Baixo Sabor: Eagle Owl (Bubo bubo) & Nocturnal Birds Surveys - Construction and Reservoir Filling Phases [2010-2014]

Acoustic sampling was performed at 32 count points, located in high ground near areas of favourable habitat for the Eagle Owl located along the lower Sabor river valley and its main tributaries, from the river mouth up to 42 km upstream. Each sampling point was visited ± 3 hours around sunset, corresponding to the period of greatest daily vocal activity of the Eagle Owl. In each point, a period of spontaneous listening of vocal activity was performed ("SCP", 8 minutes), followed by the playback of the Eagle Owl call (3 minutes) and for a final period of listening to the potential response of the focal, and other species ("PPP", 10 minutes). The identification of the responses was made "in loco" by experienced observers.