Effects of Anthropogenic Light and Noise on Anti-Predator Behaviour and Reproductive Success of an Urban Nesting Passerine

Abstract

Species inhabiting urbanized habitats are continually facing challenges as urbanization intensifies. For urban birds, noise pollution may affect acoustic communication, and light pollution may affect circadian rhythms, yet very little research has been conducted in these areas. I investigated the effects of noise and light pollution on daily nest survival and anti-predator behaviour of American robins (Turdus migratorius) Toronto, ON Canada over 2 summers by monitoring nests and by using an observational and experimental approach. Anti-predator behaviours were influenced by light and noise pollution, but nest survival was unaffected. Higher levels of anthropogenic light and noise had no effect on nest survival; even experimentally increasing light levels at nests had no effect. Higher light and noise pollution did increase the frequency of anti-predator behaviours by nesting birds. Lastly, in areas of higher noise pollution robins were less likely to respond to experimental predator calls.