Inter-specific variation of pesticide effect on European wild pollinators

Pollination is an essential ecosystem service that ensures the sustainability of wild plant communities and improves crop yields. It is estimated that insects provide pollination services worth 153 billion dollars a year worldwide and 14 billion dollars a year in the European Union (i.e. 10% of agricultural production). However, in the current context of the Anthropocene, human activities are causing a massive extinction of biodiversity across the globe, affecting many pollinators such as bees and lepidopterans (butterflies and moths). Among the causes of this decline, the use of plant protection chemicals is a major factor. However, current test standards are based mainly on a few bee species, such as the honey bee Apis mellifera, virtually excluding wild pollinators. Wild pollinating insects are very diverse, therefore the development of new protocols is a first essential step to assess their sensitivity to pesticides. To this end, several species of wild bees (Bombus terrestris, Bombus hypnorum, Andrena vaga and Colletes hederae) and wild lepidopterans (Aglais urticae, Macroglossum stellatarum, Papilio machaon, Saturnia pavonia, Maniolia jurtina) were selected to cover a large part of pollinators’ taxonomic range, reflecting a wide range of morphological traits and life histories. Initially, LD50s measurements were carried out on a model species belonging to each of these groups: Bombus terrestris and Algais urticae. By adapting these results and developing new protocols, we then tested the effect of acute and chronical exposure of all pollinator species to the main categories of pesticides (insecticide, fungicide, herbicide), alone or in mixtures, to assess and compare their sensitivity to these products at each stage of their life cycle (juvenile and adult). Measures of survival were accompanied by measures of fitness-associated morphological, behavioural and physiological traits.