Spatial and temporal distribution of breeding anurans in streams in southeastern Brazil

Anuran communities were studied at eight permanent forest streams located in a preserved site in southeastern Brazil, from August 2003 to October 2004. Nineteen species were recorded in six families: Bufonidae ( two), Centrolenidae ( one), Cycloramphidae ( one), Hylidae ( 12), Hylodidae ( two), and Leiuperidae ( one). Twelve species exhibited calling activities during the study period and 10 of these were assumed to be reproductively active. The number of species present in streams was negatively related to stream volume. The composition of anuran assemblages was related to stream volume and structural complexity of the streamside habitat. Levels of dissimilarity between anuran communities from different streams were not related to the geographical distance separating these streams. Rainfall and mean monthly temperatures were not related to anuran species diversity per month, which may be due to forested sites providing appropriate conditions for reproduction for many species year- round and favouring anuran species with long breeding periods. The results obtained indicate that streams of varied sizes, as well as streamside habitats, should be preserved in order to maintain anuran diversity.