Abstract
Sorting centers are important for processing material collected during extensive oceanic expeditions. Based on information obtained from samples of appendicularians, this paper demonstrates that usual procedures adopted in sorting centers produce samples which contain only a fraction of the organisms present in the original catch (or subsample). In addition, the proportion of individuals sorted varies considerably. In four “Indian Ocean Standard Net” catches collected in the Arabian Sea, subsamples (called “sorted samples” in this paper) are compared with careful microscopical counts (“quantitative counts”) performed by the author. The numbers of appendicularians found in quantitative counts were 2.4 to 19.2 times higher than those in the sorted samples. Sorting efficiency varies in different forms of appendicularians; it is particularly low in Fritillaria sp. Bad preservation and small body size further reduce the portion sorted out. Under certain conditions (e.g. net clogging), numerous small appendicularians are retained which normally would pass easily through the meshes of the plankton net.
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Bückmann, A.: Untersuchungen über das Macroplankton bei Ischia und Capri und im Golf von Neapel im Mai 1962. III: Die Appendicularien. Pubbl. Staz. zool. Napoli 35, 215–238 (1967).
—: Die Verbreitung der Kaltwasser- und Warmwasserfauna der Appendicularien im nördlichen Nordatlantischen Ozean im Spätwinter und Spätsommer 1958. Mar. Biol. 5, 35–56 (1970).
—: Die Appendicularine von den Fahrten der „Meteor”, der „Anton Bruun” und der „Discovery” aus dem Arabischen Meer im Rahmen der IIOE. “Meteor” ForschErgebn. (D) 10, 1–45 (1972).
— und H. Kapp: Untersuchungen am Zooplankton von der atlantischen Kuppenfahrt der „Meteor”, März bis Juli 1967. “Meteor” ForschErgebn. (D) 13, 11–36 (1973).
Fol, H.: Nouveau genre d'appendiculaires. Archs Zool. exp. gén. 3, 1–18 (1874).
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Communicated by O. Kinne, Hamburg
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Bückmann, A. Sorted samples and quantitative counts in appendicularian catches. Mar. Biol. 21, 349–353 (1973). https://doi.org/10.1007/BF00381092
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DOI: https://doi.org/10.1007/BF00381092