Managed native bees (Scaptotrigona aff. postica) and wild pollinators impact on açaípalm (Euterpe oleraceaMart.) yield in eastern Brazilian Amazon. .

Agricultural expansion is a major driver of habitat loss, which triggers biodiversitydecline, including wild pollinators, and affects crop production. 76% of world crops are dependenton biotic pollination, therefore Integrated Crop Pollination (ICP), the arrangement of managed andwild bees combined with farm practices that support wild pollinators (e.g. habitat management),could help reverse negative impacts of pollinators deficit in tropical crops, while maximisingbenefits to producers. In the Amazon River delta, the Açaí palm (Euterpe oleracea Mart.Arecaceae) is unmatched among native forest plants in its cultural, social and economic importanceto the region. Its thick juice (?vinho do açaí?) is an important staple food in both rural and urbanpopulations. We applied the ICP approach to açaí palm production in the eastern Brazilian Amazonand evaluated the effects of a native managed stingless bee, Scaptotrigona postica, and landscape-level forest conservation on yield and socioeconomic outcomes, on 18 açaí palm plantations innortheast Pará state, Brazil. We found that managed stingless bees and forest cover enhancedflower visitor abundance on açaí palm inflorescences, but visitor abundance increases attributed tomanaged bees were associated with shifts in flower visitor evenness and diversity, due to reducedvisitation of wild bees close to managed colonies. Fruit production on inflorescences waspositively related to bee abundance and bee diversity. Consequently, overall pollination efficiencywas lower in plantations dominated by managed bees, especially when native forest cover in thesurroundings was low. At the hectare scale, managed bees and landscape-level forest conservationhad complementary effects on fruit yields, but additional costs of bee colonies mean profits werelargely explained by surrounding forest cover. We concluded that managed bees have greatpotential to boost açaí fruit yields, but the increased environmental and socioeconomic risksassociated with this activity indicates that growers should prioritise forest conservation and habitatrestoration to safeguard natural pollination ecosystem service and improve the overall sustainability of açaí fruit production in the eastern Brazilian Amazon.