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Sample records for porites species coral

  1. Genetic species delineation among branching Caribbean Porites corals

    NASA Astrophysics Data System (ADS)

    Prada, C.; DeBiasse, M. B.; Neigel, J. E.; Yednock, B.; Stake, J. L.; Forsman, Z. H.; Baums, I. B.; Hellberg, M. E.

    2014-12-01

    Coral species are difficult to discern because of their morphological plasticity, long generation times, and slow rates of mitochondrial DNA evolution. Among Caribbean representatives of the genus Porites are three named species ( P. divaricata, P. furcata, and P. porites) with branching colony morphologies whose validity as genetically isolated species has been debated. We present sequence data from the mitochondrial control region, nuclear ITS, and nine single-copy nuclear loci for the Caribbean Porites and a related eastern Pacific species. mtDNA sequences were nearly invariant among the three branching species and their crustose sister P. branneri, and ITS sequences from these four were intermingled. An information theoretic analysis provided no support for upholding the three named Caribbean branching species. Both a clustering analysis and an analysis of molecular variance showed that sequence variation from the three branching forms is partitioned more by geography than by taxonomy. Multi-locus coalescent phylogenetic analysis provided a calibrated estimate for the nuclear DNA substitution rate (0.14 % Ma-1) close to that for other corals. Because no generalities have emerged from genetic investigations of the validity of morphologically defined coral species, the use of single-copy nuclear data is likely to be important in testing problematic species designations.

  2. Physiological and biogeochemical traits of bleaching and recovery in the mounding species of coral Porites lobata: implications for resilience in mounding corals.

    PubMed

    Levas, Stephen J; Grottoli, Andréa G; Hughes, Adam; Osburn, Christopher L; Matsui, Yohei

    2013-01-01

    Mounding corals survive bleaching events in greater numbers than branching corals. However, no study to date has determined the underlying physiological and biogeochemical trait(s) that are responsible for mounding coral holobiont resilience to bleaching. Furthermore, the potential of dissolved organic carbon (DOC) as a source of fixed carbon to bleached corals has never been determined. Here, Porites lobata corals were experimentally bleached for 23 days and then allowed to recover for 0, 1, 5, and 11 months. At each recovery interval a suite of analyses were performed to assess their recovery (photosynthesis, respiration, chlorophyll a, energy reserves, tissue biomass, calcification, δ(13)C of the skeletal, δ(13)C, and δ(15)N of the animal host and endosymbiont fractions). Furthermore, at 0 months of recovery, the assimilation of photosynthetically acquired and zooplankton-feeding acquired carbon into the animal host, endosymbiont, skeleton, and coral-mediated DOC were measured via (13)C-pulse-chase labeling. During the first month of recovery, energy reserves and tissue biomass in bleached corals were maintained despite reductions in chlorophyll a, photosynthesis, and the assimilation of photosynthetically fixed carbon. At the same time, P. lobata corals catabolized carbon acquired from zooplankton and seemed to take up DOC as a source of fixed carbon. All variables that were negatively affected by bleaching recovered within 5 to 11 months. Thus, bleaching resilience in the mounding coral P. lobata is driven by its ability to actively catabolize zooplankton-acquired carbon and seemingly utilize DOC as a significant fixed carbon source, facilitating the maintenance of energy reserves and tissue biomass. With the frequency and intensity of bleaching events expected to increase over the next century, coral diversity on future reefs may favor not only mounding morphologies but species like P. lobata, which have the ability to utilize heterotrophic sources of

  3. Physiological and Biogeochemical Traits of Bleaching and Recovery in the Mounding Species of Coral Porites lobata: Implications for Resilience in Mounding Corals

    PubMed Central

    Levas, Stephen J.; Grottoli, Andréa G.; Hughes, Adam; Osburn, Christopher L.; Matsui, Yohei

    2013-01-01

    Mounding corals survive bleaching events in greater numbers than branching corals. However, no study to date has determined the underlying physiological and biogeochemical trait(s) that are responsible for mounding coral holobiont resilience to bleaching. Furthermore, the potential of dissolved organic carbon (DOC) as a source of fixed carbon to bleached corals has never been determined. Here, Porites lobata corals were experimentally bleached for 23 days and then allowed to recover for 0, 1, 5, and 11 months. At each recovery interval a suite of analyses were performed to assess their recovery (photosynthesis, respiration, chlorophyll a, energy reserves, tissue biomass, calcification, δ13C of the skeletal, δ13C, and δ15N of the animal host and endosymbiont fractions). Furthermore, at 0 months of recovery, the assimilation of photosynthetically acquired and zooplankton-feeding acquired carbon into the animal host, endosymbiont, skeleton, and coral-mediated DOC were measured via 13C-pulse-chase labeling. During the first month of recovery, energy reserves and tissue biomass in bleached corals were maintained despite reductions in chlorophyll a, photosynthesis, and the assimilation of photosynthetically fixed carbon. At the same time, P. lobata corals catabolized carbon acquired from zooplankton and seemed to take up DOC as a source of fixed carbon. All variables that were negatively affected by bleaching recovered within 5 to 11 months. Thus, bleaching resilience in the mounding coral P. lobata is driven by its ability to actively catabolize zooplankton-acquired carbon and seemingly utilize DOC as a significant fixed carbon source, facilitating the maintenance of energy reserves and tissue biomass. With the frequency and intensity of bleaching events expected to increase over the next century, coral diversity on future reefs may favor not only mounding morphologies but species like P. lobata, which have the ability to utilize heterotrophic sources of fixed carbon

  4. Clues to unraveling the coral species problem: distinguishing species from geographic variation in Porites across the Pacific with molecular markers and microskeletal traits

    PubMed Central

    Wellington, Gerrard M.; Fox, George E.; Toonen, Robert J.

    2015-01-01

    Morphological variation in the geographically widespread coral Porites lobata can make it difficult to distinguish from other massive congeneric species. This morphological variation could be attributed to geographic variability, phenotypic plasticity, or a combination of such factors. We examined genetic and microscopic morphological variability in P. lobata samples from the Galápagos, Easter Island, Tahiti, Fiji, Rarotonga, and Australia. Panamanian P. evermanni specimens were used as a previously established distinct outgroup against which to test genetic and morphological methods of discrimination. We employed a molecular analysis of variance (AMOVA) based on ribosomal internal transcribed spacer region (ITS) sequence, principal component analysis (PCA) of skeletal landmarks, and Mantel tests to compare genetic and morphological variation. Both genetic and morphometric methods clearly distinguished P. lobata and P. evermanni, while significant genetic and morphological variance was attributed to differences among geographic regions for P. lobata. Mantel tests indicate a correlation between genetic and morphological variation for P. lobata across the Pacific. Here we highlight landmark morphometric measures that correlate well with genetic differences, showing promise for resolving species of Porites, one of the most ubiquitous yet challenging to identify architects of coral reefs. PMID:25674364

  5. Clues to unraveling the coral species problem: distinguishing species from geographic variation in Porites across the Pacific with molecular markers and microskeletal traits.

    PubMed

    Forsman, Zac; Wellington, Gerrard M; Fox, George E; Toonen, Robert J

    2015-01-01

    Morphological variation in the geographically widespread coral Porites lobata can make it difficult to distinguish from other massive congeneric species. This morphological variation could be attributed to geographic variability, phenotypic plasticity, or a combination of such factors. We examined genetic and microscopic morphological variability in P. lobata samples from the Galápagos, Easter Island, Tahiti, Fiji, Rarotonga, and Australia. Panamanian P. evermanni specimens were used as a previously established distinct outgroup against which to test genetic and morphological methods of discrimination. We employed a molecular analysis of variance (AMOVA) based on ribosomal internal transcribed spacer region (ITS) sequence, principal component analysis (PCA) of skeletal landmarks, and Mantel tests to compare genetic and morphological variation. Both genetic and morphometric methods clearly distinguished P. lobata and P. evermanni, while significant genetic and morphological variance was attributed to differences among geographic regions for P. lobata. Mantel tests indicate a correlation between genetic and morphological variation for P. lobata across the Pacific. Here we highlight landmark morphometric measures that correlate well with genetic differences, showing promise for resolving species of Porites, one of the most ubiquitous yet challenging to identify architects of coral reefs.

  6. Histological observations in the Hawaiian reef coral, Porites compressa, affected by Porites bleaching with tissue loss.

    PubMed

    Sudek, M; Work, T M; Aeby, G S; Davy, S K

    2012-10-01

    The scleractinian finger coral Porites compressa is affected by the coral disease Porites bleaching with tissue loss (PBTL). This disease initially manifests as bleaching of the coenenchyme (tissue between polyps) while the polyps remain brown with eventual tissue loss and subsequent algal overgrowth of the bare skeleton. Histopathological investigation showed a loss of symbiont and melanin-containing granular cells which was more pronounced in the coenenchyme than the polyps. Cell counts confirmed a 65% reduction in symbiont density. Tissue loss was due to tissue fragmentation and necrosis in affected areas. In addition, a reduction in putative bacterial aggregate densities was found in diseased samples but no potential pathogens were observed.

  7. Histological observations in the Hawaiian reef coral, Porites compressa, affected by Porites bleaching with tissue loss

    USGS Publications Warehouse

    Sudek, M.; Work, T.M.; Aeby, G.S.; Davy, S.K.

    2012-01-01

    The scleractinian finger coral Porites compressa is affected by the coral disease Porites bleaching with tissue loss (PBTL). This disease initially manifests as bleaching of the coenenchyme (tissue between polyps) while the polyps remain brown with eventual tissue loss and subsequent algal overgrowth of the bare skeleton. Histopathological investigation showed a loss of symbiont and melanin-containing granular cells which was more pronounced in the coenenchyme than the polyps. Cell counts confirmed a 65% reduction in symbiont density. Tissue loss was due to tissue fragmentation and necrosis in affected areas. In addition, a reduction in putative bacterial aggregate densities was found in diseased samples but no potential pathogens were observed.

  8. Physiological and Biogeochemical Traits of Bleaching and Recovery in the Mounding Species of Coral Porites lobata: Implications for Resilience in Mounding Corals

    DTIC Science & Technology

    2013-05-02

    biomass. With the frequency and intensity of bleaching events expected to increase over the next century, coral diversity on future reefs may favor not...Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina, United States of America Introduction Coral reefs are...coming decades [4,6,7], and are already causing mass coral reef decline worldwide [8]. Coral bleaching suscepti- bility has been directly linked to the

  9. Environmental controls on growth of the massive coral Porites.

    PubMed

    Lough; Barnes

    2000-03-15

    Annual density banding provided growth characteristics for 245 similar-sized, massive colonies of Porites from similar locations on 29 reefs from across the length and breadth of the Great Barrier Reef (GBR), Australia. Values obtained were density, extension rate, and calcification rate. Tissue thickness, the depth to which skeletons were occupied by tissue at the time of collection, was also measured. Extension rate, calcification rate, and tissue thickness were significantly greater at the top of colonies than at the sides. Extension rate and calcification rate decreased from north to south along the GBR (latitudinal range of approximately 9 degrees ) and were significantly and directly related to annual average sea surface temperature (SST; range approximately 25-27 degrees C). For each 1 degrees C rise in SST, average annual calcification increased by 0.39 g cm(-2) year(-1) and average annual extension increased by 3.1 mm year(-1) (c.f. average values of 1.63 g cm(-2) year(-1) and 12.9 mm year(-1), respectively). Density was inversely correlated with extension rate and increased with distance offshore. Data for massive Porites colonies from the GBR were extended though 20 degrees of latitude and an average annual SST range of 23-29 degrees C using published data for the Hawaiian Archipelago (Grigg, R.W., 1981. Coral reef development at high latitudes in Hawaii. Proc. 4th Int. Coral Reef Symp., Manila, Vol. 1, pp. 687-693; Grigg, R.W., 1997. Paleoceanography of coral reefs in the Hawaiian-Emperor Chain - revisited. Coral Reefs 16, S33-S38) and Phuket, Thailand (Scoffin. T.P., Tudhope. A.W., Brown. B.E., Chansang. H., Cheeney. R.F., 1992. Patterns and possible environmental controls of skeletogenesis of Porites lutea, South Thailand. Coral Reefs 11, 1-11). The response of calcification rate to temperature remained linear. Variation in annual average SST accounted for 84% of the variance. For each 1 degrees C rise in SST, average annual calcification increased by

  10. Evidence for the non-influence of salinity variability on the Porites coral Sr/Ca palaeothermometer

    NASA Astrophysics Data System (ADS)

    Moreau, M.; Corrège, T.; Dassié, E. P.; Le Cornec, F.

