Crop pests and predators exhibit inconsistent responses to surrounding landscape composition

The idea that noncrop habitatenhances pest controland represents a win–win opportunity to conserve biodiversity and bolsteryields has emerged as an agroecologicalparadigm. However, while noncrop habitatin landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitatmay be biological in origin or could result from variation in how habitatand biocontrol are measured. Here, we use a pest-controldatabase encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitatbut overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-controldynamics demonstrated little potential to explain variationacross studies, though prediction did improve when comparing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitatdoes not consistently improve pest management, meaning habitatconservation may bolsterproduction in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitatconservation truly represents a win–win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies.