Brazilian Cerrado nocturnal summer soundscape

Abstract

The Brazilian Cerrado is one of the world’s biodiversity hotspots. Our objective was to characterize its nocturnal soundscape. 12 autonomous recorders (SongMeter2 + , Wildlife Acoustics) were deployed in Canastra National Park (MG/Brazil) and recorded five consecutive nights during the rainy season. Using Arbimon II soundscape builder we identified four frequency bands with higher activity levels. The lower band (0.3-1.3 kHz) is acoustically occupied throughout the night. The second band (2.8-3.2 kHz) is highly active around sunset and almost disappears after 10 PM. The third band (3.8-6.6 kHz) splits into two near 9 PM, with the upper limit disappearing after 3 AM. The highest frequency band (9-16 kHz) is the broadest and occupied in all recordings, being comprised by unidentified background noise. Insects (mainly crickets and cicadas) are present in the three superior bands, anura in the two lower bands, and birds in the second and third near dusk and dawn. Characterizing such protected soundscapes is vital for future monitoring and identification of changes in this important Brazilian preserve.