Birds adjust their singing activity around airport noise
Scientists from the Max Planck Institute for Ornithology in Seewiesen have determined that birds near Berlin's Tegel airport, one of Europe's largest, start singing significantly earlier in the morning than their counterparts at quieter locations. What's more, they discovered that chaffinches stop singing when the noise from air traffic exceeds a threshold of 78 decibels (A).
Noise pollution caused by humans has been shown to have a negative impact on health and wellbeing - and criticism is frequently directed at the massive noise levels generated by air traffic in particular. However, noise pollution affects not only humans, also the acoustic communication that is so vital to birdlife can be lost in the din. Since the two most important functions of birdsong are territorial defence and the attraction of a mating partner, disturbances by noise can impair their reproductive success.
Scientists from the Max Planck Institute for Ornithology in Seewiesen have been investigating the effects of aircraft noise on the singing behaviour of ten species of songbirds. Berlin-Tegel airport operates between six a.m. and eleven p.m., with take-offs and landings about every two minutes. For this study, the team of behavioural biologists selected the Jungfernheide forest, immediately adjacent to the airport, along with a similarly structured area four kilometres away, the Tegeler forest. To avoid the influence of light pollution on singing activity, the dawn songs of the different species were recorded at locations a sufficient distance from the forest edge and at the same time they measured the noise levels in both areas. This method allowed the team to demonstrate, for the first time, a direct correlation between air traffic noise and changes in birdsong activity.