Comparative escape behavior of four species of Mexican phrynosomatid lizards

Several internal and external factors can influence escape behavior in lizards. We studied the escape behavior of four Phrynosomatid lizards (Urosaurus bicarinatus, Sceloporus gadoviae, S, anahuacus, and S. mucronatus) from Mexico. Each species exhibited a unique combination of escape behaviors. Urosaurus bicarinatus had short approach and flight distances, and used squirreling (running to opposite side of tree or rock) when approached. Sceloporus gadoviae had a short approach distance, a large flight distance, and often used squirreling. Sceloporus anahuacus had a short approach distance, an intermediate flight distance, and typically fled under a nearby rock. Sceloporus mucronatus had large approach and flight distances, and ran under large rocks when approached. Males and females of all species did not differ in approach or flight distance. Reproductive status had no effect on approach or flight distances for the species where reproductive status was assessable (S. anahuacus and S. mucronatus). Body size did not influence either approach distance or flight distance for any species. Temperature had little effect on flight and approach distance except for S. gadoviae where warmer lizards tended to have shorter approach distances. Lizards that escaped capture used warmer sites than those that did not escape. We caught > 75% of U. bicarinatus and S. gadoviae, 67% of S. anahuacus, and only 38% of S. mucronatus. Catchability appeared to be influenced by temperature (intraspecifically) and by approach and flight distance (interspecifically). While escape behavior of these lizards was generally not affected by internal or external conditions, our results suggest the ability of lizards to escape capture potentially depends on internal and external conditions (e.g., temperature).