COS 73-3 - Mapping the impact of road traffic noise on animal behaviors in non-urban areas

Abstract: Roads have been shown to have many ecological impacts, but the impacts of road traffic noise are underappreciated. Studies that have examined noise impacts, show that traffic noise substantially alter animal behavior, leading to reduced reproduction success and survival at vast distances. Although mapping noise propagation is a commonly employed approach, depicting and quantifying the areas where noise is likely to exert ecological effects is much less practiced.

We examined the potential impact range of traffic noise on wildlife behavior. To do so, we reviewed existing literature and identified ranges of the impact of traffic noise on different animal behaviors across several taxonomic groups (i.e., birds, mammals, amphibians, and reptiles). Based on these ranges, we quantified and mapped the non-urban areas in Israel where animals are expected to suffer from noise effects, with an emphasis on sensitive habitats and nature reserves.

Within 200 meters from roads, noise negatively affects hunting efficiency, drastically changes vocal communication properties, and limits habitat selection. Over a third of the non-urban areas in Israel are exposed to noise effects in this range, a high value compared to other countries. In addition, about a quarter of the protected areas are within this range. Of the various habitats, wetlands, which are among the most sensitive to noise exposure, are highly exposed. A range of 1,500 meters from roads, where most of the impact on habitat selection in breeding birds is expected, represents 76% of the open areas in Israel and 63% of the protected areas.

We conclude that, for many species, the non-urban and protected areas in Israel are not a safe refuge from the deleterious effects of roads. Following our study, we approached governmental offices to promote the use of noise mitigation tools, originally developed for urban environments, also next to ecological hotspots. Our examination of the adverse effects of road traffic noise pollution on animal behaviors, including calculating the ranges of these impacts, can be used in other parts of the world. We recommend mapping noise sources as a basis for the sustainable placement of noise-emitting infrastructures.