A Stempel pipette has been used for subsamples in taxonomic analysis of zooplankton. Taxonomic identification has been done at the Institute of Oceanography by I. Siokou-Frangou and E. Christou with use of relevant taxonomic literature. Mesozooplankton biomass was estimated as dry-weight (mg/m**3) according to M. Omori and T. Ikeda (Methods in Marine Zooplankton Ecology. New York, John Wiley & Sons. 1984. 311 p.) (1984). A Folsom splitter has been used for biomass and abundance estimations in 4% formaldehyde buffered sub-samples.