Geographic variation in simple contact calls of Canadian beluga whales (Delphinapterus leucas)

Beluga whales, Delphinapterus leucas, are a highly social species with a complex and diverse vocal repertoire. Although extensively studied and classified, to date few attempts have been made to examine geographic variation in their calls. In this study, we examined geographic variation in simple contact calls (SCCs), specifically those that consist only of broadband pulsed trains, among four Canadian beluga populations from the Eastern Beaufort Sea (EBS), the Eastern High Arctic-Baffin Bay, St. Lawrence Estuary (SLE), and the Western Hudson Bay. Five acoustic parameters were measured for each call and compared among populations using multivariate discriminant analysis. Results of our study indicate that there is a degree of variation in SCCs among these four populations, with the most geographically distant populations of the SLE and EBS displaying the greatest degrees of dissimilarity in SCC structure relative to geographically closer populations. Further, these results align with genetic variation of Canadian beluga populations previously described in the literature. This study is the first descriptive population comparison of SCCs for beluga and establishes a baseline for continued work into this developing area of research.