Abstract

A summer study of zooplankton in the Fram Strait area of the Greenland Sea showed elevated abundances of herbivorous copepods in the marginal ice zone or ice-edge compared with copepod communities under the pack ice cover. Several physical factors contributed to this, including the large-scale current systems which deliver both North Atlantic and Arctic plankton to the ice-edge and the effect of melting ice and eddies in increasing primary productivity and standing stocks of phytoplankton. The potential importance of the ice-edge in secondary production was observed directly as increased numbers of juvenile copepods. Indirectly, it can be inferred from observations that copepods under ice-cover were ingesting only enough to meet daily metabolic demands, were metabolizing protein, and were not storing lipid. Copepods were not undertaking diel vertical migration. Abundances of female copepods at the ice-edge were largely a function of currents, while growth of juveniles was dependent on food supply which even at the ice-edge fell short of the calculated requirements of the dominant copepods.

Share

COinS