An Assessment of Non-Apis Bees as Fruit and Vegetable Crop Pollinators

Declines in pollinators around the globe, notably the loss of honey bees (Apis mellifera L.) to Colony Collapse Disorder, coupled with a dearth of quantitative data on non-Apis bee pollinators, led to this dissertation research, which documents the role of non-Apis bees in crop pollination in southwest Virginia. Major findings of this first study of its kind in the region were that non-Apis bees provided the majority of pollination—measured by visitation—for several economically important entomophilous crops (apple, blueberry, caneberry, and cucurbits); diverse bee populations may be helping to stabilize pollination service (105 species on crop flowers); landscape factors were better predictors of non-Apis crop pollination service than farm management factors or overall bee diversity; and non-Apis bees in the genera Andrena, Bombus, and Osmia were as constant as honey bees when foraging on apple. Non-Apis, primarily native, bees made up between 68 % (in caneberries) and 83 % (in cucurbits) of bees observed visiting crop flowers. While 37–59 species visited crop flowers, there was low correspondence between bee communities across or within crop systems (“within crop ” Jaccard similarity indices for richness ranged from 0.12–0.28). Bee community diversit