Western North American bat populations are increasingly at risk from the emerging threats of climate change and the fungal disease white-nose syndrome, leading to a heightened urgency to understand western bat ecology and habitat use. At least thirteen species of bats, including three California Species of Concern and seven additional species at risk, inhabit coast redwood forests. Species activity patterns vary significantly across these forests, but the mechanisms behind bat distribution patterns are largely unknown. In summer 2019 and summer 2020, we conducted passive acoustic monitoring at 20 coast redwood forest sites in Mendocino and Sonoma Counties, including both old-growth groves and working forests. Study sites reflected the coastal gradient of fog-influenced climate. At each site, detectors were deployed in the riparian corridor for a minimum of four consecutive nights during each of four monitoring rounds. We used statistical models to relate species activity to environmental variables, including canopy height, Timber Harvesting Plan records, actively logged microclimate, historical climate, and stream channel area. Our study demonstrates that young, working forests also serve as critical habitat for sensitive bat populations, and managing these forests for bats may thus be as important for species conservation as managing in mature, protected areas.