On the Nutrition and Metabolism of Zooplankton X. Quantitative Aspects ofCalanus HelgolandicusFeeding as a Carnivore

Abstract
INTRODUCTIONIn an earlier study (Corneret al.1974) the copepodCalanus helgolandicus(Claus) was found to feed actively on nauplii of the barnacleElminius modestusDarwin, one adult female ingesting a maximum daily ration equivalent to 25% of the body nitrogen. The present work, in whichElminiusnauplii have again been used as a diet, extends the earlier study by determining how efficientlyCalanusdigests an animal food. In addition, the methods used have provided information on other aspects of carnivorous feeding byCalanus, including the relationship between food concentration and size of ration ingested as well as gross growth efficiency, i.e. the proportion of ingested food invested in growth.