between 0500 to 0700 h, 1000 to 1200 h, and from 1800 to 2200 h, totaling
528 analyzed minutes. The above time slots were chosen so that
the following were included: the dawn and dusk choruses of birds and
themidday and night activity of insects. Itwas not possible to determine
species abundance aurally owing to the huge number of calls recorded.
Insect sounds and bat social calls were classified as soundmorphs (different
sound emissions or codas). This procedure was essential in
order to identify potential species because the biodiversity in the Atlantic
forest is so high that it is impossible to identify every species by aural
census; additionally, there is a chance that some species recorded are
not yet taxonomically classified.
From the recordings, the bandwidth, minimum and maximum frequencies
of bird vocalizations and insect stridulations(most representative
groups) thatwere identified only at one of the two sites (close or far
from the mine) were extracted to compare the acoustic niche occupation
of the singing community between the two sites.