• Patterns of variation in bee community at different spatio-temporal scales

Iam interested in how bee communities (species assemblage and functional traits) vary at different spatial and temporal scales. I found that in mass-flowering crops, the bee community is less diversified and has more social species than in semi-natural habitat. Also, given the importance of the spatial component of bee diversity turnover, I found a spatial scale at which one should concentrate conservation efforts in order to optimise the number of species promoted per unit area. I also collaborated on the national BELBEES project, and found a strong shift in bumblebee community at local and national scales in Belgium through the last century. I am also interested to analyse this question in other contexts, such as urban habitats (collaboration in the LIFE Urbanbees project). Or according to different agricultural schemes such as organic crops or natural forest (collaboration in the IRNAD institute of the University of Rio Negro in Argentina).

• Influence of spatio-temporal dynamics of floral resources on bee communities

I am also very interested in how spatio-temporal variations in floral resources from crops and wild plants affect bee communities. Agricultural landscapes have a high spatio-temporal instability of floral resources which can affect diversity and composition of insect communities and plant-insect interactions. During my PhD, I found a clear segregation pattern between honey bees and wild bees (include bumble bees). Honey bee foraging was tightly associated with mass-flowering crops, while wild bee foraging was linked to floral resources in semi-natural habitats, and bumble bees had an interesting intermediate strategy. My results stressed the need to address different bee groups with different management strategies to sustain and promote their populations. I am also studying this question with field and semi-field experimentations in native forest managed for firewood production, in collaboration in the IRNAD institute of the University of Rio Negro in Argentina.

• Evaluate the impact of honey bee colonies and their management strategies on pollination and wild pollinators

Actually, the honey bee Apis mellifera is the main used pollinator species used around the world for crop pollination, especially for fruit crops. But his real effectiveness on crop yield still unclear and hard to synthesize, due to the strong lack of knowledge about the colony management for the pollination service (colony density, number of placements, the distance between two placements, etc…). Moreover, massively introduced managed species (such as honey bees) can have negative consequences for plant-pollinator interactions. We showed that high density of honey bee colonies can perturb populations of wild bee foragers in semi-natural habitats. But the strength of these effects still unclear and increases the scientific controversy on this subject. In this context, I am working in collaboration with different scientists and lab to determine an optimal stocking rate of honey bee colonies to increase crop productivity and limit as the same time the potential negative impact of colony introduction on the native wild pollinator, native flora and their interactions.

• Integration of agricultural durability, beekeeping and sustainability of wild and managed bee populations to optimize pollinator management strategies