Blueberry pollination in large and small fields by contrasting bee communities

Pollination of many food crops is achieved by a combination of indigenous native bees and by managed bees brought to fields during crop bloom. To pollinate fields of highbush blueberry, Vaccinium corymbosum, large commercial farms rent colonies of Apis mellifera honey bees whereas most small isolated blueberry fields are not stocked with bees and are typically dependent on native pollinators. We measured bee communities and components of crop yield in blueberry farms of these contrasting types to determine whether there is a deficit in potential yield in either type of field. Observational samples in large commercial fields and small isolated fields during bloom revealed a contrasting community of pollinators in which large fields were dominated by A. mellifera (over 95% of bees) while almost 50% of pollinators in the small fields were native bee species. Fruit set, seed number, and berry size were measured across the sampled fields to determine the degree to which these two contrasting bee communities provide crop yield. This presentation will report on the levels of fruit set and berry size across these farms and whether crop yield is affected by the varying size and composition of the bee community present during bloom.