Biology of the Green Mussel, Mytilus viridis

Abstract

Growth rate, breeding periodicities and larval abundance in Mytilus viridis in the environmental waters have been studied from Panaji and Vengurla along the central west coast of India during 1972-75. The data show that the modal sizes attained by the mussels at the end of 1st, 2nd and 3rd yr of their lives are respectively 96, 132 and 156 mm. Growth rate has been observed to be very fast on floating buoys. A fair number of individuals attains a marketable size of about 60 mm in length in 6 months after initial setting. Influence of the environmental parameters on seed setting and growth rate of the spat has been studied. Length-weight relationship has been expressed as W = 0.00066 x L2.42. Breeding takes place in the species throughout the year as revealed by histological study of the gonads at periodical intervals round the year. Larval frequencies in the environment show maximum abundance in October-November, followed by a minor peak about March. Spat setting takes place very intensively during October-November corresponding with the period of major peak occurrence of the larvae in the waters. The scope for undertaking mussel culture operations in the waters around Goa has been indicated.