Documenting Persistence of Most Eastern North American Bee Species (Hymenoptera: Apoidea: Anthophila) to 1990–2009

Abstract

The status of wild bees, the major group of pollinators in most biomes, has gained recognition as an important ecological and economic issue. Insufficient baseline data and taxonomic expertise for this understudied group has hindered efforts to assess the conservation status of the majority of wild bee species. To more objectively address their current conservation status, we drew upon museum collections and the expertise of melittologists (biologists studying non-Apis bees) to compile a complete list of bee species for eastern North America, discriminating those which have and have not been detected during the past 20 years. The vast majority (95% of about 770 eastern North American bee species) have been found again, at least once since 1990. The remaining 37 species were rarely collected before 1990 as well. Some may truly be at risk (or lost). Others are undoubtedly data deficient due to inadequate knowledge of their biology or hosts, or the geographic regions and local habitats where they occur. Distributional and ecological patterns among these missing species are discussed. Most were recorded in the region only from peripheral areas or areas known to be undersampled by recent collectors, such as the southeastern United States. Others are characterized by specialized life histories or they cannot be identified routinely in the absence of taxonomic revisions. Clearly, most eastern North American bee species have persisted until recent times, with no evidence of widespread recent extinctions. An absence of well-documented global extinctions of bee species does not warrant complacency regarding pollinator conservation, as our qualitative method does not lend itself to documenting range contractions, range fragmentation, or declines in abundance and species richness in local bee communities.