Effects of harvesting and stubble management on abundance of pest rodents (Mus musculus) in a conservation agriculture system

BACKGROUND: The shift to more environmentally sensitive agricultural practices over the last several decades has changed farmland landscapes worldwide. Changes including no-till and retaining high biomass mulch has been coincident with an increase in rodent pests in South Africa, India, South America and Europe, indicating a possible conflict between conservation agriculture (CA) and rodent pest management. Research on effects of various crop management practices associated with CA on pest rodent population dynamics is needed to anticipate and develop CA-relevant management strategies. RESULTS: During the Australian 2020–2021 mouse plague, farmers used postharvest stubble management practices, including flattening and/or cutting, to reduce stubble cover in paddocks to lessen habitat suitability for pest house mice. We used this opportunity to assess the effects of both harvest and stubble management on the movement and abundance of mice in paddocks using mouse trapping and radio tracking. We found that most tracked mice remained resident in paddocks throughout harvest, and that mouse population abundance was generally unaffected by stubble management. CONCLUSION: Recent conversions to CA practices have changed how pest house mice use cropped land. Management practices that reduce postharvest habitat complexity do not appear to reduce the attractiveness of paddocks to mice, and further research into new management strategies in addition to toxic bait use is required as part of an integrated pest management approach.