Abstract

• The study on the gonad development and condition index of green mussel, Perna viridis from Ye Estuary was conducted from January to December 2017. Sample collection was made by the help of local mussel collector during low tide. Ripe gonads were in good numbers from January and March and peak spawning ones were observed from April to July.The occurrence of spawning and partially spent specimens of both sexes recorded from April to October indicated that spawning took place during a prolonged period. P. viridis exhibited year-round gametogenesis and monsoon spawning. Surface water temperature at Ye estuary varied between 27.60°C in August and 32.00°C in March. CIshwt and CIcommercial values were high in June and low in July and December. High CI values in June may be due to ripe gonad states and food available from the river runoff. The low CI value in July coincides with the peak spawning stages of male and female mussels. The study indicated that there is obvious seasonal variation in the mussel condition and gonad maturation.