Ant diversity in relation to time since fire in a mallee landscape of South-Eastern Australia

Fire is a dominant process shaping the Australian landscape and in many regions the frequency and severity of wildfires are predicted to increase under climate change. The primary impact of fire on fauna is typically indirect through habitat change. In particular, in mesic forests different animal species are favoured at different times since fire as habitat complexity increases with vegetation recovery. However, this will not necessarily be the case in habitats with low complexity such as many of those occurring in arid and semi-arid regions. Here, we investigate the relationship between fire history and ant diversity and composition in semi-arid mallee of south-eastern Australia. We surveyed ants at 11 sites in the Little Desert National Park and nearby private land that last burnt 0.5, 6 or 40 years ago. We found no relationship between time since fire and either ant diversity or composition, and this can be explained by a lack of relationship between time since fire and vegetation cover. Our findings contrast with those for mallee bird species, which show clear successional patterns following fire, but are likely to be typical of ground-foraging fauna that lack specialized habitat requirements.