From an environmental point of view, reservoirs present pros and cons. They provide water for human consumption and land irrigation, electrical power, leisure activities and some of them could even be rated as historical heritage. However, they present problems related to sedimentation, fracture risks, they interrupt biota in rivers and therefore also interrupt the flow of migrating species. A European project, led by the University of Oviedo in Spain, will conduct research to study the positive and negative effects of reservoirs in order to solve problems and get the greatest benefits.

The AMBER project, which stands for Adaptative Management of Barriers in European Rivers, is financed by European funds with more than 6 million euros and it is to be finished in 48 months. Its implementation will start on June 1 this year. 19 institutions from 12 European countries, coordinated by the University of Swansea, in Wales, collaborate in the development of the project. The University of Oviedo will be in charge of leading the two cases under study in the Iberian Peninsula. Researchers will analyze the Almanzora River in Málaga, as an example of the Mediterranean basin. The academic institution will collaborate in both analyses with the Spanish NGO AEMS-Ríos con Vida.

The Asturian scientists will determine, ten years after the first studies were performed, if in the case of Alto Nalón, exotic trout dominate native trout

Professor Eva García Vázquez, Professor of Department of Functional Biology of the University of Oviedo points out that, parallel to the development of both case studies, the Asturian researchers will design a molecular kit based on environmental DNA to evaluate the relation between fish populations, invertebrates or algae in rivers, and also to detect invasive species from water samples.

In addition, the lecturers of the University of Oviedo will participate in the elaboration of an inventory of reservoirs in the Iberian Peninsula and will develop a socio-educational research method, says Eva García Vázquez, aimed at achieving feedback from the society about reservoirs, their utility, advantages and disadvantages and improvement possibilities. All these actions will be developed taking into account people that live in areas close to these reservoirs.

Collaboration with fishermen

The first contact took place last Saturday with a group of fishermen from Alto Nalón who were asked to collaborate to collect scale samples taken from the back parts of fish especially trout, which will be subject to DNA tests.

Professor Eva García Vázquez explains that, in the particular case of Spain, Alto Nalón has been chosen because it has two reservoirs that are representative of the Atlantic basins: Tanes and Rioseco, because they also have protected areas like the Redes National Park, the conservation of their natural resources, especially the native trout, and the design of a new reservoir in the area of Caleao.

This researcher also explains that in Asturias, we are starting to have several problems resulting from the introduction of the trout imported from Germany. Studies developed prior to the AMBER Project determined that after analyzing the DNA of 3.000 individuals without having to kill any of them, trout coming from Germany showed a better adaptation to quiet water than the native trout, so they grouped together in reservoirs. They also found that native and imported lineages can hybridize. Researchers aim to find out what happened ten years after the first studies were performed "Does exotic lineage gain ground to native lineage? What´s the impact on the reservoir? These are some of the questions that we want to make clear with this new study", explains the researcher. In addition to the trout, the AMBER Project will also give researchers the opportunity to study, in the case of Asturias, other species living in reservoirs and upstream;for example, reserachers may verify if there are any eels (Anguilla anguilla), or exotic species like rainbow trout (Oncorhynchus mykiss), carp (Cyprinus carpio), or "bordallo" (Squalius carolitertii).

Cover picture: Rioseco reservoir, transferred by researchers.