Predation risk suppresses mating success and offspring production in the coastal marine copepod, Eurytemora herdmani

We investigated the effects of a common mysid predator, Neomysis americana on the mating success of an estuarine copepod, Eurytemora herdmani. The presence of a mysid predator, or only a predator cue, reduced copulation frequency and spermatophore transfer success of E. herdmani, and led to a substantial decrease in E. herdmani nauplius production. Thus, mysid predators can influence copepod population growth through nonconsumptive processes by reducing the frequency and success of mating events. This highlights the need to look beyond population-level demographic factors (i.e., sex ratio and population density) and consider community-level ecological factors (such as predation risk) when modeling population growth rates of prey species critical to marine food webs.