20 September 2023 news

By Benjamin Merkel, Akvaplan-niva

Antarctic krill and Ice krill are key species within the Southern Ocean. They are important prey for marine predators such as the big baleen whales as well as seals, seabirds, and penguins. In turn they are important grazers of plankton and hence essential for the energy flow and nutrient cycling in the Southern Ocean. Antarctic krill is also the focus of a modern fishery.

Given their ecological and economic importance, it is necessary to gain an understanding of the global distribution of krill. A new study took advantage of new and improved estimates of the Antarctic marine environment to model the austral summer global habitat of both Antarctic krill and Ice krill. Through the use of these models were able to show the distinct habitats of both species. Antarctic krill can mainly be found in the open ocean and concentrated in the Atlantic sector of the Southern Ocean covering an area the size of Australia, while Ice krill habitat was concentrated more evenly around the continent, largely over the continental shelf in an area roughly the size of Iran.

Krill comparison map (Credit: Benjamin Merkel/Akvaplan-niva).

The new study is a collaboration between Akvaplan-niva, the Norwegian Polar Institute, the Alfred Wegener Institute, and the British Antarctic Survey and the results are published in the ICES Journal of Marine Science (https://doi.org/10.1093/icesjms/fsad110). Knowledge about potential areas where these krill species can be found is essential to develop spatial planning solutions that aim to conserve biodiversity, minimize risk associated with climate change, and help retain species both now and into the future. This study has been developed as part of a process to establish a marine protected area in the eastern Weddell Sea outside Dronning Maud Land, Antarctica. This process is led by the Norwegian Polar Institute.