Seasonal growth of juvenile oysters (Crassostrea gigas) kept in an intensive upwelling system was studied from 1984 to 1986 in 60 to 90-day growth experiments. Saline ground water was used to produce Skeletonema costatum which was injected as food into the water supplying the upwelling system. Oyster density, water flow, phytoplankton concentration, temperature and frequency of food addition were controlled. Oyster growth was analysed with multidimensional contingency tables and correspondence analysis. The factors, in order of decreasing influence on growth, were temperature, food concentration and oyster density. A rearing strategy was deduced from the growth analysis for summer and winter. In summer, the density of 120,000 oysters/m2, the flow rate of... |