Seawater carbonate chemistry and ion-transporting capacity and aerobic respiration of larval white seabass (Atractoscion nobilis)

• Main Authors: Kwan, Garfield Tsz, Shen, Sara G, Drawbridge, Mark, Tresguerres, Martin
• Format: Dataset
• Language: English
• Published: PANGAEA 2021
• Subjects: Alkalinity; total; Animalia; Aragonite saturation state; Atractoscion nobilis; Bicarbonate ion; Bottles or small containers/Aquaria (<20 L); Calcite saturation state; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Chordata; Coast and continental shelf; Experiment; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Growth rate; standard error; Ionocyte density; Ionocyte number; Ionocyte size; Laboratory experiment; Length; Nekton; North Atlantic; OA-ICC; Ocean Acidification International Coordination Centre; Other studied parameter or process; Oxygen consumption; Oxygen consumption per individual; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Pelagos; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.933100; https://doi.org/10.1594/PANGAEA.933100

Ocean acidification (OA) has been proposed to increase the energetic demand for acid-base regulation at the expense of larval fish growth. Here, white seabass (Atractoscion nobilis) eggs and larvae were reared at control (542 +/- 28 μatm) and elevated pCO2 (1,831 +/- 105 μatm) until five days post-fertilization (dpf). Skin ionocytes were identified by immunodetection of the Na+/K+-ATPase (NKA) enzyme. Larvae exposed to elevated pCO2 possessed significantly higher skin ionocyte number and density compared to control larvae. However, when ionocyte size was accounted for, the relative ionocyte area (a proxy for total ionoregulatory capacity) was unchanged. Similarly, there were no differences in relative NKA abundance, resting O2 consumption rate, and total length between control and treatment larvae at 5 dpf, nor in the rate at which relative ionocyte area and total length changed between 2–5 dpf. Altogether, our results suggest that OA conditions projected for the next century do not significantly affect the ionoregulatory capacity or energy consumption of larval white seabass. Finally, a retroactive analysis of the water in the recirculating aquarium system that housed the broodstock revealed the parents had been exposed to average pCO2 of 1,200 μatm for at least 3.5 years prior to this experiment. Future studies should investigate whether larval white seabass are naturally resilient to OA, or if this resilience is the result of parental chronic acclimation to OA, and/or from natural selection during spawning and fertilization in elevated pCO2.