Discriminate feeding of the calanoid copepod Acartia clausi in mixtures of phytoplankton and inert particles

Adult female Acartia clausi were allowed to feed in the laboratory on each of three algae, the small green alga Dunaliella tertiolecta , the diatoms Thalassiosira decipiens and T. nordenskioldii , singly or in mixtures with polystyrene beads. The results suggest that beads are ingested by chance in feeding bouts on T. nordenskioldii . The bead interference on the ingestion rate on cells was observed in the experiments with D. tertiolecta and T. decipiens , but not with T. nordenskioldii .