Community-wide consequences of nonconsumptive predator effects on a foundation species

1. Predators can exert nonconsumptive effects (NCEs) on prey, which often take place through prey behavioural adjustments to minimize predation risk. As NCEs are widespread in nature, interest is growing to determine whether NCEs on a prey species can indirectly influence several other species simultaneously, thus leading to changes in community structure.

2. In this study, we investigate whether a predator can exert NCEs on a foundation species and indirectly affect community structure.

3. Through laboratory experiments, we first tested whether the predatory marine snail Acanthina monodon exerts negative NCEs on larviphagy (consumption of pelagic larvae) and phytoplankton filtration rates of the mussel Perumytilus purpuratus, an intertidal foundation species. These hypotheses stem from the notion that mussels may decrease feeding activities in the presence of predator cues to limit detection by predators. Afterwards, a field experiment tested whether the presence of A. monodon ne...