Summary Our project deals with the role of zooplankton in the biological carbon pump in the southern ocean. Southern ocean stores more carbon than any other ocean area, and large part of this carbon storage happens through biological processes in so-called biological pump. Copepods - the abundant microscopic crustaceans that are the main predators of phytoplankton - play multiple roles in the biological pump, although we know very little of how their activities regulate the efficiency of carbon storage. We will investigate the distribution of copepods, the environmental factors that influence it and their role in the biological pump in the Southern Ocean - the key area for global carbon sequestration.