High CO2 reduces the settlement of a spawning coral on three common species of crustose coralline algae

Concern about the impacts of ocean acidification (OA) on ecosystem function has prompted many studies to focus on larval recruitment, demonstrating declines in settlement and early growth at elevated CO2 concentrations. Since larval settlement is often driven by particular cues governed by crustose coralline algae (CCA), it is important to determine whether OA reduces larval recruitment with specific CCA and the generality of any effects. We tested the effect of elevated CO2 on the survival and settlement of larvae from the common spawning coral Acropora selago with 3 ecologically important species of CCA, Porolithon onkodes, Sporolithon sp., and Titanoderma sp. After 3 d in no-choice laboratory assays at 447, 705, and 1214 μatm pCO2, the rates of coral settlement declined as pCO 2 increased with all CCA taxa. The magnitude of the effect was highest with Titanoderma sp., decreasing by 87% from the ambient to highest CO2 treatment. In general, there were high rates of larval mortality, which were greater with the P. onkodes and Sporolithon sp. treatments (~80%) compared to the Titanoderma sp. treatment (65%). There was an increase in larval mortality as pCO2 increased, but this was variable among the CCA species. It appears that OA reduces coral settlement by rapidly altering the chemical cues associated with the CCA thalli and microbial community, and potentially by directly affecting larval viability.

[1]  Corinne Le Quéré,et al.  Climate Change 2013: The Physical Science Basis , 2013 .

[2]  N. Webster,et al.  Ocean acidification reduces induction of coral settlement by crustose coralline algae , 2012, Global change biology.

[3]  P. Mumby,et al.  Interactions among chronic and acute impacts on coral recruits: the importance of size-escape thresholds. , 2012, Ecology.

[4]  O. Hoegh‐Guldberg,et al.  Ocean acidification reduces coral recruitment by disrupting intimate larval-algal settlement interactions. , 2012, Ecology letters.

[5]  O. Hoegh‐Guldberg,et al.  INTERACTIONS BETWEEN OCEAN ACIDIFICATION AND WARMING ON THE MORTALITY AND DISSOLUTION OF CORALLINE ALGAE 1 , 2012, Journal of phycology.

[6]  C. Wild,et al.  Effects of ocean acidification on microbial community composition of, and oxygen fluxes through, biofilms from the Great Barrier Reef. , 2011, Environmental microbiology.

[7]  C. Langdon,et al.  Ocean acidification impacts multiple early life history processes of the Caribbean coral Porites astreoides , 2011 .

[8]  M. Byrne.  IMPAcT oF ocEAN wARMING AND ocEAN AcIDIFIcATIoN oN MARINE INvERTEbRATE lIFE HISToRy STAGES: vulNERAbIlITIES AND PoTENTIAl FoR PERSISTENcE IN A cHANGING ocEAN , 2011 .

[9]  A. Suzuki,et al.  Coral Larvae under Ocean Acidification: Survival, Metabolism, and Metamorphosis , 2011, PloS one.

[10]  A. Dickson.  The carbon dioxide system in seawater : equilibrium chemistry and measurements 1 , 2011 .

[11]  D. Wallace,et al.  MS Excel Program Developed for CO2 System Calculations , 2011 .

[12]  H. Elifantz,et al.  The impact of reduced pH on the microbial community of the coral Acropora eurystoma , 2011, The ISME Journal.

[13]  Ulf Riebesell,et al.  Guide to best practices for ocean acidification research and data reporting , 2011 .

[14]  C. Langdon,et al.  Ocean acidification compromises recruitment success of the threatened Caribbean coral Acropora palmata , 2010, Proceedings of the National Academy of Sciences.

[15]  R. Steneck,et al.  Running the Gauntlet: Inhibitory Effects of Algal Turfs on the Processes of Coral Recruitment , 2010 .

[16]  N. Price.  Habitat selection, facilitation, and biotic settlement cues affect distribution and performance of coral recruits in French Polynesia , 2010, Oecologia.

[17]  J. LaRoche,et al.  Bioassays, batch culture and chemostat experimentation, Approaches and tools to manipulate the carbonate chemistry , 2010 .

[18]  R. Steneck,et al.  Larval settlement preferences and post-settlement survival of the threatened Caribbean corals Acropora palmata and A. cervicornis , 2010, Coral Reefs.

[19]  O. Hoegh‐Guldberg,et al.  The impact of benthic algae on the settlement of a reef-building coral , 2010, Coral Reefs.

[20]  K. Gao,et al.  Combined effects of ocean acidification and solar UV radiation on photosynthesis, growth, pigmentation and calcification of the coralline alga Corallina sessilis (Rhodophyta) , 2009 .

[21]  Laura J. Falkenberg,et al.  Synergistic effects of climate change and local stressors: CO2 and nutrient‐driven change in subtidal rocky habitats , 2009 .

[22]  A. Cohen,et al.  Morphological and compositional changes in the skeletons of new coral recruits reared in acidified seawater: Insights into the biomineralization response to ocean acidification , 2009 .

[23]  K. Shimada,et al.  Effects of acidified seawater on early life stages of scleractinian corals (Genus Acropora) , 2009, Fisheries Science.

[24]  H. Kurihara.  Effects of CO2-driven ocean acidification on the early developmental stages of invertebrates , 2008 .

[25]  O. Hoegh-Guldberg,et al.  Ocean acidification causes bleaching and productivity loss in coral reef builders , 2008, Proceedings of the National Academy of Sciences.

[26]  M. Thorndyke,et al.  Near-future levels of ocean acidificat ion reduce fert ilizat ion success in a sea urchin , 2018 .

[27]  Emma Ransome,et al.  Volcanic carbon dioxide vents show ecosystem effects of ocean acidification , 2008, Nature.

[28]  B. Willis,et al.  Effects of benthic algae on the replenishment of corals and the implications for the resilience of coral reefs , 2008 .

[29]  W. Collins,et al.  Global climate projections , 2007 .

[30]  Glenn De'ath,et al.  RECOGNITION AND SELECTION OF SETTLEMENT SUBSTRATA DETERMINE POST-SETTLEMENT SURVIVAL IN CORALS , 2004 .

[31]  L. Blackall,et al.  Metamorphosis of a Scleractinian Coral in Response to Microbial Biofilms , 2004, Applied and Environmental Microbiology.

[32]  M. Littler,et al.  South Pacific Reef Plants: A Divers' Guide to the Plant Life of South Pacific Coral Reefs , 2003 .

[33]  R. Hill,et al.  Metamorphosis of broadcast spawning corals in response to bacteria isolated from crustose algae , 2001 .

[34]  A. Heyward,et al.  Natural inducers for coral larval metamorphosis , 1999, Coral Reefs.

[35]  Langdon,et al.  Geochemical consequences of increased atmospheric carbon dioxide on coral reefs , 1999, Science.

[36]  W. Woelkerling,et al.  Settlement of abalone larvae (Haliotis laevigata Donovan) in response to non-geniculate coralline red algae (Corallinales, Rhodophyta) , 1999 .

[37]  T. Kawaguchi,et al.  Isolation of an allelopathic substance from the crustose coralline algae, Lithophyllum spp., and its effect on the brown alga, Laminaria religiosa Miyabe (Phaeophyta) , 1998 .

[38]  N. Inestrosa,et al.  Settlement of benthic marine invertebrates , 1993 .

[39]  D. Morse,et al.  Control of larval metamorphosis and recruitment in sympatric agariciid corals , 1988 .

[40]  M. Doty,et al.  Ecological Components Structuring the Seaward Edges of Tropical Pacific Reefs: The Distribution, Communities and Productivity of Porolithon , 1975 .