Life in challenging environments: identifying species trait-environment relationships in alpine bumblebees

• Applicant: Dr. Sabine Nooten
• Subject Area: Ecology and Biodiversity of Animals and Ecosystems, Organismic Interactions
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 445715161

Bumblebees are key pollinators in alpine ecosystems. They are well adapted to these challenging environments, with their short active vegetation periods, high levels of UV radiation, cold temperatures and dry air. However, bumblebees are rapidly declining and underlying mechanisms are species-specific and multifaceted. Climate change is exacerbating these declines. This project investigates fundamental ecological questions by bridging functional trait-based community and chemical ecology approaches. The aims are three-fold: To identify physiological limits of bumblebee distributions and their adaptations to environmental stress. To determine the role of desiccation related functional traits in shaping species’ abilities to inhabit cold and dry environments; these traits will include body size, hairiness and - for the first time - the insects’ cuticular hydrocarbons (CHCs). To evaluate the importance of species range size and nutrient status for CHC responses to new climatic conditions. I will compare performance-related traits between bumblebees in two ways: spatially, across elevational gradients, and temporally between current bumblebee communities and bumblebees collected more than a decade ago. I will then test experimentally how the CHC profiles change in response to new climatic conditions and their association with species range size, elevational origin and nutrition. The outcomes of this project will provide a much-needed trait-based mechanistic understanding of bumblebee declines and show ways forward for alpine bumblebee conservation. Consequently, this is a new avenue to pursue for insect conservation.

• DFG Programme: Research Grants