Catastrophic wildfire and its short-term effects on families of Order Coleoptera (beetles) in Eucalyptus regnans forest in the Central Highlands of Victoria

Abstract

Summary The effects of a single high-intensity catastrophic wildfire on insect order Coleoptera (beetles) at litter level were assessed in wet sclerophyll Mountain Ash (Eucalyptus regnans F.Muell.) forest over a three year period. The study was based on 14 283 specimens representing 31 families contained in 1920 pitfall trap samples from a burnt ‘high elevation’ and ‘low elevation’ site, as well as an unburnt ‘control’ site. The effects of the wildfire were minimal, with only the predatory Carabidae (and therefore total predators) and the less common ‘minor’ families undergoing an apparent short-term decrease and increase in activity respectively within the two years following the wildfire. However, the activity of the more common ‘major’ families Staphylinidae, Nitidulidae, Leiodidae, Curculionidae and Cryptophagidae, and the decomposers/fungus feeding group remained unchanged after the fire. Coleopteran families in terms of diversity, taxon richness and community evenness were also found to be unaffected by the wildfire, as were the proportions of the total Coleoptera in the wider arthropod spectrum based on 91 929 specimens. Coleopteran families at litter level therefore appear to withstand, or recover fairly quickly from, the effects of a single catastrophic wildfire (and by inference also from a single low-intensity prescribed fire) so that the order must be considered as a fire-stable part of the E. regnans forest. However, further study is required to determine whether this apparent coleopteran stability at family level is also reflected at the genus and species level.