Effect of environmental variables on the growth of Asian green mussel Perna viridis (Linnaeus, 1758), in two different aquaculture systems in Goa, west coast of India

Asian Green mussel Perna viridis (Linnaeus, 1758), is a bivalve mollusc with high market demand along India's western coast, specifically in Goa. An experiment was conducted to compare the environmental variables, specific growth rate (SGR) and length-weight progression of the species raised in two different coastal aquaculture systems; a semi-enclosed water body (SEW) and an open-water system (OWS). The variables chlorophyll-a and plankton density were high in SEW and these variables were positively correlated with the growth rate of the species. The `b' value of the length-weight relationship and SGR were found high and allometric in nature in SEW. The prediction of SGR using the generalised linear model has indicated that plankton density and nitrate level are the variables that influence the growth of P. viridis. Thus, being a predominant filter-feeder on plankton, the high plankton density channeled through the rich nutrients and chlorophyll content might have triggered the growth of mussels in SEW. India is blessed with many semi-enclosed coastal water bodies lying unutilised, and the results indicate that there is scope for mussel culture in these systems, which will provide a source of secondary livelihood for the coastal fishers.