Study links colonisation of Australia to increased wildfire danger

Centre · 1A study published in Nature on Wednesday 7 October 2026 concludes that forest expansion and thickening after British colonisation made south-eastern Australian landscapes more prone to burning, amplifying the effect of climate change on the country's bushfire crisis. 1 Centre · 1The research was carried out by University of Melbourne researchers with the Gunaikurnai Land and Waters Aboriginal Corporation, and reconstructed 1,000 years of vegetation history in Croajingolong National Park, one of south-eastern Australia's most fire-prone forest regions. 1 Centre · 1The team took a metre-long sediment core from the bed of Purghagoolah (Lake Elusive), examined it at 0.5-centimetre intervals, and found that deposition changed suddenly about 200 years ago. 2

Centre · 1Before the British arrived, the GunaiKurnai had managed the landscape for thousands of years, mainly through cultural burning, and pollen shows open woodland with tree cover of around 10 per cent for 800 years. 2 Centre · 1New Scientist reports that between 1830 and 1860 European settlers massacred and forcibly removed the Indigenous population and cultural burning ceased. Shrubs moved in, charcoal evidence shows fires became hotter, eucalypt regeneration thickened and tree cover rose to around 40 per cent. 2 Centre · 2Anadolu Agency summarises the findings as increased fire temperatures, a fourfold increase in eucalypt cover, the transformation of open woodland into forest and increased soil erosion. New Scientist adds that the first evidence of soil erosion in the thousand-year record appeared at the same time, and that other sites in south-eastern Australia show up to six times as many eucalypts as in the past. 1 2

Centre · 1Lead author Michael-Shawn Fletcher of the University of Melbourne says the catastrophic fires now seen are "the product of colonisation and the product of land-use change, not solely the product of climate change", and that higher temperatures and drought combined with denser eucalypt forest drove the 2019-20 "black summer" fires, which burned 24 million hectares. 2 Centre · 1Fletcher says comparably dangerous fire weather, as in the Ash Wednesday and Black Saturday seasons, recurred in the region before colonisation, but the open landscape kept by cultural burning protected it from catastrophic fire; in a University of Melbourne statement he said "When Country is cared for, climate does not dictate wildfire." 1 Centre · 2Fletcher says the work supports cultural burning and the integration of Indigenous knowledge into fire management, and that a return to widespread cultural burning would reduce fire intensity and impact even though climate change will keep driving wildfires. He also argues that dense forests cannot store carbon securely because they are so prone to burning. 1 2

Centre · 1Other researchers quoted by New Scientist support the findings: David Bowman of the University of Tasmania says the study reinforces earlier research and will energise debate on sustainable fire management and Aboriginal fire groups, while Michael Bird of James Cook University calls it "probably the clearest example yet" that pre-invasion landscapes were substantially altered by the removal of Indigenous fire management. 2