The more the merrier: evaluating managed pollinators in highbush blueberry
Farina, Walter et al. (2020), The more the merrier: evaluating managed pollinators in highbush blueberry, Dryad, Dataset, https://doi.org/10.5061/dryad.gqnk98sk3
As the global stock of Apis mellifera colonies is growing slower than agricultural demands for pollination services, there is great interest in managing alternative species. Highbush blueberry floral morphology limits the access of bees to nectar and pollen, requiring growers to rent a considerable number of beehives. Recently, the South American bumblebee Bombus pauloensis is increasingly managed alongside honeybees. Herein, we evaluated their foraging patterns, in relation to the potential pollen transfer between two blueberry co-blooming varieties grown under open high tunnels during two seasons considering different colony densities. Both managed pollinators showed different foraging patterns, influenced by the cultivar identity which varied in their floral morphology and nectar production. Our results demonstrate that both species are efficient foragers on highbush blueberry and further suggest that they contribute positively to its pollination in complementary ways: while bumblebees were more effective at the individual level (visited more flowers and carried more pollen), the greater densities of honeybee foragers overcame the difficulties imposed by the flower morphology, irrespective of the stocking rate. This study supports the addition of managed native bumblebees alongside honeybees to enhance pollination services and emphasizes the importance of examining behavioural aspects to optimize management practices in pollinator-dependent crops.