In response to demands for research, captive breeding, and tourism, a semi-captive environment was created for the Philippine tarsiers (Tarsius syrichta) in Corella, Bohol, Philippines. The 7600-m2 enclosure was continuous with the surrounding habitat, and utilized a unique predator control fence design and a lighting system to attract nocturnal insects. During 2 years of observation, the locations of over 500 tarsier sleeping sites were recorded. Tarsiers were found to prefer dense, low-level vegetation in secondary forests, with perching sites averaging 2 m above the ground. Up to 10 tarsiers were observed within the enclosure at one time, which is a high density compared to densities based on home-range estimates for wild tarsiers in the vicinity of the study site. In addition, the tarsiers were observed to be more social than previously reported. Zoo Biol 24:101–109, 2005. © 2005 Wiley-Liss, Inc.