This bundle of 3 CD contains two types of recordings: (1) Calls of a particular species, for which we usually selected recordings of single specimens, with highest recording quality available, and most typical calls. The terms ''call'' or ''calls'' generally refer to advertisement calls. If release calls or distress calls are described, it is explicitely mentioned. (2) Soundscapes, which were selected to give a general impression of the variety of sounds in Madagascan rainforests. Many of them are mixed choruses of several species, sometimes the recorded species could not be reliably identified, and some soundscapes include vocalizations of other Madagascan animals. Temperature data refer to air temperature unless otherwise stated.

The booklet (44 pages) provides information on the authors, localities, dates and temperature conditions for the recordings on the three CDs, and on the natural history and calling behaviour of the frog species recorded. More detailed data on the species can be found in an updated version of the “Fieldguide to the Amphibians and Reptiles of Madagascar” by F. Glaw and M. Vences that will be published in 2006.

Except when otherwise indicated the species recordings included have only been lightly processed digitally, preserving both the temporal and spectral characteristics of the calls. When filtering was applied it was used to eliminate background noise, after checking that filtering did not interfere with the spectral characteristics of the call. The frequency limits and characteristics of the parametric filters (highpass, lowpass, and bandpass) are explicitly stated in the text. Filtering software used was Spectral Filter (SoundFront FX for SoundMaker, www.Riccisoft.com). All recordings from a given species are included on the same CD Track unless advertisement calls from different populations are clearly different. When more than one recording was selected within a track, these are separated by 0.75 seconds of silence and organized in subsequent Cuts which are addressed individually in the written comments. Soundscapes may have been modified more intensely to improve the aesthetic value of the audition (cutting or filtering noisy sections etc.) but tracks have never been mixed: all the choruses heard are natural.

This collection is the result of the collaboration of 15 scientists from seven countries co-edited by the world leading authorities in Malagasy Herpetofauna: Prof Dr. Miguel Vences (Division of Evolutionary Biology, Zoological Institute,Technical University of Braunschweig, Germany) and Dr. Frank Glaw (Zoologische Staatssammlung, München, Germany) in collaboration with Dr. Rafael Márquez, founder and Director of the Animal Sound Library of the National Museum of Natural Sciences (CSIC) of Madrid (Spain) a leading institution in promoting the edition of anuran sound guides worldwide.