"So does… the Vimba bream rather permanently populate Ems, Weser and Elbe. Here ... it can be found in Fulda and Werra in all seasons; … and in Weser along the whole length from the mouth to the beginning of the brackish water by Brake downwards" (Metzger, 1895). This, nowadays often forgotten character species of Weser, was and still is being mistaken for the common nase (Chondrostoma nasus). Vimba bream is a slow growing fish species. Spawning maturity occurs not until certain body fat content is achieved, and depends hence on food availability, temperature and nursery. Vimba bream requires the most diverse water structures for its various life phases. It uses the upper reaches for spawning and nursery of its fry.

Larval Vimba bream is reliant upon spatially closely located habitat structures, with zones of both strong and calm flow. Young Vimba bream migrate away from the spawning areas into the middle reaches of rivers, whereby the food availability and temperature determine the migration routes. The sexually mature individuals of Vimba bream perform spawning migration in autumn and spring. Hundreds of kilometers were proven to be covered thereby. Vimba bream is therefore reliant upon a functional water course continuity from the grayling region in upper reaches down to the bream regions in lower reaches.

Today, larger populations of Vimba bream can be found in upper Weser and Eder system. Interconnection of these habitats with Werra can provide a basis for the repopulation of Werra with Vimba bream.

Foto: Christoph Dümpelmann