Contrasting effects of rice‐crayfish co‐culture on insect herbivores at field and landscape scales

Abstract BACKGROUND Insect herbivores threaten global agricultural productivity, and sustainable farming systems have been widely promoted to secure food security. However, how such systems affect pest populations across field and landscape scales, and whether such effects vary among pest species, remain poorly understood. As a major staple crop feeding half the global population, rice faces severe threats from multiple pests with divergent biological traits. Rice–crayfish co‐culture (RC) is a rapidly expanding sustainable rice farming system with ecological and economic benefits, yet its impacts on these rice pests remain unclear. We conducted a 4‐year field survey to investigate RC's effects on pest abundance at field and landscape scales, and whether such effects differ among pest species. RESULTS Across 43–55 paired fields, RC and rice monoculture fields did not significantly differ in the abundance of the white‐backed planthopper [ Sogatella furcifera (Horváth), WBPH], rice leaf folder [ Cnaphalocrocis medinalis (Guenée), RLF] and striped stem borer [ Chilo suppressalis (Walker), SSB] at the field scale. At the 3.0‐km landscape scale, increasing RC coverage was significantly positively linked to WBPH (estimate = 5.31 ± 1.54, P = 0.002) and RLF (estimate = 3.60 ± 1.67, P = 0.031) abundance, yet significantly negatively associated with SSB abundance (estimate = −5.11 ± 1.43, P < 0.001). CONCLUSIONS The impacts of RC on rice pests are scale‐dependent and species‐specific, shaped by pests’ distinct biological traits. Our findings highlight that multi‐scale, species‐specific research is critical for sustainable farming expansion, guiding targeted management instead of uniform control, avoiding unintended outbreaks while maximizing its benefits. © 2026 Society of Chemical Industry.