Long-term effects of elevated CO2 and temperature on the Arctic calanoid copepods Calanus glacialis and C. hyperboreus

• Published in: Marine Pollution Bulletin
• Main Authors: Hildebrandt, Nicole, Niehoff, Barbara, Sartoris, Franz Josef
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2014
• Subjects: Arctic; Calanus glacialis; Ocean acidification; Copepods
• Online Access: https://oceanrep.geomar.de/id/eprint/25310/; https://oceanrep.geomar.de/id/eprint/25310/1/Hildebrandt%20et.al.pdf; https://doi.org/10.1016/j.marpolbul.2014.01.050

Highlights • First long-term experiments on effects of high pCO2 and temperature on Calanus spp. • CO2 concentration of 3000 μatm had no effect on the copepods performance. • Temperature of 10 °C induced sublethal stress in diapausing C. hyperboreus females. • Synergistic effects of temperature and CO2 on body carbon were found at 5 °C. Abstract The sensitivity of copepods to ocean acidification (OA) and warming may increase with time, however, studies >10 days and on synergistic effects are rare. We therefore incubated late copepodites and females of two dominant Arctic species, Calanus glacialis and Calanushyperboreus, at 0 °C at 390 and 3000 μatm pCO2 for several months in fall/winter 2010. Respiration rates, body mass and mortality in both species and life stages did not change with pCO2. To detect synergistic effects, in 2011 C. hyperboreus females were kept at different pCO2 and temperatures (0, 5, 10 °C). Incubation at 10 °C induced sublethal stress, which might have overruled effects of pCO2. At 5 °C and 3000 μatm, body carbon was significantly lowest indicating a synergistic effect. The copepods, thus, can tolerate pCO2 predicted for a future ocean, but in combination with increasing temperatures they could be sensitive to OA.