Inter-individual difference of one type of pulsed sounds produced by beluga whales ( Delphinapterus leucas )

Belugas often exchange one type of broadband pulsed sounds (termed PS1 calls) which possibly functions as a contact calls (Morisaka et al., 2013). Here we investigate how belugas embed their signature information into the PS1 calls. PS1 calls were recorded from each of five belugas including both sexes and various ages at the Port of Nagoya Public Aquarium using a broadband recording system when in isolation. Temporal and spectral acoustic parameters of PS1 calls were measured and compared among individuals. Kruskal-Wallis test revealed that inter-pulse intervals (IPIs), the number of pulses, and pulse rates of PS1 calls had significant differences among individuals, but duration did not (χ2 = 76.7, p