We used nightly surveys to monitor the status of building-dwelling gecko species on the southern Caribbean island, Curaçao. Two gecko species were detected in 10 counts across five nights from 18 sites. We recorded the nonnative Wood Slave, Hemidactylus mabouia (81%, 369/455 observations), native Dutch Leaf-Toed Gecko, Phyllodactylus martini (11%, 50/455 observations), and unidentified geckos (8%, 36/455 observations) on the island. The Dutch Leaf-Toed Gecko was most common near the forest and rare elsewhere. Wood Slave abundance was not influenced by forest proximity. Wood Slaves commonly perched near lights that provided heat and attracted insect prey. In contrast, the Dutch Leaf-Toed Gecko perched away from lights. Similar to gecko species in Florida, Wood Slaves displaced Dutch Leaf-Toed Geckos. The Dutch Leaf-Toed Gecko was syntopic with the Wood Slave on buildings near the forest when resources were not limiting or if other gecko populations were not self-sustaining. As Wood Slave populations grew, they excluded Dutch Leaf-Toed Geckos, and possibly Antilles Geckos, Gonatodes antillensis, from these buildings. This exclusion adds novel obstacles to the continued survival of the Dutch Leaf-Toed Gecko on Curaçao. A similar situation may be present on Bonaire, and for a congeneric species on Aruba, where the Wood Slave is a more-recent colonist.