The behavioural response of migrating humpback whales to a full seismic airgun array

• Published in: Proceedings of the Royal Society B: Biological Sciences
• Main Authors: Dunlop, Rebecca A, Noad, Michael J, McCauley, Robert D, Kniest, Eric, Slade, Robert, Paton, David, Cato, Douglas H
• Format: Article in Journal/Newspaper
• Language: English
• Published: Royal Society Publishing 2017
• Subjects: anthropogenic noise; behavioural response study; biological significance; humpback whale; seismic airgun; 1100 Agricultural and Biological Sciences; 1300 Biochemistry; Genetics and Molecular Biology; 2300 Environmental Science; 2400 Immunology and Microbiology; Humpback Whale; Megaptera novaeangliae
• Online Access: https://espace.library.uq.edu.au/view/UQ:706586

Despite concerns on the effects of noise from seismic survey airguns on marine organisms, there remains uncertainty as to the biological significance of any response. This study quantifies and interprets the response of migrating humpback whales (Megaptera novaeangliae) to a 3130 in3 (51.3l) commercial airgun array. We compare the behavioural responses to active trials (array operational; n = 34 whale groups), with responses to control trials (source vessel towing the array while silent; n = 33) and baseline studies of normal behaviour in the absence of the vessel (n = 85). No abnormal behaviours were recorded during the trials. However, in response to the active seismic array and the controls, the whales displayed changes in behaviour. Changes in respiration rate were of a similar magnitude to changes in baseline groups being joined by other animals suggesting any change group energetics was within their behavioural repertoire. However, the reduced progression southwards in response to the active treatments, for some cohorts, was below typical migratory speeds. This response was more likely to occur within 4 km from the array at received levels over 135 dB re 1 µPa2s.