Mesozooplankton distribution and community structure in the Pacific and Atlantic sectors of the Southern Ocean during austral summer 2017/18: a pilot study conducted from Ukrainian longliners

Preliminary results of the pilot study of the mesozooplankton in the region between the Ross and Scotia Seas during November 2017 – April 2018 are presented. In total, 53 zooplankton samples were collected in the top 100 m water layer using vertical tows of the 0.1 m^-2 Juday net from four Ukrainian longliners operating during the Antarctic toothfish fishery. While providing basic information on the zooplankton density, distribution, community composition and seasonal dynamics, this pilot study emphasized the unique opportunity to investigate mesozooplankton dynamics in the regions traditionally not sampled during the oceanographic surveys. It also created unprecedented opportunities to increase the seasonal and geographical zooplankton sampling coverage at the fraction of the cost of the full scale oceanographic surveys. The potential of such surveys are enormous in both providing invaluable information, contributing to existing long-term data bases and enhancing an international collaboration in the Southern Ocean, particularly in light of recent modelling initiatives of the whole Antarctic system undertaken by the CCAMLR.