KOALA NEWS & SCIENCE
An informative monthly newsletter about successes & important announcements in koala conservation, and the latest scientific publications about koalas.
2025
Subscribe here: https://mailchi.mp/808fc4af1ee0/koala-news-science
New koala numbers for NSW not a solution, just a starting point. 11 December
Scientists and conservation groups urge caution – koalas haven’t increased in NSW, we’re just better at finding them.
https://www.theguardian.com/australia-news/2025/dec/11/nsw-koala-numbers-higher-than-previously-thought-but-new-data-may-not-show-true-picture
Looking after the important corridors in Sydney Basin NSW 10 December
A really excellent article showing the ways koalas move, and the important corridors Sydney needs to protect.
https://www.abc.net.au/news/2025-12-10/koala-corridors-under-threat-in-sydney-conservationists-warn/106099774
Leave out water for wildlife, but why, how and where? 1 January
Quite rightly, a lot of wildlife groups urge the public to leave out water for wildlife in hot conditions. This article explains how different animals use water, why and when they need it, and how critical it could be as we face another very hot summer.
https://www.koalaclancyfoundation.org.au/how-when-why-australian-animals-use-water-for-cooling-down-drinking/
Callous, unethical and cruel NSW government ignored expert warnings and koalas died 20 October
A panel of scientific experts advised against the translocation of Wollongong koalas into the south-east forests, but the department proceeded anyway. The translocation failed, with 8 out of the 13 dead, and the other 5 captured and returned to their original habitat. Several suffered for months, after being recaptured in April (due to the deaths of 3 koalas), and then returned to the southeast forests, where they all died.
https://www.theguardian.com/australia-news/2025/oct/20/koala-deaths-government-rejected-expert-advice-failed-reintroduction
….
Latest Koala Science:
….
Hohwieler, K., Piza Roca, C., Brunton, E., Ward, M. and Cristescu, R.H., 2025. Exploring the potential role of built environments in wildlife conservation during wildfires. Conservation Science and Practice, p.e70200. https://conbio.onlinelibrary.wiley.com/doi/abs/10.1111/csp2.70200
As the frequency and severity of wildfires continue to rise, fire refugia could play a critical role in reducing impacts on affected wildlife species. Fire refugia are areas which are naturally less likely to burn, for example, due to local climatic conditions. Yet, they may also exist outside of areas traditionally considered as refugia, such as areas close to human infrastructure, where active fire management strategies prioritize the safety of humans and their assets. We hypothesized that wildlife habitat within or in proximity to human infrastructure could function as fire refugia, and tested this for Endangered koala (Phascolarctos cinereus). We used fire extent and severity mapping of New South Wales, Australia, to investigate the relationship between land use and the likelihood of severe to extreme fire at locations where koalas had been recorded in the preceding 15 years. Our findings show that the likelihood of severe to extreme fire occurrence was lower in areas with intensive human use (residential, utilities and services, transport, industry and manufacturing, intensive farming, and infrastructure), and increased outwards from these areas. Our results support the notion that remaining koala habitat in urban and peri-urban landscapes could play a vital role as fire refugia in the face of climate change. We argue that populations of at-risk species inhabiting these areas should be targeted for increased protection and management, while emphasizing the continued importance of protecting remaining natural habitats.
..
Kotzur, I., Moore, B.D., Boer, M., Yebra, M. and Youngentob, K., 2025. Diel foliar moisture content recovery time occurs soon after midnight in Eucalyptus species of koala (Phascolarctos cinereus) habitats. bioRxiv, pp.2025-12. https://www.biorxiv.org/content/10.64898/2025.12.10.693569.abstract
Many herbivores are reliant on the foliar moisture content (FMC, the water mass as a percentage of the dry matter mass), of feed tree leaves, which may vary through the diel cycle. This includes koalas (Phascolarctos cinereus), who have heightened reliance on FMC during high temperatures. However, it is unknown how, and to what degree, FMC varies through the 24-hour period. In this experiment we measured live leaf FMC every three hours over the diel period by calibrating a near-infrared spectroscopy (NIRS) model from leaf-surface reflectance, for tree species associated with koala habitat. Coinciding with reflectance measurements, trees in a glasshouse were exposed to normal and extreme climatic conditions including heatwaves and a drought, while collecting concurrent climate variables and soil moisture content. Our analysis of FMC timeseries’ of glasshouse trees found the diel range of leaf FMC was 23 % dry weight (DW, i.e. 19 % fresh weight) on average, between a minimum and maximum diel range of 10 %DW and 46 %DW, as predicted by an accurate spectral regression model (r2=0.96, RMSE=9.29 %DW). Overall, FMC minima occurred at 13:30 and FMC had recovered to initial levels (7:30) by 1:30 the following morning, though near-recovery levels were reached earlier by 19:30. This result shows that during a single day and night koala tree species may vary the proportion of leaf moisture by about one fifth, on average, and the timing of canopy moisture recovery may discourage foraging in the evening on temporarily dry species, during hot conditions.
