Predation risk in two Patagonian Liolaemus lizards: Similar escape behaviour in different environmental contexts

Abstract

Prey species may assess the risk of being preyed upon and consequently decide adequate antipredator behaviours that increase their probability of survival. Predation risk is expected to increase with predation pressure, and conversely, to decrease with habitat complexity. Additionally, the colour pattern of the prey may also influence predation risk and conspicuous animals may experience higher risk than cryptic ones. Here we studied escape behaviour of Liolaemus kolengh and L. zullyae, two Patagonian lizard species occurring in habitats with different complexity and abundance of predators. Additionally, they exhibit sexual dichromatism with colourful males and cryptic females. We predicted that both species would show similar escape behaviour, with males showing more intense responses than females. In the field, we simulated predation events and registered flight initiation distance (FID) and refuge distance (RD), two escape behaviour variables related to predation risk in lizards. As expected, both species showed similar FID and RD, which may be explained by the combination of high abundance of predators-high complexity at the habitat of L. zullyae, and low abundance of predators-low complexity at the site of L. kolengh, but also by similar availability and use of rocks as refuges by the species. Intra-specifically, sex influenced FID of L. kolengh lizards only when perching on bare ground, with females allowing closer approaches than males, probably related to a lower detectability against this background. We suggest that environmental variables, microhabitat use and intrinsic characteristics, such as coloration and sex may interact to influence predation risk and escape behaviour.