Movhera Baixo Sabor: Fishes – Ecological and Compensatory Measures Monitoring Programs: exploration phase [2021-2023]

Study Extent

The data were collected along the Sabor lower valley (Northeast Portugal), up to 70 kms from the mouth, and in the Vilariça stream, in the municipalities of Torre de Moncorvo, Mogadouro, Macedo de Cavaleiros, Bragança and Vimioso.

Sampling

A total of 66 sampling stations was used to perform both monitoring programs. In 2021-2022, all stations were used for the Aquatic Ecosystems PME and the PMC (MC1 – “Compensation Habitat of the Vilariça Stream”, MC2 – “Recovery and Valuation of the Small Streams of the Sabor Basin” MC3 – “Valuation of the Riparian Corridor in the Upper Sabor and Maçãs Rivers” and MC10 – “General Plan of Protection and Valuation of Herpetofauna and Invertebrates of the AHBS”). Subsequently, the PMC programs were terminated or suspended, and several sampling points were realocated to the PME. Thus, in 2023 only 31 sampling stations were used, of which 22 came from the discontinued/suspended PMC. This adjusted monitoring network included sampling stations in the main course of the Sabor river, in the terminal parts of the Maçãs and Angueira river basins, as well as stations in the Azibo river and in several tributary streams (Zacarias, Vale de Moinhos, Inferno, Resinal, Holas and Ribeirinha streams). The new sampling follows a “survey monitoring” scheme (no impact/control points). However, the stations previously attributed to the PMC can always be reactivated as controls, if/when the respective sub-mesures are retaken. Sampling took place once a year, in June and July, over the course of several days. Sampling was carried out using the electrofishing method, following the guidelines contained in the standardized protocol, published by National Institute of Water (INAG) (INAG, 2008). Sampling was carried out from downstream to upstream of the waterline, with proper electrofishing equipment, adjusted (voltage and amperage) as a function of the electrical conductivity of the water (previously determined), thus allowing an increased efficiency of the fishing while avoiding fish injuries and mortality. After capture, the fish were handled carefully and kept, until processing, inside boxes with plenty of water and oxygenation ensured by portable aerators. High densities inside the boxes were avoided thus preserving the good physical condition of the fish until they were returned to the aquatic environment. All specimens captured were identified down to the species level (if possible) and measured (total length). The length of the section to be sampled was not the same for the Ictiofauna PMC/PME and the Aquatic Ecosystems PM. In the first case, the INAG protocol (INAG, 2008) was strictly followed; in the second case, the length and duration of fishing followed the stipulated in the Lower Sabor’s Integrated Program of Environmental Monitoring (PIMA), in its 4th version, which consisted of the sampling of 50 m sections with an average depth of <1 m for 15 to 20 minutes.

Quality Control

All identificatons were performed by accredited technicians

Method steps

1. To be completed

The taxonomic coverage of this dataset spans 1 phylum, 1 class, 3 orders, 5 families, 13 genera and 14 species.

1. Animalia
   rank: kingdom
2. Chordata
   rank: phylum
3. Actinopterygii
   rank: class
4. Cypriniformes
   rank: order
5. Cyprinodontiformes
   rank: order
6. Perciformes
   rank: order
7. Cobitidae
   rank: family
8. Cyprinidae
   rank: family
9. Poeciliidae
   rank: family
10. Centrarchidae
    rank: family
11. Percidae
    rank: family

Data were collected along the lower Sabor river valley, from the mouth to the Maçãs river, about 70 km upstream, as well as in the Vilariça stream, in the municipalities of Torre de Moncorvo, Mogadouro, Macedo de Cavaleiros, Bragança and Vimioso.