FACTORS AFFECTING THE ASSIMILATION OF ORGANIC MATTER BY ZOOPLANKTON AND THE QUESTION OF SUPERFLUOUS FEEDING1

Abstract

A temperature increase of 3 to 5C in the range from 2 to 11C had no effect on percentage of assimilation by Calanus hyperboreus feeding on diatoms. Neither age of food culture nor the length of exposure to the food affected utilization. However, food organisms with a low ash content seemed to be more completely assimilated than those with a large amount of ash. Percentage of assimilation was not related to amount of food offered nor to the amount of food ingested by the copepods. Similarly, there was no relationship between the quantity of food available in the sea and percentage of assimilation by the zooplankton community. It is concluded that “superfluous feeding” does not normally occur in nature.