BIOCHEMICAL-COMPOSITION, RESPIRATION RATE AND GONAD DEVELOPMENT IN LATE-STAGE COPEPODITES OF CALANOIDES CARINATUS (KROYER) FROM THE BENGUELA UPWELLING REGION

Biochemical composition, respiration rate and gonad development in CIV s, CVs and adults of Calanoides carinatus in the Benguela upwelling re gion were investigated. The changes of these parameters within each st age were analysed. The surface CV were shown to follow two trends of d evelopment. Those with a small oil sac, low lipid content and well dev eloped gonads seem to moult immediately into adults. Others with a lar ge oil sac, high lipid content and small undeveloped gonads were assum ed to form a diapausing stock descending into deeper layers. A correla tion between biochemical composition, respiration rate, gonad developm ent and oil sac volume was obtained. Copepods with maximum lipid and p rotein content, small undifferentiated gonads and minimum respiration rate seem to be in the initial ''deep'' diapause phase. The size of go nads and respiration rate increased with the lipid expenditure. At the end of diapause, copepods that consumed nearly all of the lipid and s ome of the protein had gonads similar to those of the adults. Diapausi ng CV could moult in the deep layers. However, reproduction is likely to occur only after an ascent into the upper layers when feeding begin s.