Lipid compositions of calanoid copepods and an ostracod from Kongsfjorden and the Marginal Ice Zone north of Svalbard: Dietary Influences

No abstracts are to be cited without prior reference to the author.

The three dominant Calanus species, Calanus finmarchicus, C. glacialis, and C. hyperboreus, were sampled at different locations along the Arctic Marginal Ice Zone (different types and ages of ice) around Svalbard and in Kongsfjorden, an Arctic fjord. High-Arctic Scaphocalanus magnus, a calanoid copepod, and an ostracod, Conchoecia borealis, were sampled only at the MIZ sites. Changes and difference in the lipid biochemistry (deposition of lipid classes and biomarkers) were used to investigate the different species under different physical regimes and potentially different food regimes. Stage V C. hyperboreus, for example, show greater lipid deposition at the MIZ-multipleyear old ice site compared to other sites. Stage V C. hyperboreus sampled at ice sites also have higher amounts of TAG and wax esters than at the fjord site. Site specific differences in the fatty acid composition were evident in the three calanoid species reflecting the variability in the phytoplankton composition. Diatom markers were more abundant at sites experiencing the bloom and flagellate markers were more abundant at sites where the seasonal bloom had passed. The dominant fatty acid biomarkers in the C. borealis wax esters and S. magnus TAG suggest an omnivorous behaviour and, potentially, particulate feeding on material originating from the larger Calanus copepods. The importance of the ice habitat in maintaining high quality particulate material is discussed.