Like a moth to a flame: the effect of megafires on pollinators and pollination systems.

Abstract

Fire is a natural part of many ecosystems, however, as a consequence of climate change, unusually large 'megafires' are expected to increase in occurrence. Given their large spatial extent, the impacts of megafire on biodiversity and ecosystem functioning could differ substantially from the impacts of typically sized fires, even in fire-adapted ecosystems. In this review, we investigate the potential impacts of megafires on pollination systems. The extensive spatial extent of megafires can lead to large amounts of habitat being exposed to high severity fires which may increase insect mortality, especially for taxa that cannot take refuge in underground nests or other refuges. In the most extreme cases, megafires may result in the local - or global- extinction of plant and pollinator species, which, in turn can trigger co-extinctions and lessen the resilience of pollination networks. In addition, smoke can exacerbate initial mortality by interfering with insect sensory systems, decreasing foraging behaviours, and negatively impacting insect health and immunity. Worryingly, smoke can impact pollination systems thousands of kilometres away from the fire. The negative effects of megafires may be exacerbated by interconnected non-linear feedback loops such as extinction cascades, colony collapse and Allee effects which may make the response of pollination systems to fires harder to predict. Since megafires will almost certainly become a feature of our futures, understanding how interconnected stressors will impact on pollinators and pollination systems is key to safeguarding global pollination systems.