The effect of caffeine on the epidemiology of Nosema bombi a detrimental bumblebee parasite
Arran J Folly, Arran J Folly , Philip C Stevenson , Mark JF Brown
Royal Holloway University of London, UK; Royal Holloway University of London, UK ; Kew Gardens, University of Greenwich, UK ; Royal Holloway University of London, UK
Understanding disease epidemiology is fundamental to elucidating the true impact of a parasite on its host. Bumblebees are key global pollinators, but are susceptible to a number of unicellular parasites that can impact on their health. One such parasite, the microsporidian Nosema bombi, has been associated with declines in a number of North American bumblebee species. Previous work has shown how individual bees may become infected with N. bombi and how the infection may then transmit to conspecifics. Here, we provide the first detailed analysis of the intra-colony epidemiology of N. bombi. We then address how ecologically relevant levels of the phytochemical caffeine, found in the nectar of plants that bumblebees are known to forage on, impacts the epidemiology of N. bombi. Our results suggest that determining the chemical profile of forage plants is key to understanding how landscapes can impact on disease epidemiology in an important pollinator.