Energetic plasticity underlies a variable response to ocean acidification in the pteropod, Limacina helicina antarctica.

• Published in: PLoS ONE
• Main Authors: Brad A Seibel, Amy E Maas, Heidi M Dierssen
• Format: Article in Journal/Newspaper
• Language: English
• Published: Public Library of Science (PLoS) 2012
• Subjects: Medicine; R; Science; Q; Antarc*; Antarctica; Limacina helicina; Ocean acidification
• Online Access: https://doi.org/10.1371/journal.pone.0030464; https://doaj.org/article/5bda6670566b4de997581f56384bd2cf

Ocean acidification, caused by elevated seawater carbon dioxide levels, may have a deleterious impact on energetic processes in animals. Here we show that high PCO(2) can suppress metabolism, measured as oxygen consumption, in the pteropod, L. helicina forma antarctica, by ∼20%. The rates measured at 180-380 µatm (MO(2) = 1.25 M(-0.25), p = 0.007) were significantly higher (ANCOVA, p = 0.004) than those measured at elevated target CO(2) levels in 2007 (789-1000 µatm, = 0.78 M(-0.32), p = 0.0008; Fig. 1). However, we further demonstrate metabolic plasticity in response to regional phytoplankton concentration and that the response to CO(2) is dependent on the baseline level of metabolism. We hypothesize that reduced regional Chl a levels in 2008 suppressed metabolism and masked the effect of ocean acidification. This effect of food limitation was not, we postulate, merely a result of gut clearance and specific dynamic action, but rather represents a sustained metabolic response to regional conditions. Thus, pteropod populations may be compromised by climate change, both directly via CO(2)-induced metabolic suppression, and indirectly via quantitative and qualitative changes to the phytoplankton community. Without the context provided by long-term observations (four seasons) and a multi-faceted laboratory analysis of the parameters affecting energetics, the complex response of polar pteropods to ocean acidification may be masked or misinterpreted.