title: Bumblebee learning and memory is impaired by chronic exposure to a neonicotinoid pesticide.
abstract: Bumblebees are exposed to pesticides applied for crop protection while foraging on treated plants, with increasing evidence suggesting that this sublethal exposure has implications for pollinator declines. The challenges of navigating and learning to manipulate many different flowers underline the critical role learning plays for the foraging success and survival of bees. We assessed the impacts of both acute and chronic exposure to field-realistic levels of a widely applied neonicotinoid insecticide, thiamethoxam, on bumblebee odour learning and memory. Although bees exposed to acute doses showed conditioned responses less frequently than controls, we found no difference in the number of individuals able to learn at field-realistic exposure levels. However, following chronic pesticide exposure, bees exposed to field-realistic levels learnt more slowly and their short-term memory was significantly impaired following exposure to 2.4 ppb pesticide. These results indicate that field-realistic pesticide exposure can have appreciable impacts on learning and memory, with potential implications for essential individual behaviour and colony fitness.
authors.affiliation: School of Biological Sciences, Royal Holloway University of London, Egham, Surrey, TW20 0EX, UK.
authors.forename: Dara A
authors.initials: DA
authors.lastname: Stanley
authors.affiliation: School of Biological Sciences, Royal Holloway University of London, Egham, Surrey, TW20 0EX, UK.
authors.forename: Karen E
authors.initials: KE
authors.lastname: Smith
authors.affiliation: School of Biological Sciences, Royal Holloway University of London, Egham, Surrey, TW20 0EX, UK.|School of Environmental Sciences, University of Guelph, Guelph, Ontario, N1G 2W1, Canada.
authors.forename: Nigel E
authors.initials: NE
authors.lastname: Raine
mesh_terms: D000818:Animals; D001516:Bees / Q000187:drug effects / Q000502:physiology*; D056631:Colony Collapse; D004781:Environmental Exposure; D007306:Insecticides / Q000633:toxicity*; D007858:Learning / Q000187:drug effects*; D000073943:Neonicotinoids; D009574:Nitro Compounds / Q000633:toxicity*; D010078:Oxazines / Q000633:toxicity*; D000077922:Thiamethoxam; D013844:Thiazoles / Q000633:toxicity*
chemical_list: D007306:Insecticides; D000073943:Neonicotinoids; D009574:Nitro Compounds; D010078:Oxazines; D013844:Thiazoles; D000077922:Thiamethoxam