Parental effects and individual experience of predation risk informs growth and the energy budget of prey

Abstract

Abstract Predation risk imposes considerable pressure on the growth and energy budget of prey. Prey must respond to both small-scale fluctuations in predation risk as well as adapting to more persistent larger-scale differences in predatory threat experienced by separate populations. These more persistent pressures, potentially result in the development of antipredator responses of offspring, through parental effects. To understand how parental effects may modify the responses of prey to predation risk, we reared the offspring of intertidal gastropods (Nucella lapillus), collected from different wave exposure environments where predation pressures differ. Offspring were reared under various patterns of predatory risk through the period of juvenile development. Shell length, the relative investment in defensive shell structure and long-term energetics of offspring were then analysed to determine the influence of parental habitat and direct predatory threat. As anticipated, lower growth rates were generally associated with extended exposure to predation risk, although parental habitat was able to mitigate these impacts in an adaptive manner. By contrast, the role played by parental habitat in modifying the energetic responses of prey was less clear. Despite differences in the responses of individual energetic fractions to risk, our results showed no long-term impact on the energy status of Nucella offspring. Finally, individual experience of risk was not modified by parental habitat in determining the relative investment in defensive structures. Overall, we demonstrated that parental effects may combine with individual experience of risk, to influence energy storage and define important growth and defence metrics of offspring from different populations.