Abstract

The production of Antarctic krill oil is a large industry and is predicted to grow in the coming decades. Understanding how Antarctic krill lipids (oils) change in time and space is therefore of critical importance to maintaining a sustainable krill fishery. This study examined how the lipid and fatty acid content of Antarctic krill varies seasonally and spatially. We used samples of krill harvested by krill fishing vessels collected daily over a 3-year time period. Krill were staged, sexed, weighed and measured before undergoing lipid analysis. Our results show an annual fine-scale seasonal cycle for lipid content and composition in Antarctic krill. Levels of the ecologically and commercially important and health-benefitting omega 3 polyunsaturated fatty acids varied between seasons, giving us an enhanced insight into variations in the krill diet and health throughout the year. Our data can be used as a baseline for future studies assessing lipid levels under stressors such as ocean acidification and warming. These results also serve as a baseline for lipid levels in the energy budget of krill throughout their life history and between the sexes.