Abstract
The behavior of three species of nocturnal Texas geckos, Hemidactylus turcicus. Cyrtopodion scabrum, and Coleonyx brevis, was studied in an indoor laboratory and an outdoor enclosure complex to assess the behavioral I interactions that may affect use of habitat space. H. turcicus and Cyrtopodion scabrum, both of which are introduced, occur syntopically in Galveston, and may be interacting aggressively. The third species is a native Texas gecko, whose continued success might be jeopardized should the ranges of the two introduced species extend westward. For the two introduced species, frequencies of interspecific interactions were greater than in I intraspecific trials. Hemidactylus turcicus was more active in patrolling and tongue flicks than Cyrtopodion scabrum, although frequencies of aggressive behaviors did not differ, Coleonyx brevis did not interact aggressively with either of the introduced geckos, or with conspecifics. Outdoor enclosure trials were conducted to assess the perch choice of each species with and without the presence of the other species. Perch substrate choices varied among the three species of geckos while segregated by species. Hemidactylus turcicus preferred vertical walls, Cyrtopodion scabrum preferred rocks, and Coleonyx brevis preferred ground perches. The distribution of perch choices for visible H. turcicus and Cyrtopodion scabrum remained the same in mixed species trials, however, the proportion of individuals not visible increased for each species. The distribution of perch choices for Coleonyx brevis was not changed by the presence of the other two species. Perch heights varied among the species while segregated and decreased significantly in mixed trials. Directional exposure preference differed between the two introduced species when segregated, but not when mixed. Mean minimum distance moved in a 24-hour interval did not vary among species...
Vaughan, Ramah Kathryn (1991). Competitive interference for habitat space among three species of Texas geckos. Texas A&M University. Texas A&M University. Libraries. Available electronically from
https : / /hdl .handle .net /1969 .1 /DISSERTATIONS -1277051.