Bumble bee (Bombus spp.) diversity differs between forested wetlands and clearcuts in the acadian forest1

Abstract

Bumble bees (species of Bombus Latreille, 1802) are important pollinators that are generally in population decline, but species presence and relative abundance are unknown in forested wetlands of the Acadian forest. To address this knowledge gap, we sampled bumble bees in forested wetlands and harvested sites (clearcuts) using vane and pan traps. We collected 617 specimens representing 11 species. We also included observations from iNaturalist (n = 70) in disturbed sites. We found that species-specific abundance in Acadian forested wetlands differed significantly from that in harvested sites. Wet coniferous forests with moderate to high herbaceous cover had greater overall bumble bee abundance than harvest sites. Species interactions may also influence community structure: sites with higher abundance of Bombus borealis Kirby, 1837 and B. ternarius Say, 1837 had fewer B. fervidus (Fabricius, 1798); B. flavidus Eversmann, 1852; and B. terricola Kirby, 1837. Differences in presence and abundance of bumble bee species may be explained by forested wetlands having a greater variety of flowering plants than forest harvest sites.