EDP Foz Tua Nocturnal Birds - Ecological Monitoring Program, Exploration Phase [2018-2020]

Study Extent

The data were collected within a 5-km buffer around the Tua lower valley (Northeast Portugal), up to 50 km from the mouth, in the municipalities of Carrazeda de Ansiães, Alijó, Vila Flor, Murça and Mirandela.

Sampling

Sampling was designed to cover the main habitat types for nocturnal birds in, and around the lower Tua river valley under influence of the Foz-Tua dam in the exploration phase. Each sampling point was visited three times per year in winter (December-February) and spring (April-June), for playback calls. The methodology consisted in spontaneous listening (without any playback) for five minutes, during which all "natural" contacts were recorded, followed by song playbacks and vocalization recordings for one minute to induce audible responses of individuals of Bubo bubo. The playbacks were followed by a fixed listening time (three minutes), where all contacts with any nocturnal species were recorded. This procedure was repeated three times in each sampling point. All censuses begun 15 minutes after sunset and proceed up to two hours (maximum) after the first listening.

Quality Control

All identifications were carried out by qualified technicians

Method steps

1. To be completed

The taxonomic coverage spans 1 phylum, 1 class, 2 orders, 3 families, 5 genera and 5 species.

1. Chordata
   rank: phylum
2. Aves
   rank: class
3. Strigiformes
   rank: order
4. Caprimulgiformes
   rank: order
5. Strigidae
   rank: family
6. Tytonidae
   rank: family
7. Caprimulgidae
   rank: family

Data were collected within a 5-km buffer around the valley of the River Tua (Northeast Portugal), in Trás-os-Montes e Alto Douro region, up to 50 km from the mouth, in the municipalities of Carrazeda de Ansiães, Alijó, Vila Flor, Murça and Mirandela.