Barren depths from 82° N to the North Pole reveal scarcity of fish in the Central Arctic Ocean

Abstract The Arctic Ocean is changing from ice-covered to open water in summer, with boreal species expanding northwards. We conducted a ship-based marine ecosystem survey across the Eurasian Basin with pelagic trawling to the North Pole. Zooplankton biomass and abundances of capelin, Atlantic cod and other fish species were high in Atlantic Water along the continental shelf north of Svalbard. In contrast, no fish were caught in the lower epipelagic and mesopelagic layer (100- 500 m depth) north of 82 °N. This indicates that pelagic fishes are scarce in the Central Arctic Ocean, partly because of low zooplankton biomass. Seals and polar bears observed are likely sustained by the ice-associated food web, including ice amphipods and polar cod. As management advice, we suggest that the current fishing moratorium in the Central Arctic Ocean could be further developed into a marine protected area to conserve this unique Arctic biodiversity.