    2015-03-01

    Porites coral-based sea surface temperature (SST) reconstructions are obtained from the measurement of skeleton Sr/Ca ratio. However, the influence of salinity in the incorporation of these trace elements in the Porites aragonitic skeleton is still poorly documented. Laboratory experiments indicate that in three different coral species (not including the widely used Porites genus), salinity does not influence the Sr/Ca thermometer. In this study, we test the salinity effect on Porites Sr/Ca-based SST reconstructions at monthly and interannual timescales in open-ocean environmental conditions. We use a large spatial compilation of published Porites data from the Red Sea and Pacific and Indian oceans. Additionally to those published records, we add a new eastern Pacific coral Sr/Ca record from Clipperton Atoll. Using two different salinity products (Simple Ocean Data Assimilation (SODA) SSS reanalyses version 2.2.4, Carton and Giese, 2008; and instrumental SSS from the Institut de Recherche pour le Développement, France (IRD) Delcroix et al., 2011), we find no evidence of salinity bias on the Sr/Ca SST proxy at monthly and interannual timescales. We conclude that Porites Sr/Ca is a reliable palaeothermometer that is not influenced by salinity variability.

  11. Shape-shifting corals: Molecular markers show morphology is evolutionarily plastic in Porites

    PubMed Central

    Forsman, Zac H; Barshis, Daniel J; Hunter, Cynthia L; Toonen, Robert J

    2009-01-01

    Background Corals are notoriously difficult to identify at the species-level due to few diagnostic characters and variable skeletal morphology. This 'coral species problem' is an impediment to understanding the evolution and biodiversity of this important and threatened group of organisms. We examined the evolution of the nuclear ribosomal internal transcribed spacer (ITS) and mitochondrial markers (COI, putative control region) in Porites, one of the most taxonomically challenging and ecologically important genera of reef-building corals. Results Nuclear and mitochondrial markers were congruent, clearly resolving many traditionally recognized species; however, branching and mounding varieties were genetically indistinguishable within at least two clades, and specimens matching the description of 'Porites lutea' sorted into three genetically divergent groups. Corallite-level features were generally concordant with genetic groups, although hyper-variability in one group (Clade I) overlapped and obscured several others, and Synarea (previously thought to be a separate subgenus) was closely related to congeners despite its unique morphology. Scanning electron microscopy revealed subtle differences between genetic groups that may have been overlooked previously as taxonomic characters. Conclusion This study demonstrates that the coral skeleton can be remarkably evolutionarily plastic, which may explain some taxonomic difficulties, and obscure underlying patterns of endemism and diversity. PMID:19239678

  12. Metagenomic analysis of the microbial community associated with the coral Porites astreoides.

    PubMed

    Wegley, Linda; Edwards, Robert; Rodriguez-Brito, Beltran; Liu, Hong; Rohwer, Forest

    2007-11-01

    The coral holobiont is a dynamic assemblage of the coral animal, zooxanthellae, endolithic algae and fungi, Bacteria,Archaea and viruses. Zooxanthellae and some Bacteria form relatively stable and species-specific associations with corals. Other associations are less specific; coral-associated Archaea differ from those in the water column, but the same archaeal species may be found on different coral species. It has been hypothesized that the coral animal can adapt to differing ecological niches by 'switching' its microbial associates. In the case of corals and zooxanthellae, this has been termed adaptive bleaching and it has important implications for carbon cycling within the coral holobiont and ultimately the survival of coral reefs. However, the roles of other components of the coral holobiont are essentially unknown. To better understand these other coral associates, a fractionation procedure was used to separate the microbes, mitochondria and viruses from the coral animal cells and zooxanthellae. The resulting metagenomic DNA was sequenced using pyrosequencing. Fungi, Bacteria and phage were the most commonly identified organisms in the metagenome. Three of the four fungal phyla were represented, including a wide diversity of fungal genes involved in carbon and nitrogen metabolism, suggesting that the endolithic community is more important than previously appreciated. In particular, the data suggested that endolithic fungi could be converting nitrate and nitrite to ammonia, which would enable fixed nitrogen to cycle within the coral holobiont. The most prominent bacterial groups were Proteobacteria (68%), Firmicutes (10%), Cyanobacteria (7%) and Actinobacteria (6%). Functionally, the bacterial community was primarily heterotrophic and included a number of pathways for the degradation of aromatic compounds, the most abundant being the homogentisate pathway. The most abundant phage family was the ssDNA Microphage and most of the eukaryotic viruses were most

  13. Highly heterogeneous bacterial communities associated with the South China Sea reef corals Porites lutea, Galaxea fascicularis and Acropora millepora.

    PubMed

    Li, Jie; Chen, Qi; Zhang, Si; Huang, Hui; Yang, Jian; Tian, Xin-Peng; Long, Li-Juan

    2013-01-01

    Coral harbor diverse and specific bacteria play significant roles in coral holobiont function. Bacteria associated with three of the common and phylogenetically divergent reef-building corals in the South China Sea, Porites lutea, Galaxea fascicularis and Acropora millepora, were investigated using 454 barcoded-pyrosequencing. Three colonies of each species were sampled, and 16S rRNA gene libraries were constructed individually. Analysis of pyrosequencing libraries showed that bacterial communities associated with the three coral species were more diverse than previous estimates based on corals from the Caribbean Sea, Indo-Pacific reefs and the Red Sea. Three candidate phyla, including BRC1, OD1 and SR1, were found for the first time in corals. Bacterial communities were separated into three groups: P. lutea and G. fascicular, A. millepora and seawater. P. lutea and G. fascicular displayed more similar bacterial communities, and bacterial communities associated with A. millepora differed from the other two coral species. The three coral species shared only 22 OTUs, which were distributed in Alphaproteobacteria, Deltaproteobacteria, Gammaproteobacteria, Chloroflexi, Actinobacteria, Acidobacteria and an unclassified bacterial group. The composition of bacterial communities within each colony of each coral species also showed variation. The relatively small common and large specific bacterial communities in these corals implies that bacterial associations may be structured by multiple factors at different scales and that corals may associate with microbes in terms of similar function, rather than identical species.

  14. Effects of intermittent flow and irradiance level on back reef Porites corals at elevated seawater temperatures

    USGS Publications Warehouse

    Smith, L.W.; Birkeland, C.

    2007-01-01

    Corals inhabiting shallow back reef habitats are often simultaneously exposed to elevated seawater temperatures and high irradiance levels, conditions known to cause coral bleaching. Water flow in many tropical back reef systems is tidally influenced, resulting in semi-diurnal or diurnal flow patterns. Controlled experiments were conducted to test effects of semi-diurnally intermittent water flow on photoinhibition and bleaching of the corals Porites lobata and P. cylindrica kept at elevated seawater temperatures and different irradiance levels. All coral colonies were collected from a shallow back reef pool on Ofu Island, American Samoa. In the high irradiance experiments, photoinhibition and bleaching were less for both species in the intermittent high-low flow treatment than in the constant low flow treatment. In the low irradiance experiments, there were no differences in photoinhibition or bleaching for either species between the flow treatments, despite continuously elevated seawater temperatures. These results suggest that intermittent flow associated with semi-diurnal tides, and low irradiances caused by turbidity or shading, may reduce photoinhibition and bleaching of back reef corals during warming events. ?? 2006 Elsevier B.V. All rights reserved.

  15. Contrasting Lesion Dynamics of White Syndrome among the scleractinian corals Porites spp

    PubMed Central

    Lozada-Misa, Paula; Kerr, Alexander; Raymundo, Laurie

    2015-01-01

    White syndrome (WS) is currently the most prevalent disease of scleractinian corals in the Indo-Pacific region, with an ability to exist in both epizootic and enzootic states. Here, we present results of an examination of WS lesion dynamics and show that potentially associated traits of host morphology (i.e., branching vs. massive), lesion size, and tissue deposition rate influence disease severity and recovery. Lesion healing rate was positively correlated with initial lesion size in both morphologies, but the rate at which lesions healed differed between morphologies. New lesions in branching Porites cylindrica appeared less frequently, were smaller and healed more quickly, but were more abundant than in closely-related massive Porites sp(p). The positive association between lesion size and healing rate was partly explained by geometry; branching limited lesion maximum size, and larger lesion margins contained more polyps producing new tissue, resulting in faster healing. However, massive colonies deposited tissue more slowly than branching colonies, resulting in slower recovery and more persistent lesions. Corallite size and density did not differ between species and did not, therefore, influence healing rate. We demonstrated multiple modes of pathogen transmission, which may be influenced by the greater potential for pathogen entrainment in branching vs. massive morphologies. We suggest that attributes such as colony morphology and species-specific growth rates require consideration as we expand our understanding of disease dynamics in colonial organisms such as coral. PMID:26120844

  16. The complete mitochondrial DNA of endemic Eastern Pacific coral (Porites panamensis).

    PubMed

    Del Río-Portilla, Miguel A; Vargas-Peralta, Carmen E; Paz-García, David A; Lafarga De La Cruz, Fabiola; Balart, Eduardo F; García-de-León, Francisco J

    2016-01-01

    The mitogenome of the endemic coral Porites panamensis (Genbank accession number KJ546638) has a total length of 18,628 bp, and the arrangement consist of 13 protein-coding genes, 2 ribosomal RNA (rRNA) genes and 2 transfer RNA (tRNA) genes. Gene order was equal to other scleractinian coral mitogenomes.

  17. Bacterial communities associated with Porites white patch syndrome (PWPS) on three western Indian Ocean (WIO) coral reefs.

    PubMed

    Séré, Mathieu G; Tortosa, Pablo; Chabanet, Pascale; Turquet, Jean; Quod, Jean-Pascal; Schleyer, Michael H

    2013-01-01

    The scleractinian coral Porites lutea, an important reef-building coral on western Indian Ocean reefs (WIO), is affected by a newly-reported white syndrome (WS) the Porites white patch syndrome (PWPS). Histopathology and culture-independent molecular techniques were used to characterise the microbial communities associated with this emerging disease. Microscopy showed extensive tissue fragmentation generally associated with ovoid basophilic bodies resembling bacterial aggregates. Results of 16S rRNA sequence analysis revealed a high variability between bacterial communities associated with PWPS-infected and healthy tissues in P. lutea, a pattern previously reported in other coral diseases such as black band disease (BBD), white band disease (WBD) and white plague diseases (WPD). Furthermore, substantial variations in bacterial communities were observed at the different sampling locations, suggesting that there is no strong bacterial association in Porites lutea on WIO reefs. Several sequences affiliated with potential pathogens belonging to the Vibrionaceae and Rhodobacteraceae were identified, mainly in PWPS-infected coral tissues. Among them, only two ribotypes affiliated to Shimia marina (NR043300.1) and Vibrio hepatarius (NR025575.1) were consistently found in diseased tissues from the three geographically distant sampling localities. The role of these bacterial species in PWPS needs to be tested experimentally.

