Predicting micro thermal habitat of lizards in a dynamic thermal environment

Abstract

Understanding behavioural thermoregulation and its consequences is a central topic in ecology. In this study, a spatial explicit model was developed to simulate the movement and thermal habitat use of lizards in a controlled environment. The model incorporates a lizard's transient body temperatures with a cellular automaton (CA) algorithm and links the physiology knowledge of the animal with the spatial utilization of its microhabitat. The model assumed that a lizard tries to maintain its preferred body temperature in a dynamic thermal environment by continuously selecting positions with different thermal conditions. The sequence of chosen positions formed a chain defining the individual's path, to be later aggregated into a map of thermal habitat use. An experiment was designed to test the model. An ocellated lizard (Timon lepidus) was kept in a terrarium with controlled dynamic thermal environment, and the thermal environment as well as the movement of the lizard were recorded by a variety of sensors. The model was tested to predict the spatial utilization of a lizard's thermal habitat in the terrarium based on three categories: high, moderate and low occupancy. The simulated results were compared with observations from the animal experiment. The predicted overall pattern of the micro-habitat occupancy of the lizard within 4 days matched the observation, at an overall accuracy of 75.7%. The results suggest that thermal habitat use by lizards in a controlled environment may be predicted by the integrated model of the lizard's body temperature and the CA algorithm.