Effects of anthropogenic noise and light on the vocal and spatial behaviour of birds

Abstract

Understanding how anthropogenic disturbance affects animal behaviour is challenging because observational studies often involve co-occurring disturbances (e.g., noise, lighting, and roadways), and laboratory experiments often lack ecological validity. During the 2016 and 2017 avian breeding seasons, I tested the effects of anthropogenic noise and light on the singing and spatial behaviour of birds. I independently manipulated the presence of anthropogenic noise and light at 110 sites in an otherwise undisturbed boreal forest in Labrador, Canada. Each stimulus was surrounded by a microphone array that recorded and localized singing birds throughout the stimulus presentation. Results show that noise attracts birds, but that light and the interaction between noise and light have little or no effect. None of the treatments affected when birds began singing. My study provides some of the first experimental evidence of the independent and combined effects of noise and light on the singing and spatial behaviour of wild birds.