PHOTO: Sightings of the Pilliga koalas are becoming more isolated. Image: Liz Cutts.
Scientists are hoping they can study the surviving koala populations in the Pilliga to get a better understanding of how the animals are evolving to meet the current climate challenges.
The significant population drop of koalas, estimated to be at 80 per cent over three decades, in the once highly populated region has shocked scientists who observe the area.
In 1991 scientists surveyed the 535,000 hectare Pilliga Forests between Coonabarabran and Narribri – the largest remaining tract of NSW native forest, west of the Great Divide. Of 280 sites that were surveyed in the 1990s, 210 had evidence of use by koalas. But when the surveys were repeated in 2011 only 44 of those 210 sites still showed any sign of use by koalas – a reduction of nearly 80 per cent. Of the 70 sites that had no koalas in 1991 only one showed evidence of koalas in 2011…