Ecosystem service of biological pest control in Australia: the role of non‐crop habitats within landscapes

Abstract

AbstractSemi‐natural areas surrounding field crops are generally shown to enhance natural enemies of pests and biocontrol services within field crops worldwide. However, most of the evidence comes from work conducted in temperate regions of the northern hemisphere and it remains unclear to what extent these conclusions hold true in other parts of the world. Here, we provide an overview of the research in Australia investigating the link between populations of pests and their natural enemies and the type, quality, quantity and spatial arrangement of non‐crop habitats surrounding field crops. There is strong evidence in Australia that exotic weeds support multiple pest species, but the link between weediness of semi‐natural habitats and biological pest control within field crops remains to be investigated. Further, woody vegetation in good condition (not grazed, with mid‐ and under‐story and good ground cover) appears to supports multiple natural enemies that move into crops, especially when in close proximity to the crop. The role of grasslands is less conclusive, and in some cases, other crops, such as lucerne, may play a major role for biocontrol within neighbouring crops. At the landscape scale, proportion of non‐crop vegetation had opposing results at different spatial scales and for different natural enemies. However, the research investigating landscape composition is scarce, particularly in relation to biological pest control. We conclude that non‐crop vegetation in a good condition is critical for developing solutions for improving biological pest control and reducing risk of pest outbreaks, but more research is needed to understand the mechanisms and develop reliable recommendations.