THE INFLUENCE OF TEMPERATURE ON THE SURVIVAL, GROWTH AND RESPIRATION OF CALANUS FINMARCHICUS

¹ From the Biological Laboratories, Harvard University, and the Woods Hole Oceanographic Institution

Laboratory tests on cultures of Calnusin relation to the ecology of this species showed that: (a) removal of the culture dishes from constant low temperature to room temperature for daily periods as great as 120 minutes was not harmful to the copepods; (b) growth was poorer at 3° C. than at 6 to 9° C. but survival is better at the lower temperatures; (c) both growth and survival decreased regularly in passing from experiments conducted in the spring to those in the autumn.

Measurements of the respiration of Calanus using the Winkler method and the Dixon-Haldane respirometer showed that the magnitude of the oxygen requirement for our animals is of the same order as for those tested by Marshall, Nicholls, and Orr, and possibly is higher than previously reported. The discrepancy between the estimated food requirement of Calanus and the average abundance of diatoms therefore still exists but certain possible explanations are discussed.