Interspecific avoidance of song overlap in tropical songbirds: species-specific responses to acoustically similar and different intruders

Abstract To ensure effective acoustic communication, signals should reach receivers in the least distorted form possible. Animals use various short- and long-term strategies to avoid signal degradation masking. However, we still have an insufficient understanding of how animals’ vocal behaviour is impacted by vocalisations other animals their communities. We experimentally examined two tropical, sedentary, territorial songbirds Western Uganda—the scaly-breasted illadopsis ( Illadopsis albipectus ) green-backed camaroptera Camaroptera brachyura )—modify singing after simulated appearance new, unfamiliar competitors, whose songs vary similarity those species studied. found that sang significantly less during playback acoustically similar than different or silence avoided song overlapping with but not species. Green-backed more both intruders control containing silence, patterns overlap were random. Our results show even a single-point noise source present within territory can modify bird’s behaviour. The new sound may affect differently, depending part on level species’ song. mitigate effect masking, strategies, such as temporal avoidance redundancy. Studies examining adaptive abilities natural modified habitats are needed predict consequences changes community structure. Significance statement birds masking common space, particularly complex environment tropical forest. While multiple studies focused responses interference caused anthropogenic noise, individual structure has received little attention. intrusions levels into territories songbird birds’ behaviour, study responded differently. These suggest similarity, well ecology, response, which be important when predicting effects result habitat climate.