The dataset contains records of the Eagle Owl (Bubo bubo) collected in the lower valley of River Sabor (NE Portugal), in the scope of the long-term Ecological Monitoring Program (PME) of the Baixo Sabor Hydroelectric Dams (AHBS), promoted by EDP – Energias de Portugal, S.A. This dataset includes results of surveys made in the area affected by the dams and in areas located upstream (river Sabor and rivers Angueira and Maçãs), from March 2015 to February 2020. Data consists of observations of the target species performed at fixed sampling points, from the river mouth up to 42 km. The surveys were carried out, by using the playback method, at a total of 37 of calling stations.