Acoustic and temporal birdsong measurements

Sound recordings used for this study were recorded by MCK in January and March of 2017 using four autonomous recording units (ARU) (SongMeter SM3, Wildlife Acoustics Inc., Concord, MA, USA) deployed across a "listening post" in Aleixo Valley and another in Santa Marta Valley(20°28'46.49" S, 41°50'25.00" W and 20°29'25.74"S, 41°44'21.55"W). Each listening post comprised of two SongMeters fixed 1.8 m above ground, each attached to two microphones, facing opposite directions and thus recording in the four cardinal directions (Figure 2). Recordings were sampled at 44.1 kHz and 16 bits per second and recorded in 1-hour segments. A high-pass filter was set at 220 Hz to filter out wind and river noise. Recordings from the two SongMeters at each post were time-synchronized using Garmin GPS’s to triangulate the sound source. Three hours of recording from 0800 to 1100 on three consecutive days were used from each site to investigate the singing avian communities. The nine hours of recording taken from each study site combined for a total of 18 hours of recording for this study. Analysis was carried out in Raven Pro and R Studio.