If you build it, will they come? Macroinvertebrate community recovery patterns in ‘successful’ agricultural restoration efforts

Stream communities are shaped by regional-scale processes, yet the influence of regional conditions on local restoration outcomes remains underexplored. Biophysical stream restoration is a common response to environmental legislation but often reveals a disconnect between scientific understanding and policy objectives. In agricultural watersheds, physical habitat restoration ideally complements other best management practices (BMPs), including chemical and biological interventions. However, these landscapes are often heavily modified, with extensive bank erosion and riparian zone loss. In this study, physical habitat restoration was prioritised due to the absence of water quality guideline exceedances and in anticipation of ongoing BMP implementation. It had two main objectives: (1) to assess long-term trends in regional water quality and benthic macroinvertebrate communities across 14 sites in seven streams spanning a gradient of agricultural disturbance, evaluating the ecological integrity surrounding a previously degraded, restored reach; and (2) to use this regional dataset to evaluate restoration outcomes in Ridge Brook - a heavily impacted watershed restored in 2007 to support endangered and culturally significant fish habitat. Findings highlight the limitations of restoration in the absence of broader regional contexts, offering insights to guide future restoration strategies and policy alignment.