Partitioning Wild Bee and Hoverfly Contributions to Plant–Pollinator Network Structure in Fragmented Habitats

摘要

In complex plant—pollinator networks, distantly related taxa spanning a great trait diversity shape network architecture. We were interested in whether this functional diversity buffers against habitat loss and quantified contributions of wild bees and hoverflies to network structure in 32 calcareous grassland fragments near Gottingen, Germany. Species richness of both pollinator taxa declined with habitat loss. The associated loss of 80% of interactions resulted in small, tightly connected, and less specialized networks. Because wild bee and hoverfly loss contributed similarly to declining network specialization, we conclude that trait diversity among pollinators does not necessarily provide insurance during habitat loss.