RAIN-FOREST FROGS OF THE AUSTRALIAN WET TROPICS - GUILD CLASSIFICATION AND THE ECOLOGICAL SIMILARITY OF DECLINING SPECIES

Rainforest frogs are classified into nine ecological guilds based on f eatures of reproduction, habitat use, temporal activity, microhabitat and body size. The largest ecological differences are between the micr ohylid frogs and the rest of the frog species. Within the non-microhyl ids, there are two primary groups consisting of (i) regionally endemic rainforest specialists, and (ii) a more ecologically diverse group of species that are less specialized in their habitat requirements. Most of the regionally endemic rainforest specialists, which includes spec ies in three ecological guilds, have declined or gone missing in recen t years. Multivariate analyses of the ecological characteristics of th ese species show that it is not a single characteristic that isolates those species that have declined from those which have not. The guilds that have undergone significant population declines in the Wet Tropic s are all characterized by the combination of low fecundity, a high de gree of habitat specialization and reproduction in flowing streams. Th ese results have important implications for the determination of the c ausal factors in the unexplained global decline of many amphibian spec ies.