No abstract

No abstract

Rove beetles are useful subjects for Nearctic forest biodiversity work because they are abundant, diverse, and easily collected, and have strong habitat affinities. Excellent identification keys exist for most groups, although there is a dearth of ecological and life-history information. There is considerable variation in species composition and abundance within the active summer season and in abundance from year to year. Community composition varies among larger geographical regions and to a lesser extent among forest types in more localized areas. Within the Nearctic boreal forest there are significant differences between beetle communities from the eastern and western portions. For the most part, the same species tend to dominate rove beetle communities in the western boreal forest. At the landscape level there are differences in rove beetle communities along successional gradients. In the boreal forest the communities of younger aspen-dominated and older conifer-dominated stands are somewhat distinct, with intermediate-aged stands containing a mix of the two communities. At the ecosite and microsite level there is significant variation, which remains poorly understood. Fire is the dominant mode of disturbance in the Nearctic boreal forest. It has a profound effect on rove beetles by destroying the forest communities and resetting the successional trajectory to the earliest stages. The burn pattern results in a patchwork of different communities at various stages in the successional cycle. In contrast to fire, forest harvesting does not directly destroy the rove beetle community, but to a large extent it destroys the forest habitat. This results in a unique rove beetle community characterized by a mix of forest species and open-ground specialists, and overall high diversity in this period of flux. In the years after harvesting, the rove beetle community goes through successional changes and becomes more similar to the forest community, but it skips the early postfire stage and proceeds along the successional trajectory more rapidly than after fire. In at least one forest type in western Canada, the post-fire and post-harvest communities, though similar, have not converged after 29 years. Other less direct effects of harvesting on rove beetles are a decrease in the proportion of the land base suitable for communities associated with older successional stages; alteration of forests by post-harvest site preparations and planting of exotic tree species; edge and fragmentation effects that are detrimental to the remaining forest surrounding harvested areas; and an influx of exotic arthropod species with affinities for disturbed sites. More information is needed on the habitat affinities of individual species. It is recommended that future work explore the effects of post-harvest forestry activities, fragmentation, and edges on rove beetles in forested habitats. As well, such studies should consider the effects on beetles of riparian zones and wetlands.