Is mating of copepods associated with increased risk of predation?
In laboratory experiments, we tested whether the cyclopoid copepod Cyclops vicinus is more vulnerable to predation by juvenile (young-of-the-year) roach (Rutilus rutilus) and/or larvae of the phantom midge Chaoborus flavicans during mating than individual adult copepods of the same species. We also tested whether C.vicinus avoided mating, displayed shorter mating times and/or lower activity when a predator (Chaoborus) was present, or when exposed to water in which predators (Chaoborus) were previously held. Fish ate the same quantity of pairs in copulation and individual egg-bearing females but significantly fewer females without eggs. Chaoborus ate similar quantities of pairs and females but fewer males. Pairs in copulation and egg-bearing females were detected earlier by fish than individual non-ovigerous females or males, and pairs in copulation were captured most easily by fish. Cyclops vicinus mated less often when Chaoborus larvae were present than in water in which Chaoborus was
