Contribution of sea ice organic matter in the diet of Antarctic fishes: a diatom-specific highly branched isoprenoid approach

• Published in: Polar Biology
• Main Authors: Goutte, Aurélie, Cherel, Yves, Ozouf-Costaz, Catherine, Robineau, Camille, Lanshere, J., Massé, Guillaume
• Other Authors: Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Systématique, adaptation, évolution (SAE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Takuvik Joint International Laboratory ULAVAL-CNRS, Centre National de la Recherche Scientifique (CNRS)-Université Laval Québec (ULaval)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2014
• Subjects: Benthic; Pelagic; Sea ice; Southern Ocean; Ice proxy; Habitat; [SDE]Environmental Sciences; Antarctic; The Antarctic; Antarc*; ice algae; Polar Biology
• Online Access: https://hal.archives-ouvertes.fr/hal-01011139; https://doi.org/10.1007/s00300-014-1489-7

International audience New sets of diatom-specific biomarkers, highly branched isoprenoids (HBIs), have been recently proposed to trace carbon flow from ice algae and pelagic phytoplankton to higher trophic level organisms. In the Antarctic, diene, a HBI of sea ice origin was more abundant in ice-associated species, while triene, a HBI of phytoplanktonic origin, was more abundant in pelagic species. However, this HBI approach has never been applied on Antarctic benthic species. Here, we analyzed diene and triene in the liver and the muscle of eight Antarctic coastal fish species (108 specimens). HBI lipids were detected in all specimens, confirming the contribution of sea ice and pelagic organic matter in coastal benthic fish species. Moreover, HBI markers were much more concentrated in the liver than in white muscle, and the relative concentrations of diene and triene strongly varied among species, as a probable result of species differences in feeding habits and trophic ecology. Seasonal variations in HBI concentrations were detected during the whole year in white muscle, but not in the liver. These findings are consistent with the well-known spring bloom in November-December, just before the annual ice break up, and the second proliferation of ice algae during the land-fast ice formation, in April-May. Therefore, investigation of HBI lipids in white muscle will likely shed new light on seasonal changes in the contribution of ice algal-derived organic matter in higher trophic level organisms.