River infrastructure and the spread of freshwater invasive species: Inferences from an experimentally‐parameterised individual‐based model

Invasive species and river infrastructure are major threats to freshwater biodiversity. These stressors commonly considered in isolation, yet the construction maintenance of can both enhance limit expansion invasive species. Spatial temporal limitations laboratory field studies, coupled with little consideration population-level responses (e.g. invasion rate), have limited understanding efficacy for long-term, catchment-scale containment This study utilised an individual-based model (IBM) investigate ability a partial riverine barrier contain spread at large spatio-temporal scales, using American signal crayfish Pacifastacus leniusculus as The base (no barrier) accurately recreated longitudinal rates reported existing literature. A virtual was added model, passage structure parameterised literature results experiment that demonstrated no clear relationship between density efficiency Crump weir. Model outputs indicated weir downstream release point had effect on crayfish, whereas upstream slowed rate 6.5 years after it first encountered. After recovered pre-barrier levels, front 2.4 km further than predicted absence barrier, representing 1.73 year delay range expansion. Synthesis applications. Despite substantial negative impacts native biodiversity, also species, trade-off. demonstrates need consider positive ecological consequences when designing prioritisation techniques removal mitigation selective fish passage), suggests some cases barriers may provide useful integrated pest management tool.