Directional escape strategy by the striped plateau lizard (Sceloporus virgatus): turning to direct escape away from predators at variable escape angles

Abstract

A prey’s orientation to a predator’s approach path affects risk of fleeing straight ahead. By turning to flee closer to straight away from the predator before fleeing, prey can reduce risk. Laboratory studies suggest that escape angles should lead away from predators and be unpredictable. I studied orientation, turn, and escape angles and in a study of striped plateau lizards,Sceloporus virgatus. Lizards fled away from a predator, but often not straight away. Escape angles were variable and bimodally distributed: one mode was straight away for distancing prey from predator and one was near 90°, which maintains ability to monitor the predator or requires turning by the predator. Turn angles increased as orientation shifted toward the predator. Escape angle was closer to straight away when turn angle was larger, but turning did not fully compensate for degree of orientation toward the predator. Directional escape strategies of diverse prey are compared.