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

• Published in: PloS one 2012-04, Vol.7 (4), p.e30464
• Main Authors: Seibel, Brad A, Maas, Amy E, Dierssen, Heidi M
• Format: Article
• Language: English
• Subjects: Acidification; Animals; Antarctic Regions; Biodiversity; Biology; Body Weight; Carbon dioxide; Carbon Dioxide - chemistry; Carbon dioxide in seawater; Carbonates - chemistry; Chemical analysis; Chemistry; Chlorophyll; Climate change; Clione limacina; Earth Sciences; Ecosystems; Energy Metabolism; Fatty acids; Food; Gastropoda - metabolism; Global temperature changes; Gymnosomata; Hydrogen-Ion Concentration; Limacina; Limacina helicina; Metabolic response; Metabolism; Ocean acidification; Oceans; Oceans and Seas; Organisms; Oxygen; Oxygen Consumption; Physiological aspects; Physiology; Phytoplankton; Plastic properties; Plasticity; Protein synthesis; Remote sensing; Seawater; Seawater - chemistry; Water analysis
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0030464

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.