Breaking the wildfire cycle: progressive fire management can shift fire regimes and improve ecosystem condition. A case study from a large conservation reserve in northern Australia

Abstract

Extensive late dry season fires in northern Australia have long been considered detrimental to biodiversity conservation, pastoral production and other cultural and landscape values. Fire management programs in these landscapes typically aim to shift the fire regime from wildfires occurring predominately in the late dry season (LDS), when they tend to be extensive and destructive, to prescribed burns in the early dry season (EDS), when fires are generally smaller and less intensive. The intent is to create heterogeneity in vegetation age classes, reduce the scale of LDS fires and, in doing so, retain long-unburnt vegetation, a critical asset for biodiversity in a flammable landscape. Boodjamulla National Park, in Queensland’s Gulf Country, experienced a cycle of large LDS wildfires every 5 years for most of its history as a pastoral property and park until a progressive EDS burning program was introduced. Although there is limited information for defining the ideal fire regime for spinifex (Triodia spp.) rangelands, this program has improved a range of spatial metrics which the Queensland Parks and Wildlife Service (QPWS) believes can only benefit biodiversity; these include decreased annual and LDS area burnt; a greater number of small burnt patches; shorter distances between recently burnt and long-unburnt spinifex; and, consequently, a greater area of long-unburnt spinifex embedded in the mosaic across the landscape. There has been an improvement in the ecological parameters of these landscapes, as well as the protection and persistence of fire-sensitive vegetation communities and species, because of the burn program.