Abstract
Wind-farm planning requires practical methods for identifying potential ecological conflicts before detailed project-level surveys. Existing seabird sensitivity assessments are less suitable for species whose breeding distributions shift among years and whose marine use areas are difficult to delineate, because space use depends on colony location and central-place foraging constraints. Here, we present a screening framework for such species, using Little Tern Sternula albifrons in Japan as a case study. The framework integrates three components: (1) MaxEnt-based nesting suitability from 95 occupied 500-m grid cells, (2) energetically constrained foraging accessibility derived from a central-place foraging model parameterised with field observations and prey-energy data, and (3) wind-turbine response quantified from three-dimensional flight tracking. The MaxEnt model identified bare land as the strongest positive predictor of suitable nesting area, highlighting extensive high-potential coastal habitat. The foraging model estimated a maximum one-way foraging distance of 8.92 km from nesting colonies under the median prey-energy scenario, allowing marine use areas to be mapped from suitable nesting sites. Mapped areas overlapped with offshore wind projects under environmental impact assessment, and with government-designated pre-EIA planning areas. Ornithodolite tracking showed clear horizontal turbine avoidance, with significantly fewer approaches at radii of 60–140 m from turbine tower centres and no trajectories recorded within 70 m. Together, these components provide a first-pass spatial screen of potential conflict between offshore wind development and breeding Little Terns, identifying areas requiring detailed site-specific surveys. The framework is intended for early-stage screening and does not estimate collision mortality or population-level consequences.