SYDNEY, May 18 (Xinhua) -- A once-thriving koala population has vanished, according to Australian researchers who on Thursday called for action to save the koalas from extinction.
Researchers from the University of the Sunshine Coast in the Australian state of Queensland conducted a study in the Fraser Coast region and were shocked to discover a seemingly sudden and unexpected decline of koalas in the area.
A public survey by the Tiaro and Land District Care Group just 15 years ago in 2003 recorded numerous koala sightings, but the researchers were unable to find even a single koala in the area, suggesting a localized extinction may have already occurred.
"If we keep having these localized extinctions, we'll turn around in 10 years and there'll be no koalas left," researcher Anthony Schultz told Xinhua.
"It was very surprising. Most of the time, when there is a large decline in population, we can say there was a specific reason for it. There's no obvious trigger and yet there's quite strong evidence for another localized extinction."
As part of the research commissioned by the Fraser Coast Council, Schulz visited the areas that were studied in the original survey to track the koala population, accompanied by detector dogs who are trained to sniff out koala scat or faeces.
The dogs are much more skilled at tracking than humans, according to Schultz, but they were unable to detect any koala leavings.
"The dogs are able to track scat from up to 6 months ago, so if they are not able to find anything, it means there have been no koalas in this area at all for the past 6 months," he said.
"We know there have been localized extinctions happening for some time now, now it appears we are witnessing yet another."
The findings surprised the researcher, who considered the area to be quite ideal for a healthy koala population, with a high prevalence of state forests and no major development in the area.
While there has been a spate of localized extinctions across the northern parts of Australia, Schultz said that the situation is reversed in the southern parts of the country, where koalas have begun to overpopulate their native habitats in some areas.
"It's difficult to get the conservation message across because people think all koalas are doing quite well when that's really not the case at all, especially in the north."
"All koalas look quite similar but they are different in the north and south and we need to conserve genetic diversity."
The Australian Koala Foundation estimated there are less than 100,000 koalas left in the wild and attributed habitat clearing as the primary reason for the decline.
"This is no surprise to me, in my eyes koalas are well on their way to extinction," Australian Koala Foundation CEO Deborah Tabart told Xinhua.
"Australia is lucky to still have animals in the wild, we need a protection act before it's too late."
Schlutz said the mystery remains as to what triggered the mass disappearance.
"This was just one very unexpected aspect of our research, so one of the most useful things we can do is to work out exactly when the koala population started to decline in this area," he said.