Lizard Assemblage Response to a Forest Ecotone in Northeastern Australia: A Synecological Approach

An ecotone between rainforest and wet sclerophyll forest on the western side of the Paluma Range, northeastern Australia, incorporates substantial vegetational change. While the entire ecotone extends over several hundred meters, most of the structural and floristic change occurs at an abrupt vegetation discontinuity only a few meters wide. The aim of this study was to assess the influence of the ecotone on the lizard community. Pitfall traps were used to sample the lizard fauna across the ecotone. Twelve species in five families were captured: Agamidae, Gekkonidae, Pygopodidae, Scincidae, and Varanidae. The abrupt vegetation discontinuity represents a barrier to the distribution of many lizard species, and on this basis it is possible to define closed and open forest 'assemblages'. However, there appears to be no predictive relationship between variation in the habitat and lizard assemblages across the ecotone as a whole. The closed and open forest assemblages seem to be largely artificially defined, representing aggregations of species responding individualistically to different aspects of the habitat.