Long-term effects of ocean acidification upon energetics and oxygen transport in the European sea bass (Dicentrarchus labrax, Linnaeus)

• Published in: Marine Biology
• Main Authors: Crespel, Amelie, Anttila, Katja, Lelievre, Pernelle, Quazuguel, Patrick, Le Bayon, Nicolas, Zambonino-Infante, Jose-Luis, Chabot, Denis, Claireaux, Guy
• Other Authors: Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), University of Turku, Fisheries and Oceans Canada (DFO)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: ACL; temperature; co2; acid; acclimation; aerobic scope; carbon-dioxide; gas-exchange; marine fish; metabolic-rate; performance; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Ocean acidification
• Online Access: https://hal.science/hal-02868565; https://hal.science/hal-02868565/document; https://hal.science/hal-02868565/file/66604.pdf; https://doi.org/10.1007/s00227-019-3562-9

WOS:000482385600002 The accumulation of CO2 in the atmosphere and resulting ocean acidification represent a threat to marine ecosystems. While acid-base regulatory capacity is well developed in marine fish, allowing compensation of extra-cellular pH during short-term hypercapnia, the possible energetic costs of such regulation during long-term exposure remain to be established. In this study, juvenile European sea bass (Dicentrarchus labrax) were exposed from 2 days post-hatching to three different ocean acidification scenarios: control (present condition, PCO2-69pt 520 mu atm, pH 7.9), moderate acidification (PCO2\document\ treatments did not affect fish standard metabolic rate (SMR). However, the most severe acidification condition was associated with a significantly elevated maximum metabolic rate (MMR).This was supported by heavier gill system and higher blood haemoglobin concentration. A reduction of maximum cardiac frequency (f(Hmax)) during incremental warming of anaesthetized fish was also observed in both acidification scenarios. On the other hand, the critical oxygen level (O-2crit), the minimum oxygen level required to sustain SMR, did not differ among groups. The increased MMR, associated with maintained SMR, suggests that acid-base compensatory processes, although not increasing maintenance costs, may affect components of bass homeostasis, resulting in new internal physico-chemical conditions. The possibility that these alterations influence metabolic pathways and physiological functions involved in fish aptitude to maximally transport oxygen is discussed.