Fatty acid composition of the amphipod Dikerogammarus villosus: feeding strategies and trophic links.
Fatty acid (FA) compositions were determined for the invader amphipod Dikerogammarus villosus collected from July to September 2002, in an overheated, high-conductivity dammed reservoir in north-eastern France. Predominant fatty acids were the polyunsaturated fatty acids (PUFA): eicosapentaenoic acid (EPA), linoleic acid (LA), arachidonic acid (ARA), linolenic acid (LNA) together with the monounsaturated fatty acid 18:1omega9 and the saturated fatty acid 16:0. FA markers indicated that available food was constituted of incompletely degraded phytodetritus and terrestrial inputs, as well as animal remains. PUFA contents depended on the diet and the capacity of animals to desaturate and elongate LNA and LA in long chain PUFA as EPA and ARA respectively. Based on their FA compositions, we showed that gammarids represent naturally-occurring freshwater sources of essential PUFA, and could play a fundamental role in pelagic-benthic coupling and energy recycling in the ecosystem. The complexity of the feeding strategies of D. villosus--detritivorous, omnivorous, carnivorous--makes this species efficient at exploiting different components of the available food and may be a key factor in its high invasive success.
Maazouzi
Chafik
C
Université Paul Verlaine - Metz, Laboratoire Interactions Ecotoxicologie, Biodiversité, Ecosystèmes (L.I.E.B.E) - CNRS UMR 7146, Campus Bridoux, Avenue Général Delestraint, 57070 Metz. France. maazouzi@nuiv-metz.fr
Masson
Gérard
G
Izquierdo
Maria Soledad
MS
Pihan
Jean-Claude
JC
D033304:Amphipoda / Q000737:chemistry*; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D005227:Fatty Acids / Q000032:analysis*; D005231:Fatty Acids, Unsaturated / Q000032:analysis; D005247:Feeding Behavior / Q000502:physiology*; D005260:Female; D005618:Fresh Water; D005843:Geography; D008297:Male
D015415:Biomarkers; D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated