Researchers shocked to find several dead and emaciated koalas in Gunnedah last week say they're "terrified" of what they might find when they next visit.
A team from the University of Sydney found five dead koalas and three near death in just 10 days south of Gunnedah while they were conducting a temperature study.
Zoologist Dr Valentina Mella said all 31 koalas captured for the study were in bad condition from the drought and she is "terrified that the next time we go out there, they'll all be dead".
"Koalas need the trees and the trees are dying," she said.
"They're literally starving. There are no leaves for them to eat ... those animals had barely any food in their bellies. It's really bad. We were quite shocked.
"We've never had this many animals in such bad condition."
Related story: High heat delays Gunnedah koala chlamydia vaccine trial
Dr Mella said she hadn't slept well since she returned because she had been so worried about the koalas.
"It was just depressing ... we've never had a 10-day trip where we found five koalas dead," she said.
"The three we took into care [with WIRES], they were going to go. They were at the base of trees, they were unresponsive and you could pick them up, and you can't normally do that.
"I think it was the right decision to not do the [chlamydia] vaccine this time, because they're under a lot of stress."
Koalas need the trees and the trees are dying.- Dr Valentina Mella, University of Sydney
Dr Mella said the team was now considering doing a population survey; they think the numbers may have dropped by 20 per cent since their last one in 2017.
"It's not looking good in terms of the status of the population. We're worried we're looking at the same situation we had in 2009. It was drought and that was when disease started hitting," she said.
"We're trying to look at solutions - watering trees, fertilising trees - but how do you do it on a landscape scale? ... Who's going to pay for that?"
Dr Mella said they would meet with WIRES next week and will submit a proposal to the government, but it could take years to get the funds needed.
"We're hoping rain will come and make it better," she said.
The university is also looking for sponsors to fund a mass production of water containers designed by Gunnedah farmer Robert Frend, who owns a property the researchers use.
Data from the temperature study will be analysed in the next six months to try and determine if koalas drinking water regularly cope better with the heat than koalas that don't.
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