Avoiding Predation: The Importance of Chemical and Visual Cues in Poison Frog Reproductive Behaviour

Abstract

The detection of biological signals is especially important in predator-prey systems. Anuran amphibians have evolved a remarkable diversity of defense strategies against predators, but the most risk-free is the prevention of a possible danger. This is valid for the protection of offspring as well. The neotropical poison frog Ranitomeya variabilis deposits both eggs and tadpoles in phytotelmata. The exploitation of these small pools is advantageous as it lowers the risk of offspring predation compared to larger water bodies. Nonetheless, there are potential predators in these pools as well. We analysed how the parent frogs avoid conspecific cannibalistic tadpoles and damselfly larvae of the species Microstigma rotundatum. We compared the use of chemical and visual cues and show that R. variabilis avoids conspecific tadpoles for the deposition of its offspring using chemical cues, while visual tadpole models alone were not avoided by the frogs. Damselfly larvae in contrast were avoided when present, but could not be detected by chemical cues alone. We suggest that the invertebrate predators mask their chemical cues, forcing the frogs to use other senses to detect them.