In sorting, species determination and counting of selected taxa from the North Sea and the Baltic Sea, MariLim once more proved its high expertise.

In 2018, the Quality Assurance Authority of the German Marine Monitoring Programme for the North and Baltic Seas (BLMP) at the Federal Environment Agency (UBA) organized the 7th Macrozoobenthos Ring Test. Now, the final report is published.

The ring test was conducted between the end of August and the middle of October 2018 with 14 institutions processing 16 sample sets. From the North Sea, 12 small glasses with 21 pre-defined taxa had to be sorted out and determined. The Baltic Sea was represented by a Kautex bottle filled with sediment containing 11 taxa (156 individuals). This samples had to be rinsed and sorted, before the individuals found could be determined.

The aim of the ring test was to evaluate the performance, i.e. the sorting and counting accuracy as well as the taxonomic expertise of the participating institutions.

Members of the MariLim laboratory staff, Galyna Cherednichenko, Sandra Dittmer and David Johannes, processed these samples using 18 hours (generally the time frame is 10–20 hours). They determined the North Sea taxa with 98 % and the Baltic Sea taxa with 100 % accuracy; only one North Sea species was not correctly identified.

Regarding the Baltic Sea taxa, an overall assessment of the quantitative and qualitative performance was calculated by combining accuracy rates. MariLim belongs to the top 4 of all participants. Our laboratory team correctly determined all taxa. The counted numbers of individuals were within the pre-defined tolerance range.