Behavioural responses to predator chemical cues and local variation in antipredator performance in Rana temporaria tadpoles

Antipredator behaviour is an important factor influencing survival probability of prey animals, and it may evolve rapidly as a response to changes in predator regime. I studied antipredator behaviour of common frog ( Rana temporaria ) tadpoles from three populations that differ in predator regimes. In the first experiment, tadpoles obtained from four natural matings in each population were subjected to chemical cues from either European perch ( Perca fluviatilis ) or from larvae of the dragonfly Aeshna juncea . Tadpoles decreased their activity in response to both predators, but the spatial behaviour of tadpoles differed between the two predator treatments. In general, there were no differences in behaviours among the populations, but in three out of four studied behaviours there were differences between parentages within the populations suggesting that these behaviours may be genetically determined. The lack of a significant Predator×Population interaction suggests no differences in plastic antipredator behaviour among the populations, while the lack of significant Predator×Parentage interaction suggests no genetic variance within the populations for plastic antipredator behaviour. In the second experiment, tadpoles from the three populations were exposed to predation by a free-ranging A. juncea . In line with the first experiment, there were no differences in survival rate between the populations. R. temporaria tadpoles seem to rely heavily on plastic antipredator behaviour as their main response to predator chemical cues. There was very little indication of local behavioural differentiation and the possible reasons for the lack of divergence among populations are discussed.