09-15-2025

Habitats for migratory fish: KU Floodplain Institute participates in EU project

Restoring and protecting the habitats of migratory fish species in the Danube and its tributaries – this is the goal of a large-scale European Union project involving scientific institutions, authorities, and government organizations from 18 countries. The KU Floodplain Institute is one of more than 40 project partners. With its expertise in floodplain and aquatic ecology, the research institute aims to make an important contribution to transnational cooperation and the development of sustainable solutions.

Migratory fish species are an essential part of biodiversity and contribute to the health of aquatic ecosystems. However, fish depend on intact habitats to migrate between spawning, feeding, and resting grounds. Human interventions such as the construction of dams and weirs have severely disrupted these natural migration routes. The EU research project SWIM (“Sustainable Water and Integrated Management of Fish Migration and their Habitats in the Danube River Basin and NW Black Sea”) aims to improve habitat connectivity. This means removing or overcoming physical barriers so that fish can migrate unhindered between their habitats.

Specifically, measures are planned such as the construction of fish ladders and the reconnection of river branches that were cut off by previous construction activities. The international project, which is scheduled to run for four years, is starting these days. The geographical focus is on the countries bordering the Danube up to its mouth, including Croatia, Serbia, Slovakia, and Romania. The project is funded by the Horizon Europe program as part of the EU mission “Restore our Ocean and Waters.” A total of around eight million euros is available to restore, protect, and improve the habitats of migratory fish species in the Danube basin and the northwestern Black Sea region. Thirteen pilot projects are being implemented at seven locations: in Czechia, Slovakia, Hungary, Romania, Ukraine, Serbia, and one project in Croatia, Bosnia and Herzegovina.

Floodplain Institute wants to network local partners

Close cooperation with local stakeholders is essential for the success of the measures, says Prof. Dr. Bernd Cyffka, head of the KU Floodplain Institute. “Involving local fishermen or municipalities in the development of measures is key to ensuring that the projects bring not only ecological but also social and economic benefits.” This enables sustainable implementation that enjoys long-term acceptance and support from the communities affected. The Aueninstitut Neuburg-Ingolstadt, which has already been involved in numerous EU-wide projects, intends to contribute its many years of experience in this area. A key contribution is the promotion of transnational cooperation within the framework of the SWIM Alliance, which intensifies the exchange between government agencies, NGOs, scientists, and local communities.

The focus is on active participation in pilot measures along the Danube and its tributaries, as well as the design and implementation of training and education programs. “These programs will be aimed at students, local authorities, and NGOs and will seek to deepen knowledge of water management and renaturation,” explains Cyffka. Through public relations work and knowledge transfer, the KU will also contribute to raising public awareness of the importance of these measures. The Catholic University will receive around 470,000 euros in funding within the SWIM project.

Technological innovations

Technological innovations will be used to implement the ecological measures. With the help of digital twins—virtual models of ecosystems—the project aims to simulate and optimize the effects of planned measures. In addition, the use of drones will enable precise monitoring of habitat conditions in real time. Blockchain-based data management systems will be introduced to facilitate cooperation with all relevant stakeholders and increase transparency. The use of virtual reality will also promote stakeholder engagement and education in the project.

The EU project aims to achieve long-term improvements in environmental policy. According to the project description, the project will not only directly improve the living conditions for migratory fish species, but also contribute to the achievement of the EU Biodiversity Strategy 2030, the Water Framework Directive, the Habitats Directive, and the European Green Deal. By integrating innovative technologies and taking into account the needs of local communities, SWIM has the potential to achieve significant progress in biodiversity conservation, ecological resilience, and socioeconomic well-being.