Social learning of predators by tadpoles: does food restriction alter the efficacy of tutors as information sources?

Prey animals often need to learn the identity of unknown predators, and not surprisingly, nearby conspecifics provide a rich source of information about both the identity and risk level posed by unknown predators. Individuals that learn from watching conspecifics that show a weak response to a predator often learn that the predator is a mild threat, while those that observe conspecifics that show a strong response to the predator, learn that the predator is a high-level threat. This means that any factor that influences the intensity of the antipredator response of the tutor can potentially influence the efficacy of information transfer to the observer. We know that food resources influence the activity levels of prey, making them more or less conspicuous to nearby conspecifics. We also know that prey often ignore risk if they have restricted access to food resources. This means that food resources have the potential to dramatically change social learning dynamics. In the present study, we found that tadpoles fed restricted diets had much higher activity levels than those fed ad libitum food resources. Their high activity made them more conspicuous to nearby conspecifics, causing them to be much more efficient as tutors. Our work highlights the dynamic nature of social learning, as information transfer is likely to change considerably from place to place and year to year as resources change through space and time.