Flight initiation distance of Urosaurus ornatus from the Sierra de Samalayuca, Mexico

In lizards, flight initiation distance (FID), the distance between a prey individual and a predator when escape begins, can be affected by numerous intrinsic and extrinsic factors, including sex, temperature, and level of conspicuousness. Here we report on a study of FID in a population of Ornate Tree Lizards, Urosaurus ornatus, from the Sierra de Samalyuca, Chihuahua, Mexico which are cryptic due to their dorsal coloration blending into their background. Urosaurus ornatus in our study population allowed close approaches (mean FID = 65 cm). Mean FID did not differ between males and females. We also found no effect of body, air, or substrate temperature on FID. The short FID we observed may be related to the cryptic nature of U. ornatus