Investigation on the possible improvement of the re-stocking strategy as well as scientific monitoring of the eel re-stocking program at the Baltic Sea coast of Schleswig-Holstein
Funded by the LLUR Schleswig-Holstein
Foto: UHH/CeNak, Kullmann
The European eel has an outstanding socio-economic importance. However, since the 1980s the landings decreased dramatically and the recruitment stagnates at a historic low level. By now the European Union requests its member states to establish measures aiming at the recovery and sustainable use of the eel stock.
In this regard re-stocking is an important management measure: the selective release of caught young eels in certain water systems. On the one hand eels are released directly as most recently caught glass eels (6-7 cm) and on the other as pre-grown farm eels (20-30 cm).
The efficiency of both strategies is unknown for coastal waters. Therefore, the Department Ichthyology of the Center of Natural History carries out a research project aligned accordingly. Financial support comes from the State Agency of Agriculture, Environment and Rural Areas (LLUR) of Schleswig-Holstein. The aim of this study is to evaluate possible differences in growth rate and body condition between glass and farm eels that were stocked in the Schlei and the waters of the Baltic Sea coast of Schleswig-Holstein. To identify the best re-stocking strategy all eels will be marked chemically prior to stocking. Growth rate and other parameters will be determined and compared between both stocking sites and forms (glass and farm eel) after their re-catch.
Publications
- Kullmann, B., Adamek, M., Steinhagen, D. & Thiel, R. (2017): Anthropogenic spreading of anguillid herpesvirus 1 by stocking of infected farmed European eels, Anguilla anguilla (L.), in the Schlei fjord in northern Germany. Journal of Fish Diseases 40 (11): 1695-1706.
- Kullmann, B., Hempel, & Thiel, R. (2018): Chemical marking of European glass eels Anguilla Anguilla with alizarin red S and in combination with strontium: in situ evaluation of short-term salinity effects on survival and efficient mass-marking. Journal of Fish Biology (92 (1): 203-213.
- Kullmann, B., Neukamm, R. & Thiel, R. (2017): Mass-marking of farmed European eels (Anguilla anguilla (Linnaeus, 1758)) with Alizarin Red S. Journal of Applied Ichthyology 33 (5): 914-917.
- Kullmann, B. & Thiel, R. (2018): Bigger is better in eel stocking measures? Comparison of growth performance, body condition, and benefit-cost ratio of simultaneously stocked glass and farmed eels in a brackish fjord. Fisheries Research 205(18): 132-140.