Africanized honey bees pollinate and preempt the pollen of Spondias mombin (Anacardiaceae) flowers

The invasion of generalist Africanized honey bees may change certain plant-pollinator interactions. We evaluated the preemption by honey bees and the exploitative competition with native bees on a tree with nocturnally dehiscent small flowers. Our main objectives were to quantify pollen production and harvesting, to verify whether honey bees exploitatively compete with native bees and to identify the effective pollinators of Spondias mombin. The nocturnally dehiscent flowers were pollen depleted by honey bees and attracted various nocturnal and diurnal bee species. A threefold increase in native bee abundance was produced by delaying pollen availability and by preventing the preemption of pollen by honey bees. The results suggest that honey bees reduce the foraging benefit of late-arriving native bees. Honey bees and Scaptotrigona aff. tubiba were regarded as the main effective pollinators of S. mombin due to their abundance, behavior, and ability to visit a large number of flowers.