The dataset contains records of freshwater bivalves (Mollusca, Bivalvia) collected in the rivers Tua, Tuela and Rabaçal, in the scope of the Complementary Studies to the Environmental Impact Assessment of the Foz Tua Hydroelectric Dam, promoted by EDP – Energias de Portugal, S.A. Data were collected in July and October 2011, during field visits to 31 fixed stations.The main taxa targeted during the field visits were species from the families Unionidae, Margaritiferidae, Sphaeriidae and Cyrenidae.

The dataset contains records of terrestrial vertebrates (Amphibians, Reptiles and Macromammals) colected in the lower Tua river and included in the Baseline Studies of the Environmental Impact Assessment of the Foz Tua Hydroelectric Dam, promoted by EDP – Energias de Portugal, S.A. Data were collected between May and September 2006, during field visits to nine 5km-sections of the river Tua, between the mouth and the village of Cachão, 45 km upstream. The presence of taxa belonging to the target groups (individuals and/or evidence of occurrence, like scats or footprints) was recorded. Twenty-eight taxa were identified, 26 to the species rank (5 amphibians, 12 reptiles and 9 mammals), and two to the genus rank (1 amphibian and 1 mammal).

The dataset contains 708 records of 13 amphibian and 13 reptile species recorded in the lower reaches of the Sabor River (NE Portugal), and that were included in the baseline studies to define biodiversity offsets of the Baixo Sabor Hydroelectric Dam, promoted by EDP – Energias de Portugal, S.A.. Data was collected between March and November 2009, during thirty five (n=35) days/nights of field sampling carried out in the area to be flooded by the two reservoirs, and within a 5-km buffer around each reservoir. Surveys involved transects, dip-netting in waterbodies, and casual observations along trails and roads. Each individual observed was identified to the lowest possible taxonomic level, its position was recorded, and in case of capture it was released thereafter in the same place. All captures were conducted in accordance with the Portuguese laws and carried out under authorized licences 186/2009/CAPT (Instituto da Conservacão da Natureza e Florestas).

The dataset contains records of freshwater fishes collected in the Tua river sub-basin and included in the Complementary Studies to the Environmental Impact Assessment of the Foz Tua Hydroelectric Dam, promoted by EDP – Energias de Portugal, S.A. Data were collected in August 2011, during field visits to 17 fixed stations. Sampling was made using electrofishing, and it targeted all fish species. The following species were recorded: Achondrostoma oligolepis, Cobitis calderoni, Gambusia holbrooki, Lampetra planeri, Lepomis gibbosus, Luciobarbus bocagei, Pseudochondrostoma duriense, Salmo trutta subsp. fario, Squalius alburnoides, Squalius carolitertii.

The dataset contains records of arthropods collected in the lower reaches of the Tua river, and included in the Environmental Impact Assessment of the Foz Tua Hydroelectric Dam, promoted by EDP – Energias de Portugal, S.A. Most data was collected between June 2006 and June 2008, during field visits to 7 sections of the river Tua valley. The main taxa targeted during the field visits were Lepidoptera, Coleoptera, Hemiptera, Orthoptera, and Odonata. Part of the specimens have been kept in the private collections of the collectors indicated in the dataset.