Micro, local, landscape and regional drivers of bee biodiversity and pollination services delivery to coffee (Coffea canephora) in Uganda

Abstract

Bee diversity and pollination services delivery in coffee fields are known to be driven by micro, local, landscape and regional drivers. The purpose of this study was to provide empirical documentation of drivers of bee biodiversity and pollination services delivery to coffee (Coffea canephora) under local conditions in Uganda. On-farm pollination experiments were therefore conducted in 30 small-scale coffee farms with contrasting land-use and management characteristics. The results indicated that coffee flowers were visited by 24–38 bee species with meliponine bee species being the most frequent visitors. The highest fruit set (84%) was recorded in hand cross-pollination followed by open pollination (62%) and bagged flowers (0.8%) treatment. Coffee proportion potential yield and bee contribution to fruit set were positively related to bee abundance, species richness, foraging rate and to the amount of semi-natural habitats available in the surroundings of coffee fields. Distance to forest/wetland and cultivation intensity were negatively related to coffee proportion potential yield but positively related to coffee pollination limitation. Farmers would benefit from establishing coffee fields in the vicinity of natural habitats and from adopting pollinator-friendly farming and conservation practices such as increasing the area of semi-natural habitat features as well as promoting high on-farm tree cover to protect good pollinators (e.g. meliponine bees) of coffee in the landscape.