Tolerance of Hyas araneus zoea I larvae to elevated seawater PCO2 despite elevated metabolic costs

• Published in: Marine Biology
• Main Authors: Schiffer, Melanie, Harms, Lars, Pörtner, Hans-O., Lucassen, Magnus, Mark, Felix C., Storch, Daniela
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer 2013
• Subjects: Svalbard
• Online Access: https://oceanrep.geomar.de/id/eprint/19184/; https://oceanrep.geomar.de/id/eprint/19184/1/art_10.1007_s00227-012-2036-0.pdf; https://doi.org/10.1007/s00227-012-2036-0

Early life stages of marine crustaceans respond sensitively to elevated seawater P CO 2 . However, the underlying physiological mechanisms have not been studied well. We therefore investigated the effects of elevated seawater P CO 2 on oxygen consumption, dry weight, elemental composition, median developmental time (MDT) and mortality in zoea I larvae of the spider crab Hyas araneus (Svalbard 79°N/11°E; collection, May 2009; hatch, December 2009). At the time of moulting, oxygen consumption rate had reached a steady state level under control conditions. In contrast, elevated seawater P CO 2 caused the metabolic rate to rise continuously leading to a maximum 1.5-fold increase beyond control level a few days before moulting into the second stage (zoea II), followed by a pronounced decrease. Dry weight of larvae reared under high CO 2 conditions was lower than in control larvae at the beginning of the moult cycle, yet this difference had disappeared at the time of moulting. MDT of zoea I varied between 45 ± 1 days under control conditions and 42 ± 2 days under the highest seawater CO 2 concentration. The present study indicates that larval development under elevated seawater P CO 2 levels results in higher metabolic costs during premoulting events in zoea I. However, H. araneus zoea I larvae seem to be able to compensate for higher metabolic costs as larval MDT and survival was not affected by elevated P CO 2 level