Pollinators in blackcurrant orchards: Spatio-temporal environmental effects and no evidence of competition with co-flowering resources

Agricultural intensification is threatening pollinators and associated ecosystem services. Flower strips and spontaneous floral cover are commonly recommended to support pollinators, but farmers often hesitate to adopt them, fearing competition with their crops. Here, we studied nine blackcurrant orchards in Burgundy, France, differing in local floral resources and surrounding landscape composition. We thus investigated (i) the potential competition for pollinators between blackcurrant flowers and flowers in adjacent inter-rows, and (ii) the effects of local and landscape factors through time on the abundance of five pollinator morpho-groups: Bombus spp., Apis mellifera, large bees, small bees, and hoverflies. We conducted transects in orchards at three different periods in spring to quantify the abundance of local flowers and pollinators. We characterised the landscape composition around sites within a 100 m and 500 m radii. We showed that in each morpho-group, pollinator abundance in blackcurrant bushes increased with pollinators in adjacent inter-rows and was unaffected by flower abundance there, suggesting an absence of competition. Pollinator morpho-groups responded differently to environmental factors, with variations throughout spring. Small bees were the most negatively affected by the distance from orchard edge, while hoverfly abundance highly increased with the number of flowers at the end of spring. Floral resources in the inter-row could support pollinators in spring, particularly hoverflies and poor dispersers like small bees. Given the variability in pollinator traits and rapid environmental changes, future research should focus on functional groups and fine-scale spatio-temporal analysis to better understand environmental impacts on pollinators and effectively guide conservation efforts.