Music from Byron Bay Bluesfest is stressing and possibly killing koalas, according to a scientist who has studied the population – a claim that is vigorously denied by the festival and its consulting ecologists.
Dr Stephen Phillips from Biolink ecological consultants told Guardian Australia that of 20 surveyed koalas initially found close to the site of the northern NSW festival in 2010, none were alive today. He said the noise from the festival, which stressed the animals and forced them to move, was the main cause of the deaths.
Phillips was contracted by the festival to study the animals in 2010, when it first moved to its current site. Since then, the festival contracted other ecologists, and Phillips said their reports to council demonstrated the initial population had almost been wiped out.
“What used to be a very robust population is now no more,” Phillips said.
In a paper published this month in the journal Australian Mammalogy, Phillips showed the koalas were disturbed by the noise of the festival and uncharacteristically moved outside their home area, away from the noise, during the festival.
Of the seven koalas tracked with radio collars, the three that resided within 525 metres of the stage moved outside of their usual home range – something koalas tend not to do. And three other koalas that lived slightly further from the festival also moved away from the music, but stayed within their home range.
“Those sorts of actions are very costly for a marsupial like a koala,” said Phillips.
Koalas don’t tend to move large distances because their diet of eucalyptus contains very little energy. The stress from the noise and being forced to move can make them more susceptible to disease, he said. In addition, moving out of their home area along the ground can make them prone to attacks by wild dogs as well as aggressive interactions with other koalas.
After the 2010 festival headlined by Crowded House and Jack Johnson, two of the tracked koalas died – one named Renee and one named Sonny Boy. Their cause of death couldn’t be established, but Phillips said he thought it was caused by the music. To confirm that, he said the animals’ stress hormone levels during the festival needed to be studied.
Byron Bay Bluesfest denied the noise was a significant problem for the koalas, and put the deaths down to disease and wild dogs, which they said they were trying to eradicate.
University of Queensland wildlife researcher Dr Sean FitzGibbon said the work done by Phillips was valuable, but the koalas that moved to the outer edge of their home range during the festival could not be said to be avoiding the music.
“The koalas were still within their usual areas of activity, so how could their movements be regarded as aversive?” he said.
FitzGibbon agreed there had been a high rate of mortality among the koalas, but said it was mostly due to disease and that could not be attributed to stress. He said he believed the next most serious cause of death was wild dogs. There was no direct evidence of dogs attacking koalas but dogs have been seen in the area and more than a dozen have been killed by the festival.
Peter Noble, director of Byron Bay Bluesfest, told Guardian Australia: “Our wild dog eradication program over the past few years has produced zero attributable deaths we believe as a result of dog attacks.”
“I am passionate about koalas,” Noble said, adding that Bluesfest was the only music festival in the country with a koala management plan approved by the NSW Department of Planning and Environment. As part of that plan, the festival was improving the koala habitat by planting trees and treating sick koalas with antibiotics.
“I totally agree there are some effects of the festival but you need to keep them in context,” said FitzGibbon. “They’re short and insignificant and they’re not the things we should be focused on for the longer term management of that koala population.”
