Temporal and inter-specific variations in forage fish feeding conditions in the NW Mediterranean : lipid content and fatty acid compositional changes

摘要: We describe the total lipid content, class composition and fatty acid profiles of adult forage fishes (anchovy, sardine sprat) sampled in NW Mediterranean Sea 2010 2011. Interand intra-species differences were mostly related to sampling period with limited effect gender or length. As an assemblage, content relative levels triacylglycerols acids 16:1n7, 20:5n3 14:0 fish highest summer autumn, indicating better feeding conditions a more pronounced diatom-supported food web. In contrast, was lowest at end winter spring, coincided high 22:6n3, herbivorous diet based on dinoflagellates. Resource partitioning niche separation, as inferred from profiles, apparent between species. Sardine showed diverse, temporally separated strategy than anchovy, dietary overlap higher having markers copepods, 22:1n11 20:1n9. Sprat collected occupied separate area both anchovy carnivory biomarker 18:1n9. Our results show that dynamics can be used gain quantitative insights into sub-system level changes species interactions, including prey predator productivity.