Bee diversity and functional composition in grassland habitats of the tallgrass prairie

This study compared the bee assemblages of different grassland habitats in the tallgrass prairie landscape of southeastern Nebraska.  The goals were to identify correlations between bee diversity and abundance and floral resource availability, and to examine the functional composition of the pollinator community between grasslands of different quality.  Three habitat types were compared: remnant prairie, grazed pasture, and properties enrolled in the conservation reserve program (CRP).  Bee species richness, species diversity, and species abundances were measured.  Additionally, species were divided into functional groups according to foraging range, degree of plant specialization, nesting behavior, and sociality.  Results suggest that the correlation of bee abundance and species richness to floral resource availability is not strong in this particular landscape, although the assemblage of species differs in functional composition between habitat types.  While CRP had the greatest bee species richness and abundance, they were not as diverse as the remnant prairies, which had both the greatest bee diversity and forb diversity of the grasslands examined.  This has important implications for pollinator conservation planning and raises questions of how functional groups use habitats of different quality in fragmented landscapes.