  18. The Shifts of Diazotrophic Communities in Spring and Summer Associated with Coral Galaxea astreata, Pavona decussata, and Porites lutea

    PubMed Central

    Zhang, Yanying; Yang, Qingsong; Ling, Juan; Van Nostrand, Joy D.; Shi, Zhou; Zhou, Jizhong; Dong, Junde

    2016-01-01

    The coral holobiont often resides in oligotrophic waters; both coral cells and their symbiotic dinoflagellates possess ammonium assimilation enzymes and potentially benefit from the nitrogen fixation of coral-associated diazotrophs. However, the seasonal dynamics of coral-associated diazotrophs are not well characterized. Here, the seasonal variations of diazotrophic communities associated with three corals, Galaxea astreata, Pavona decussata, and Porites lutea, were studied using nifH gene amplicon pyrosequencing techniques. Our results revealed a great diversity of coral-associated diazotrophs. nifH sequences related to Alphaproteobacteria, Deltaproteobacteria, and Gammaproteobacteria were ubiquitous and dominant in all corals in two seasons. In contrast with the coral P. decussata, both G. astreata and P. lutea showed significant seasonal changes in the diazotrophic communities and nifH gene abundance. Variable diazotroph groups accounted for a range from 11 to 49% within individual coral samples. Most of the variable diazotrophic groups from P. decussata were species-specific, however, the majority of overlapping variable groups in G. astreata and P. lutea showed the same seasonal variation characteristics. Rhodopseudomonas palustris- and Gluconacetobacter diazotrophicus-affiliated sequences were relatively abundant in the summer, whereas a nifH sequence related to Halorhodospira halophila was relatively abundant in spring G. astreata and P. lutea. The seasonal variations of all diazotrophic communities were significantly correlated with the seasonal shifts of ammonium and nitrate, suggesting that diazotrophs play an important role in the nitrogen cycle of the coral holobiont. PMID:27920768

  19. High-Resolution Synchrotron Radiation Imaging of Trace Metal Elemental Concentrations in Porites Coral

    NASA Astrophysics Data System (ADS)

    Cirino, M.; Dunbar, R. B.; Tangri, N.; Mehta, A.

    2014-12-01

    We investigated the use of synchrotron radiation for elemental imaging within the skeleton of a Porites coral from American Samoa to explore the fine-scale structure of strontium to calcium (Sr/Ca) variability. The use of a synchrotron for coral paleoclimate analysis is relatively new. The method provides a high resolution, two-dimensional elemental map of a coral surface. The aragonitic skeleton of Porites sp. colonies has been widely used for paleoclimate reconstruction as the oxygen isotope ratio (δ18O) signal varies with both sea surface temperature (SST) and sea surface salinity (SSS). Sr/Ca has been used in previous studies in conjunction with δ18O to deconvolve SST from SSS, as Sr/Ca in the coral skeleton varies with SST, but not SSS. However, recent studies suggest that in some cases Sr/Ca variability in coral does not reliably reflect changes in SST. We sought to address this puzzle by investigating Sr/Ca variability in Porites corals at a very fine spatial scale while also demonstrating the suitability of the synchrotron as a coral analysis tool. We also considered Sr/Ca variability as it pertains to the coral's structural elements. The Stanford Linear Accelerator Center synchrotron station generates collimated x-rays in the energy range of 4500-45000 eV with beam diameters as small as 20 μm. Synchrotron imaging allows faster and higher-resolution Sr/Ca analysis than does inductively coupled plasma mass spectrometry (ICP-MS). It also is capable of mapping spatial distributions of many elements, which aids in the development of a multiproxy approach to paleoclimate reconstruction. Imaging and analysis of the Porites coral using synchrotron radiation revealed an intricate sub-seasonal Sr/Ca signal, possibly correlating to a sub-monthly resolution. This signal, which seems unrelated to SST, dominates the annual signal.

  20. Unrecognized coral species diversity masks differences in functional ecology.

    PubMed

    Boulay, Jennifer N; Hellberg, Michael E; Cortés, Jorge; Baums, Iliana B

    2014-02-07

    Porites corals are foundation species on Pacific reefs but a confused taxonomy hinders understanding of their ecosystem function and responses to climate change. Here, we show that what has been considered a single species in the eastern tropical Pacific, Porites lobata, includes a morphologically similar yet ecologically distinct species, Porites evermanni. While P. lobata reproduces mainly sexually, P. evermanni dominates in areas where triggerfish prey on bioeroding mussels living within the coral skeleton, thereby generating asexual coral fragments. These fragments proliferate in marginal habitat not colonized by P. lobata. The two Porites species also show a differential bleaching response despite hosting the same dominant symbiont subclade. Thus, hidden diversity within these reef-builders has until now obscured differences in trophic interactions, reproductive dynamics and bleaching susceptibility, indicative of differential responses when confronted with future climate change.

  1. Unrecognized coral species diversity masks differences in functional ecology

    PubMed Central

    Boulay, Jennifer N.; Hellberg, Michael E.; Cortés, Jorge; Baums, Iliana B.

    2014-01-01

    Porites corals are foundation species on Pacific reefs but a confused taxonomy hinders understanding of their ecosystem function and responses to climate change. Here, we show that what has been considered a single species in the eastern tropical Pacific, Porites lobata, includes a morphologically similar yet ecologically distinct species, Porites evermanni. While P. lobata reproduces mainly sexually, P. evermanni dominates in areas where triggerfish prey on bioeroding mussels living within the coral skeleton, thereby generating asexual coral fragments. These fragments proliferate in marginal habitat not colonized by P. lobata. The two Porites species also show a differential bleaching response despite hosting the same dominant symbiont subclade. Thus, hidden diversity within these reef-builders has until now obscured differences in trophic interactions, reproductive dynamics and bleaching susceptibility, indicative of differential responses when confronted with future climate change. PMID:24335977

  2. Characterization of Geographically Distinct Bacterial Communities Associated with Coral Mucus Produced by Acropora spp. and Porites spp.

    PubMed Central

    McKew, B. A.; Dumbrell, A. J.; Daud, S. D.; Hepburn, L.; Thorpe, E.; Mogensen, L.

    2012-01-01

    Acropora and Porites corals are important reef builders in the Indo-Pacific and Caribbean. Bacteria associated with mucus produced by Porites spp. and Acropora spp. from Caribbean (Punta Maroma, Mexico) and Indo-Pacific (Hoga and Sampela, Indonesia) reefs were determined. Analysis of pyrosequencing libraries showed that bacterial communities from Caribbean corals were significantly more diverse (H′, 3.18 to 4.25) than their Indonesian counterparts (H′, 2.54 to 3.25). Dominant taxa were Gammaproteobacteria, Alphaproteobacteria, Firmicutes, and Cyanobacteria, which varied in relative abundance between coral genera and region. Distinct coral host-specific communities were also found; for example, Clostridiales were dominant on Acropora spp. (at Hoga and the Mexican Caribbean) compared to Porites spp. and seawater. Within the Gammproteobacteria, Halomonas spp. dominated sequence libraries from Porites spp. (49%) and Acropora spp. (5.6%) from the Mexican Caribbean, compared to the corresponding Indonesian coral libraries (<2%). Interestingly, with the exception of Porites spp. from the Mexican Caribbean, there was also a ubiquity of Psychrobacter spp., which dominated Acropora and Porites libraries from Indonesia and Acropora libraries from the Caribbean. In conclusion, there was a dominance of Halomonas spp. (associated with Acropora and Porites [Mexican Caribbean]), Firmicutes (associated with Acropora [Mexican Caribbean] and with Acropora and Porites [Hoga]), and Cyanobacteria (associated with Acropora and Porites [Hoga] and Porites [Sampela]). This is also the first report describing geographically distinct Psychrobacter spp. associated with coral mucus. In addition, the predominance of Clostridiales associated with Acropora spp. provided additional evidence for coral host-specific microorganisms. PMID:22636010

  3. Coral diseases on Philippine reefs: genus Porites is a dominant host.

    PubMed

    Raymundo, Laurie J; Rosell, Kathryn B; Reboton, Clarissa T; Kaczmarsky, Longin

    2005-05-20

    While it is generally assumed that Indo-Pacific reefs are not widely affected by diseases, limited data suggest a number of diseases and syndromes that appear to differ from those currently under study in the Caribbean. This report presents the results of a baseline survey of coral diseases in 2 regions in the Philippines: the Central Visayas and the Lingayen Gulf. Mean prevalence for all diseases observed was 8.3 +/- 1.2% (mean +/- SE; n = 8 reefs), with Central Visayas reefs showing higher disease prevalence (11.6 +/- 2.8%; n = 4 reefs) than those of Lingayen Gulf (5.1 +/- 1.4%; n = 4 reefs). Five diseases and syndromes were described; 3 of these-Porites ulcerative white spot disease (PUWS) (prevalence = 8.96 +/- 2.2%), tumors (prevalence = 1.0 +/- 0.5%) and pigmentation response (prevalence = 0.5 +/- 0.2%)--occurred frequently in both regions and targeted the genus Porites. Correlation between disease prevalence and number of Porites colonies was fairly strong (r2 = 43.4), though not significant, and no correlation was seen between prevalence and either the amount or diversity of hard coral. Porites is a major reef-builder in the Indo-Pacific comprising 30% of hard coral colonies on our surveyed reefs, and is generally thought to be a hardy, long-lived genus. Diseases targeting this robust group present an as yet unquantified risk to Philippine reefs and could result in major changes in reef structure.

  4. Trace metal anomalies in bleached Porites coral at Meiji Reef, tropical South China Sea

    NASA Astrophysics Data System (ADS)

    Li, Shu; Yu, Kefu; Zhao, Jianxin; Feng, Yuexing; Chen, Tianran

    2017-01-01

    Coral bleaching has generally been recognized as the main reason for tropical coral reef degradation, but there are few long-term records of coral bleaching events. In this study, trace metals including chromium (Cr), copper (Cu), molybdenum (Mo), manganese (Mn), lead (Pb), tin (Sn), titanium (Ti), vanadium (V), and yttrium (Y), were analyzed in two Porites corals collected from Meiji Reef in the tropical South China Sea (SCS) to assess differences in trace metal concentrations in bleached compared with unbleached coral growth bands. Ti, V, Cr, and Mo generally showed irregular fluctuations in both corals. Bleached layers contained high concentrations of Mn, Cu, Sn, and Pb. Unbleached layers showed moderately high concentrations of Mn and Cu only. The different distribution of trace metals in Porites may be attributable to different selectivity on the basis of vital utility or toxicity. Ti, V, Cr, and Mo are discriminated against by both coral polyps and zooxanthellae, but Mn, Cu, Sn, and Pb are accumulated by zooxanthellae and only Mn and Cu are accumulated by polyps as essential elements. The marked increase in Cu, Mn, Pb, and Sn are associated with bleaching processes, including mucus secretion, tissue retraction, and zooxanthellae expulsion and occlusion. Variation in these trace elements within the coral skeleton can be used as potential tracers of short-lived bleaching events.

