Research report - updated - December 2022
As part of the NSW Koala Strategy, we have updated our independent research report with new DNA dietary analysis. Overall, the new research found koalas have clear browsing preferences but will eat what is available. We have synthesised the findings in our updated report.
This research is the most comprehensive conducted to date in NSW on how koalas and their habitat respond to harvesting.
The overall research findings and our substantive advice outlined in the previous version of the report have not changed. The research found selective harvesting did not adversely impact koala density, nor the nutritional quality of koala habitat. This suggests the koala protections and wider landscape protections codified the Coastal Integrated Forestry Operations Approval (Coastal IFOA) are effectively mitigating the risks from selective harvesting to date at the research sites.
Other research insights include:
- koala density was higher than anticipated in the surveyed forests and, as noted above was not reduced by selective harvesting
- koala density was mostly similar between state forest and national park sites
- selective harvesting at the treatment sites did not significantly change canopy tree species composition and, therefore, is not expected to impact on nutritional quality of koala habitat
- tree species composition is the key determinant of habitat nutritional quality for koalas
- tallowwood (Eucalyptus microcorys) and small-fruited grey gum (E. propinqua) were confirmed to be important diet species, in alignment with the Coastal IFOA koala browse tree list
- spotted gum (Corymbia maculata) and ironbarks (E. paniculata, E. siderophloia), while not included on the Coastal IFOA browse tree list were browsed by koalas to a considerable extent.
Our report recommends opportunities to improve outcomes for koalas, including reviewing koala browse trees listed under the Coastal IFOA.
In 2018, the NSW Government tasked the Commission under the NSW Koala Strategy to deliver independent research to better understand how koalas are responding to harvesting in state forests on the NSW north coast. Research findings are explained below.
In 2022, the NSW Government revised the NSW Koala Strategy. The strategy requires us to extend our independent research program to investigate how koalas are responding to intensive harvesting in state forests on the NSW north coast.
We are scoping the research with our independent expert panel. We will work closely with the Department of Planning and Environment, Forestry Corporation of NSW and the Department of Primary Industries in designing and delivering the research. We will also engage the community with research findings.
Koala and habitat response post-wildfires at the research sites
In August 2020, the NSW Forest Monitoring Steering Committee approved funding to investigate the impact of the 2019-20 wildfires on koalas and their habitat. This leveraged existing research from this program in a cost-effective way and provides priority information for decision making and community.
We established an expert panel comprising koala and forestry experts to support delivering a robust, and scientifically credible research program. The expert panel members include:
- Dr Desley Whisson
Senior Lecturer in Wildlife and Conservation, Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University
Dr Whisson is a terrestrial ecologist with 15 years’ experience in conducting applied research on koala ecology and management. She is particularly interested in the spatial ecology of koalas including their habitat use and movements in modified landscapes. Prior to joining Deakin University in 2007, Dr Whisson held positions with the South Australian government (managing the Koala program on Kangaroo Island), the University of California (UC Davis), and the National Autonomous University of Mexico.
- Dr Alistair Melzer
Adjunct Research Fellow, Koala Research CQ, School of Medical and Applied Sciences and research program leader for koala research, Central Queensland University
Dr Melzer, a field ecologist, has worked on koalas and their habitat for over 20 years. Most recently, he was a member of the Queensland Government Koala Expert Panel, providing advice on the most appropriate actions to reverse declining populations and ensure long-term persistence of south east Queensland’s koalas. Dr Melzer managed a multidisciplinary research team as Director of the Centre for Environmental Management from 2001 to 2006. He is currently involved in developing tools for rapid assessment of koala habitat health at local and landscape scales.
- Professor Patrick Baker
Professor of Silviculture and Forest Ecology, School of Ecosystem and Forest Sciences, University of Melbourne
Professor Baker studies forest dynamics and has 25 years of experience working in temperate and tropical forests studying the impacts of past disturbances and climate variability on current structure and composition. He has previously worked at the Harvard Institute of International Development, The Nature Conservancy of Hawaii, the US Forest Service, and Monash University. Professor Baker was an Australian Research Council Future Fellow from 2012 to 2017 focussing on developing silvicultural systems to make south-eastern Australian forests more resilient to climate change. He is currently a Charles Bullard Fellow at Harvard University (2020-2022).
Researchers engaged under our Koala Research Program will publish their research in peer-reviewed scientific journals.
The results on koala occupancy and density in response to harvesting were recently published in the Nature Portfolio of Journals titled Regulated timber harvesting does not reduce koala density in north-east forests of New South Wales.
Researchers have provided a report detailing their results on koala habitat nutritional quality. The addendum to this report (on page 35) also contains the results from the research on wildfire impacts to koala habitat.
The Commission will be updating this webpage as the project is implemented. If you would like to receive updates regarding this work, you can sign up to our mailing list.