Researchers have found no evidence of chlamydia in a wild koala population near Newcastle.
More than 2,000 koalas are believed to be living in the Sugarloaf-Stockrington State Conservation Area, a 35-minute drive from the city's CBD.
A report submitted to the NSW government's Draft Koala Conservation Strategy recommends habitat protection, installation of wildlife exclusion and long-term monitoring.
For Daryn McKenny, the Sugarloaf-Stockrington State Conservation Area feels like his backyard.
It was seven years ago that he first spotted a koala in this protected bushland, just a 35-minute drive from Newcastle's CBD.
Daryn McKenny, Gamilaraay and Wiradjuri man, has been tracking koalas in the Sugarloaf-Stockrington Conservation area for over seven years. ( Supplied: The University of Newcastle )
Since then, Mr McKenny has spent hundreds of hours observing and tracking koalas in the area using discreet, motion-activated trail cameras attached to trees.
The Gamilaraay and Wiradjuri man said walking on country was the key to spotting them.
"I've spent years looking for all the food trees out there, then looking at the messages they give through the tracks and scratchings on them," he said.
Daryn McKenny uses motion-activated trail cameras attached to trees to track koalas. ( Supplied: The University of Newcastle )
Mr McKenny's observations prompted Ryan Witt, a conservation scientist at the University of Newcastle, to study the area.
Since 2020, Dr Witt and his team, including Mr McKenny as Aboriginal lead, have spent more than 250 nights surveying koalas to monitor and track populations across 23,900 hectares.
Ryan Witt began studying koalas in the Sugarloaf-Stockrington Conservation area in 2022. ( ABC Newcastle: Laurise Dickson )
"We do this across consecutive nights to account for whether a koala is there on a particular night or not."
Ryan Witt (left) and Daryn McKenny. ( Supplied: The University of Newcastle )
In late 2025, the research team confirmed 292 koalas in the Sugarloaf-Stockrington area; however, drone surveys and modelling conducted in 2026 have revealed a much larger population.
"We think we have around 2,300 potential koalas in this landscape," Dr Witt said.
After noticing an influx of koala joeys on footage throughout 2026, Dr Witt turned his focus to the reproductive health of the Sugarloaf-Stockrington population.
According to Wildlife Health Australia (2023), the number of koalas infected with chlamydia can vary widely between wild populations, from zero to nearly 90 per cent.
Researchers have used drone technology to track koalas across the conservation area. ( Supplied: Daryn McKenny )
To test for the disease, University of Newcastle researchers used drones to locate koalas before collecting fresh scats.
The koala scat, or poo, was preserved on dry ice and transported to specialist laboratories at the University of the Sunshine Coast for genetic and disease testing.
"We found 27 wild koalas without any evidence of chlamydia at the time of testing," Dr Witt said.
Daryn McKenny and Ryan Witt track and monitor koalas across the reserve. ( Supplied: The University of Newcastle )
A review of wildlife rescue and clinical records from the Lower Hunter region between October 2022 and September 2026 also found no evidence of chlamydia among a further 27 koalas within 30 kilometres of the Sugarloaf-Stockrington State Conservation area.
Dr Witt said while his report's findings were encouraging, they also suggested low genetic diversity among the koalas.
"We think they've been isolated from other populations for some time, which could be why they don't appear to have any disease," he said.
Koala scats tested from the Sugarloaf-Stockrington State Conservation area are chlamydia-free. ( Supplied: Daryn McKenny )
Mark Krockenberger, a specialist veterinary pathologist at the University of Sydney, has studied infectious diseases in koalas for 20 years.
He said only three koala populations in NSW appeared to be chlamydia-free.
"In three years of sampling in southern Sydney, Kanangra-Boyd National Park and Narrandera in the Riverina, no disease was detected," said Professor Krockenberger.
Mark Krokenberger has been testing and monitoring koalas for disease in NSW. ( Supplied: University of Sydney )
Professor Krockenberger says continued monitoring would give researchers a better picture of koala health in the Sugarloaf-Stockrington area.
"Evidence supports that they are pushing out west of the Pacific Highway, which puts them at risk of contacting other populations with disease," he said.
"This does make it an area worthy of further study and conservation of koalas."
Dr Witt has submitted his research to the NSW government for consideration as part of the state's Draft Koala Conservation strategy , which sets out targeted actions to protect koalas and their habitat across the state.
He has recommended increased habitat protection in the Sugarloaf-Stockrington area, installing wildlife exclusion fencing and establishing ongoing, long-term monitoring of this koala population, including longitudinal disease screening.
Researchers from the University of Newcastle will continue to monitor the Sugarloaf-Stockrington State Conservation area for koalas. ( Supplied: Daryn McKenny )