  5. Chemically mediated interactions between macroalgae Dictyota spp. and multiple life-history stages of the coral Porites astreoides

    USGS Publications Warehouse

    Paul, V.J.; Kuffner, I.B.; Walters, L.J.; Ritson-Williams, R.; Beach, K.S.; Becerro, M.A.

    2011-01-01

    Competition between corals and macroalgae is often assumed to occur on reefs, especially those that have undergone shifts from coral to algal dominance; however, data examining these competitive interactions, especially during the early life-history stages of corals, are scarce. We conducted a series of field and outdoor seawater-table experiments to test the hypothesis that allelopathy (chemical inhibition) mediates interactions between 2 common brown macroalgae, Dictyota pulchella and D. pinnatifida, and the coral Porites astreoides at different life-history stages of the coral. D. pinnatifida significantly reduced larval survival and larval recruitment. The extracts of both D. pinnatifida and D. pulchella significantly reduced larval survival, and the extract of D. pulchella also negatively influenced larval recruitment. There was no measurable effect of the crude extracts from Dictyota spp. on the photophysiology of adult corals. Our results provide evidence that these Dictyota species chemically compete with P. astreoides by negatively affecting larval settlement and recruitment as well as the survival of larvae and new recruits. Macroalgae may perpetuate their dominance on degraded reefs by chemically inhibiting the process of coral recruitment. ?? 2011 Inter-Research.

  6. Chemically-mediated interactions between macroalgae Dictyota spp. and multiple life-history stages of the coral Porites astreoides

    USGS Publications Warehouse

    Paul, Valerie J.; Kuffner, Ilsa B.; Walters, Linda J.; Ritson-Williams, Raphael; Beach, Kevin S.; Becerro, Mikel A.

    2011-01-01

    Competition between corals and macroalgae is often assumed to occur on reefs, especially those that have undergone shifts from coral to algal dominance; however, data examining these competitive interactions, especially during the early life-history stages of corals, are scarce. We conducted a series of field and outdoor seawater-table experiments to test the hypothesis that allelopathy (chemical inhibition) mediates interactions between 2 common brown macroalgae, Dictyota pulchella and D. pinnatifida, and the coral Porites astreoides at different life-history stages of the coral. D. pinnatifida significantly reduced larval survival and larval recruitment. The extracts of both D. pinnatifida and D. pulchella significantly reduced larval survival, and the extract of D. pulchella also negatively influenced larval recruitment. There was no measurable effect of the crude extracts from Dictyota spp. on the photophysiology of adult corals. Our results provide evidence that these Dictyota species chemically compete with P. astreoides by negatively affecting larval settlement and recruitment as well as the survival of larvae and new recruits. Macroalgae may perpetuate their dominance on degraded reefs by chemically inhibiting the process of coral recruitment.

  7. Quantification of virus-like particles suggests viral infection in corals affected by Porites tissue loss

    NASA Astrophysics Data System (ADS)

    Lawrence, Scott A.; Davy, Joanne E.; Aeby, Greta S.; Wilson, William H.; Davy, Simon K.

    2014-09-01

    Porites tissue loss is a common disease of Porites compressa on Hawaiian reefs. Despite its prevalence, to date, the aetiological agent of the disease has not been found. The apparent lack of a microbial causative agent in the similar disease Porites bleaching with tissue loss, as well as increasing evidence of viral infections in scleractinian corals and Symbiodinium, led us to hypothesise that a virus may be responsible. Electron microscopy revealed the presence of numerous and varied virus-like particles (VLPs) in healthy and diseased P. compressa colonies. While overall virus numbers were similar in all samples, the abundance of a group of icosahedral VLPs differed significantly between healthy and diseased colonies. While not conclusive, these results suggest that viruses may play a role in this disease, and provide a basis for further studies.

  8. Community Shifts in the Surface Microbiomes of the Coral Porites astreoides with Unusual Lesions

    PubMed Central

    Meyer, Julie L.; Paul, Valerie J.; Teplitski, Max

    2014-01-01

    Apical lesions on Porites astreoides were characterized by the appearance of a thin yellow band, which was preceded by bleaching of the coral tissues and followed by a completely denuded coral skeleton, which often harbored secondary macroalgal colonizers. These characteristics have not been previously described in Porites and do not match common Caribbean coral diseases. The lesions were observed only in warmer months and at shallow depths on the fore reef in Belize. Analysis of the microbial community composition based on the V4 hypervariable region of 16S ribosomal RNA genes revealed that the surface microbiomes associated with nonsymptomatic corals were dominated by the members of the genus Endozoicomonas, consistent with other studies. Comparison of the microbiomes of nonsymptomatic and lesioned coral colonies sampled in July and September revealed two distinct groups, inconsistently related to the disease state of the coral, but showing some temporal signal. The loss of Endozoicomonas was characteristic of lesioned corals, which also harbored potential opportunistic pathogens such as Alternaria, Stenotrophomonas, and Achromobacter. The presence of lesions in P. astreoides coincided with a decrease in the relative abundance of Endozoicomonas, rather than the appearance of specific pathogenic taxa. PMID:24937478

  9. Seasonal changes in bacterial communities associated with healthy and diseased Porites coral in southern Taiwan.

    PubMed

    Lin, Chorng-Horng; Chuang, Chih-Hsiang; Twan, Wen-Hung; Chiou, Shu-Fen; Wong, Tit-Yee; Liu, Jong-Kang; Kao, Chyuan-Yao; Kuo, Jimmy

    2016-12-01

    We compared the bacterial communities associated with healthy scleractinian coral Porites sp. with those associated with coral infected with pink spot syndrome harvested during summer and winter from waters off the coast of southern Taiwan. Members of the bacterial community associated with the coral were characterized by means of denaturing gradient gel electrophoresis (DGGE) of a short region of the 16S rRNA gene and clone library analysis. Of 5 different areas of the 16S rRNA gene, we demonstrated that the V3 hypervariable region is most suited to represent the coral-associated bacterial community. The DNA sequences of 26 distinct bands extracted from DGGE gels and 269 sequences of the 16S rRNA gene from clone libraries were determined. We found that the communities present in diseased coral were more heterogeneous than the bacterial communities of uninfected coral. In addition, bacterial communities associated with coral harvested in the summer were more diverse than those associated with coral collected in winter, regardless of the health status of the coral. Our study suggested that the compositions of coral-associated bacteria communities are complex, and the population of bacteria varies greatly between seasons and in coral of differing health status.

  10. Skeletal records of community-level bleaching in Porites corals from Palau

    NASA Astrophysics Data System (ADS)

    Barkley, Hannah C.; Cohen, Anne L.

    2016-12-01

    Tropical Pacific sea surface temperature is projected to rise an additional 2-3 °C by the end of this century, driving an increase in the frequency and intensity of coral bleaching. With significant global coral reef cover already lost due to bleaching-induced mortality, efforts are underway to identify thermally tolerant coral communities that might survive projected warming. Massive, long-lived corals accrete skeletal bands of anomalously high density in response to episodes of thermal stress. These "stress bands" are potentially valuable proxies for thermal tolerance, but to date their application to questions of community bleaching history has been limited. Ecological surveys recorded bleaching of coral communities across the Palau archipelago during the 1998 and 2010 warm events. Between 2011 and 2015, we extracted skeletal cores from living Porites colonies at 10 sites spanning barrier reef and lagoon environments and quantified the proportion of stress bands present in each population during bleaching years. Across Palau, the prevalence of stress bands tracked the severity of thermal stress, with more stress bands occurring in 1998 (degree heating weeks = 13.57 °C-week) than during the less severe 2010 event (degree heating weeks = 4.86 °C-week). Stress band prevalence also varied by reef type, as more corals on the exposed barrier reef formed stress bands than did corals from sheltered lagoon environments. Comparison of Porites stress band prevalence with bleaching survey data revealed a strong correlation between percent community bleaching and the proportion of colonies with stress bands in each year. Conversely, annual calcification rates did not decline consistently during bleaching years nor did annually resolved calcification histories always track interannual variability in temperature. Our data suggest that stress bands in massive corals contain valuable information about spatial and temporal trends in coral reef bleaching and can aid in

  11. Parrotfish predation on massive Porites on the Great Barrier Reef

    NASA Astrophysics Data System (ADS)

    Bonaldo, R. M.; Bellwood, D. R.

    2011-03-01

    Parrotfish grazing scars on coral colonies were quantified across four reef zones at Lizard Island, Northern Great Barrier Reef (GBR). The abundance of parrotfish grazing scars was highest on reef flat and crest, with massive Porites spp . colonies having more parrotfish grazing scars than all other coral species combined. Massive Porites was the only coral type positively selected for grazing by parrotfishes in all four reef zones. The density of parrotfish grazing scars on massive Porites spp., and the rate of new scar formation, was highest on the reef crest and flat, reflecting the lower massive Porites cover and higher parrotfish abundance in these habitats. Overall, it appears that parrotfish predation pressure on corals could affect the abundance of preferred coral species, especially massive Porites spp , across the reef gradient. Parrotfish predation on corals may have a more important role on the GBR reefs than previously thought.

  12. The effect of changes in sea surface temperature on linear growth of Porites coral in Ambon Bay

    SciTech Connect

    Corvianawatie, Corry Putri, Mutiara R.; Cahyarini, Sri Y.

    2015-09-30

    Coral is one of the most important organisms in the coral reef ecosystem. There are several factors affecting coral growth, one of them is changes in sea surface temperature (SST). The purpose of this research is to understand the influence of SST variability on the annual linear growth of Porites coral taken from Ambon Bay. The annual coral linear growth was calculated and compared to the annual SST from the Extended Reconstructed Sea Surface Temperature version 3b (ERSST v3b) model. Coral growth was calculated by using Coral X-radiograph Density System (CoralXDS) software. Coral sample X-radiographs were used as input data. Chronology was developed by calculating the coral’s annual growth bands. A pair of high and low density banding patterns observed in the coral’s X-radiograph represent one year of coral growth. The results of this study shows that Porites coral extents from 2001-2009 and had an average growth rate of 1.46 cm/year. Statistical analysis shows that the annual coral linear growth declined by 0.015 cm/year while the annual SST declined by 0.013°C/year. SST and the annual linear growth of Porites coral in the Ambon Bay is insignificantly correlated with r=0.304 (n=9, p>0.05). This indicates that annual SST variability does not significantly influence the linear growth of Porites coral from Ambon Bay. It is suggested that sedimentation load, salinity, pH or other environmental factors may affect annual linear coral growth.

