Space use and phenotypic plasticity in tadpoles under predation risk

Abstract

Food acquisition by most organisms is a complex ecological process that involves benefits and risks, affecting organism development and interspecific interactions. The evaluation of habitat selection, food consumption, and predator avoidance is pivotal for understanding the ecological process affecting life history traits and the role of species on communities and ecosystems. In a microcosm experiment, we evaluated if Rhinella diptycha tadpoles actively choose to forage in habitats with high resource (food) availability and if they avoid such habitats when predators are positively correlated with resource distribution. We also evaluated if behavioral changes under predation risk were associated with specific morphological phenotypes. We observed that tadpoles chose, although not intensely, habitats with high resource availability when predator cues were absent, but they avoided the same habitats when predation cues were present. We also observed an increase in swimming activity and morphological changes in tadpoles exposed to predation risk, especially related to body and tail morphology, which translates into rapid development. Our results suggest that tadpoles assess habitat quality through resource availability and predation risk. Moreover, our results suggest that tadpoles seem to exhibit functionally independent co-specialization of defensive strategies, due to the expression of specific behavioral and morphological phenotypes.