Effects of parasites and pathogens on bee cognition

1. Bees are key pollinators and their widespread decline has raised considerable concerns regarding the sustainability of ecosystems and food production. Many environmental stressors do not directly kill bees, but they alter their physiology and behaviour, ultimately impacting colonies and populations. 2. This review considers the impact of parasites and pathogens on bee cognition. 3. First the main parasites and pathogens of bees are described, as well as how they modify the foraging behaviour, learning and memory of their hosts. 4. Next, the various defence mechanisms developed by bees to mitigate these effects at both the individual and collective levels are examined. 5. Finally, there is a discussion on how integrating research on host parasites, animal behaviour and cognition will provide a more detailed assessment of the contribution of parasites and pathogens to declines in the bee population and help to inform constructive ecological interventions.