Contribution of acoustic methods to the study of insectivorous bat diversity in protected areas from northern Venezuela

We present the results of an acoustic survey of aerial insectivorous bats conducted in four protected areas in
northern Venezuela. These areas represent localities where the taxonomic composition of the bat communities
was relatively well known. We conducted field surveys using the Anabat II detector and analysis system. We
compared acoustic inventories with previous lists obtained with conventional sampling methods (principally
mist nets). We identified 30 species acoustically (representing 15 genera of the families Emballonuridae,
Noctilionidae, Mormoopidae, Vespertilionidae, and Molossidae) on the basis of vocal signatures. Nineteen of
these were verified by capture and subsequent recording of released animals; the remainder were identified by
comparison with verified vocalizations from other localities. An additional 11 unidentified but distinct taxa
were recorded and are referred to here as 'sonotypes' (based on similarities in call structure to known species)
representing eight genera of the families Emballonuridae, Vespertilionidae, and Molossidae. The short-term
acoustic surveys nearly equaled or exceeded the known species richness at three ofthe four localities, and added
two to nine species to previous lists from all locations; many of these bats correspond to taxa difficult to detect
with conventional capture methods.