Escape Tactics Used by Blanched Lesser Earless Lizards (Holbrookia maculata)

Successful escapes depend on many factors, including predator type and habitat characteristics. Examining escape usually entails directly pursuing an individual and then measuring flight initiation distance (FID), but the effect of prolonged pursuit has not been well studied. We examined escape sequences by blanched adult lesser earless lizards (Holbrookia maculata) in the Salt Basin Dunes (SBDs), testing the hypothesis that escape success and sequences would vary with sex and vegetation use. Their coloration is an adaptation to their sparsely vegetated white sand habitat. To evaluate escape behavior, we followed an individual directly until it disappeared (=successful escape), stopped moving, or 2 min elapsed. We recorded trial habitat (at the start and throughout), time to trial end, FID, length of moves, and total distance moved. FID varied with starting habitat—lizards beginning trials on exposed wood had the longest FID. The sexes differed in their move lengths: females made more short moves, while males made more long moves. The most important plant was sage (Artemisia filifolia), which was occupied at the start of 39% of trials, while 71% of trials ended in sage, and larger sage bushes supported longer escape sequences. Our study highlights the importance of vegetation for refuge and emphasizes the crucial role of the dune-plant landscape to lesser earless lizards.