19107
Open
SC/68C/NH/04
Blue whale song occurrence in Central and Western North Pacific Ocean
M Wood, A ?irovi?, EM Oleson
IWC
2021
Blue whales in the Northern Pacific singat least three distinct,population-specific songs. These populations can overlap in time and spaceas they migrate acrossthe ocean basin. Acoustic recorders were deployedat three locationsin the centraland westernNorthPacificOceanin 2015-2016 to determine whatpopulations were present in their vicinity andto investigateseasonality oftheirsinging behavior in the areas. Of the fourpossible song types, only Central/WesternPacific (CWP) song was observed. This song was detectedmost often around Wake Atoll, which is located in the central North Pacific.At the other two locations in the NorthernMariana Islands,offSaipan and Tinian, the calls were detected regularly but were less common. Calls were concentrated in the summer months, May through August, with smaller peaks in singing during winter months at the Mariana Island locations. Song at these locations peakedslightly earlier thanpeak song periods previously reported at higherlatitudes.