Pacific oyster spat (Crassostrea gigas Thunberg) transferred from the Tamar Estuary to two growing areas in southern Tasmania were monitored for their metal contents over one growing season (1974–1975). Oysters at Pipeclay Lagoon were grown with stick and tray culture while those at Dart Island were cultured with the longline technique. Metal content of the oysters increased with time and the trend was similar to the weight growth curves. Mean dry weights of oysters increased from 0.07 to 1.19 g at Pipeclay Lagoon and from 0.25 to 1.47 g at Dart Island. Metal contents (μg) increased at each site, respectively: Fe 57 to 326; 91 to 446; Zn 259 to 6 555; 755 to 5 335; Cd 1.5 to 13.3; 1.9 to 16.3; Cu 26 to 142; 9 to 116; Pb 1.9 to 11.9; 0.6 to 3.8. Concentration curves generally showed a downward trend with time. The relationships of metal concentrations with weight did not differ from sample to sample at a site nor did they differ at one site compared with the other. The only exception was lead, which showed no relationship of concentration with weight at Pipeclay Lagoon and a negative one at Dart Island. It is postulated that higher winter concentrations of metals in the oysters were linked with greater solubility of metal ions in lower salinity water.