Materials collected in the Arctic Ocean include two general zones of drifting sea ice cover: the Transpolar Drift Stream and the Beaufort Sea Gyre. Large scale sampling was very important for an understanding of the biogeographical zonation and distribution of the sea ice biota. To understand the features of the biological processes in the sea, the seasonal observations were carried out within the main ice drifting system over two summer seasons (NP-22, 1975 and NP-23, 1977) and one winter season (NP-22, 1980). Both summer and winter seasons were concluded by the observations in spring at the same "North Pole" stations. Thus, the materials cover three annual cycles: 1975-1976 (NP-22), 1977-1978 (NP-23), and 1980-1981 (NP-22).