摘要：SummaryNeonicotinoids have been implicated in the large declines observed in insects such as bumblebees, an important group of pollinators. Neonicotinoids are agonists of nicotinic acetylcholine receptors that are found throughout the insect central nervous system and are the main mediators of synaptic neurotransmission. These receptors are important for the function of the insect central clock and circadian rhythms. The clock allows pollinators to coincide their activity with the availability of floral resources and favorable flight temperatures, as well as impact learning, navigation, and communication. Here we show that exposure to the field-relevant concentration of 10 μg/L imidacloprid caused a reduction in bumblebee foraging activity, locomotion, and foraging rhythmicity. Foragers showed an increase in daytime sleep and an increase in the proportion of activity occurring at night. This could reduce foraging and pollination opportunities, reducing the ability of the colony to grow and reproduce, endangering bee populations and crop yields.Graphical AbstractDisplay OmittedHighlights•Field-relevant concentrations of imidacloprid disrupt bumblebee foraging rhythms•Drugged foragers are inactive for more of the day and more active at night•Neonicotinoid-treated foragers are more arrhythmic•These effects occurred in naturalistic 12 h light:12 h dark light cyclesEcology; Biological Sciences; Zoology; Animal Physiology; Behavioral Neuroscience
