@misc{boersma2017maat, author={Maarten {Boersma} and Wulf {Greve} and Jasmin {Renz} and Ursula {Ecker} and Inga V {Kirstein}}, title={{Mesozooplankton abundances at time series station Helgoland Roads since 1974}}, year={2017}, doi={10.1594/PANGAEA.873032}, url={https://doi.org/10.1594/PANGAEA.873032}, organization={Alfred Wegener Institute - Biological Institute Helgoland}, abstract={In 1974 the determination of zooplankton was added to the Helgoland Roads long-term data series. Zooplankton was sampled with an oblique haul using a 150$\mathrm{\mu}$m hand net at the "Kabeltonne" site (54{\textdegree}11.3${'}$N, 7{\textdegree}54.0${'}$E). Live samples were counted with a stereomicroscope until 1981, since then samples are preserved in 4{\%} formaldehyde (buffered with Borax) to allow for storage and later examination. Samples are counted depending on the density either as whole or subsamples. However, at least 60 individuals of each key species are counted per subsample to ensure counting of a representative part of the sample. This data collection includes mesozooplankton abundances since 1974 until present. Data of meso- and macrozooplankton abundances collected with a 500$\mathrm{\mu}$m Calcofi net since 1975 are available in Renz et al. (2018).}, type={data set}, publisher={PANGAEA} }