In an increasingly urbanized world, biodiversity, and more specifically, birdlife located in urbanized ecosystems, faces several threats. Among these, noise pollution has proven to be one of the most significant, as it affects the effectiveness and efficiency of acoustic communication. We studied the relationship between noise and the diversity and abundance of birds breeding in urban areas in the central region of the Iberian Peninsula (Spain). We analyzed how species diversity and density varied across three levels of noise pollution (high, medium, and low). Species diversity decreased in areas with high noise pollution as compared to sites with medium and low levels of noise. We analyzed the density of the most frequent species found within each category. We identified eight additional noise-tolerant species whose density had significantly increased in environments with high levels of noise (e.g., Blackbird, Eurasian Tree Sparrow, and the Coal Tit). The ten most sensitive species, such as the Common Linnet, House Sparrow, and the European Greenfinch, had significantly decreased densities when the level of noise increased. Identifying the sensitivity (the effect) of urban bird species to acoustic pollution is vital for effective conservation management measures and for the sustainable planning and management of cities.

In an increasingly urbanized world, biodiversity, and more specifically avifauna localised in urbanized ecosystems face several threats. Among them, acoustic pollution has proven to be one of the most important, as it affects the effectiveness and efficiency of acoustic communication. Especially sensitive species are even disappearing due to noise masking. We have studied the effect that noise has on bird distribution in areas with differing levels of urbanization in the central region of the Iberian Peninsula. We analysed how richness, frequency and abundance of species varied along three acoustic pollution levels (high, middle and low). Richness decreased in areas with high acoustic pollution. We identified less sensitive to noise species, which showed no changes in frequency and abundance between environments (such as the house sparrow, the white wagtail and the European robin) or that even increased its abundance in environments with high levels of noise (such as the blackbird, the Eurasian tree sparrow and the coal tit). The more sensitive ones, such as the common linnet, the mistle thrush and the European greenfinch, decreased their distribution when noise increased. Identifying the sensitivity (how it is affected) of urban bird species to acoustic pollution is vital for effective conservation management measures and for the sustainable planning and management of cities.