Contemporary management has altered the fire regime of a large protected area: evaluating management outcomes and future directions

Abstract Background Effective fire management is critical to protect biodiversity in fire-prone protected areas. Performance indicators used to track fire management outcomes help identify changes in fire regimes and can support adaptive management. Here we determine fire management outcomes in Kakadu National Park, a large (> 19,000 km 2 ) World Heritage listed protected area in northern Australia, following the implementation of the Kakadu National Park Management Plan 2016–2026 (KNPMP). We evaluated achievement of four performance indicators aimed at reducing the area and frequency of large severe fires and fire patch size, and increasing the number and cumulative area of long unburnt vegetation patches. Analyses were undertaken for Kakadu’s three landforms (lowland, floodplain, escarpment) and we compared fire management outcomes since contemporary management was implemented in 2016 to reference conditions. Results Achievement of KNPMP fire management performance indicators was landform dependent. In the lowland, which covers 67% of Kakadu and experiences the most fire management, total burnt area and the frequency of late year fires (which are often more intense) decreased under contemporary management, while late dry season fire patch size reduced over time. Total burnt area decreased on the floodplain but did not change on the escarpment after KNPMP implementation, but fire frequency reduced in both these landforms, with a clear shift to early year burning. The number of energetically extreme fires also reduced in the lowland and escarpment. Despite this, large fires (≥ 1 km 2 ) still accounted for most of Kakadu’s burning. Contemporary fire regime shifts led to an increased number, but not cumulative area of long unburnt patches in the lowland and escarpment, though the cumulative area did increase on the floodplain. Long unburnt patches became smaller, occurring in areas that were topographically wetter and more rugged than the surrounding landscape. Conclusion While contemporary fire management achieved some of the KNPMP performance indicators, the ecological outcomes of the fire regime changes are unknown. Biodiversity responses have likely differed across landforms, but without direct ecological monitoring, their impacts cannot be evaluated. Future fire management in Kakadu National Park, and protected areas more generally, should be adequately resourced and guided by clear, measurable objectives linked to ecological outcomes.