by Jane Hammond
This article first appeared in the August 2004 edition of The Veterinarian.
Humpback whales are slaves to musical fashion and crave innovation, Queensland University School of Veterinary Science researcher Michael Noad said.
He and his team have been studying whale songs since 1995 to determine their purpose and examine how environmental noise affects the whales.
 They observed whales repeatedly sang individual songs but the songs changed over time.
Dr Noad said male humpbacks sang individual songs lasting 10 to 12 minutes with distinct patterns, like verses. They sang over the top of one another and did not chorus together. The songs were copied by other whales and changed as they migrated.
"We think the songs are a mating call used by the males," he said.
"All the whales in a particular population seem to sing the same song at the same time. But the interesting thing is that the pattern of the song changes and all the males make the same changes so they keep matching each other."
The changing song patterns were highlighted when about a dozen humpback whales from Western Australia joined the migration down the east coast of Australia in 1996 bringing with them their West Australian song, he said.
Within a few months the migrating whales on the east coast were singing the West Australian song.
"It was as if the song had jumped Australia," Dr Noad said. "It took off like wildfire."
He said there did not appear to be a lot of social dominance in humpback populations so it was unlikely particular leaders were responsible for changing the song patterns.
One theory for the song changes was that they resulted from a type of Chinese whispers with errors creeping in as the song was passed from whale to whale.
Dr Noad favoured the theory that whales crave novelty and want to be at the vanguard of changing song patterns because it gives them a mating advantage.
"The best analogy we have at the moment is that the song is a little bit like fashion and the whales are all trying to be trendy," he said.
"It may be that singing the latest version of the song indicates fitness and provides a mating advantage. Those singers that are left behind singing yesterday's song may suffer a disadvantage.
"They may be perceived as being unable to keep up and are not a good bet for mating."
On a calm day whale songs could be heard up to 100 kilometres away but on a windy day the sound was masked by background noise and would travel only a few kilometres.
Dr Noad said research was yet to determine if man-made noises including military sonar, had any effect on whale songs.
The research is part of an international project, the Humpback Acoustic Research Collaboration, funded by the US Office of Naval Research and involving the Australian Defence Science and Technology Organisation, Scripps Institution of Oceanography, Woods Hole Oceanographic Institution.
Sydney University and the Newcastle University researchers are also involved in the project.
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