Oxidative stress, metabolic activity and mercury concentrations in Antarctic krill Euphausia superba and myctophid fish of the Southern Ocean

• Published in: Marine Pollution Bulletin
• Main Authors: Seco, José, Freitas, Rosa, Xavier, José C., Bustamante, Paco, Coelho, João P., Coppola, Francesca, Saunders, Ryan A., Almeida, Ângela, Fielding, Sophie, Pardal, Miguel A., Stowasser, Gabriele, Pompeo, Giulia, Tarling, Geraint A., Brierley, Andrew S., Pereira, Eduarda
• Other Authors: University of St Andrews. Marine Alliance for Science & Technology Scotland, University of St Andrews. Scottish Oceans Institute, University of St Andrews. Pelagic Ecology Research Group, University of St Andrews. Centre for Research into Ecological & Environmental Modelling, University of St Andrews. School of Biology
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2022
• Subjects: Toxicity; Biochemical performance; Antioxidant capacity; Baseline; QH301 Biology; T-NDAS; AC; QH301; Antarc*; Antarctic; Antarctic Krill; Antarctica; Euphausia superba; Southern Ocean
• Online Access: https://hdl.handle.net/10023/24862; https://doi.org/10.1016/j.marpolbul.2021.112178

Authors acknowledge the financial support of the Portuguese Foundation for the Science and Technology (FCT) through PhD grants to José Seco (SRFH/PD/BD/113487), Francesca Coppola (SFRH/BD/118582/2016) and Ângela Almeida (SFRH/BD/110218/2015), and the Portuguese Polar Program PROPOLAR. This study also benefited from the strategic program of MARE (Marine and Environmental Sciences Centre) financed by FCT (UIDB/04292/2020). João Pedro Coelho was funded by the Integrated Program of SR&TD ‘Smart Valorization of Endogenous Marine Biological Resources Under a Changing Climate’ (Centro-01-0145-FEDER-000018), co-funded by Centro 2020 program, Portugal 2020 and the European Regional Development Fund. Thanks are due for the financial support to CESAM (UIDB/50017/2020+UIDP/50017/2020) and REQUIMTE (UIDB/50006/2020). The Institut Universitaire de France (IUF) is acknowledged for its support to P. Bustamante as a Senior Member. RAS, SF, GS and GT were supported by the British Antarctic Surveys Ecosystem Programme, which is part of NERC and UKRI. Indicators of oxidative stress and metabolic capacity are key factors in understanding the fitness of wild populations. In the present study, these factors were evaluated in the pelagic Southern Ocean taxa Antarctic krill (Euphausia superba) and myctophid fish (Electrona antarctica, Gymnoscopelus braueri and G. nicholsi) to establish a baseline record for future studies. Mercury (Hg) concentrations were also analysed to evaluate its potential impacts on species biochemical performance. E. superba had higher metabolic activity than most of the myctophid species, which may explain the comparatively lower energy reserves found in the former. The activity of antioxidant enzymes showed, generally, a lower level in E. superba than in the myctophid species. The lack of any relationship between Hg concentrations and organisms' antioxidant and biotransformation defence mechanisms indicate that levels of Hg accumulated in the studied species were not high enough to affect their ...