Effect of cadmium on particle clearence by the Sydney rock oyster, Saccostrea commercialis (I. & R.)

Abstract

Sydney rock oysters, S. commercialis (I. & R.); were exposed to a control and 10. 50 and 100 µg 1^-1 cadmium in a flowing seawater system in the laboratory for 45 days. After this period the rates of particle clearance, assessed by using killed ¹⁴C-labelled Escherichia coli in suspension, were determined for each group of oysters. A small proportion of ¹⁴C-label from the E. coli was recovered from the non-gut tissues of the oyster, suggesting that the oyster digested, and may have derived some energy from, the bacteria. All cadmium- treated oysters displayed reduced efficiency of clearance compared to controls. If this sublethal effect of cadmium occurs in natural populations, oysters could suffer impaired feeding efficiencies with subsequent effects on growth and reproduction.