….
Buckley, M., Mitchell, K.J., Arnold, L.J., Reed, E.H. and Eberhard, R., 2025. Collagen fingerprinting and sequence analysis provides a molecular phylogeny of extinct Australian megafauna. Proceedings of the Royal Society B: Biological Sciences, 292(2058). https://royalsocietypublishing.org/rspb/article/292/2058/20250856/234164
During the Late Pleistocene, Sahul—the former land mass of Australia, Tasmania and New Guinea—faced one of the greatest waves of megafaunal extinctions on the planet, for reasons that remain highly debated. Yet how some of these extinct species relate to each other also remains unclear, with poor DNA preservation causing challenges for reconstructing phylogenies of extinct taxa using biomolecular data. Here, we use ZooMS collagen peptide mass fingerprinting to screen 51 marsupial bones from Tasmania, ranging in age from late Holocene to over 100 000 years old, to locate specimens of extinct megafauna with the best potential for peptide sequence analysis. We then carried out phylogenetic analyses of collagen peptide sequences, providing the first biomolecular evidence for the relationships of the extinct marsupial genera Zygomaturus, Palorchestes and Thylacoleo. Most notably, our collagen data raise the possibility that the koala (Phascolarctos cinereus) may be the closest living relative of Thylacoleo carnifex, the so-called ‘marsupial lion’. Furthermore, by yielding biomolecular data from specimens that far pre-date human arrival, our study demonstrates that ZooMS can be an important tool for establishing higher-resolution extinction chronologies for extinct megafauna from Sahul, which may help to more conclusively establish the cause of their extinction.
….
Fleming, C., Nugent, H., Quinteros, S.L., Fernando, B.S., Tyndall, J.D., Webb, J.K., Mella, V.S. and Huston, W.M., 2025. A pilot study of re-purposing drugs to treat koalas with chlamydia. Scientific Reports. https://www.nature.com/articles/s41598-025-29789-3
The koala (Phascolarctos cinereus) is an endangered species in parts of Australia, in part due to chlamydial infections. Treatment is difficult due to the hepatic metabolism of the koala, and the critical reliance on a gut microbiota for survival. This study aimed to identify new compounds for treatment of Chlamydia infections by screening a drug re-purposing library. Screening was conducted using an in vitro cell culture model prior to in vivo mouse infection model testing of two candidates identified from the in vitro screen. One lead, bisoprolol fumarate, showed an impact on chlamydial infection and burden in vitro and in vivo. Whilst the mechanism of action may not support progressing this lead further, the approach to screening the library and list of candidates may enable identification of other new koala treatments. This study demonstrates the potential to apply drug re-purposing to koala treatment and presents a list of candidates that could be explored further.
….
