Demersal fishes from the antarctic shelf and deep sea: A diet study based on fatty acid patterns and gut content analyses

• Published in: Deep Sea Research Part II: Topical Studies in Oceanography
• Main Authors: Wuerzberg, L., Peters, J., Florentino De Souza Silva, A.P., Brandt, A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2011
• Subjects: calanoides-acutus; calanus-propinquus; eastern north pacific; feeding-habits; lipid compositions; notothenioid fishes; ross sea; south shetland islands; terra-nova bay; trematomus-bernacchii; Antarctic; Pacific; Ross Sea; South Shetland Islands; Southern Ocean; Terra Nova Bay; The Antarctic; Antarc*
• Online Access: https://research.wur.nl/en/publications/demersal-fishes-from-the-antarctic-shelf-and-deep-sea-a-diet-stud; https://doi.org/10.1016/j.dsr2.2011.05.012

The gut contents and fatty acid composition of 49 fish belonging to five Antarctic demersal families (Nototheniidae, Macrouridae, Channichtyidae, Bathydraconidae and Artedidraconidae) sampled at two stations at the Southern Ocean shelf and deep sea (600 and 2150 m) were analysed in order to identify their main food resource by linking trophic biomarkers with the dietary items found in the fish guts. Main food items of most fish analysed were amphipod crustaceans (e.g. in 63% of Trematomus bernachii guts) and polychaetes (e.g. in 80% of Bathydraco sp. guts), but other food items including fish, other crustaceans and gastropods were also ingested. The most prominent fatty acids found were 20:5(n-3), 16:0, 22:6(n-3) and 18:1(n-9). The results of gut content and fatty acid analyses indicate that all fish except the Channichthyidae share similar food resources irrespective of their depth distribution, i.e. benthic amphipods and polychaetes. A difference of the dietary spectrum can be observed with ontogenetic phases rather than between species, as high values of typical calanoid copepod marker fatty acids as 22:1(n-11) indicate that younger (smaller) specimens include more zooplankton in their diet.