Relative importance of environmental factors in determining physiological differences between two populations of mussels (Mytilus edulis)

Abstract

M. edulis were reciprocally transplanted between 2 environments, the Tamar estuary (southwest England [UK]) and Swansea dock (south Wales [UK]). Physiological and cellular responses of native and transplanted mussels at each site were measured at the beginning (Jan. 1978) and after 7, 16 and 23 wk. Tissue concentrations of some metals (Cd, Cu, Fe, Pb, Zn) and hydrocarbons were determined. Changes in metal and hydrocarbon concentrations in the tissues were complex, and a function of specific contaminant, tissue and time. There were marked physiological differences between the 2 native populations but transplanted mussels acclimatized to their new environments within 2 mo. This suggested that the measured physiological differences (clearance, respiration and excretion rates, absorption efficiency, O:N and scope for growth) were largely determined by environmental rather than genotypic factors.