Antarctic Krill Ecosystem Services

Some new research reminds me how little we know about the natural world as we destroy yet another part of it. We had a rough idea about the importance of the Weddell Sea in locking up carbon through downwelling through our scientific partners at the University of Plymouth. The snow samples taken during the Antarctic Quest 21 expedition and analysed for metal concentrations contributed some data used to find out just how important that is to climate change mitigation.

New research by E Cavan et al and published in Nature Communications reveals another part of the same story: Antarctic krill sequesters around 20 megatons of carbon each season, which equates to billion of dollars of ecosystem services. This sequestration equals coastal ‘blue carbon‘, the sequestration of carbon by ecosystems, such as seagrass and seaweeds, mangroves and marshes.

Antarctic krill achieves this feat by their sheer numbers and even more numerous faecal pellets. Krill poop sink fast and is either incorporated into the sediment or transported by the deep Antarctic current – either way, it remains locked away for some hundred or more years.

Furthermore, Antarctic krill is also vital for the whole of the Antarctic ecosystem and global ocean health, as is the essential food source for penguins, fish, seals and whales. In turn, whales also contribute immensely to the fertility and carbon sequestration capacity of the ocean.

But Antarctic krill, Euphausia superba, is under threat:

• As rapid climate warming reduces Antarctic sea ice, and with it, the sea ice algae that are an important food source for larval krill.
• Krill fisheries are expanding, predominantly for the production of animal fodder and dietary supplements.

Can we afford to loose the ecosystem services of Antarctic krill?

Featured Image: Antarctic Krill. Part of the image “Antarktický krill” by Norkrill is licensed under CC BY-NC-ND 2.0  Creative Commons.