Traffic noise exposure affects telomere length in nestling house sparrows

International audienceIn a consistently urbanizing world, anthropogenic noise has become almostomnipresent, and there are increasing evidence that high noise levels canhave major impacts on wildlife. While the effects of anthropogenic noiseexposure on adult animals have been widely studied, surprisingly, therehas been little consideration of the effects of noise pollution on developingorganisms. Yet, environmental conditions experienced in early life can havedramatic lifelong consequences for fitness. Here, we experimentally manipulatedthe acoustic environment of free-living house sparrows (Passerdomesticus) breeding in nest boxes. We focused on the impact of such disturbanceon nestlings’ telomere length and fledging success, as telomeres(the protective ends of chromosomes) appear to be a promising predictor oflongevity.We showed that despite the absence of any obvious immediate consequences(growth and fledging success), nestlings reared under traffic noiseexposure exhibited reduced telomere lengths compared with their unexposedneighbours. Although the mechanisms responsible for this effect remain tobe determined, our results provide the first experimental evidence that noisealone can affect a wild vertebrate’s early-life telomere length. This suggeststhat noise exposure may entail important costs for developing organisms