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Abstract

For each of the most representative taxonomic groups in the fresh-water zooplankton one or more species were cultured in the laboratory. The potential growth of the different species populations were compared by determining their intrinsic rate of natural inscrease under defined laboratory conditions. The highest value of intrinsic rate was found for the rotifer Brachionus falcatus, and the lowest value was for the calanoid copepod Argyrodiaptomus furcatus. Such values closely reflected the differences in the life-cycles of these organisms. The maximum yield both in density as well as biomass was obtained for Rotifera and Ciliophora. They reached densities of 300,000 ind./l and 1,000,000 ind./l respectively and corresponding biomass of 480 mg PS/l and 80 mg PS/l. For the microcrustaceans the yield was much smaller, around one order of magnitude lower for Cladocera and two for Copepoda.