Connect Fish Concludes Its research core topic Tools core topic Determine the Future of Dams in Spain

TheConnect Fish research project has come to a close after providing new insights and tools to address one of Spain’s major environmental challenges: reconciling freshwater fish conservation with river management . In a country that is home to more than 70% of Europe’s endemic freshwater fish species and has one of the highest densities of dams in the world, river connectivity has become a core topic biodiversity.

In this context, Connect Fish has been developed as a multidisciplinary initiative multidisciplinary at assessing the impact of cross-cutting barriers—dams and weirs—from both ecological and social perspectives. Its findings are in line with the National Strategy for River Restoration, which promotes, among other measures, the removal of obstacles to restore river connectivity.

 “We need to combine scientific evidence with communication and social engagement strategies— core topic moving toward management river management in Spain,” says David Galicia, researcher the BIOMA Institute at the University of Navarra.

Among the key achievements of this project the creation of the database , the most comprehensive inventory to date of obstacles in Spanish rivers. This inventory is organized within a digital platform based on the spatial structure of river networks, providing an framework for analyzing river connectivity from a network perspective network facilitating its application to the management restoration of aquatic ecosystems. In addition, the team has developed distribution models for 44 native fish species, identifying their environmental needs and determining potential habitat areas.

The project has project developed specific connectivity indices for potamodromous species (species that migrate between different sections of the same river) and has conducted programs of study in river basins such as the Deva-Cares and Bidasoa. In the case of salmon, the analyses highlight the direct impact of barriers on the medium- and long-term population trends of this species.

Analyses confirm that man-made barriers significantly reduce habitat quality for many species. Thanks to the tools that have been developed, it is now possible to identify which infrastructure has the greatest negative impact and prioritize actions such as its removal or adaptation.

The project incorporated aspects such as public perception of dams and river restoration into its assessment the impact of river barriers. In this regard, although there is some general support for the removal of barriers, this support diminishes when the infrastructure has recreational or scenic value. Furthermore, certain groups express reservations related to the loss of traditional uses, which underscores the importance of involving the public in decision-making processes.

“Incorporating the voices of those who live in a given area is essential for good environmental governance. In river landscapes, as in any other, many different types of values are intertwined that we must take into account, and we can only learn about some of them by asking the people who have a close relationship with the ecosystem in question,” says Ana Villarroya, a researcher at the BIOMA Institute.

Connect Fish was a project by the Biodiversity and Environment Institute ) at the University of Navarra in partnership the Institute of Environmental Hydraulics at the University of Cantabria, and has received support from the Biodiversity Foundation of the Ministry for Ecological Transition and the challenge (MITECO) within the framework Recovery, Transformation, and Resilience Plan (PRTR), funded by the European Union—NextGenerationEU.