Temporal variability, threat sensitivity and conflicting information about the nature of risk: understanding the dynamics of tadpole antipredator behaviour

The importance of temporal variability in predation risk has recently come to the forefront of research examining the behavioural ecology of predator-prey relationships. Temporal variability has been known to drive patterns of behavioural responses associated with foraging, reproduction and territorial defence of prey animals. We investigated whether larval woodfrog, Rana sylvatica, tadpoles learn to adjust the intensity of their antipredator responses to match (1) the temporal patterns of risk they experience throughout the day and (2) the risk level of a predator. We also examined how tadpoles incorporate temporally conflicting information on the risk posed by the predators. Our results indicate that tadpoles show dynamic adjustments in their behaviour, adjusting their response to predators according to the level of threat associated with the predator and the time of day at which the predator represents the most significant threat. Moreover, tadpoles responded to conflicting information by adjusting their response intensity depending on the nature of the change in vulnerability (whether the risk increased or decreased) and the time that the conflicting information was experienced (whether it was recent or old information). We discuss our results within the context of predator predictability in natural systems and game theory approaches to the behavioural response race between predator and prey. (C) 2009 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.