Data from: Bumblebees avoid sucrose solution containing higher concentrations of Roundup

Herbicides are the most applied pesticide group and as such more research is needed to understand their potential impacts on bee health. However, while herbicides are designed to kill the plants they are applied to rather than insects, there is evidence showing that they can have adverse effects on bees. To understand the hazard these herbicides pose to bees, it is necessary to evaluate the risk of exposure, which is influenced by presence of herbicides in the environment and the extent to which bees interact with contaminated materials. We use a choice and no-choice test to determine if bumblebees would forage on feeders which contain commercial formulations of Roundup (Ultra and Biactive, respectively), compared to controls (sugar-water feeders).

We found in both experiments bumblebees foraged less on feeders which contained above field-realistic concentrations of Roundup formulations, and that during the no-choice test whole colonies reduced their consumption by ~ 50 % despite lacking other food sources. During the choice test when individual foragers were observed they avoided feeders containing high, yet field-realistic levels of Roundup Ultra. Whilst more research is needed to understand how this translates to field conditions, where bees would forage on real flowers this work provides useful information and insights for future studies for investigating the impacts of glyphosate in the form of both active substance and within commercial formulations.