Australian Humpback Whales and Ambient Noise

摘要

The goal of the Humpback Acoustic Research Collaboration (HARC) is to understand the behavioral responses of large marine mammals to their surrounding acoustic environment. The fundamental thesis of the HARC project is that the effects of ambient ocean noise from natural and anthropogenic sources on baleen whales (Humpback, Megaptera novaeangliae) can be deduced by making careful observations in the presence and absence of sound. Visual observations from land and surface vessels are coordinated with subsurface tracking of singing whales using hydrophone arrays. Detailed observations of individual whale behavior are made using sophisticated digital tags attached by suction cup to selected individuals to compliment the observations of pods and populations. The detailed structure of the ambient noise field, physical oceanography, and meteorology in the study site are characterized to define the physical acoustics of the environment. Observations are made during periods with and without varying levels of anthropogenically produced and naturally occurring noise. HARC involves an international group of participants from SIO, WHOI, Australia's DSTO, and the Univ. of Queensland. Experiments took place in the fall of 2003 and will continue in the fall of 2004 at Peregian beach, 150 km north of Brisbane in Queensland Australia. This region is visited by migrating, Humpback whales (>4500 individuals), most travelling within 10 km of the coast. The region has only sparse shipping traffic, usually less than 2-5 ships per day, and consequently has low background levels of ambient noise. In the 2004 field season over 400 hours of visual and acoustic tracking was accomplished; data were recorded from approximately 1100 whales. In addition, 20 whales were successfully tagged using DTAGs for 69 hours including 9 focal follows on mother/calf pairs. This data has been synchronized with surface and acoustic tracking, behavioral recording, and tissue sampling for sexual identification.