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The article presents the paper "Termites and fire: Current understanding and future research directions for improved savanna conservation," by Andrew B. Davies, Catherine L. Parr, and Berndt J. van Rensburg. It states that the paper aims to highlight the lack of published materials regarding the interactions between termites and fire. The authors compare studies from different continents and suggest ways on how termites respond to fire in various ways.

Tropical savannas and rainforests contrast in their flammability and the fire resilience of their associated species. While savanna species generally exhibit high resilience to burning, there is much debate about the fire resilience of forest-associated species, and the persistence of forest patches in a flammable savanna matrix. Where fire has been excluded, savanna tends on a trajectory towards forest, with an increase in forest-associated plants and animal species. This study tested the idea that given the high proportion of forest-associated taxa in long-unburnt savanna, the fauna of these areas would be expected to exhibit less resilience to fire than the fauna in frequently burnt savannas. The study investigated the immediate and short-term effects on ant assemblages of re-introducing fire into long-unburnt savanna in northern Australia. The ant fauna exhibited high resistance to fires, with no significant short-term change in mean abundance or species richness; instead, seasonality had a far stronger influence on overall ant activity. Fire caused dramatic declines in dominance of the patchily distributed forest-associated species Oecophylla smaragdina and Papyrius sp., but had no effect on overall dominance by open savanna species of Iridomyrmex. Dominance by Iridomyrmex pallidus declined, but this was compensated for by increases in I. reburrus, while two other species of Iridomyrmex showed no change. This indicates a high level of functional redundancy among dominant species of Iridomyrmex, which universally dominate open savanna communities, but not of dominant forest-associated species. Overall, our findings demonstrate a high degree of fire-resilience of the long-unburnt savanna ant fauna. Despite the occurrence of forest-associated species, the high proportion of savanna species persisting in this habitat means that long-unburnt savanna retains the general response characteristics of frequently burnt savanna. [ABSTRACT FROM AUTHOR]

This study reports on preliminary findings of habitat-contingent temporal variability in ant assemblages in Purnululu National Park in northern Australia's semiarid tropics, by sampling at the end of the dry season (October 2004) and the end of the wet season (April 2005). Six grids of 15 pitfall traps were established in each of the spinifex, sandplain and gorge habitats. Community composition was dominated by behaviourally dominant ants ( Iridomyrmex spp.) and climate specialists ( Melophorus and Meranoplus spp.). Ant activity was higher in the wet season sampling period, with greater species richness and abundance. Interestingly, temporal variation in ant assemblage richness, abundance and composition varied markedly with habitat type. While there were large differences between sampling periods for the spinifex and sandplain habitat, this was not the case in the gorges. These temporal changes in ant assemblages are postulated to be linked with major environmental differences between the two sampling periods, driven by seasonal climatic conditions. It is likely that these changes influenced the ant assemblages through species differences in physiological tolerance levels, ecological requirements and competitive ability. This study demonstrates the need, in highly seasonal environments, to consider the temporal context of studies in relation to habitat type, particularly when undertaking biodiversity surveys and monitoring. [ABSTRACT FROM AUTHOR]

Abstract Fire is a key ecological process in several biomes worldwide. Although many conservation agencies have the protection of biodiversity as at least one of their major goals, information on the effects of fire on fauna in these biomes is fragmentary. Here we provide an overview of the published research undertaken to date on the effects of fire on fauna using examples from Southern Africa. We found that few studies have examined the effects of fire on amphibians or reptiles, and work on invertebrates is likewise sparse. The majority of studies that have been published are observational reports, and few experimental studies have been undertaken using an experimental fire regime, or over appropriately long time intervals. Replication was often not reported and where this was done, it was generally inadequate. The majority of the studies failed to report the area over which the studies were undertaken and sampling unit size was often not reported. Despite the importance of fire duration, ignition method, season and time of day of fire, few studies investigated these variables. We conclude that at present the information on the effects of fire on fauna in Southern Africa is fragmentary and, consequently, informed management decisions regarding the consequences of burning policies on the conservation of biodiversity both within and outside protected areas are problematic. We recommend that future studies, both in Southern Africa and elsewhere, be based on a suite of large-scale and experimental approaches (the latter firmly grounded in the principles of sound experimental design), use non-classical statistics to explore the effects of large-scale or unreplicated fires, and where possible include baseline information such as that gathered in fragmentation experiments. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The structure of tropical savanna ecosystems is influenced by fire frequency and intensity. There is particular interest in the extent to which long-term fire exclusion can result in a shift from savanna to forest vegetation that is not easily reversed by the reintroduction of fire. This study examined changes in the structure and composition of a long-unburnt site within the northern Australian savannas following an extended period of active fire exclusion (>20 years), and the effect of the reintroducing fire through experimental fire regimes, including fires in the early and late dry season at a range of frequencies. After the long period of fire exclusion, the vegetation community was characterized by a well-developed midstorey and canopy layer, low grass cover, substantially higher densities of woody sprouts and saplings than frequently burnt savanna. The community composition included a high proportion of rainforest-affiliated species. Three years of experimental fires had no detectable effect on the overall composition of grass layer and woody plants but had an effect on woody vegetation structure. Continued fire exclusion further increased the density of woody stems, particularly in the midstorey (2.0-4.99 m), whereas moderate-intensity fires (>800 kW m−1) significantly reduced the density of midstorey stems. The reintroduction of higher moderate intensity fire events resulted in the vegetation in some compartments reverting to the open savanna structure typical of frequently burnt sites. Such rapid reversibility suggests that in general, the woody thickening resulting from long-term fire exclusion did not represent a biome shift to a non-savanna state. However, there was a small proportion of the site that could not sustain the fires applied to them because grass cover was very low and patchy and therefore appeared to have crossed an ecological threshold towards closed forest. [ABSTRACT FROM AUTHOR]