Abstract
Greater somatic and gonad production were generally observed in scallops Placopecten magellanicus (Gmelin) from shallow water than in those from deeper water, where temperature and food conditions were often less favourable. Annual variation in total production was attributable to differences in reproductive output rather than somatic growth, since the latter changed little from year to year. Controlled growth with oppurtunistic reproductions may be an appropriate strategy in the variable and unpredictable environment which scallops experience in Newfoundland [Canada].