Laboratory and field experiments on the feeding ecology of the cyclopoid copepod, Mesocyclops edax

SUMMARY. 1. Gut contents of Mesocyclops edax consisted of rotifers. cladocerans, copepods and algae, the importance of each varying seasonally. 2. Functional response experiments using two soft‐bodied rotifers as prey showed an increase in ingestion rate with increasing prey density up to a threshold, followed by a decline. 3. Enclosure experiments with natural assemblages of prey from two lakes indicated that Mesocyclops edax is a selective feeder and may ingest fifty or more prey per predator per day, accounting for up to 17% of the standing crop of its preferred prey species per day in nature.