Respiratory and swimming performance data of Polar cod (Boreogadus saida) under progressive hypoxia and warming

• Main Authors: Kempf, Sarah, Neven, Carolin Julie, Mark, Felix Christopher
• Format: Dataset
• Language: English
• Published: PANGAEA 2023
• Subjects: Binary Object; Binary Object (File Size); Binary Object (MD5 Hash); Field-collected organisms; File content; HE519; HE519_12-1; Heincke; hypoxia; Laboratory experiment; metabolic scope; ocean warming; Pcrit; Polar cod; swimming performance; YFT; Young fish trawl; Arctic; Billefjorden; Boreogadus saida; polar cod
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.962684; https://doi.org/10.1594/PANGAEA.962684

The present study investigated the response of an Arctic keystone species, Polar cod, Boreogadus saida, to hypoxia and warming. We measured the respiratory capacity (standard, routine and maximum metabolic rates, SMR, RMR, MMR, aerobic scope, critical oxygen saturation (Pcrit)) and swimming performance of Polar cod under progressive hypoxia at 2.4 °C and after warm acclimation to close to the species' thermal limit (10.0 °C) via intermittent-flow and swim tunnel respirometry. Polar cod for the experiments in this study were caught in October 2018 during RV HEINCKE expedition HE519 in Billefjorden (78°34'59.99 N 16°27'59.99 E). In total 46 fish were selected for this experiment and divided into two groups. The first group (n = 30, group C) measured 19.7 ± 1.3 cm and 39.6 ± 9.5 g and was kept at habitat temperatures. The second group (n=16, group WA) with an average size of 19.8 ±1.9 cm and weight of 41.3 ± 10.1 g, was progressively acclimated to 10.0 °C (warming rate: 1.5 °C month-1) and then kept at this temperature for several months. For both temperatures, SMR and RMR were measured using seven fully automated respiration chambers (Loligo Systems ApS, Denmark), submerged in two connected thermoregulated tanks (170 L). Oxygen consumption was measured in 12 different PO2 conditions, 100, 75, 65, 55, 45, 35, 30, 25, 20, 15, 10 and 5% air saturation (n = 7 per conditions). Each oxygen saturation was maintained for two days and two nights, containing approximately 80-100 measurement phases during which fish were left undisturbed to ensure proper determination of the SMR as they habituated to the experimental conditions. Only the metabolic rate data from the second night were used for SMR calculation. The respirometers' measurement cycles were 5 min flush, and 30.5 min measurement in the cold group (C) and 2.5 min flush, and 17.5 min measurement in the WA group. The metabolic rate and swimming performance of B. saida under hypoxia were recorded following a critical swimming speed (Ucrit) protocol (Brett (1964), ...