Biophony in a noisy tropical urban forest fragment

Anthropogenic noise, which is part of an urban soundscape, can negatively affect the behaviour of wild animals. Here we investigated how biophony (animal sounds) was affected by noise in an urban Brazilian forest frag-ment. Our hypothesis was that noise and biophony would differ between the border and the centre of the forest fragment (i.e., lower biophony predicted in noisy areas). Two passive acoustic monitoring devices were used to record soundscapes one week per month, 24 hour per day, from May to July 2012. The Acoustic Complexity Index (ACI) was used to quantify biophony and the Power Spectral Density (PSD) to quantify urban noise. PSD and ACI were higher on the border than in the centre of the fragment. PSD was lower in July, while the ACI did not significantly vary between months. Noise levels were also higher on the border. Conversely, potential spe-cies richness was higher in the centre of the forest fragment. Higher biophony at noisy sites can be interpreted as behavioural responses of species for communicating in noisy areas. Alternatively, they could be the result of species segregation by degree of vocal plasticity or due to differences in composition of communities

Biofonía en un ruidoso fragmento de bosque urbano tropical

Anthropogenic noise, which is part of an urban soundscape, can negatively affect the behaviour of wild animals. Here we investigated how biophony (animal sounds) was affected by noise in an urban Brazilian forest fragment. Our hypothesis was that noise and biophony would differ between the border and the centre of the forest fragment (i.e., lower biophony predicted in noisy areas). Two passive acoustic monitoring devices were used to record soundscapes one week per month, 24 hour per day, from May to July 2012. The Acoustic Complexity Index (ACI) was used to quantify biophony and the Power Spectral Density (PSD) to quantify urban noise. PSD and ACI were higher on the border than in the centre of the fragment. PSD was lower in July, while the ACI did not significantly vary between months. Noise levels were also higher on the border. Conversely, potential species richness was higher in the centre of the forest fragment. Higher biophony at noisy sites can be interpreted as behavioural responses of species for communicating in noisy areas. Alternatively, they could be the result of species segregation by degree of vocal plasticity or due to differences in composition of communities.El ruido antropogénico, que forma parte de un paisaje sonoro urbano, puede afectar negativamente el comportamiento de los animales En este estudio investigamos cómo la biofonía (sonidos de animales) se vió afectada por el ruido antropogénico en un fragmento de bosque urbano brasileño. Nuestra hipótesis es que el ruido y la biofonía difiren entre el borde y el centro del fragmento de bosque (es decir, una menor biofonía en áreas ruidosas). Se usaron dos dispositivos de monitoreo acústico pasivo para grabar paisajes sonoros una semana al mes, 24 horas al día, de mayo a julio de 2012. El índice de complejidad acústica (ACI) se usó para cuantificar la biofonía y la densidad espectral de potencia (PSD) para cuantificar el ruido urbano. Se obtucieron mayores valores de PSD y ACI en el borde que en el centro del fragmento. La PSD fue menor en julio, mientras que el ACI no varió significativamente entre meses. Los niveles de ruido también fueron más altos en el borde, mientras que la riqueza potencial de especies fue mayor en el centro del fragmento de bosque. Una mayor biofonía en áreas ruidosas puede ser interpretada como el efecto de respuestas conductuales de las especies con el fin de establecer una comunicación efectiva. Alternativamente, podrían ser el resultado de la segregación de especies por grado de plasticidad vocal o debido a diferencias en la composición de las comunidades

Tooting the Latin American horn: advances in the scholarship of ecoacoustics and soundscape ecology is occurring with vigor

Soundscape ecology (Pijanowski et al., 2011a,b; Pijanowski & Farina, 2011), ecoacoustics (Sueur & Farina, 2015) and bioacoustics (Laiolo, 2010; Aide et al., 2013) Soundscape ecology (Pijanowski et al., 2011a,b; Pijanowski & Farina, 2011), ecoacoustics (Sueur & Farina, 2015) and bioacoustics (Laiolo, 2010; Aide et al., 2013) have witnessed an explosion of work over the last decade due to the advances in passive acoustic recorders, new conceptual frameworks that integrate the study of sound into environmental change research, abilities to store and analyze massive data, and the growing need to understand how the rapid declines in species richness and abundances can be addressed with intervention policies at the landscape level. Also of note are the tremendous contributions to these acoustic-based fields of research that are occurring from all across the global academy, with advances being made by researchers working in just about every continent and country. The contributions from Latin America are impressive and play an important and unique role in our understanding of how a variety of sound sources – from biological organisms (i.e., the biophonies), to the geophysical world (i.e., geophonies) and those from humans (i.e., anthrophonies or technophonies) – are used to assess how important Latin American ecosystems are being altered. The purpose of this paper is to provide a summary of the multi-faceted work being conducted in Latin America as represented in the exceptional papers of this special issue on ecoacoustics and soundscape ecology, placing these in the context of the growing scholarship in these acoustics-based areas of study