Gonadal maturation and trace metals in the mangrove oyster Crassostrea corteziensis: seasonal variation

The concentration of nine trace metals Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn. associated with the gonadal and somatic non-gonadal. tissues throughout the reproductive cycle of the oyster Crassostrea corteziensis Hertlein. have been studied. The metal concentration in this oyster exhibited significant seasonal variations. The highest concentrations of Cu, Ni, Pb and Zn occurred in November when the oyster was in the resting phase, while the maximum of Mn was recorded in March when the population was predominantly in gametogenic activity. The elevated values of Cd and Fe were presented in September during the post-spawning phase. Only Mn showed a good positive correlation with the maturation of the organism. This last result suggests that Mn may perform some function during the gonadal maturation or prespawning.