Habitat in flames: How climate change will affect fire risk across koala forests
Farzin Shabani, Mahyat Shafapour Tehrany, Mohsen Ahmadi, Bahareh Kalantar, Haluk Özener, K. B. Clancy, Atefeh Esmaeili, Ricardo Siqueira da Silva, Linda J. Beaumont, John Llewelyn, Simon Jones, Alessandro Ossola
Abstract
Generate fire susceptibility maps for the present and 2070, to identify the threat wildfires pose to koalas now and under future climate change. Australia. Present and 2070. 60 main tree species browsed by koalas. The Decision Tree machine learning algorithm was applied to generate a fire susceptibility index (a measure of the potential for a given area or region to experience wildfires) using a dataset of conditioning factors, namely: altitude, aspect, rainfall, distance from rivers, distance from roads, forest type, geology, koala presence and future dietary sources, land use-land cover (LULC), normalized difference vegetation index (NDVI), slope, soil, temperature, and wind speed. We found a general increase in susceptibility of Australian vegetation to bushfires overall. The simulation for current conditions indicated that 39.56% of total koala habitat has a fire susceptibility rating of “very high” or “high”, increasing to 44.61% by 2070. Queensland (QLD) and South Australia (SA) are predicted to lose a greater area of suitable habitat than other states, due to increased incidence of wildfires. Output showed that 65.24% and 89.11% of koala total habitat in QLD and SA, respectively, is projected to have a “very high” or “high” fire susceptibility rating. Wildfires will increasingly impact koala populations in the future. If this iconic and vulnerable marsupial is to be protected, conservation strategies need to be adapted to deal with this threat. It is crucial to strike a balance between ensuring that koala habitats and populations are not completely destroyed by fire while also allowing for forest rejuvenation and regeneration through periodic burns.