As pollinators of both wild plants and crops, wild bees are important providers of ecosystem services. Despite being one of the most intensively surveyed regions in the world, Europe remains data deficient for more than half of its known bee species.
In an attempt to fill knowledge gaps and identify priority targets of survey efforts and conservation, this study investigated patterns of taxonomic and phylogenetic diversities of 1,500 wild bee species in Europe.
The authors first combined open data from GBIF with restricted datasets from the Status and Trends of European Pollinators (STEP) project and others sources, compiling, curating and verifying almost three million species occurrences across continental Europe.
Their subsequent analysis of taxonomic diversity revealed a latitudinal gradient with higher bee species richness in southern Europe, with North Macedonia showing the highest predicted diversity, and Norway the lowest. In the model, the best environmental predictors of high diversity were high solar radiation and arid climates.
The model of phylogenetic diversity presented moderate and homogenous values across the continent with fewer clear patterns than taxonomic diversity. Overall, however, southern Europe had the highest phylogenetic diversity, best predicted by high temperatures in the warmest month.
The authors identified some degree of under-sampling across more than 70 per cent of Europe, most markedly in the Balkans. Highlighting stark differences in the quality and coverage between open and restricted access datasets, the authors call for tools to structure and standardize data sharing.