Biodiversity impacts of the 2019–2020 Australian megafires
Don A. Driscoll, Kristina J. Macdonald, Rebecca K. Gibson, Tim S. Doherty, Dale G. Nimmo, Rachael H. Nolan, Euan G. Ritchie, Grant J. Williamson, Geoffrey W. Heard, Elizabeth M. Tasker, Rohan J. Bilney, Nick Porch, Rachael A Collett, Ross Crates, Alison Hewitt, Elise Pendall, Matthias M. Boer, Jody P. Gates, Rebecca L. Boulton, Christopher M. McLean, Heidi Groffen, Alex C. Maisey, Chad T. Beranek, Shelby A. Ryan, Alex Callen, Andrew J. Hamer, Andrew Stauber, Garry Daly, John Gould, Kaya Klop‐Toker, Michael Mahony, Oliver Kelly, Samantha L. Wallace, Sarah Stock, Christopher J. Weston, Liubov Volkova, Dennis M. Black, Heloise Gibb, Joshua J. Grubb, Mélodie A. McGeoch, Nick P. Murphy, Joshua S. Lee, Chris R. Dickman, Victor J. Neldner, Michael R. Ngugi, Vivianna Miritis, Frank Köhler, Marc Perri, Andrew J. Denham, Berin D. E. Mackenzie, Chris A. M. Reid, Julia T Rayment, Alfonsina Arriaga-Jiménez, Michael Hewins, Andrew J. Hicks, Brett A. Melbourne, Kendi F. Davies, Matthew E. Bitters, Grant D. Linley, Aaron C. Greenville, Jonathan K. Webb, Bridget Roberts, Mike Letnic, Owen Price, Zac C. Walker, Brad R. Murray, Elise Verhoeven, Alexandria Thomsen, David A. Keith, Jedda Lemmon, Mark K. J. Ooi, Vanessa L. Allen, Orsi Decker, Peter T. Green, Adnan Moussalli, Junn Kitt Foon, David B. Bryant, Ken Walker, Matthew J. Bruce, George Madani, Jeremy L Tscharke, Benjamin Wagner, Craig R. Nitschke, Carl R. Gosper, Colin J. Yates, Rebecca Dillon, Sarah Barrett, Emma E. Spencer, Glenda M. Wardle, Thomas M. Newsome, Stephanie Pulsford, Anu Singh, Adam Roff, Karen J. Marsh, Kye Mcdonald, Lachlan G. Howell, M. Lane, Romane Cristescu, Ryan R. Witt, Emma J. Cook
Abstract
With large wildfires becoming more frequent1,2, we must rapidly learn how megafires impact biodiversity to prioritize mitigation and improve policy. A key challenge is to discover how interactions among fire-regime components, drought and land tenure shape wildfire impacts. The globally unprecedented3,4 2019–2020 Australian megafires burnt more than 10 million hectares5, prompting major investment in biodiversity monitoring. Collated data include responses of more than 2,000 taxa, providing an unparalleled opportunity to quantify how megafires affect biodiversity. We reveal that the largest effects on plants and animals were in areas with frequent or recent past fires and within extensively burnt areas. Areas burnt at high severity, outside protected areas or under extreme drought also had larger effects. The effects included declines and increases after fire, with the largest responses in rainforests and by mammals. Our results implicate species interactions, dispersal and extent of in situ survival as mechanisms underlying fire responses. Building wildfire resilience into these ecosystems depends on reducing fire recurrence, including with rapid wildfire suppression in areas frequently burnt. Defending wet ecosystems, expanding protected areas and considering localized drought could also contribute. While these countermeasures can help mitigate the impacts of more frequent megafires, reversing anthropogenic climate change remains the urgent broad-scale solution. Data collected from more than 2,000 taxa provide an unparalleled opportunity to quantify how extreme wildfires affect biodiversity, revealing that the largest effects on plants and animals were in areas with frequent or recent past fires and within extensively burnt areas.