Crop pests and predators exhibit inconsistent responses to surrounding landscape composition
The idea that noncrop habitat enhances pest control and represents a win–win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bolster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conservation 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 (Karp et al. 2018).
Research Objectives
Assess the role of surrounding noncrop habitat in providing pest-control services to farmers
Determine to what extent landscape information alone can be used to model and predict variation in pest control across systems
Key Takeaways
Using a pest-control database 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 non-crop habitat but overall showing no consistent trend.
Associated Projects and Publications
When natural habitat fails to enhance biological pest control – Five hypotheses
Academic Collaborators
Daniel S. Karp*, University of Californ ia, Davis Rebecca Chaplin-Kramer, Stanford University Timothy D. Meehan, National Audubon Society Emily A. Martin, University of Würzburg Fabrice DeClerck, Biodiversity International Heather Grab, Cornell UniversityClaudio Gratton, University of Wisconsin, MadisonAshley E. Larsen, University of California, Santa BarbaraAlejandra Martínez-Salinas, Tropical Agricultural Research and Higher Education Center (CATIE)
*corresponding author
Megan E. O’Rourke, Virginia Polytechnic Institute and State UniversityAdrien Rusch, Université de Bordeaux Katja Poveda, Cornell UniversityMattias Jonsson, Swedish University of Agricultural Sciences Jay A. Rosenheim, University of California, Davis Nancy A. Schellhorn, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Teja Tscharntke, University of Goettingen Stephen D. Wratten, Lincoln UniversityWei Zhang, International Food Policy Research Institute