Feeding ecology and ontogenetic dietary shift of yellowstripe goatfish Mulloidichthys flavolineatus (Mullidae) at Reunion Island, SW Indian Ocean

• Published in: Marine Ecology Progress Series
• Main Authors: Kolasinski, Joanna, Patrick, Frouin, Sallon, Amelie, Rogers, Karyne, Bruggemann, J. Henrich, Potier, Michel
• Other Authors: Laboratoire d'Ecologie Marine (ECOMAR), Université de La Réunion (UR), Ecosystèmes Marins Exploités (UMR EME), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Montpellier (UM)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2009
• Subjects: coral-reef; delta-c-13; delta-n-15; fish communities; food-web; Mixing model; new-caledonia; northern gulf; Ontogenetic diet shift; sciaenops-ocellatus larvae; Southwestern Indian Ocean; Stable isotopes; stable-isotope ratios; Stomach contents; trophic position; Yellowstripe goatfish; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Indian; Sciaenops ocellatus; Copepods
• Online Access: https://hal.science/hal-00858448; https://doi.org/10.3354/meps08081

We analyzed stomach contents and muscle isotopic composition (delta C-13, delta N-15) of yellowstripe goatfish Mulloidichthys flavolineatus from a coral reef to investigate size-related dietary changes and resource or habitat partitioning. Juveniles (\textless 12 cm total length [TL]), young adults (12 \textless= TL \textless 17 cm) and adults (\textgreater= 17 cm TL) showed a high diet overlap, especially between juveniles and young adults. According to stomach contents analysis, M. flavolineatus widens its prey spectrum with increasing size from a common prey pool that includes polychaetes, tanaids and harpacticoid copepods. We observed a significant increase in delta C-13 values (from -17.1 +/- 0.5 parts per thousand for juveniles to -10.7 +/- 0.8 parts per thousand for adults), which were correlated to fish size. Adults (delta N-15 mean of 11.1 +/- 1.8 parts per thousand) were one trophic level above juveniles and young adults (7.7 +/- 0.5 and 7.4 +/- 0.5 parts per thousand, respectively). These patterns of isotopic changes confirmed ontogenetic dietary shifts. However, trophodynamics can be influenced by physiological factors such as growth and sexual maturity. M flavolineatus shift from a pelagic to a macrobenthic diet, which is equilibrated at the adult stage. Results from combined stomach contents (prey volume) and stable isotope analyses suggested a dominant contribution of polychaetes (macrofauna), possibly through selective feeding. Conversely, on the basis of prey volume and stable isotope data, meiofauna did not feature significantly in the diet despite their high abundance in stomachs. Two adult groups were distinguished based on their delta N-15 values (11.9 +/- 0.8 and 7.8 +/- 0.6 parts per thousand), indicating possible stage-specific partitioning in habitat use inside the reef.