Trophic relationships in a deep Mediterranean cold-water coral bank (Santa Maria di Leuca, Ionian Sea)

摘要: Cold-water corals (CWC) are frequently reported from deep sites with locally accelerated currents that enhance seabed food particle supply. Moreover, zooplankton likely account for ecologically important prey items, but their contribution to CWC diet remains unquantified. We investigated the benthic web structure of recently discovered Santa Maria di Leuca (SML) province (300 1100 m depth) located in oligotrophic northern Ionian Sea. analyzed stable isotopes (δ13C and δ15N) main consumers (including ubiquitous species) exhibiting different feeding strategies, zooplankton, suspended particulate organic matter (POM) sedimented (SOM). Zooplankton POM were collected 3 above coral colonies order assess relative contributions diet. The δ15N scleractinians Desmophyllum dianthus, Madrepora oculata Lophelia pertusa (8 9‰) gorgonian Paramuricea cf. macrospina (9 10‰) consistent a mainly composed (6 7‰). antipatharian Leiopathes glaberrima was more 15N-depleted (7 8‰) than other cnidarians, suggesting lower its Our δ13C data clearly indicate SML is exclusively fuelled by carbon phytoplanktonic origin. Nevertheless, at water–sediment interface 13C-enriched bottom (i.e. living epifauna). This pattern suggests assimilated via 2 trophic pathways: relatively fresh production 13C-depleted decayed consumers. When values corrected influence lipids (which significantly tissue components), our conclusions remained unchanged, except case L. which could assimilate mixture resuspended matter.