The effects of embryonic experience with predation risk vary across a wave exposure gradient

Abstract

Gradients in environmental stress can alter the ecological effects of predation risk to create variable landscapes of fear that shape prey antipredator responses. Prey obtain information about their risk environment not only from their immediate experiences with predators, but also from their previous experiences, especially if they occur during particularly sensitive windows in ontogeny. Embryonic development is often a key window when an individual's experiences can have lasting effects on behavior and fitness. The propensity of embryonic experiences with predation risk to affect prey performance, however, may vary across gradients of abiotic stress. Using a rocky intertidal system, we explored whether a dominant abiotic stressor—wave exposure—modifies the influence of embryonic experience with predation risk (from the green crab, Carcinus maenas) on prey (the carnivorous snail, Nucella lapillus) traits both at emergence and as one-year-olds exposed to current predation risk. We found that snails from wave-exposed, but not sheltered, populations emerged smaller from development and grew less in the absence of current risk as one-year-olds if they experienced risk as embryos. However, exposure to current predation risk reduced the growth and growth efficiency of one-year-old snails from both wave-exposed and sheltered populations. Our results demonstrate that increased environmental stress can modify predator–prey interactions and enhance prey reliance on early life experiences with predation risk, but that direct exposure to risk later in life can strongly affect prey performance across environmental stress gradients.