Winter ecology of prairie deer mice (Peromyscus maniculatus bairdii) in cultivated habitats: Implications for agricultural ecosystem services

•Our study investigated the winter ecology of prairie deer mice (Peromyscus maniculatus bairdii), which are permanent residents of row-crop fields in the Midwestern United Sates and may provide ecosystem services by regulating weed seed and waste grain populations.•We used a combination of novel spatial mark-recapture demographic and stable isotope dietary analyses to investigate the ecology of prairie deer mice within corn and soybean agro-ecosystems of west-central Indiana.•We found that overwinter populations were robust, capable of surviving across winter, and maintained diets dominated by waste grains.•We estimate that prairie deer mice consume 6.3kg/ha of waste corn and 7.1kg/ha of waste soybean seeds during the non-growing season – a substantial reduction in waste grains remaining on the soil surface following crop harvest.•Collectively, our results suggest that prairie deer mice make meaningful contributions to reducing waste-grain populations during winter in post-harvest row-crop fields, during a time of year when most other seed predators are inactive.