  13. Cellular physiological effects of the MV Kyowa violet fuel-oil spill on the hard coral, Porites lobata.

    PubMed

    Downs, Craig A; Richmond, Robert H; Mendiola, Woon Jaye; Rougée, Luc; Ostrander, Gary K

    2006-12-01

    The grounding of the Merchant Vessel (MV) Kyowa Violet on a coral reef near Yap, Federated States of Micronesia, in December 2002 resulted in the release of an estimated 55,000 to 80,000 gallons of intermediate fuel oil grade 180. The immediate impact was the widespread coating of mangroves and the intertidal zone along more than 8 km of coastline. Of greater concern, however, was the partitioning of the fuel oil in the water column, leading to chronic exposure of organisms in the ecosystem for a considerable period after the initial event. Herein, we report on our examination of one coral species, Porites lobata, nearly three months after the initial exposure. We investigated whether changes in cellular physiology were consistent with the pathological profile that results from the interaction of corals with polycyclic aromatic hydrocarbons, the principal constituent of fuel oil. Specifically, we document, to our knowledge for the first time, changes in the cellular physiological condition of an exposed coral population affected by a fuel-oil spill. We also provide evidence that the observed changes are consistent with a recent exposure to fuel oil, as evidenced by the presence of characteristic cellular lesions attributed to polycyclic aromatic hydrocarbons. Finally, our data support a model for a mechanistic relationship between the cellular pathological profile of the coral and a recent petroleum exposure, such as the MV Kyowa Violet fuel oil spill.

  14. Autotrophic and heterotrophic responses of the coral Porites lutea to large amplitude internal waves.

    PubMed

    Pacherres, Cesar O; Schmidt, Gertraud M; Richter, Claudio

    2013-12-01

    Large amplitude internal waves (LAIW) cause frequent and severe changes in the physico-chemical environment of Andaman Sea coral reefs and are a potentially important source of disturbance for corals. To explore the coral response to LAIW, prey capture disposition and photosynthesis were investigated in relation to changes in seawater temperature, pH, flow speed and food availability in LAIW simulation studies under controlled laboratory conditions, using Porites lutea as a model organism. Although food presence stimulated polyp expansion, we found an overriding effect of low temperature (19°C) causing retraction of the coral polyps into their calices, particularly when pH was altered concomitantly. Decreases in pH alone, however, caused the expansion of the polyps. The exposure history of the colonies played a crucial role in coral responses: prior field exposure to LAIW yielded lower retraction levels than in LAIW-inexperienced corals, suggesting acclimatization. Low temperature (19°C) exposure did not seem to influence the photosynthetic performance, but LAIW-experienced corals showed higher values of maximum dark-adapted quantum yield (Fv/Fm) of photosystem II than LAIW-inexperienced controls. Collectively, these data suggest that P. lutea, the dominant hermatypic coral in the Andaman Sea, can acclimatize to extreme changes in its abiotic environment by modulating its mixotrophic nutrition, through polyp expansion and potential feeding, as well as its photosynthetic efficiency.

  15. Coral growth and bioerosion of Porites lutea in response to large amplitude internal waves.

    PubMed

    Schmidt, Gertraud Maria; Richter, Claudio

    2013-01-01

    The Similan Islands (Thailand) in the Andaman Sea are exposed to large amplitude internal waves (LAIW), as evidenced by i.a. abrupt fluctuations in temperature of up to 10°C at supertidal frequencies. Although LAIW have been shown to affect coral composition and framework development in shallow waters, the role of LAIW on coral growth is so far unknown. We carried out a long-term transplant experiment with live nubbins and skeleton slabs of the dominating coral Porites lutea to assess the net growth and bioerosion in LAIW-exposed and LAIW-protected waters. Depth-related, seasonal and interannual differences in LAIW-intensities on the exposed western sides of the islands allowed us to separate the effect of LAIW from other possible factors (e.g. monsoon) affecting the corals. Coral growth and bioerosion were inversely related to LAIW intensity, and positively related to coral framework development. Accretion rates of calcareous fouling organisms on the slabs were negligible compared to bioerosion, reflecting the lack of a true carbonate framework on the exposed W faces of the Similan Islands. Our findings show that LAIW may play an important, yet so far overlooked, role in controlling coral growth in tropical waters.

  16. Clustered parrotfish feeding scars trigger partial coral mortality of massive Porites colonies on the inshore Great Barrier Reef

    NASA Astrophysics Data System (ADS)

    Welsh, J. Q.; Bonaldo, R. M.; Bellwood, D. R.

    2015-03-01

    Coral predation by parrotfishes can cause damage to coral colonies, but research into the dynamics of their feeding scars on Indo-Pacific corals is limited. We monitored feeding scars of the parrotfish Chlorurus microrhinos on massive Porites colonies at Orpheus Island (inshore Great Barrier Reef) over 4 months. Of the 30 marks monitored, 11 were single feeding scars, which all healed completely. The remaining 19 feeding marks consisted of clusters of scars. Eight began to recover, while 11 increased in size by 1,576 ± 252 % (mean ± SE). A logistic regression predicted that a single feeding scar on a Porites colony had a 97 % probability of healing; however, where more than three feeding scars were present, this dropped below 50 %. As excavating parrotfishes in the Indo-Pacific often take multiple focused bites, they may have a significant impact on the growth and mortality of massive Porites colonies at Orpheus Island.

  17. Model suggests potential for Porites coral population recovery after removal of anthropogenic disturbance (Luhuitou, Hainan, South China Sea)

    PubMed Central

    Zhao, Meixia; Riegl, Bernhard; Yu, Kefu; Shi, Qi; Zhang, Qiaomin; Liu, Guohui; Yang, Hongqiang; Yan, Hongqiang

    2016-01-01

    Population models are important for resource management and can inform about potential trajectories useful for planning purposes, even with incomplete monitoring data. From size frequency data on Luhuitou fringing reef, Hainan, South China Sea, a matrix population model of massive corals (Porites lutea) was developed and trajectories over 100 years under no disturbance and random disturbances were projected. The model reflects a largely open population of Porites lutea, with low local recruitment and preponderance of imported recruitment. Under no further disturbance, the population of Porites lutea will grow and its size structure will change from predominance of small size classes to large size classes. Therewith, total Porites cover will increase. Even under random disturbances every 10 to 20 years, the Porites population could remain viable, albeit at lower space cover. The models suggest recovery at Luhuitou following the removal of chronic anthropogenic disturbance. Extending the area of coral reef reserves to protect the open coral community and the path of connectivity is advisable and imperative for the conservation of Hainan’s coral reefs. PMID:27622504

  18. Model suggests potential for Porites coral population recovery after removal of anthropogenic disturbance (Luhuitou, Hainan, South China Sea)

    NASA Astrophysics Data System (ADS)

    Zhao, Meixia; Riegl, Bernhard; Yu, Kefu; Shi, Qi; Zhang, Qiaomin; Liu, Guohui; Yang, Hongqiang; Yan, Hongqiang

    2016-09-01

    Population models are important for resource management and can inform about potential trajectories useful for planning purposes, even with incomplete monitoring data. From size frequency data on Luhuitou fringing reef, Hainan, South China Sea, a matrix population model of massive corals (Porites lutea) was developed and trajectories over 100 years under no disturbance and random disturbances were projected. The model reflects a largely open population of Porites lutea, with low local recruitment and preponderance of imported recruitment. Under no further disturbance, the population of Porites lutea will grow and its size structure will change from predominance of small size classes to large size classes. Therewith, total Porites cover will increase. Even under random disturbances every 10 to 20 years, the Porites population could remain viable, albeit at lower space cover. The models suggest recovery at Luhuitou following the removal of chronic anthropogenic disturbance. Extending the area of coral reef reserves to protect the open coral community and the path of connectivity is advisable and imperative for the conservation of Hainan’s coral reefs.

  19. Surviving Coral Bleaching Events: Porites Growth Anomalies on the Great Barrier Reef

    PubMed Central

    Cantin, Neal E.; Lough, Janice M.

    2014-01-01

    Mass coral bleaching affected large parts of the Great Barrier Reef (GBR) in 1998 and 2002. In this study, we assessed if signatures of these major thermal stress events were recorded in the growth characteristics of massive Porites colonies. In 2005 a suite of short (<50 cm) cores were collected from apparently healthy, surviving Porites colonies, from reefs in the central GBR (18–19°S) that have documented observations of widespread bleaching. Sites included inshore (Nelly Bay, Pandora Reef), annually affected by freshwater flood events, midshelf (Rib Reef), only occasionally affected by freshwater floods and offshore (Myrmidon Reef) locations primarily exposed to open ocean conditions. Annual growth characteristics (extension, density and calcification) were measured in 144 cores from 79 coral colonies and analysed over the common 24-year period, 1980–2003. Visual examination of the annual density bands revealed growth hiatuses associated with the bleaching years in the form of abrupt decreases in annual linear extension rates, high density stress bands and partial mortality. The 1998 mass-bleaching event reduced Porites calcification by 13 and 18% on the two inshore locations for 4 years, followed by recovery to baseline calcification rates in 2002. Evidence of partial mortality was apparent in 10% of the offshore colonies in 2002; however no significant effects of the bleaching events were evident in the calcification rates at the mid shelf and offshore sites. These results highlight the spatial variation of mass bleaching events and that all reef locations within the GBR were not equally stressed by the 1998 and 2002 mass bleaching events, as some models tend to suggest, which enabled recovery of calcification on the GBR within 4 years. The dynamics in annual calcification rates and recovery displayed here should be used to improve model outputs that project how coral calcification will respond to ongoing warming of the tropical oceans. PMID:24586377

  20. Surviving coral bleaching events: porites growth anomalies on the Great Barrier Reef.

    PubMed

    Cantin, Neal E; Lough, Janice M

    2014-01-01

    Mass coral bleaching affected large parts of the Great Barrier Reef (GBR) in 1998 and 2002. In this study, we assessed if signatures of these major thermal stress events were recorded in the growth characteristics of massive Porites colonies. In 2005 a suite of short (<50 cm) cores were collected from apparently healthy, surviving Porites colonies, from reefs in the central GBR (18-19°S) that have documented observations of widespread bleaching. Sites included inshore (Nelly Bay, Pandora Reef), annually affected by freshwater flood events, midshelf (Rib Reef), only occasionally affected by freshwater floods and offshore (Myrmidon Reef) locations primarily exposed to open ocean conditions. Annual growth characteristics (extension, density and calcification) were measured in 144 cores from 79 coral colonies and analysed over the common 24-year period, 1980-2003. Visual examination of the annual density bands revealed growth hiatuses associated with the bleaching years in the form of abrupt decreases in annual linear extension rates, high density stress bands and partial mortality. The 1998 mass-bleaching event reduced Porites calcification by 13 and 18% on the two inshore locations for 4 years, followed by recovery to baseline calcification rates in 2002. Evidence of partial mortality was apparent in 10% of the offshore colonies in 2002; however no significant effects of the bleaching events were evident in the calcification rates at the mid shelf and offshore sites. These results highlight the spatial variation of mass bleaching events and that all reef locations within the GBR were not equally stressed by the 1998 and 2002 mass bleaching events, as some models tend to suggest, which enabled recovery of calcification on the GBR within 4 years. The dynamics in annual calcification rates and recovery displayed here should be used to improve model outputs that project how coral calcification will respond to ongoing warming of the tropical oceans.

