We examined maximal and ecological performance in Ameiva ameiva on Union Island, St. Vincent and the Grenadines. Maximal sprint speed was correlated positively with lizard body size but not with hind-limb or relative hind-limb length. Lizards in the field used over 85% of maximal capacity when escaping a putative predator, and the proportion of maximal speed used was highly dependent on behavioral context. Mean and median speeds used by adults when moving undisturbed through the habitat were 15.37 ± 2.01 (SE) and 11.41% of maximal speed; and approximately 65% of undisturbed movement is at speeds <15% of maximal capacity. No individual movement exceeded 40% of maximal capacity. Mean and median values for distances moved were 7.88 ± 0.72 (SE) and 8.14 cm, with 91% of distances moved <12 cm and 69.5% <10 cm, demonstrating that undisturbed lizards move through their habitat using short individual movements at low speeds. Similar to other studies on primarily sedentary lizards, actively foraging lizards may experience stronger natural selection on locomotor speed when evading a predator rather than while foraging because these lizards use nearly 90% of their maximal capacity during the former activity.