Johnson, D., Srivastava, S. and Shapcott, A., 2025. Koala response to post-fire recovery of forest habitat. Wildlife Research, p.WR25174. https://connectsci.au/wr/article-abstract/doi/10.1071/WR25174/267791
Context: The koala (Phascolarctos cinereus) is now listed as Endangered for most of its range, mainly due to habitat loss, however, wildfire is an increasing factor. Extensive wildfires in South-east Queensland in 2019 allowed us to monitor habitat recovery on a 230 Ha property, and assess habitat preferences of koalas in this location and in the surrounding region of 12,000 km2 Aims: The study aimed to determine if areas with koala presence records tend to burn more than others; if koalas are selective for forest type, terrain, tree species and tree size; and if their habitat recovers after fire and koala recolonisation occurs. Methods:. We used the Spot Assessment Technique on the property to survey for koala scat presence and tree species use. We measured GeoCBI on the property, and extrapolated this regionally using Differenced Normalised Burn Ratio from Sentinel-2 data to estimate fire severity. We used Atlas of Living Australia koala records as regional sample points for forest type, burn estimates, elevation, slope and aspect. Key results: The proportion of regional koala occurrence records in burnt areas was not significantly different to random. Koalas mostly utilised three particular tree species in our local study area and one of four forest types. Koala presence decreased after the first year of fire recovery, then increased slightly in the fourth year. Koalas consistently utilised larger trees. Regionally, koalas notably preferred two forest types out of 85 used. Most koalas occurred on flatter, lower elevations. Southern and eastern aspects were preferred. Conclusions: Koalas are selective for forest type, terrain, tree species and tree size. Implications: Contrary to some other studies which found that koala population recovery after fire took months, our study suggests that population recovery after fire could take years, and death or removal of large trees following severe fires will lead to reduced koala habitat.
..
Boyd, J., Johnston, S.D. and Palmieri, C., 2025. Steroidogenic Capacity of Ovarian Interstitial Tissue in the Koala (Phascolarctos cinereus): Morphological and Immunohistochemical Evidence. Biology, 15(1), p.47. https://www.mdpi.com/2079-7737/15/1/47
The koala ovary contains an unusually large amount of interstitial tissue (IT), the function of which is not well understood in this species. This study examined koala ovaries to identify the types of cells present in this tissue and to assess whether they express markers associated with the production of steroid hormones, which are important for regulating reproduction. By studying ovarian tissue from different reproductive phases, we found that koala IT consisted of two distinct cell types: one with the typical appearance of hormone-producing cells, and the second, smaller cell type, with the strongest evidence for the presence of key gonadotropin receptors and enzymes needed to produce steroid hormones. These signals were highest when the females were not in an active breeding phase and lowest during lactation, suggesting that the marker expression in this tissue changes across the reproductive cycle. These findings improve our understanding of koala reproductive biology and may assist future research aimed at supporting the conservation and management of this endangered marsupial.
…
Koala Science In Brief:
..
Neumann, G.B., Tarlinton, R., Korkuć, P., Gaffney, P.M., Viaud-Martinez, K.A., Urbaniak, S., Nobuta, K., Dayaram, A., Mulot, B., Tenes, K. and Alquezar-Planas, D.E., Multi-generational koala (Phascolarctos cinereus) pedigree analysis reveals rapid changes in heritable provirus load associated with life history traits. Nature Communications. https://nottingham-repository.worktribe.com/output/54939813
…..
Donnelly, L.F., Kjeldsen, S.R., Lott, M.J., Leigh, K., Field, M.A., Cooke, I.R., Wright, B.R. and Zenger, K.R., 2025. Development and Validation of a Standardised Genomic Tool for Conservation Management of the Koala (Phascolarctos cinereus). Animals, 15(23), p.3375. https://www.mdpi.com/2076-2615/15/23/3375
…..
Callaghan, J., Friebe, K. and Powell, A., 2025. Use of Population Viability Analysis to evaluate a koala (Phascolarctos cinereus) source population and its response to a gradual translocation harvest. Australian Zoologist, 44(4), pp.729-744. https://meridian.allenpress.com/australian-zoologist/article/44/4/729/508308
…..
Sommers, C., Hewson, M., Schlagloth, R. and George, S., 2025. Identifying and Mapping Prospective Koala Habitat on Woppa (Great Keppel Island), Queensland, to Explore Future Conservation Opportunities. Conservation, 5(4), p.72. https://www.mdpi.com/2673-7159/5/4/72
…
Previous Koala News & Science here:
Written by Janine Duffy President, Koala Clancy Foundation.
with support from Cheryl Egan, Organiser, Wild Koala Day.
Please send your important news & publications to president@koalaclancyfoundation.org.au before 29th of each month for possible inclusion.