Use constraints: Data can be used freely given that the source is cited (following creative commons license CC-BY). The source should be cited as: “HELCOM HOLAS 3 Dataset (2023)"

The data are provided by national monitoring programmes with HELCOM COMBINE parameters and methods. The indicator is based on routine data obtained within current monitoring schemes in the Baltic Sea, and is applicable in all areas where the programme is implemented. All HELCOM Contracting Parties carry out relevant monitoring.

The indicator uses mean zooplankton size and total stock (MSTS) for evaluating whether good environmental status is achieved or not. The indicator uses the parameter mean zooplankter size (mean size) which is presented as a ratio between the total zooplankton abundance (TZA) and total biomass (TZB). This metrics is complemented with an absolute measure of total zooplankton stock, TZA or TZB, to provide MSTS. Thus, MSTS is a two-dimensional, or a multimetric, indicator representing a synthetic descriptor of zooplankton community structure. The overall confidence of the evaluation is moderate to high and varies between assessment units.

Additional information:

http://www.helcom.fi/baltic-sea-trends/indicators/zooplankton-mean-size-and-total-stock-(MSTS)/