Application of some growth models to the black scallop,Chlamys varia (L.) from lanveoc,bay of brest

Linear day degree models were constructed, separately for each age group of the black scallop, Chlamys varia (L.) from Lanveoc, Bay of Brest and were found to be capable of predicting growth in terms of increase in shell height. Instantaneous growth rates, computed for evry month of the year, decreased with increase in age and showed minimal values in winter months. Q₁₀ values, calculated from instantaneous growth rates, demonstrated that growth did not depend upon temperature alone. Empirical models developed using temperature, food, and gonad index as independent variables, showed that both temperature and food together formed decisive factors for growth rates. The growth of the dry body tissue of the black scallop was also calculated for each age group and showed an obvious seasonal fluctuation.