Chapter Three - Detecting landscape scale consequences of insecticide use on invertebrate communities

Insecticides represent an important management tool in agriculture. They provide a low cost and efficacious approach to pest control, where they may be employed both reactively and pre-emptively. It is likely insecticides will continue to play a role in meeting the challenge of feeding a growing global population. The widespread use of insecticides creates potential for negative impacts on non-target invertebrate populations. Many countries have regulatory processes in place to manage these. However, there regulatory processes have potential limitations when it comes to detecting the long-term and large-scale consequences of insecticide use. For example, long-term sub-lethal effects resulting from low dose exposure durations are rarely considered in toxicity tests, while predictable additive effects of mixtures of active ingredient are often ignored. In order to address this data gap, there is substantial scope for using existing spatially and temporally explicit biological records of species occurrence. This could help in monitoring and assessment to support our responsibilities to maintain biodiversity while continuing to grow enough food to feed the human population. How this is achieved poses several problems, both practical and analytical. Here, we describe how national-scale data on the spatial and temporal distribution of native invertebrates can be combined with maps of large-scale insecticide application and exposure risk to explore the actual consequences for non-target native biodiversity. Understanding these impacts on native invertebrates will provide a vital evidence base to inform policy decisions that could complement existing regulatory processes.