Humpback whale song recordings suggest common feeding ground occupation by multiple populations

• Published in: Scientific Reports
• Main Authors: Schall, Elena, Thomisch, Karolin, Boebel, Olaf, Gerlach, Gabriele, Mangia Woods, Sari, T. Roca, Irene, Van Opzeeland, Ilse
• Other Authors: Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Carl von Ossietzky University of Oldenburg, Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI)
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Science and Business Media LLC 2021
• Subjects: Multidisciplinary; Southern Ocean; Austral; Humpback Whale; Sea ice
• Online Access: http://dx.doi.org/10.1038/s41598-021-98295-z; https://www.nature.com/articles/s41598-021-98295-z.pdf; https://www.nature.com/articles/s41598-021-98295-z

Abstract Humpback whale males are known to sing on their low-latitude breeding grounds, but it is well established that songs are also commonly produced ‘off-season’ on the feeding grounds or during migration. This opens exciting opportunities to investigate migratory aggregations, study humpback whale behavioral plasticity and potentially even assign individual singers to specific breeding grounds. In this study, we analyzed passive acoustic data from 13 recording positions and multiple years (2011–2018) within the Atlantic sector of the Southern Ocean (ASSO). Humpback whale song was detected at nine recording positions in five years. Most songs were recorded in May, austral fall, coinciding with the rapid increase in sea ice concentration at most recording positions. The spatio-temporal pattern in humpback whale singing activity on Southern Ocean feeding grounds is most likely shaped by local prey availability and humpback whale migratory strategies. Furthermore, the comparative analyses of song structures clearly show a differentiation of two song groups, of which one was solely recorded at the western edge of the ASSO and the other song group was recorded throughout the ASSO. This new finding suggests a common feeding ground occupation by multiple humpback whale populations in the ASSO, allowing for cultural and potentially even genetic exchange among populations.