Remediation of Atlantic Sturgeon Acipenser oxyrinchus in the Oder River: Background and First Results

At the end of the nineteenth century, sturgeon populations in the southern Baltic Sea drainages started to decrease dramatically. The last captures were reported from Lake Ladoga in 1984 and off Estonia in 1996. Today, sturgeons are considered extinct or missing in the Baltic. In 1996, the pilot phase of a federally funded remediation program was initiated. In parallel, population genetic analyses of historic samples of the species were carried out at the IGB, revealing the succession of two different species in the Baltic Sea drainage area. As a result, broodstock development is being carried out using Canadian populations of A. oxyrinchus. The evaluation of habitat status for early life stages has been performed in the River Oder. Alternative fisheries techniques, based on by-catch data of exotic sturgeons, have been developed to increase juvenile survival upon release. Since 2006, experimental releases of juvenile A. oxyrinchus have been carried out annually to determine habitat use, migration patterns and risks for population development.