Variations in the correlation of body size with concentrations of Cu and Ag in the bivalve Macoma balthica

The relationship between body size and concentrations of Cu and Ag varied from strongly positive to strongly negative in four populations of the bivalve Macoma balthica in San Francisco Bay. The correlations appeared to be influenced by the degree of enrichment in tissues, size-dependent differences and seasonal variations in growth rate, and size-dependent differences in uptake rates. The use of benthic indicator organisms to assess metal contamination requires understanding the relationship between metal concentration and body size at least within each population, and in some cases within each sample from each population.