Australia’s koala population—listed as “Endangered” in Queensland, New South Wales, and the ACT since at least 2022—is now booming across the eastern seaboard, thanks to new data from Australia’s leading science body, the CSIRO. That is according to CSIRO’s National Koala Monitoring Programme (NKMP), which, since 2023, has used expert data rather than opinion to calculate koala numbers and disturbances, reporting populations at 729,000–918,000 as of May 2025—more than double last year’s estimate of 224,000–524,000.
In effect, current populations are now about twenty times greater than the number forecast by the Australian Koala Foundation – between 32,000 and 58,000 after the Black Summer bushfires, and crucially, more than double the populations estimated in 2012 (forecast to be between 144,000 and 605,000) when Koala populations were first listed as ‘vulnerable’ in New South Wales.
“The latest data-driven estimate for the size of the listed (NSW, ACT, QLD) koala population is between 398,000 and 569,000,” according to the CSIRO-managed program. “This estimate is substantially greater than previous NKMP estimates, arising from the incorporation of additional data from across a wider area and model improvements.” In addition, “the latest population estimate for the unlisted koala population (VIC, SA) is between 303,000 and 381,000 individuals,” it said, adding that the figure is also higher than previous NKMP estimates and varies for the same reasons as the listed population.
According to the CSIRO, “whilst these changes in the population estimates do not necessarily indicate a change in actual koala populations, but rather reflect more data being available and a refinement of the modelling approach from previous NKMP estimates. Like any data-driven model, the estimates themselves and associated confidence bounds will change as more data are added.”
While solely data-driven estimates have challenges—namely, limited and fragmented data—the CSIRO states they “have two distinct advances” over past estimates. First, there was a concerted effort to collate koala presence, absence, and abundance data from a wide range of sources: individuals, research organisations, community groups, local governments, and state governments. Second, there is an analytical framework combining all these disparate sources and data types.
Fact Check: Huge Study Finds Koalas’ Populations Are Not Endangered in NSW Park
The latest CSIRO data comes after Wood Central exclusively revealed that koala populations are ‘high and stable’ in NSW forests, particularly where public forests have not been affected by timber harvesting. That is according to research published by Dr Brad Law, the principal research scientist at the NSW Department of Primary Industries, and supported by Leroy Gonsalves, Traecey Brassil, and Isobel Kerr.
Published in April last year, Broad-scale acoustic monitoring of koala populations suggests metapopulation stability, but varying below rate, in the face of major disturbances and climate extremes, has, for the first time, used passive acoustic monitoring to analyse populations in state forests now earmarked for the Premier Minns’ enlarged Great Koala National Park.
According to Dr Law’s research, “regulated timber harvesting in state forests did not affect the trend of (koalas) either metric, nor did land tenure,” with state forests (where timber harvesting is permitted) or national parks having little impact on the population of koalas.
The findings come from a 7-year study (2015–2021) at more than 224 sites across 8.5 million hectares of forest. The study covers the 2019/20 Black Summer Fires. While Koalas are cryptic, “acoustic sampling over many thousands of hours, combined with semi-automated call recognition, has proved exceptionally effective at detecting the species,” with high precision. “Occupancy was high over an extensive area of habitat,” the research said. The study also found that the stable trend was maintained despite severe drought and megafires that burned about 30% of their habitat in 2019.
Scientists use GPS and LiDAR satellites to monitor impacts on koala coups.
The research comes after Dr Law’s published work, which used GPS tracking and remote sensing, including LiDAR satellites, to create timber mosaics to evaluate the impact of harvesting on Koala coups.
Working with Forestry Corp and the Port Macquarie Koala Hospital, Dr Law said GPS tracking and remote sensing “provides a detailed look at how koalas use the forest 5-10 years after timber harvesting.” “These results strongly support our acoustic surveys (previously published). They demonstrate high occupancy of koalas in northeast NSW and no difference in density between harvested state forest and controlled forest in national parks,” Dr Law said. He added that it also offers insights into how koalas use areas that are heavily managed or where regeneration and restoration are a significant part of the landscape.
