The main objective of this project is related with the implementation and monitoring of the plan defined for the capture and translocation of fish specimens associated to the construction and operation of the Foz Tua hydroelectric dam. This plan aims to reduce the barrier effect caused by the construction of the Foz Tua dam, allowing to maintain the genetic flow of fish populations occurring within the study area, especially the potamodromous ones, like the Iberian barbell (Luciobarbus bocagei Steindachner, 1864) and the Northern Iberian nase (Pseudochondrostoma duriense Coelho, 1985), between the area located downstream of the Foz Tua dam and the area upstream of this obstacle, in river Tua and respective tributaries. Specifically, this project includes four different tasks: i) manual capture and translocation of Iberian barbell and Northern Iberian nase from downstream to upstream of Foz Tua dam; ii) manual capture and translocation of Iberian barbell and Northern Iberian nase from upstream to downstream of Foz Tua dam; iii) monitoring of Iberian barbell behaviour downstream of Foz Tua dam using acoustic telemetry; and iv) monitoring of Iberian barbell behaviour upstream of Foz Tua dam using acoustic telemetry.