Copepods collected along 33.5゜E longitude of the Antarctic Ocean in the 1976 summer

Abstract

Zooplankton samplings were conducted at 6 stations along 33.5°E in the Indian sector of the Antarctic Ocean from 25 February to 2 March in 1976 by the 17th Japanese Antarctic Research Expedition. Vertical hauls from a depth of 200m to the surface with a Norpac net (45cm in diameter, 0.33mm mesh openings) were carried out. Copepoda occupied more than 85% of the total individual numbers of zooplankton at all stations. The species composition and abundance of copepods were investigated. A total of 18 species except for Oncaeidae were identified. Calanus propinquus, Calanoides acutus, Rhincalanus gigas, Ctenocalanus vanus, Scolecithricella glacialis and Oithona similis were found commonly at almost all stations. Miclocalanus pygmaeus, Lucicutia sp., Haloptilus ocellatus, Haloptilus oxycephalus and Metridia gerlachei occurred south of 60°S and Calanus simillimus, Clausocalanus laticeps, Metridia lucens and Oithona frigida occurred north of 60°S. Euchaeta antarctica, Racovitzanus antarcticus and Heterorhabdus austrinus occurred sporadically and/or in small number.