Abstract
Tropical savannas are the world’s most fire-prone biome, and savanna biotas are generally well adapted
to frequent fire. However, in northern Australia there are concerns that recent increases in the frequency and extent
of high-intensity fires are causing substantial declines in regional biodiversity values. In this paper we use two
well-studied and contrasting faunal groups, ants and small mammals, as case studies for reviewing faunal responses
to fire in Australian savannas.The Australian savanna ant fauna is dominated by arid-adapted taxa that are highly
resilient to frequent fire and are not considered to be threatened by prevailing fire regimes. Indeed, frequent fire
promotes ant diversity because it maintains an open habit that makes the dominant arid-adapted taxa feel at home.
Long-term fire exclusion reduces ant diversity due to a marked decline in arid-adapted taxa, and favours highly
generalized, more shade-tolerant taxa. In contrast, many small mammal species of high conservation value are
highly sensitive to frequent fire, and there are widespread concerns that their populations are threatened by current
fire management. Many of the species have shown dramatic population declines over recent decades, and, although
the causes are poorly understood, there is little doubt that fire is an important contributing factor. It is likely that
fire is acting synergistically with other underlying causes of decline, particularly predation by feral cats.The overall
resilience of most savanna animal species in relation to frequent fire suggests that they are secure under all but the
most extreme fire regimes. However, it is clear that more fire-sensitive groups such as small mammals need special
fire management attention.This needs to involve less frequent and finer-scale burning, along with the protection of
some large, infrequently burnt source areas.
Key words: ant, fire regime, fire resilience, frequent fire, small mammal.
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