The zooplankton community in the vicinity of the ice edge in the west central Weddell Sea was investigated in the late austral summer (March 1986). Sampling was done with two ships operating concurrently, one in the pack ice and the other in the adjcent open sea. Metazoan microzooplankton (<1 mm) was most abundant in the epipelagic zone. It consisted mostly of copepod nauplii and copepods of the generaOithona, Oncaea, CtenocalanusandMicrocalanus. While species composition was similar in both areas, vertical patterns differed in that the microzooplankton had sparse populations in the upper 50 m under the ice. This may have been related to water temperature which in the upper 50 m under the ice was more than 1°C cooler than in the open sea. Zooplankton in the 1–20 mm size range was dominated by the calanoid copepodsMetridia gerlachei, Calanus propinquusandCalanoides acutuswhich constituted half the biomass in the upper 1000 m. Their populations had highest densities in the upper 150 m, though much of theC. acutuspopulation resided below 300 m.Metridia gerlacheiandC. propinquusunderwent diel vertical migrations in both areas whereasC. acutusdid not migrate. Species diversity in the epipelagic zone was moderate and the fauna was characterized by species typical of the oceanic east wind drift. Diversity increased with depth and was due primarily to the appearance of circumpolar mesopelagic copepods in Weddell Warm Deep Water. Biomass of 1–20 mm zooplankton in the 0–1000 m zone was low (1.1–1.3 gDWm-2) compared to other Southern Ocean areas investigated with comparable methods. It is suggested that this is related to Weddell circulation patterns and the resulting low annual primary production in the central Wed
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