Background The Allis shad population in the Gironde watershed was the most important population in Europe until the beginning of the 21st Century with catches of several hundred tonnes/yr of fish. Since 2006 there has been a marked decline in the return rates of mature shads to the rivers for reproduction, the reasons for which are still not well understood. In 2008, a moratorium on Allis shad fishing was established in the Gironde watershed. One hundred years ago, the Allis shad population in the Rhine watershed was the most important shad population in its northern distribution range with annual catches of several hundred tonnes/yr of fish. Within 30 years this population collapsed. Reintroduction efforts were started in 2007 as part of a LIFE project (LIFE06 NAT/D/00005). Objectives The key objective of the project is the re-introduction of Allis shad to the Rhine watershed. In a unique European approach the project is combining the conservation of the largest remaining Allis shad population in Europe in the Gironde watershed in France with the re-introduction of Allis shad to the Rhine watershed in Germany. Another key objective of the project will be the transfer of Allis shad aquaculture techniques from France to Germany and the development of techniques for an ex-situ stock. These are important conservations tools for diadromous fish restoration and have been implemented in recovery plans of the European sturgeon and Atlantic salmon. A pilot ex-situ facility will be established in Germany and mature or nearly mature fish can be expected at the end of the LIFE+ project. The development of these techniques will enable the project to remove fewer fish from French rivers and to include returning fish to the Rhine watershed in the ex-situ stock in the future. In addition these techniques can be used in other European watersheds where Allis shad populations are in danger. The following actions will be carried out: Analysis of the potential bottlenecks for Allis shad in the Gironde watershed, river connectivity and reproduction success, and the improvement of the situation thanks to the results of these studies; Re-defining the Allis shad fish pass design in Europe in the light of the latest knowledge and improvements coming from US Shad fish passes. These improvements will be implemented in the Gironde watershed; Stocking of 1.5-2 million Allis shad larvae per year in the years 2011-15 resulting in a total number of 7.5-10 million shad larvae within the duration of the project; Monitoring of the expected increase in the return rates of mature Allis shad in the Rhine watershed from 2013 onwards; Development of the techniques for an Allis shad ex-situ stock in France and Germany and the installation of a pilot facility in Germany close to the Rhine; and Transfer of knowledge of Allis shad aquaculture from France to Germany. Reintroduction programmes of the closely related American shad stock show that around 250 Allis shad larvae are required to obtain one returning adult. Therefore 30 000-40 000 Allis shad can be expected from a stocking of 7.5-10 million shad larvae. Expected results: An increase in the return rates of mature shad to the Rhine watershed from 2013 onwards; Improvement of the migration possibilities in the Gironde watershed; Installation of an ex-situ pilot facility in Germany with an output of 50 mature or near mature Allis shad in 2015; Technical publications on Allis shad aquaculture with special emphasis on the development of an ex-situ stock, state-of-the-art fish pass design and monitoring techniques; and Increased public awareness of the conservation and restoration of Allis shad in Europe through aquarium exhibitions, information panels, events, Allis shad festivals and school programmes.