Prescribed burning protects endangered tropical heathlands of the Arnhem Plateau, northern Australia.
There are concerns that frequent intense fires are reducing biodiversity on the Arnhem Plateau within Kakadu National Park, northern Australia. Since the 1980 s, prescribed burning in the early dry season has aimed to reduce the extent of late dry season wildfires. A programme of more strategic prescribed burning has been undertaken since 2007, aiming to increase intervals between fires affecting heathland and rain forest communities. We assess the effectiveness of prescribed burning in Kakadu's Stone Country using a Landsat satellite-derived fire history (1980-2011), in terms of achieving 'tolerable fire intervals' for dominant plant communities. Our analysis indicates that fire regimes have become substantially more favourable for biodiversity since the early 1980 s. Although annual extent of burning has remained unchanged, two significant changes in fire regimes have occurred over the long term: (i) a switch from late dry season dominance to early dry season dominance and (ii) an increase in the abundance of long-unburnt vegetation, both of which are likely to benefit biodiversity. Demonstrating the statistical significance of changes associated with recent, more strategic fire management (2007-2011) is limited by the short duration of this management approach, although there is evidence of increasing abundance of long-unburnt vegetation during this time. The view that the Arnhem Plateau's fire regimes are increasingly driving biodiversity loss (due to frequent late dry season wildfires) is erroneous; they are in a more benign state now than at any time over the last three decades, most likely due to extensive use of prescribed burning. Synthesis and applications. In highly fire-prone landscapes, such as savannas, prescribed burning can be an effective means of: (i) bringing forward peak fire activity to the time of year when fire conditions are relatively mild and (ii) increasing abundance of long-unburnt vegetation. These changes are likely to favour persistence of a range of fire-sensitive communities. Our case study supports the strategic use of prescribed burning to protect fire-sensitive biota within highly fire-prone landscapes throughout the world.