Members of one of the healthiest koala populations in Sydney are dying at an alarming rate, as chlamydia-infected koalas and housing development inch closer to their habitat.

Koala deaths have more than doubled to 25 in the Campbelltown LGA during 2022 and 2023, data from the NSW government and animal rescue organisation WIRES shows. About 18 of those deaths were the result of car strikes.

The koalas remain Sydney’s only chlamydia-free population, but the disease is on their doorstep, located just 5 kilometres from the area. The disease can cause conjunctivitis, leading to blindness, bladder infections, and infertility in koalas.

WIRES volunteer and koala coordinator for the Wollondilly branch Emma Meadows has helped save koalas for the past five-and-a-half years, and said there had been a sharp increase in the number injured and killed each year. She puts it down to an increase in koalas and more people moving through the area, as well as greater reportage of incidents.

“This season, it feels like every call out is to another koala dying. I’ve come across more koala bodies than ever – it is not a nice thing to see,” she said.

Greens MP Cate Faehrmann said the high number of koala deaths was concerning given there were about 300 marsupials in the region.

Faehrmann said despite a report three years ago from the NSW chief scientist outlining what was necessary to save the Campbelltown koalas, the number of rescue call-outs has increased dramatically.

“One of the key recommendations in the chief scientist’s report into the protection of Campbelltown’s koalas was building a number of underpasses or overpasses along Appin Road. It’s inexcusable that these still haven’t been built and that there’s no commitment to do so any time soon,” Faehrmann said.