Codebreakers
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The Haunting Beauty of Whales singing in the depths of the world's oceans is the focus of new research.
Dr Michael Noad, from the University's School of Veterinary Science, is leading a team of researchers trying to unravel the mystery of what humpback whales are singing about, and why they sing at all.
As part of an international project, the Humpback Acoustic Research Collaboration (HARC), the UQ team is also investigating how whales react to other noises in their environment.
Dr Noad hopes the research will shed new light on the growing controversy about how humangenerated noises affect marine life.
"There are many sources of noise in the ocean, including increased commercial shipping," he said. "However, most controversy arises from military sonar and the use of air-guns in oil-exploration. "The problem is there is so much we don't know about how humpbacks use sound. It is only when we know this that we can predict how the manufactured sounds may impact upon them."
Dr Noad, a lecturer in veterinary anatomy, said even though whale sound had been studied for many years, much remained a mystery.
"We know a bit about humpback whale behaviour and song structure, but still have little idea about how humpbacks use song to interact with each other and their environment," he said. "We know humpbacks sing tightly structured, long and complex songs and that they are only sung by the males, and then only in the breeding season."
The humpback is making a comeback since the dark days of indiscriminate hunting.
Dr Noad said where once the worldwide population had been reduced from 20,000 to 100 or 200, recent surveys had shown the numbers at around 5000.
HARC is a collaboration involving the Australian Defence Science and Technology Organisation (DSTO), Scripps Institution of Oceanography (SIO), Woods Hole Oceanographic Institution (WHOI), UQ, University of Sydney and University of Newcastle researchers.
The project is funded by the US Office of Naval Research primarily, with additional funds from DSTO.
DSTO and SIO are providing equipment and expertise, particularly in the areas of underwater acoustic measurement and sound playback.
The UQ team is organising the fieldwork and conducting visual and acoustic tracking, as well as collecting behavioural, photographic and genetic data.
Using a field site at Peregian Beach on Queensland's Sunshine Coast, researchers are using visual surveys from the shore, and an array of hydrophones anchored offshore, as well as tracking from a boat, to monitor whales.
Dr Noad said WHOI was also using suction-cup tags on the whales.
"The suction tags have a hydrophone which acts like another ear stuck on the side of the whales allowing us to hear what they hear as well as sensing their movements and the depths they go to," he said.
The study site lies on the migratory path of the east Australian population of humpback whales, one of the best-studied populations of baleen whales in the world.
Every year from May to August, humpback whales migrate north along Australia's east coast to the warmer waters of the breeding grounds inside the Great Barrier Reef, returning southwards to their feeding grounds from August to November.
More Information: http://www.uq.edu.au/vetschool/codebreakers