  1. Influence of Land Development on Holocene Porites Coral Calcification at Nagura Bay, Ishigaki Island, Japan

    PubMed Central

    Sowa, Kohki; Watanabe, Tsuyoshi; Kan, Hironobu; Yamano, Hiroya

    2014-01-01

    To evaluate the relationships between coral calcification, thermal stress, and sedimentation and eutrophication linked to human impact (hereafter referred to as “land development”) by river discharge, we analyzed growth characteristics in the context of a paleoenvironment that was reconstructed from geochemical signals in modern and fossil (1.2 cal kyr BP and 3.5 cal kyr BP, respectively) massive Porites corals from Nagura Bay (“Nagura”) and from modern Porites corals from the estuary of the Todoroki River, Shiraho Reef (“Todoroki”). Both sites are on Ishigaki Island, Japan, and Nagura is located approximately 12 km west of Todoroki. At Nagura, the individual corals provide time windows of 13 (modern), 10 (1.2 cal kyr BP), and 38 yr in length (3.5 cal kyr BP). Here, we present the coral annual calcification for Nagura and Todoroki, and (bi) monthly resolved records of Sr/Ca (a proxy of sea surface temperature (SST)) and Ba/Ca (a proxy of sedimentation and nutrients related to land development) for Nagura. At Nagura, the winter SST was cooler by 2.8°C in the 1.2 cal kyr BP, and the annual and winter SSTs in the 3.5 cal kyr BP were cooler by 2.6°C and 4.6°C, respectively. The annual periodicity of Ba/Ca in modern coral is linked to river discharge and is associated with land development including sugar cane cultivation. Modern coral calcification also has declined with SST warming and increasing Ba/Ca peaks in winter. However, calcification of fossil corals does not appear to have been influenced by variations in Sr/Ca and Ba/Ca. Modern coral growth characteristics at Nagura and Todoroki indicate that coral growth is both spatially and temporally influenced by river discharge and land development. At Nagura, our findings suggest that land development induces negative thermal sensitivity for calcification in winter due to sugar cane harvest, which is a specifically modern phenomenon. PMID:24586393

  2. Simulation of the effects of Acanthaster planci on the population structure of massive corals in the genus Porites: evidence of population resilience?

    NASA Astrophysics Data System (ADS)

    Done, Terence J.

    1987-10-01

    Scleractinian corals in the genus Porites are slow growing, can live for centuries, and can attain great size. In these respects they differ from the majority of coral species, which grow faster and live for years to decades. The predatory starfish Acanthaster planci L. feeds on a wide range of coral species including Porites spp., and during outbreaks in its populations, causes high coral mortality and injury over much of the affected reefs. Because they are slow growing and because recent outbreaks of the starfish occurred only 15 years apart, it may be argued that the Porites populations on affected reefs will be sent into a period of prolonged decline. The present study uses a size stage model of the transition matrix type to predict effects of starfish outbreaks of various frequencies on Porites populations. A transition matrix characterizing the mortality and injury caused in different Porites size classes at John Brewer Reef during an “outbreak” year was determined from field data. Transition matrices for “non-outbreak” years were constructed on the basis of realistic growth rates and postulated survivorship and recruitment schedules. The medium term (˜100 years) effects of outbreaks were simulated by alternation of a single iteration of the outbreak matrix with many iterations of each non-outbreak matrix. By varying the interval between simulated outbreaks it was possible to define combinations of growth rate, survivorship and recruitment which were viable for various outbreak intervals. Simulations based on estimates of the initial size frequency distribution, recruitment rates and colony growth rates for the John Brewer Reef population predicted that the population would remain viable in the face of outbreaks every 15 years only if juvenile and adult survivorship were high. However, within the range of colony growth rates known to occur throughout the Great Barrier Reef and at recruitment rates of the same order as those estimated in the field

  3. The cumulative impact of annual coral bleaching can turn some coral species winners into losers.

    PubMed

    Grottoli, Andréa G; Warner, Mark E; Levas, Stephen J; Aschaffenburg, Matthew D; Schoepf, Verena; McGinley, Michael; Baumann, Justin; Matsui, Yohei

    2014-12-01

    Mass coral bleaching events caused by elevated seawater temperatures result in extensive coral loss throughout the tropics, and are projected to increase in frequency and severity. If bleaching becomes an annual event later in this century, more than 90% of coral reefs worldwide may be at risk of long-term degradation. While corals can recover from single isolated bleaching and can acclimate to recurring bleaching events that are separated by multiple years, it is currently unknown if and how they will survive and possibly acclimatize to annual coral bleaching. Here, we demonstrate for the first time that annual coral bleaching can dramatically alter thermal tolerance in Caribbean corals. We found that high coral energy reserves and changes in the dominant algal endosymbiont type (Symbiodinium spp.) facilitated rapid acclimation in Porites divaricata, whereas low energy reserves and a lack of algal phenotypic plasticity significantly increased susceptibility in Porites astreoides to bleaching the following year. Phenotypic plasticity in the dominant endosymbiont type of Orbicella faveolata did not prevent repeat bleaching, but may have facilitated rapid recovery. Thus, coral holobiont response to an isolated single bleaching event is not an accurate predictor of its response to bleaching the following year. Rather, the cumulative impact of annual coral bleaching can turn some coral species 'winners' into 'losers', and can also facilitate acclimation and turn some coral species 'losers' into 'winners'. Overall, these findings indicate that cumulative impact of annual coral bleaching could result in some species becoming increasingly susceptible to bleaching and face a long-term decline, while phenotypically plastic coral species will acclimatize and persist. Thus, annual coral bleaching and recovery could contribute to the selective loss of coral diversity as well as the overall decline of coral reefs in the Caribbean.

  4. Depth-Independent Reproduction in the Reef Coral Porites astreoides from Shallow to Mesophotic Zones

    PubMed Central

    Holstein, Daniel M.; Smith, Tyler B.; Paris, Claire B.

    2016-01-01

    Mesophotic coral ecosystems between 30–150 m may be important refugia habitat for coral reefs and associated benthic communities from climate change and coastal development. However, reduced light at mesophotic depths may present an energetic challenge to the successful reproduction of light-dependent coral organisms, and limit this refugia potential. Here, the relationship of depth and fecundity was investigated in a brooding depth-generalist scleractinian coral, Porites astreoides from 5–37 m in the U.S. Virgin Islands (USVI) using paraffin tissue histology. Despite a trend of increasing planulae production with depth, no significant differences were found in mean peak planulae density between shallow, mid-depth and mesophotic sites. Differential planulae production over depth is thus controlled by P. astreoides coral cover, which peaks at 10 m and ~35 m in the USVI. These results suggest that mesophotic ecosystems are reproductive refuge for P. astreoides in the USVI, and may behave as refugia for P. astreoides metapopulations providing that vertical larval exchanges are viable. PMID:26789408

  5. Diversity and distribution of Actinobacteria associated with reef coral Porites lutea.

    PubMed

    Kuang, Weiqi; Li, Jie; Zhang, Si; Long, Lijuan

    2015-01-01

    Actinobacteria is a ubiquitous major group in coral holobiont. The diversity and spatial and temporal distribution of actinobacteria have been rarely documented. In this study, diversity of actinobacteria associated with mucus, tissue and skeleton of Porites lutea and in the surrounding seawater were examined every 3 months for 1 year on Luhuitou fringing reef. The population structures of the P. lutea-associated actinobacteria were analyzed using phylogenetic analysis of 16S rRNA gene clone libraries, which demonstrated highly diverse actinobacteria profiles in P. lutea. A total of 25 described families and 10 unnamed families were determined in the populations, and 12 genera were firstly detected in corals. The Actinobacteria diversity was significantly different between the P. lutea and the surrounding seawater. Only 10 OTUs were shared by the seawater and coral samples. Redundancy and hierarchical cluster analyses were performed to analyze the correlation between the variations of actinobacteria population within the divergent compartments of P. lutea, seasonal changes, and environmental factors. The actinobacteria communities in the same coral compartment tended to cluster together. Even so, an extremely small fraction of OTUs was common in all three P. lutea compartments. Analysis of the relationship between actinobacteria assemblages and the environmental parameters showed that several genera were closely related to specific environmental factors. This study highlights that coral-associated actinobacteria populations are highly diverse, and spatially structured within P. lutea, and they are distinct from which in the ambient seawater.

  6. Diversity and distribution of Actinobacteria associated with reef coral Porites lutea

    PubMed Central

    Kuang, Weiqi; Li, Jie; Zhang, Si; Long, Lijuan

    2015-01-01

    Actinobacteria is a ubiquitous major group in coral holobiont. The diversity and spatial and temporal distribution of actinobacteria have been rarely documented. In this study, diversity of actinobacteria associated with mucus, tissue and skeleton of Porites lutea and in the surrounding seawater were examined every 3 months for 1 year on Luhuitou fringing reef. The population structures of the P. lutea-associated actinobacteria were analyzed using phylogenetic analysis of 16S rRNA gene clone libraries, which demonstrated highly diverse actinobacteria profiles in P. lutea. A total of 25 described families and 10 unnamed families were determined in the populations, and 12 genera were firstly detected in corals. The Actinobacteria diversity was significantly different between the P. lutea and the surrounding seawater. Only 10 OTUs were shared by the seawater and coral samples. Redundancy and hierarchical cluster analyses were performed to analyze the correlation between the variations of actinobacteria population within the divergent compartments of P. lutea, seasonal changes, and environmental factors. The actinobacteria communities in the same coral compartment tended to cluster together. Even so, an extremely small fraction of OTUs was common in all three P. lutea compartments. Analysis of the relationship between actinobacteria assemblages and the environmental parameters showed that several genera were closely related to specific environmental factors. This study highlights that coral-associated actinobacteria populations are highly diverse, and spatially structured within P. lutea, and they are distinct from which in the ambient seawater. PMID:26539166

  7. Depth-Independent Reproduction in the Reef Coral Porites astreoides from Shallow to Mesophotic Zones.

    PubMed

    Holstein, Daniel M; Smith, Tyler B; Paris, Claire B

    2016-01-01

    Mesophotic coral ecosystems between 30-150 m may be important refugia habitat for coral reefs and associated benthic communities from climate change and coastal development. However, reduced light at mesophotic depths may present an energetic challenge to the successful reproduction of light-dependent coral organisms, and limit this refugia potential. Here, the relationship of depth and fecundity was investigated in a brooding depth-generalist scleractinian coral, Porites astreoides from 5-37 m in the U.S. Virgin Islands (USVI) using paraffin tissue histology. Despite a trend of increasing planulae production with depth, no significant differences were found in mean peak planulae density between shallow, mid-depth and mesophotic sites. Differential planulae production over depth is thus controlled by P. astreoides coral cover, which peaks at 10 m and ~35 m in the USVI. These results suggest that mesophotic ecosystems are reproductive refuge for P. astreoides in the USVI, and may behave as refugia for P. astreoides metapopulations providing that vertical larval exchanges are viable.

  8. Stable mucus-associated bacterial communities in bleached and healthy corals of Porites lobata from the Arabian Seas.

    PubMed

    Hadaidi, Ghaida; Röthig, Till; Yum, Lauren K; Ziegler, Maren; Arif, Chatchanit; Roder, Cornelia; Burt, John; Voolstra, Christian R

    2017-03-31

    Coral reefs are subject to coral bleaching manifested by the loss of endosymbiotic algae from coral host tissue. Besides algae, corals associate with bacteria. In particular, bacteria residing in the surface mucus layer are thought to mediate coral health, but their role in coral bleaching is unknown. We collected mucus from bleached and healthy Porites lobata colonies in the Persian/Arabian Gulf (PAG) and the Red Sea (RS) to investigate bacterial microbiome composition using 16S rRNA gene amplicon sequencing. We found that bacterial community structure was notably similar in bleached and healthy corals, and the most abundant bacterial taxa were identical. However, fine-scale differences in bacterial community composition between the PAG and RS were present and aligned with predicted differences in sulfur- and nitrogen-cycling processes. Based on our data, we argue that bleached corals benefit from the stable composition of mucus bacteria that resemble their healthy coral counterparts and presumably provide a conserved suite of protective functions, but monitoring of post-bleaching survival is needed to further confirm this assumption. Conversely, fine-scale site-specific differences highlight flexibility of the bacterial microbiome that may underlie adjustment to local environmental conditions and contribute to the widespread success of Porites lobata.

