Background The project site is the fluvial corridor of the Po river and the plain area of Italy’s largest watershed (over 70 000 km2). The area is home to the 11 European priority fish species and more than 40 native fish species, 15 of which are endemic or sub-endemic to the area. Fish species of European interest are the same from the river’s mouth up to 400-500 km upstream. Threats to the species are the fragmented ecosystem (e.g. the links with Serafini Island) and the scattered management system of the area. The wide zone frequented by protected fish species falls under the jurisdiction of four regions and 15 provinces, and comprises many protected fluvial Natura 2000 network sites and just as many management entities. As a result, the common fish conservation targets clash with the diverse range of local interests. Conservation measures are urgent owing to the high risk level: two native species of sturgeon, for example, have already become extinct in the project area. Objectives The main objectives of this project are: To conserve the Adriatic surgeon (Acipenser naccarii), an anadromous migratory fish species that is endemic to the fluvial basin bordering the upper Adriatic Sea; To conserve all native fish species (10 of which are listed in Annex II of the Habitat Directive) of the lower-middle Po river and the connected hydrographical basin; To reduce fluvial habitat fragmentation; and To increase networking among local authorities and improve communal and shared governance of the large area targeted by the project. The core project actions will involve the building of fish passes, the reintroduction of Acipenser sturio, and reinforcement of Rutilus pigus, Barbus plebejus, Chondrostoma soetta and C. genei, and the removal of invasive alien species. Expected results The main quantifiable expected results are: Building of infrastructure allowing fish upstream passage in the Po at Isola Serafini, some 300 km from the river delta; Establishment of a coordination committee that includes representatives from all of the regional and inter-regional administrations; An increase in the population of the Adriatic sturgeon and other fish species via the reintroduction of more than 200 000 individuals; Creation of a shelter for educational activities at Isola Serafini; and Building of a footpath connecting the passage points.