Response of the Arctic Pteropod Limacina helicina to Projected Future Environmental Conditions

Thecosome pteropods (pelagic mollusks) can play a key role in the food web of various marine ecosystems. They are a food source for zooplankton or higher predators such as fishes, whales and birds that is particularly important in high latitude areas. Since they harbor a highly soluble aragonitic shell, they could be very sensitive to ocean acidification driven by the increase of anthropogenic CO2 emissions. The effect of changes in the seawater chemistry was investigated on Limacina helicina, a key species of Arctic pelagic ecosystems. Individuals were kept in the laboratory under controlled pCO2 levels of 280, 380, 550, 760 and 1020 µatm and at control (0°C) and elevated (4°C) temperatures. The respiration rate was unaffected by pCO2 at control temperature, but significantly increased as a function of the pCO2 level at elevated temperature. pCO2 had no effect on the gut clearance rate at either temperature. Precipitation of CaCO3, measured as the incorporation of 45Ca, significantly declined as a function of pCO2 at both temperatures. The decrease in calcium carbonate precipitation was highly correlated to the aragonite saturation state. Even though this study demonstrates that pteropods are able to precipitate calcium carbonate at low aragonite saturation state, the results support the current concern for the future of Arctic pteropods, as the production of their shell appears to be very sensitive to decreased pH. A decline of pteropod populations would likely cause dramatic changes to various pelagic ecosystems.

[1]  R. Berner,et al.  Pelagic sedimentation of aragonite: its geochemical significance. , 1981, Science.

[2]  A. Mucci.  The solubility of calcite and aragonite in seawater at various salinities , 1983 .

[3]  T. Ikeda,et al.  Metabolic rates of epipelagic marine zooplankton as a function of body mass and temperature , 1985 .

[4]  K. Christoffersen,et al.  Gut evacuation rates and ingestion rates of Eudiaptomus graciloides measured by means of the gut fluorescence method , 1986 .

[5]  R. W. Gilmer,et al.  Morphology and field behavior of pteropod molluscs: feeding methods in the families Cavoliniidae, Limacinidae and Peraclididae (Gastropoda: Thecosomata) , 1986 .

[6]  H. Dam,et al.  The effect of temperature on the gut clearance rate constant of planktonic copepods , 1988 .

[7]  R. W. Gilmer,et al.  Pelagic Snails: The Biology of Holoplanktonic Gastropod Mollusks , 1989 .

[8]  V. Fabry.  Shell growth rates of pteropod and heteropod molluscs and aragonite production in the open ocean: Implications for the marine carbonate system , 1990 .

[9]  G. Harbison,et al.  Diet of Limacina helicina (Gastropoda: Thecosomata) in Arctic waters in midsummer , 1991 .

[10]  J. Gattuso,et al.  Validation of the alkalinity anomaly technique for investigating calcification of photosynthesis in coral reef communities , 1991 .

[11]  Robert W. Buddemeier,et al.  Effect of calcium carbonate saturation of seawater on coral calcification , 1998 .

[12]  J. Węsławski,et al.  Greenland whales and walruses in the Svalbard food web before and after exploitation , 2000 .

[13]  Ulf Riebesell,et al.  Reduced calcification of marine plankton in response to increased atmospheric CO2 , 2000, Nature.

[14]  R. Collier,et al.  The vertical flux of biogenic and lithogenic material in the Ross Sea : moored sediment trap observations 1996-1998 , 2000 .

[15]  R. T. Cooney,et al.  Ecological processes influencing mortality of juvenile pink salmon ( Oncorhynchus gorbuscha ) in Prince William Sound, Alaska , 2001 .

[16]  J. B. Ørbæk,et al.  The physical environment of Kongsfjorden–Krossfjorden, an Arctic fjord system in Svalbard , 2002 .

[17]  Richard A. Krishfield,et al.  Factors controlling the flux of organic carbon to the bathypelagic zone of the ocean , 2002 .

[18]  J. Jaubert,et al.  Interacting effects of CO2 partial pressure and temperature on photosynthesis and calcification in a scleractinian coral , 2003 .

