Landscape features affect bumblebee visitation to flowers in old fields and seed set in blueberries

Background/Question/Methods

We sought to determine what landscape features have positive effects on bumblebee pollination of flowers in old-fields and on seed-set in blueberries.  Previous studies have found that proximity to native habitat enhances bumblebee visitation and crop yield.  We censused pollinator visitation to flowers of 19 old-fields in Vermont and seed production of fruits at 16 blueberry farms.  We used GIS to assess landscape features in areas surrounding these fields and farms.  Through stepwise regression, we determined which landscape features had the greatest influence on bumblebee visitation and seed-set.

Results/Conclusions

The percent of the landscape covered with forest was the strongest predictor of bumblebee visitation to flowers in old-fields.  The percent of flowering species that are native was the second strongest predictor of bumblebee visitation.  Blueberry fields with the most "open space" (gardens, lawns, fields) around them produced fruits with the most viable seeds.  These results support the findings that proximity to, and abundance of, native and natural landscapes enhances pollination by native bees.