2007, BTO, COWRIE Research, Further use of aerial surveys to detect bird displacement by offshore wind farms

The series was designed to assess the statistical power of detecting population declines in individual species counts linked to wind farm construction. Employing a methodology based on Generalized Linear Modelling (GLM) and randomization, the study used real count data from random sites by species, year, and month, generating hypothetical scenarios with a model-derived mean-to-variance ratio (P-scale factor). Through 1,000 randomization iterations and comparison of pre- and post-construction counts, the analysis determined the proportion of significant results using P value thresholds. The findings demonstrate that this approach provides robust estimation of statistical power for detecting site-level population declines, and it is recommended for use in similar ecological impact assessments involving temporal and spatial data.