[19]  K. Caldeira,et al.  Oceanography: Anthropogenic carbon and ocean pH , 2003, Nature.

[20]  Nicolas Gruber,et al.  The Oceanic Sink for Anthropogenic CO2 , 2004, Science.

[21]  Richard A. Feely,et al.  Impact of Anthropogenic CO2 on the CaCO3 System in the Oceans , 2004, Science.

[22]  F. Cottier,et al.  Water mass modification in an Arctic fjord through cross-shelf exchange: The seasonal hydrography of Kongsfjorden, Svalbard , 2005 .

[23]  E. Maier‐Reimer,et al.  Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms , 2005, Nature.

[24]  Chris Langdon,et al.  Effect of elevated pCO2 on photosynthesis and calcification of corals and interactions with seasonal change in temperature/irradiance and nutrient enrichment , 2005 .

[25]  H. Hop,et al.  The Arctic sea butterfly Limacina helicina: lipids and life strategy , 2005 .

[26]  R..  Diet of Limacina helicina ( Gastropoda : Thecosomata ) in Arctic waters in midsummer , 2006 .

[27]  C. Heip,et al.  Impact of elevated CO 2 on shellfish calcification , 2007 .

[28]  Olivier Aumont,et al.  The fate of pelagic CaCO 3 production in a high CO 2 ocean: a model study , 2007 .

[29]  Andrew G. Dickson,et al.  Guide to best practices for ocean CO2 measurements , 2007 .

[30]  C. Heip,et al.  Impact of elevated CO2 on shellfish calcification , 2007 .

[31]  Julia C. Hargreaves,et al.  Assessing the potential long-term increase of oceanic fossil fuel CO 2 uptake due to CO 2 -calcification feedback , 2007 .

[32]  B. Seibel,et al.  Metabolic temperature compensation and coevolution of locomotory performance in pteropod molluscs. , 2007, Integrative and comparative biology.

[33]  R. Matear,et al.  Climate change feedbacks on future oceanic acidification , 2007 .

[34]  F. Joos,et al.  Modeling the marine aragonite cycle: changes under rising carbon dioxide and its role in shallow water CaCO 3 dissolution , 2008 .

[35]  K. Hobson,et al.  Seasonal changes in diets of seabirds in the North Water Polynya: a multiple-indicator approach , 2008 .

[36]  Richard A. Feely,et al.  Impacts of ocean acidification on marine fauna and ecosystem processes , 2008 .

[37]  G. Hosie,et al.  Pteropods in Southern Ocean ecosystems , 2008 .

[38]  K. Bernard,et al.  The sub-Antarctic euthecosome pteropod, Limacina retroversa: Distribution patterns and trophic role , 2009 .

[39]  S. Comeau,et al.  Impact of ocean acidification on a key Arctic pelagic mollusc ( Limacina helicina ) , 2009 .

[40]  W. Howard,et al.  Reduced calcification in modern Southern Ocean planktonic foraminifera , 2009 .

[41]  J. Ries,et al.  Marine calcifiers exhibit mixed responses to CO2-induced ocean acidification , 2009 .

[42]  F. Joos,et al.  Imminent ocean acidification in the Arctic projected with the NCAR global coupled carbon cycle-climate model , 2009 .

[43]  Koji Shimada,et al.  Aragonite Undersaturation in the Arctic Ocean: Effects of Ocean Acidification and Sea Ice Melt , 2009, Science.

[44]  J. Hall‐Spencer,et al.  Effects of ocean acidification and high temperatures on the bryozoan Myriapora truncata at natural CO2 vents , 2010 .

[45]  J. Hall‐Spencer,et al.  Effects of ocean acidification and high temperatures on the bryozoan Myriapora truncata at natural CO 2 vents , 2010 .

[46]  B. Seibel,et al.  Poles Apart: The “Bipolar” Pteropod Species Limacina helicina Is Genetically Distinct Between the Arctic and Antarctic Oceans , 2010, PloS one.