Impacts of prescribed fire on saproxylic beetles in loblolly pine logs

Abstract

Abstract. 1. Studies addressing the immediate impacts of fire on forest arthropod communities and their implications for conservation are few, particularly for species within dead wood. To investigate the effects of fire on saproxylic beetles (Coleoptera), we randomly assigned large‐diameter loblolly pine (Pinus taeda L.) logs to a forest scheduled for a prescribed burn (i.e. a low‐intensity surface fire) or to an adjacent unburned forest in Georgia, USA.2. Beginning 5 days after the fire, the logs were placed in rearing bags to capture emerging beetles. In total, 3457 individuals from 80 taxa were collected.3. While more than twice as many individuals were collected from unburned logs than from burned logs, none of the 21 most abundant (i.e. ≥10 individuals) taxa, with the exception of Dioedus punctatus LeConte (Tenebrionidae), was absent from burned logs. Furthermore, similar total numbers of species were collected from unburned (62) and burned (60) logs.4. Diplocoelus rudis (LeConte), Cathartosilvanus imbellis (LeConte) and Endeitoma dentata (Horn) were considerably more common in burned logs, suggesting rapid colonisation following the fire.5. There were no differences in community composition between treatments based on analyses of similarities (anosim) using presence–absence data. Community composition, however, did differ between treatments based on anosim using log‐transformed abundance data, but only for logs taken from a tree largely covered by bark, suggesting that the subcortical fauna is more strongly impacted.6. These results indicate that saproxylic beetles within large‐diameter loblolly pine logs can, for the most part, tolerate low‐intensity fires and need not recolonise burned sites.