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The sound produced by human-made machinery (technophony) is known to exert negative effects on animal communication and well-being. Mining is an important economic activity in Brazil, which is often conducted close to forested areas and produces a diffuse noise. In this study, the impact of such noise on biophony (biological sounds) was investigated by characterizing and comparing the soundscapes of two different sites (close versus distant from an open-cast mine) in the same Atlantic forest fragment, matched for habitat type, in Southeast Brazil. Six automated recorders were installed at each site and were programmed to record continuously during seven consecutive days every two months between October 2012 and August 2013. Technophony and biophony values were derived from power spectra and the Acoustic Complexity Index (ACI). Mann–Whitney U tests demonstrated that the biophony exhibited a switch in daily dynamics, resulting in a statistically higher biophony during the day at the site close to the mine and a higher biophony during the night at the site far from the mine. Potential species richness was found to be higher at the site that was distant from the mine. The species composition and spectral characteristics of the calls were also found to differ between the two sites. These results provide the first investigation of potential disturbances caused by mining noise on biophony, demonstrating that it can cause alterations in the temporal dynamics and daily patterns of animal sounds, which are symptoms of altered behaviors or variations in community-species composition. These findings suggest remarkable insights that should be taken into consideration in the regulating of the use of natural areas for mining. [ABSTRACT FROM AUTHOR]

Abstract: Resource extraction is increasingly affecting protected areas worldwide. However, aside from studies on logging, limited information is available about the effect this has on wildlife, which may be of great consequence, especially when endangered species could be affected. Specifically, the effect of intense human-induced noise during oil exploration on wildlife is poorly understood. We explore the effect of seismic oil exploration on large mammal distribution in an 80km2 area of Loango National Park, Gabon. Following the ecological theory of habitat disturbance, we predicted that changes in habitat use in response to noise disturbance would scale with the body/home range size of each species examined. Our study was conducted over six months before, during and after low-impact seismic operations. We recorded counts along transects of indirect signs of elephants (Loxondota africana cyclotis), chimpanzees (Pan troglodytes troglodytes), gorillas (Gorilla gorilla gorilla), duikers (Cephalophus spp.), and the vocalizations of five monkey species (Cercocebus torquatus, Cercopithecus cephus, C. nictitans, C. pogonias and Lophocebus albigena) and modeled seismic impact over different spatial scales (small, intermediate and large). We found that elephants avoided seismic activity on all three spatial scales, apes avoided on the intermediate and small scales, and there was no effect for duikers and monkeys. We conclude that low-impact seismic operations can cause considerable temporary habitat loss for species with large ranges and suggest that the impact on those endangered species can be minimized by adequately spacing seismic lines and activity in space and time to enable species to move away from the progressive noise disruption. [Copyright &y& Elsevier]