussel Perna viridis (Linnaeus, 1758). Spats were stocked with a density of 30 individuals per 6-L tank. Salinity manipulation was conducted after 2 days from the date of stocking. Based on the results, abrupt change and prolonged exposure to lower salinities particularly of 5 and 10 ppt (up to 5 days) are detrimental to P. viridis spats.The critical time for P. viridis spats wherein they could seclude themselves from the persistent lower salinities is 28 hours from its exposure. After which, mortality could be high at about 50% and will continue in the succeeding days if low salinity persists. Critically, no single spat can survive until the 4 th day of continuous exposure to very low salinity of 5 ppt. Nevertheless, surviving individuals could still recover if salinity will return to optimum levels. Additionally, spats can readily adjust to abrupt change up to 10 ppt from the optimum salinity level as seen in the high survival in 20 and 40 ppt.

Growth performance and survival of oyster, Saccostrea cucullata (Born, 1778) and green mussel, Perna viridis (Linnaeus, 1758) cultivated in Bangladesh Coast

“…(2002) calculated 52% survival rate for three months culture system in Kovalam shore near Chennai. The study ofPicoy-Gonzales and Laureta (2022) showed that salinity in green mussel culture should be more than 15 ppt and total mortality occured at day 20 which is more or less similar to our present study. The shell height of S. cucullata (8.8±1.62 cm) was analogous in both culture items asOsei et al (2022) manifested the shell height of oyster, 3.23±0.43 cm, with the initial shell height of, 0.32±0.03 cm at 90 days of culture period which is lower in our present study (9.1±1.98 cm and 8.9±1.45 cm).…”