Lipid composition and trophic relationships of krill species in a high Arctic fjord
- 499 Downloads
Our study deals with the lipid biochemistry of the krill community in the ecosystem of the high Arctic Kongsfjord (Svalbard). During the last decades, Kongsfjord experienced a change in krill species composition due to recent increased advection of Atlantic water masses carrying characteristic boreal as well as subtropical-boreal euphausiids into the ecosystem. The lipid biochemistry and trophic relationships of the species recently inhabiting the Arctic water masses are scarcely known, although a change in a krill population may have a significant impact on the ecosystem. A comparison of nutrition and energy storage strategies, stable isotopes, lipid profiles and fatty acid compositions showed remarkable differences between the krill species. These reflected the diverse feeding behaviours and specific adaptations to the environments of their origin: the boreal Meganyctiphanes norvegica and subtropical Nematoscelis megalops appear more carnivorous and have significantly lower mean lipid contents (29 and 10 %, respectively) and a different energy storage pattern (triacylglycerols and polar lipids, respectively) than the arcto-boreal Thysanoessa inermis, which consists of up to 54 % of lipids mainly stored as wax esters (>40 %). These differences may have significant implications for the rapidly changing marine food web of Kongsfjord—especially for higher trophic levels relying on the nutritional input of animal lipids.
KeywordsEuphausiids Fatty acids Kongsfjord Lipid classes Meganyctiphanes norvegica Nematoscelis megalops Stable isotopes Thysanoessa spp.
We thank the captain, the crew and the scientists including the chief of AREX2012 on-board RV Oceania for their great hospitality and assistance during sampling. For the same, we thank the captains of the Kings Bay AS workboat MS Teisten. We are very grateful for the professional support by the AWIPEV station leaders and (logistic) engineers, Ny-Ålesund, Spitsbergen. We thank Prof. Dr. Wilhelm Hagen, Petra Wencke and colleagues from BreMarE—Centre for Research & Education (University of Bremen, Department Marine Zoology, Germany) for the use of their facilities and help in lipid extraction. We are grateful to Dieter Janssen, Stefanie Baßler, Mandy Kiel and Ruth Alheit for their skilful assistance in lipid analyses at the AWI laboratories, Bremerhaven. Furthermore, we thank R. Alheit for the final language edit as a native speaker. Special thanks to Prof. Dr. Michael Greenacre (Universitat Pompeu Fabra, Barcelona) for the detailed advice on the statistical analyses; and thank you for the music. This work was supported by the French–German AWIPEV project KOP 124_1-5, RIS ID 3451. NE-Atlantic samples were obtained under the EU-FP7 project EURO-BASIN and from the Benguela current under BMBF-GENUS, 03F0497F, Germany.
- Auel H, Harjes M, da Rocha R, Stübing D, Hagen W (2002) Lipid biomarkers indicate different ecological niches and trophic relationships of the Arctic hyperiid amphipods Themisto abyssorum and T. libellula. Polar Biol 25:374–383Google Scholar
- Berkes F (1976) Ecology of euphausiids in the Gulf of St. Lawrence. J Fish Res Board Can 33:1894–1905Google Scholar
- Boyd SH, Wiebe PH, Cox JL (1978) Limits of Nematoscelis megalops in the northwestern Atlantic in relation to Gulf stream cold core rings. II. Physiological and biochemical effects of expatriation. J Mar Res 36:143–159Google Scholar
- Einarsson H (1945) Euphausiacea. I. Northern Atlantic species. Bianco Luno, CopenhagenGoogle Scholar
- Falk-Petersen S, Gatten RR, Sargent JR, Hopkins CC (1981) Ecological investigations on the zooplankton community in Balsfjorden, Northern Norway: seasonal changes in the lipid class composition of Meganyctiphanes norvegica (M. Sars), Thysanoessa raschii (M. Sars), and T. inermis (Krøyer). J Exp Mar Biol Ecol 54:209–224CrossRefGoogle Scholar
- Falk-Petersen S, Hopkins C, Sargent J (1990) Trophic relationships in the pelagic, Arctic food web. In: Barnes M, Gibson RN (eds) Trophic relationships in the marine environment: proceedings of the 24th European marine biology symposium. University Press, Aberdeen, pp 315–333Google Scholar
- Falk-Petersen S, Pavlov V, Timofeev S, Sargent JR (2007) Climate variability and possible effects on arctic food chains: the role of Calanus. In: Ørbæk JB, Kallenborn R, Tombre I, Hegseth EN, Falk-Petersen S, Hoel A (eds) Arctic alpine ecosystems and people in a changing environment. Springer, Berlin, pp 147–166CrossRefGoogle Scholar
- Greenacre M, Primicerio R (2013) Multivariate analysis of ecological data. Fundación BBVA, BilbaoGoogle Scholar
- Hagen W (2000) Lipids. In: Harris RP, Wiebe PH, Lenz J, Skjodal HR, Huntley M (eds) ICES zooplankton methodology manual. Academic Press, London, pp 113–119Google Scholar
- Hammer Ø, Harper DAT, Ryan PD (2001) PAST: paleontological statistics software package for education and data analysis. Palaeontol Electron 4(1):9. http://palaeo-electronica.org/2001_1/past/issue1_01.htmtext. Accessed 04 April 2014
- Legeżyńska J, Kędra M, Walkusz W (2014) Identifying trophic relationships within the high Arctic benthic community: how much can fatty acids tell? Mar Biol 161:821–836Google Scholar
- Mauchline J (1980) The Biology of Euphausiids. In: Blaxter JHS, Russel FS, Yonge M (eds) Advances in marine biology. Academic Press, USA, pp 384–419Google Scholar
- Mauchline J, Watling L, Thistle AB (1989) Functional morphology and feeding of euphausiids. In: Felgenhauer BE, Watling L, Thistle AB (eds) Functional morphology of feeding and grooming in Crustacea. A. A. Balkema, Rotterdam, pp 173–184Google Scholar
- Weslawski J, Pedersen G, Falk-Petersen S, Porazinski K (2000) Entrapment of macroplankton in an Arctic fjord basin, Kongsfjorden, Svalbard. Oceanologia 42:57–69Google Scholar
- Wiebe PH (1976) A multiple opening/closing net and environment sensing system for sampling zooplankton. J Mar Res 34:313–326Google Scholar