Tree Buttress Microhabitat Utilization by a Neotropical Leaf-Litter Herpetofauna

Abstract

Microhabitat specialization has been implicated as one factor allowing the maintenance of high species diversity in tropical ecosystems.  We assessed the importance of tree buttresses as a microhabitat for the leaf litter herpetofauna in a tropical wet forest in Costa Rica by making comparisons of species richness and abundance between pairs of 4 x 4 m leaf litter quadrats.  One quadrat in each pair contained a central buttressed tree and the other did not.  Both abundance and species richness of the herpetofauna were much greater in plots containing buttressed trees; higher species richness in buttress plots was attributed solely to greater abundance in these plots.  Buttress and non-buttress plots contained a similar species composition, and we found evidence of specialization on tree buttresses by a single species, the scincid lizard Sphenomorphus cherriei.  Our results indicate that the microhabitat provided by tree buttresses forms a site of generalized high abundance for the leaf litter herpetofauna, and may contribute to localized high abundance of at least one species.