  9. Stable mucus-associated bacterial communities in bleached and healthy corals of Porites lobata from the Arabian Seas

    PubMed Central

    Hadaidi, Ghaida; Röthig, Till; Yum, Lauren K.; Ziegler, Maren; Arif, Chatchanit; Roder, Cornelia; Burt, John; Voolstra, Christian R.

    2017-01-01

    Coral reefs are subject to coral bleaching manifested by the loss of endosymbiotic algae from coral host tissue. Besides algae, corals associate with bacteria. In particular, bacteria residing in the surface mucus layer are thought to mediate coral health, but their role in coral bleaching is unknown. We collected mucus from bleached and healthy Porites lobata colonies in the Persian/Arabian Gulf (PAG) and the Red Sea (RS) to investigate bacterial microbiome composition using 16S rRNA gene amplicon sequencing. We found that bacterial community structure was notably similar in bleached and healthy corals, and the most abundant bacterial taxa were identical. However, fine-scale differences in bacterial community composition between the PAG and RS were present and aligned with predicted differences in sulfur- and nitrogen-cycling processes. Based on our data, we argue that bleached corals benefit from the stable composition of mucus bacteria that resemble their healthy coral counterparts and presumably provide a conserved suite of protective functions, but monitoring of post-bleaching survival is needed to further confirm this assumption. Conversely, fine-scale site-specific differences highlight flexibility of the bacterial microbiome that may underlie adjustment to local environmental conditions and contribute to the widespread success of Porites lobata. PMID:28361923

  10. Induction of Larval Settlement in the Reef Coral Porites astreoides by a Cultivated Marine Roseobacter Strain.

    PubMed

    Sharp, K H; Sneed, J M; Ritchie, K B; Mcdaniel, L; Paul, V J

    2015-04-01

    Successful larval settlement and recruitment by corals is critical for the survival of coral reef ecosystems. Several closely related strains of γ-proteobacteria have been identified as cues for coral larval settlement, but the inductive properties of other bacterial taxa naturally occurring in reef ecosystems have not yet been explored. In this study, we assayed bacterial strains representing taxonomic groups consistently detected in corals for their ability to influence larval settlement in the coral Porites astreoides. We identified one α-proteobacterial strain, Roseivivax sp. 46E8, which significantly increased larval settlement in P. astreoides. Logarithmic growth phase (log phase) cell cultures of Roseivivax sp. 46E8 and filtrates (0.22μm) from log phase Roseivivax sp. 46E8 cultures significantly increased settlement, suggesting that an extracellular settlement factor is produced during active growth phase. Filtrates from log phase cultures of two other bacterial isolates, Marinobacter sp. 46E3, and Cytophaga sp. 46B6, also significantly increased settlement, but the cell cultures themselves did not. Monospecific biofilms of the three strains did not result in significant increases in larval settlement. Organic and aqueous/methanol extracts of Roseivivax sp. 46E8 cultures did not affect larval settlement. Examination of filtrates from cell cultures showed that Roseivivax sp. 46E8 spontaneously generated virus-like particles in log and stationary phase growth. Though the mechanism of settlement enhancement by Roseivivax sp. 46E8 is not yet elucidated, our findings point to a new aspect of coral-Roseobacter interactions that should be further investigated, especially in naturally occurring, complex microbial biofilms on reef surfaces.

  11. Vibrational spectroscopic characterization of growth bands in Porites coral from South China Sea

    NASA Astrophysics Data System (ADS)

    Song, Yinxian; Yu, Kefu; Ayoko, Godwin A.; Frost, Ray L.; Shi, Qi; Feng, Yuexing; Zhao, Jianxin

    2013-08-01

    A series of samples from different growth bands of Porites coral skeleton were studied using Raman, infrared reflectance methods. The Raman spectra proved that skeleton samples from different growth bands have the same mineral phase as aragonite, but a band at 133 cm-1 for the top layer shows a transition from ˜120 cm-1 for vaterite to ˜141 cm-1 for aragonite. It is inferred that the vaterite should be the precursor of aragonite of coral skeleton. The positional shift in the infrared spectra of the skeleton samples from growth bands correlate significantly to their minor elements (Li, Mg, Sr, Mn, Fe and U) contents. Mg, Sr and U especially have significant negative correlations with the positions of the antisymmetric stretching band ν3 at ˜1469 cm-1. And Li shows a high negative correlation with ν2 band (˜855 cm-1), while Sr and Mn show similar negative correlation with ν4 band (˜712 cm-1). And Mn also shows a negative correlation with ν1 band (˜1082 cm-1). A significantly negative correlation is observed for U with ν1 + ν4 band (˜1786 cm-1). However, Fe shows positive correlation with ν1, ν2, ν3, ν4 and ν1 + ν4 bands shifts, especially a significant correlation with ν1 band (˜1082 cm-1). New insights into the characteristics of coral at different growth bands of skeleton are given in present work.

  12. Diversity and dynamics of bacterial communities in early life stages of the Caribbean coral Porites astreoides

    PubMed Central

    Sharp, Koty H; Distel, Dan; Paul, Valerie J

    2012-01-01

    In this study, we examine microbial communities of early developmental stages of the coral Porites astreoides by sequence analysis of cloned 16S rRNA genes, terminal restriction fragment length polymorphism (TRFLP), and fluorescence in situ hybridization (FISH) imaging. Bacteria are associated with the ectoderm layer in newly released planula larvae, in 4-day-old planulae, and on the newly forming mesenteries surrounding developing septa in juvenile polyps after settlement. Roseobacter clade-associated (RCA) bacteria and Marinobacter sp. are consistently detected in specimens of P. astreoides spanning three early developmental stages, two locations in the Caribbean and 3 years of collection. Multi-response permutation procedures analysis on the TRFLP results do not support significant variation in the bacterial communities associated with P. astreoides larvae across collection location, collection year or developmental stage. The results are the first evidence of vertical transmission (from parent to offspring) of bacteria in corals. The results also show that at least two groups of bacterial taxa, the RCA bacteria and Marinobacter, are consistently associated with juvenile P. astreoides against a complex background of microbial associations, indicating that some components of the microbial community are long-term associates of the corals and may impact host health and survival. PMID:22113375

  13. Diversity and dynamics of bacterial communities in early life stages of the Caribbean coral Porites astreoides.

    PubMed

    Sharp, Koty H; Distel, Dan; Paul, Valerie J

    2012-04-01

    In this study, we examine microbial communities of early developmental stages of the coral Porites astreoides by sequence analysis of cloned 16S rRNA genes, terminal restriction fragment length polymorphism (TRFLP), and fluorescence in situ hybridization (FISH) imaging. Bacteria are associated with the ectoderm layer in newly released planula larvae, in 4-day-old planulae, and on the newly forming mesenteries surrounding developing septa in juvenile polyps after settlement. Roseobacter clade-associated (RCA) bacteria and Marinobacter sp. are consistently detected in specimens of P. astreoides spanning three early developmental stages, two locations in the Caribbean and 3 years of collection. Multi-response permutation procedures analysis on the TRFLP results do not support significant variation in the bacterial communities associated with P. astreoides larvae across collection location, collection year or developmental stage. The results are the first evidence of vertical transmission (from parent to offspring) of bacteria in corals. The results also show that at least two groups of bacterial taxa, the RCA bacteria and Marinobacter, are consistently associated with juvenile P. astreoides against a complex background of microbial associations, indicating that some components of the microbial community are long-term associates of the corals and may impact host health and survival.

  14. Combining geochemical proxies in Porites coral cores from Chuuk Lagoon, Micronesia

    NASA Astrophysics Data System (ADS)

    Wagner, A. J.; Zivkovic, J.; Anderson, D.; Umling, N. E.

    2013-12-01

    Chuuk Lagoon (7°N, 152°E), part of the Federated States of Micronesia, is centrally located in the Western Pacific Warm Pool (WPWP) and provides an ideal location for studies of El Niño - Southern Oscillation (ENSO) and Warm Pool processes. The WPWP is a key aspect of the global climate, exchanging heat and carbon with the atmosphere as well as with the surrounding ocean and the underlying water masses. Recent work has indicated long-term changes in the WPWP, including freshening and warming, that have been attributed to climate change. This region also experiences large fluctuations in precipitation and temperature due to interannual oscillations in ENSO. Oxygen isotope (δ18O) data from corals provides insight into the isotopic ratio of the water in which the corals grew their aragonitic skeletons. However, the oxygen isotope ratio of seawater varies with both changes in temperature and salinity. Sr/Ca ratios vary with seawater temperature and, when combined with δ18O, can be used to interpret both temperature and salinity variations. Three coral cores from large Porites lobata coral heads were collected from Chuuk Lagoon in June 2011, and one additional core was collected in 2008. Two cores (one in 2008 and another in 2011) were collected near the main island within the lagoon where they are subject to large precipitation and temperature variability due to fluctuations in ENSO. The remaining two cores were collected at the outer edge of the atoll, just inside of the barrier reef. These cores were collected in less than 3 m of water and were constantly being flushed with water from the open ocean warm pool. Seasonal variability in temperature and salinity are expected to be very low at this site. Stable isotope (δ18O, δ13C) and trace element (Sr/Ca) analyses for the upper portion of these cores will be presented and compared to ENSO variability and observed trends in the WPWP. An adjacent lagoon coral is valuable in developing the lagoon history, while the

  15. Sex-associated variations in coral skeletal oxygen and carbon isotopic composition of Porites panamensis in the southern Gulf of California

    NASA Astrophysics Data System (ADS)

    Cabral-Tena, Rafael A.; Sánchez, Alberto; Reyes-Bonilla, Héctor; Ruvalcaba-Díaz, Angel H.; Balart, Eduardo F.

    2016-05-01

    variables; therefore, variations in skeletal δ13C appear to be driven mainly by metabolic effects. Our results support the hypothesis of a sex-associated difference in skeletal δ18O and δ13C signal, and suggest that environmental conditions and coral growth parameters affect skeletal isotopic signals differently in each sex. Although these findings relate to one gonochoric brooding species, they may have some implications for the more commonly used gonochoric spawning species such as Porites lutea and Porites lobata.

  16. Long distance dispersal and vertical gene flow in the Caribbean brooding coral Porites astreoides

    PubMed Central

    Serrano, Xaymara M.; Baums, Iliana B.; Smith, Tyler B.; Jones, Ross J.; Shearer, Tonya L.; Baker, Andrew C.

