Effect of increased CO in seawater on survival rate of different developmental stages of the harpacticoid copepod .

The rapid increase in carbon dioxide levels in seawater is causing ocean acidification and is expected to have significant effects on marine life. To explore the ability of the harpacticoid copepod to adapt to an increased concentration of dissolved carbon dioxide (CO) in seawater, we compared the survival rates of adult and nauplius stages at 400, 1000, and 1550 ppm CO over a 14-day period. The survival rate of dramatically decreased over time with increase in CO concentration. At 1550 ppm, the survival rate showed a decrease of more than 20% at the end of the experimental period over that at 400 ppm. Furthermore, the survival rate decreased by a greater amount at all concentrations in nauplii than in adults, with a greater effect in wild-collected specimens than in culture-derived individuals. The results suggest that future ocean acidification may negatively influence the sustainability of and thus may eventually influence benthic ecosystems.