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.
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Data availability
Data are available at the Norwegian Polar Data Centre (https://data.npolar.no). Hydrographic data from the 2022 expedition63 are at https://doi.org/10.21334/NPOLAR.2022.D1E609E2 and from the 2023 expedition64 at https://doi.org/10.21334/NPOLAR.2024.7B5B8509. Acoustic data, as Nautical Area Scattering Coefficients from the 2022 expedition65, are available as https://doi.org/10.21334/NPOLAR.2026.4BAF76DC, and from the 2023 expedition66, as https://doi.org/10.21334/NPOLAR.2026.80EF9A81. Zooplankton data are available at: https://doi.org/10.21334/NPOLAR.2026.87CEB0C1.
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Acknowledgements
We thank the captains and crews of RV Kronprins Haakon and Le Commandant Charcot (2022). Thanks to Dmitry V. Divine (NPI) for recording sea-ice conditions during our expeditions, and to Victoria Eggen and Juni Bjørneset for assistance in the fish lab. Figures were produced from data using built-in functions of the MATLAB programming language plus the “M_map” mapping package for MATLAB maintained by R. Pawlowicz. The expeditions were supported by the Norwegian Ministry of Foreign Affairs, the Fram Centre project Sustainable Development of the Arctic Ocean (SUDARCO), the RCN Bottom Sea ice Respiration and nutrient Exchanges Assessed for THE Arctic (BREATHE) project, the flagship Fram Centre project SUDARCO, and the Norwegian Polar Institute.
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O.A.M., P.A.D. and A.N. led the 2022 research cruise, collected and interpreted oceanographic data and contributed with figures and text edits. H.H., A.W., and O.A.M. led the 2023 research cruise, where H.H. and O.A.M. collected fish samples and A.W. collected zooplankton. M.A.G. collected and interpreted oceanographic data and contributed text edits. V.S. assisted with biological samples and organized data. R.K. and O.A.M. interpreted hydroacoustic data and edited text. H.H. and O.A.M. drafted and edited the text with input from all co-authors.
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Supplementary material to “Barren depths from 82°N to the North Pole reveal scarcity of fish in the Central Arctic Ocean”
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Dodd, P.A., Hop, H., Nikolopoulos, A. et al. Barren depths from 82° N to the North Pole reveal scarcity of fish in the Central Arctic Ocean. Commun Earth Environ (2026). https://doi.org/10.1038/s43247-026-03381-7
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DOI: https://doi.org/10.1038/s43247-026-03381-7
