Breeding calls of adult Kentish Plovers ( Anarhynchus alexandrinus ) in Korea: a spectrographic and quantitative reevaluation, with vocal context and function

For shorebirds, vocalizations serve an essential function as communication signals in a wide range of contexts. To reveal their vocal usage and function, it is essential to comprehensively categorize vocalizations, and this necessitates a broader investigation of their behavioral contexts and spectrographic structures. We recorded the vocalizations of the Kentish Plover (Anarhynchus alexandrinus) and examined the vocal repertoire of adults during one breeding season on the west coast of South Korea. We categorized a total of 5,236 calls into 12 call types (A, Aa, B, B-long, C, D1, D2, A-long, S, S-A, F, and P) under spectrographic structures and behavioral contexts: affiliative (e.g. pair contacts, nest-reliefs, and parental callings to chicks), aggressive (e.g., territorial defense, competition, and threats), vigilance (e.g., alarm and alert), advertising, distraction display, and flying to escape. Compared with previous descriptive studies, our findings provide a more comprehensive description of the call types and behavioral contexts and clarify the multi-behavioral context usage of each type. This study provides visual and quantitative information on the breeding vocalizations of adult Kentish Plovers and offers a standardized reference for future research on vocalizations of the genus Anarhynchus.