UAF - Arctic Ocean Chuckchi Sea August 1953-1954 Zooplankton vertical stratified collections on board of the Russian R/V Lomonosov, program ANII A-65

Zooplankton collections were made to investigate interannual changes in species composition, abundance and distribution of the zooplankton in the Chuckchi Sea, one of the biologically lesser known areas of the Arctic. Vertical stratified tows (0-10 m, 10-25 m and 25 m bottom) were done with a Nansen net (0.5 m diameter, 333 µm mesh) at 21 stations in August of 1953 and August of 1954. The ship that was used is R/V/ Lomonosov; geo-referencing of stations was done. Temperature, salinity and oxygen concentrations were measured at each depth layer. Total zooplankton abundance and biomass in the southern Chuckchi Sea were dominated by North Pacific species (e.g. Metridia pacifica, Eucalanus bungii, Neocalanus plumchrus) and they were higher in 1954 then in 1953, indicating a substantial push of the Bering Sea water onto the Arctic shelf. Specifics of fieldwork in the Russian waters in the mid-1950 and translation issues between cyrillic and English spellings should be considered when analyzing these data.