Netherlands Polar Data Center

Project - The imperiled role of sea ice in supporting the living resources of the polar oceans (Iceflux-NL)


Polar sea ice habitats are changing drastically, and are predicted to decline significantly in both hemispheres during the 21st century. Changes in sea ice are crucial, because ice algal production provides a key carbon source during critical periods of the year. Ecological key species dwelling at the ice underside, such as Antarctic krill Euphausia superba and Arctic cod Boreogadus saida constitute a trophic bottleneck in the transfer of ice algal carbon into polar marine ecosystems. Sea ice decline will change the abundance and distribution of such key species, likely affecting populations of seabirds and mammals as well as the potential for human exploitation. With the present proposal we aim to quantify the association of krill and other key species with under-ice habitats during different seasons, in order to develop robust statements on the impact of sea ice decline on polar marine resources and conservation objectives. This will be achieved by quantitative sampling under-ice fauna with a new under-ice trawl developed by Wageningen Marine Research (former IMARES). We plan participating in a winter and a summer expedition in Antarctica, and in an expedition in the Arctic. Investigations comprise analyses of the population structure and the diet of ecological key species, and comparisons with their distribution in open water and deeper water layers. A close collaboration with the Helmholtz Young Investigators Group Iceflux at the German Alfred Wegener Institute ensures the embedding of our results in multidisciplinary research on trophic carbon flux in sea ice systems, and bio-physical modelling of sea ice habitats.

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Fokje L. Schaafsma, Yves Cherel, et al., 2018. Review: the energetic value of zooplankton and nekton species of the Southern Ocean. Marine Biology 165 (8), 129

Susanne Kühn, Fokje L. Schaafsma, et al., 2018. Plastic ingestion by juvenile polar cod (Boreogadus saida) in the Arctic Ocean. Polar Biology 41 (6), 1269-1278

Kohlbach, D, Lange, B.A., et al., 2017. Ice Algae-Produced Carbon Is Critical for Overwintering of Antarctic Krill Euphausia superba. Frontiers in Marine Science 4

Schaafsma, F. L., Kohlbach, D, et al., 2017. Spatio-temporal variability in the winter diet of larval and juvenile Antarctic krill (Euphausia superba) in ice-covered waters. . Marine Ecology Progress Series

Kohlbach, D, Schaafsma, F. L., et al., 2017. Strong linkage of polar cod (Boreogadus saida) to sea ice algae-produced carbon: Evidence from stomach content, fatty acid and stable isotope analyses. Progress in Oceanography 152, 62-74

David, C, Schaafsma, F. L., et al., 2017. Community structure of under-ice fauna in relation to winter sea-ice habitat properties from the Weddell Sea. . Polar Biology 40 (2), 247-261

Schaafsma, F. L., David, C, et al., 2016. Size and stage composition of age class 0 Antarctic krill (Euphausia superba) in the ice-water interface layer during winter/early spring. . Polar Biology 39 (9), 1515-1526

David, C, Lange, B.A., et al., 2016. Under-ice distribution of polar cod Boreogadus saida in the central Arctic Ocean and their association with sea-ice habitat properties. . Polar Biology 39 (6), 981-994