Natural processes influencing pollinator health.

Evidence from the last few decades indicates that pollinator abundance and diversity are at risk, with many species in decline. Anthropogenic impacts have been the focus of much recent work on the causes of these declines. However, natural processes, from plant chemistry, nutrition and microbial associations to landscape and habitat change, can also profoundly influence pollinator health. Here, we argue that these natural processes require greater attention and may even provide solutions to the deteriorating outlook for pollinators. Existing studies also focus on the decline of individuals and colonies and only occasionally at population levels. In the light of this we redefine pollinator health and argue that a top-down approach is required focusing at the ecological level of communities. We use examples from the primary research, opinion and review articles published in this special issue to illustrate how natural processes influence pollinator health, from community to individuals, and highlight where some of these processes could mitigate the challenges of anthropogenic and natural drivers of change. This article is part of the theme issue 'Natural processes influencing pollinator health: from chemistry to landscapes'.