Passive bioacoustic monitoring as a method to investigate noise pollution in urban parks

The acoustic landscape of a place is formed by biophony, anthropophony and geophony. Biophony comprises the sounds produced by living beings, mainly animals during their communications; geophony consists of the sounds of the geophysical environment, like a river, the rain and waterfalls. In this case study, we evaluated the effectiveness of passive bioacoustic monitoring in detecting anthropogenic pollution in an urban park in Belo Horizonte, Brazil. We used the Song Meter recorder model SM2+ from the Wildlife Acoustics, the recorders were configured to receive sounds of up to 20 Hz. Each recorder was fixed in trees 1.5 m above the ground and 2 microphones were used in each of them. The collected data were submitted to the Generalized Linear Model Test (GLMM), which resulted in a strong influence of anthropic noises on the birds' vocalization. Our results demonstrate the effectiveness of the method and point to the need for the development of public policies to mitigate the effects of noise pollution in urban parks.