'What Does the Anemonefish Say?': Investigating Amphiprion percula's Acoustic Behaviour

Acoustic communication plays a critical role in mediating social interactions, coordinating behaviours and maintaining group cohesion in many animals. While fish are known to produce a diverse range of sounds, most studies have been conducted in laboratory settings, limiting our understanding of how vocalisations function in natural social and ecological contexts. In this study, we provide a comprehensive examination of vocal behaviour in social groups of orange anemonefish (Amphiprion percula), an anemonefish species with strict size-based hierarchies. Using underwater video and acoustic recordings from nine wild groups in Kimbe Bay, Papua New Guinea, we quantified acoustic features of individual vocalisations and linked them to behavioural contexts. We also examined the effect of body size and social status on vocalisation's acoustic features. Our findings demonstrate that A. percula's vocalisations differ between behavioural contexts, highlighting the role of acoustic signals in signalling submission, regulating conflict, and maintaining group hierarchy. Behavioural context emerged as the strongest predictor of vocal variation, with body size and social rank providing additional variation. This study underscores the importance of field-based investigations to capture the ecological and social complexity of acoustic communication. These findings establish a baseline for future functional studies, including playback experiments, and provide critical insight into the adaptive significance of sound in social fish communities.