Influence of habitat and microhabitat on carabid (Coleoptera: Carabidae) assemblages in four stand types

Abstract

AbstractStudies based on presence/absence of a species may provide insight into habitat associations, allowing the distribution of species to be predicted across the landscape. Our objective was to characterize the carabid fauna in three mature boreal forest types (conifer, mixedwood, and deciduous) and a disturbed habitat (clearcut) to provide baseline data on the carabid species inhabiting the major forest types of boreal northwestern Ontario. Only spring-active carabids were considered for logistical reasons. We further identified the coarse woody debris structure and microhabitat characteristics within these stand types to try to refine our ability to predict the within-stand occurrence of carabids. We found the carabid composition of deciduous stands (mixedwood and aspen) similar and typical of the carabid fauna found in mixedwood forest in other nearby studies. The important feature of these forest types may be the presence of a deciduous leaf litter layer. In contrast, spruce stands contained fewer species and individuals and a distinct carabid fauna. As predicted, the clearcut habitats were dominated by open habitat species, although the fauna was dissimilar to what was recorded in clearcut habitats in other studies within northwestern Ontario. Coarse woody debris appeared to be an important habitat attribute for several carabid species in clearcut habitats.