This 35-minute documentary highlights the key areas and research questions of our project, explains and documents the fascinating work involved in this spectacular field study, and highlights the hurdles and obstacles faced by migratory river fish. As part of the ‘European Tracking Network’, this project has also attracted international attention; the tagging of hundreds of fish can provide further data and insights which could point to healthier biodiversity in Swiss rivers despite rising temperatures. (documentary in Swiss German language)