    2016-01-01

    To date, most assessments of coral connectivity have emphasized long-distance horizontal dispersal of propagules from one shallow reef to another. The extent of vertical connectivity, however, remains largely understudied. Here, we used newly-developed and existing DNA microsatellite loci for the brooding coral Porites astreoides to assess patterns of horizontal and vertical connectivity in 590 colonies collected from three depth zones (≤10 m, 15–20 m and ≥25 m) at sites in Florida, Bermuda and the U.S. Virgin Islands (USVI). We also tested whether maternal transmission of algal symbionts (Symbiodinium spp.) might limit effective vertical connectivity. Overall, shallow P. astreoides exhibited high gene flow between Florida and USVI, but limited gene flow between these locations and Bermuda. In contrast, there was significant genetic differentiation by depth in Florida (Upper Keys, Lower Keys and Dry Tortugas), but not in Bermuda or USVI, despite strong patterns of depth zonation in algal symbionts at two of these locations. Together, these findings suggest that P. astreoides is effective at dispersing both horizontally and vertically despite its brooding reproductive mode and maternal transmission of algal symbionts. In addition, these findings might help explain the ecological success reported for P. astreoides in the Caribbean in recent decades. PMID:26899614

  17. Macrobioerosion in Porites corals in subtropical northern South China Sea: a limiting factor for high-latitude reef framework development

    NASA Astrophysics Data System (ADS)

    Chen, Tianran; Li, Shu; Yu, Kefu

    2013-03-01

    Bioerosion is an important limiting factor in carbonate accretion and reef framework development; however, few studies have quantified the direct impact of macroborers on high-latitude coral communities, which are viewed as potential refuge during a period of global warming. In this study, internal macrobioerosion of Porites corals was examined at Daya Bay, subtropical northern South China Sea. The principal borers were the bivalve Lithophaga spp. and the sponges Cliona spp. and Cliothosa spp. (≥80 %), while sipunculid and polychaete worms and barnacles accounted for small amounts of bioerosion (≤20 %). Porites corals were heavily bioeroded in areas impacted by aquacultural and urban activities (10.34-27.55 %) compared with corals in relatively unpolluted areas (2.18-6.76 %). High levels of bioerosion, especially boring bivalve infestation, significantly weaken the corals and increase their susceptibility to dislodgement and fragmentation in typhoons, limiting accumulation of limestone framework. This study implies that carbonate accretion and reef development for high-latitude coral communities may be limited in future high-CO2 and eutrophication-stressed environments.

  18. Lithium content of the aragonitic skeletons of massive Porites corals: a new tool to reconstruct tropical sea surface temperatures?

    NASA Astrophysics Data System (ADS)

    Hathorne, E.; Felis, T.; Suzuki, A.; Kawahata, H.

    2009-12-01

    Knowledge of the variability of tropical sea surface temperature (SST) on seasonal and inter-annual timescales is essential to our understanding of important climatic systems like ENSO. The centimeter scale annual growth bands of the aragonitic skeletons of massive Porites corals provide a unique opportunity to extend the dataset of tropical SST beyond the brief instrumental record. The strontium content of coral aragonite, usually expressed as the Sr/Ca ratio, has proven to be a robust indicator of the seawater temperature in which the coral grew. However, concerns about variations in seawater Sr/Ca on glacial to interglacial timescales and the potential impact of early marine diagenesis make additional geochemical SST proxies desirable. Lithium is a good candidate because, like Sr and Ca, it has a long oceanic residence time but the global Li geochemical cycle has distinctive sources and sinks from that of Sr. Therefore, changes in seawater Sr/Ca resulting from eustatic sea level changes are unlikely to be accompanied by changes in seawater Li/Ca. Prompted by this and a pioneering study by Marriott and others [1] which demonstrated a negative temperature dependence for the Li/Ca of Porites aragonite of ~4 % per °C, we have conducted a calibration study of coral Li/Ca. We measured Li/Ca ratios at a bimonthly resolution in a modern Porites coral from the subtropical north western Pacific where the average annual SST range is 7 °C [2]. This large temperature range Porites coral has previously been used to successfully calibrate both Sr/Ca and U/Ca SST proxies [2] and we also find clear annual cycles in coral Li/Ca for the entire twenty year study period. The relationship between coral Li/Ca and local SST is good with Li/Ca decreasing by ~1.5 % with every °C increase of SST. This compares well with the equivalent changes in Sr/Ca (0.5%) and U/Ca (3%) and indicates coral Li/Ca could be a very useful tool for reconstructing tropical SST. [1] Marriott et al. (2004

  19. Evaluating 20th century warming trends with modern Porites corals from the western Indian Ocean

    NASA Astrophysics Data System (ADS)

    Pfeiffer, M.; Zinke, J.; Dullo, W.-C.; Cahyarini, S. Y.

    2009-04-01

    Recent studies suggest that instrumental records of sea surface temperature (SST) are unreliable prior to 1965 due to changes in the measurement procedures. Thompson et al. (2008) identified an artificial cool bias of up to 0.3˚ C in global mean SSTs between 1945 and the mid-1960s. Geochemical parameters in skeletons of massive corals can be used to infer past changes in climate on seasonal to centennial time scales. The Sr/Ca ratio of coral aragonite is a widely used tool for deriving high-resolution proxy records of past sea surface temperatures. Application of the Sr/Ca paleothermometer relies on the assumption that coral Sr/Ca varies predictably with temperature and that seawater Sr/Ca is invariant on millennial timescales due to the long residence time of Sr and Ca in the ocean. In contrast, the oxygen isotope ratios (^18O) of coral aragonite vary in response to temperature and changes in the ^18O of seawater, the latter depending on the freshwater balance. Thus, coral ^18O may be used as a record of past sea surface temperatures only at sites were ^18O seawater variations are negligible. SST in the western tropical Indian Ocean closely follows global mean temperature trends (Funk et al., 2008). Here we present a set of Porites coral Sr/Ca and/or oxygen isotope records from the tropical Indian Ocean covering the past 120-336 years (Seychelles, Chagos Archipelago). We computed a composite sea surface temperature record for the Western Indian Ocean using ^18O (Seychelles) and Sr/Ca (Chagos). This record clearly follows instrumental SST trends in the Western tropical Indian Ocean, except in the 1945-1965 interval, were instrumental SST data show a pronounced cooling not evident in the coral proxy index (the linear correlation coefficient between the coral index and instrumental SST is r=0.86 if we omit the most problematic time period from 1945 to 1960). However, the coral index follows the global land surface air temperature trend, which is free of systematic

  20. Gene expression under chronic heat stress in populations of the mustard hill coral (Porites astreoides) from different thermal environments.

    PubMed

    Kenkel, C D; Meyer, E; Matz, M V

    2013-08-01

    Recent evidence suggests that corals can acclimatize or adapt to local stress factors through differential regulation of their gene expression. Profiling gene expression in corals from diverse environments can elucidate the physiological processes that may be responsible for maximizing coral fitness in their natural habitat and lead to a better understanding of the coral's capacity to survive the effects of global climate change. In an accompanying paper, we show that Porites astreoides from thermally different reef habitats exhibit distinct physiological responses when exposed to 6 weeks of chronic temperature stress in a common garden experiment. Here, we describe expression profiles obtained from the same corals for a panel of 9 previously reported and 10 novel candidate stress response genes identified in a pilot RNA-Seq experiment. The strongest expression change was observed in a novel candidate gene potentially involved in calcification, SLC26, a member of the solute carrier family 26 anion exchangers, which was down-regulated by 92-fold in bleached corals relative to controls. The most notable signature of divergence between coral populations was constitutive up-regulation of metabolic genes in corals from the warmer inshore location, including the gluconeogenesis enzymes pyruvate carboxylase and phosphoenolpyruvate carboxykinase and the lipid beta-oxidation enzyme acyl-CoA dehydrogenase. Our observations highlight several molecular pathways that were not previously implicated in the coral stress response and suggest that host management of energy budgets might play an adaptive role in holobiont thermotolerance.

  1. Coral hybridization or phenotypic variation? Genomic data reveal gene flow between Porites lobata and P. Compressa.

    PubMed

    Forsman, Z H; Knapp, I S S; Tisthammer, K; Eaton, D A R; Belcaid, M; Toonen, R J

    2017-03-31

    Major gaps remain in our understanding of the ecology, evolution, biodiversity, biogeography, extinction risk, and adaptive potential of reef building corals. One of the central challenges remains that there are few informative genetic markers for studying boundaries between species, and variation within species. Reduced representation sequencing approaches, such as RADseq (Restriction site Associated DNA sequencing) have great potential for resolving such relationships. However, it is necessary to identify loci in order to make inferences for endosymbiotic organisms such as corals. Here, we examined twenty-one coral holobiont ezRAD libraries from Hawai'i, focusing on P. lobata and P. compressa, two species with contrasting morphology and habitat preference that previous studies have not resolved. We used a combination of de novo assembly and reference mapping approaches to identify and compare loci: we used reference mapping to extract and compare nearly complete mitochondrial genomes, ribosomal arrays, and histone genes. We used de novo clustering and phylogenomic methods to compare the complete holobiont data set with coral and symbiont subsets that map to transcriptomic data. In addition, we used reference assemblies to examine genetic structure from SNPs (Single Nucleotide Polymorphisms). All approaches resolved outgroup taxa but failed to resolve P. lobata and P. compressa as distinct, with mito-nuclear discordance and shared mitochondrial haplotypes within the species complex. The holobiont and 'coral transcriptomic' datasets were highly concordant, revealing stronger genetic structure between sites than between coral morphospecies. These results suggest that either branching morphology is a polymorphic trait, or that these species frequently hybridize. This study provides examples of several approaches to acquire, identify, and compare loci across metagenomic samples such as the coral holobiont while providing insights into the nature of coral variability.

  2. Effects of UV radiation on the growth, photosynthetic and photoprotective components, and reproduction of the Caribbean shallow-water coral Porites furcata

    NASA Astrophysics Data System (ADS)

    Torres-Pérez, J. L.; Armstrong, R. A.

    2012-12-01

    Shallow reef corals can frequently be subjected to high doses of ultraviolet radiation [280-400 nm (UVR)] and have developed mechanisms to cope with this. Nevertheless, slight changes in this stressor may impact their physiology and ultimately their survival. Here, we present results on the effects of artificially enhanced UVR on the growth, reproduction, production of photosynthetic pigments and photoprotective compounds of the Caribbean shallow-water branching coral Porites furcata. Corals were randomly located in one of the three different treatments: normal photosynthetically active radiation (PAR) + UVR; normal PAR+ enhanced UVR; normal PAR+ depleted UVR. Growth rates were measured using the Alizarin red staining method, photosynthetic pigments as well as mycosporine-like amino acids (MAAs) were quantified through high-performance liquid chromatography, and fecundity was estimated after histological analyses. Growth and photosynthetic pigment concentration were negatively correlated with increased UVR, compared to controls exposed to normal UVR. A significant increase in MAAs was also found in colonies under enhanced UVR. Based on their respective concentrations, the primary mycosporine-glycine (λmax = 310 nm) and shinorine (λmax = 333 nm) are the main contributors to UVR absorption in this species, while the levels of the secondary MAA palythine (λmax = 320 nm) tripled toward the end of the 128 days of the experimental period. While several physical factors may influence reef coral physiology, the results suggest that slight increases in UVR can debilitate the skeletal constitution and severely reduce the fecundity of corals living in shallow waters.

  3. No gene flow across the Eastern Pacific Barrier in the reef-building coral Porites lobata.

    PubMed

    Baums, Iliana B; Boulay, Jennifer N; Polato, Nicholas R; Hellberg, Michael E

    2012-11-01

    The expanse of deep water between the central Pacific islands and the continental shelf of the Eastern Tropical Pacific is regarded as the world's most potent marine biogeographic barrier. During recurrent climatic fluctuations (ENSO, El Niño Southern Oscillation), however, changes in water temperature and the speed and direction of currents become favourable for trans-oceanic dispersal of larvae from central Pacific to marginal eastern Pacific reefs. Here, we investigate the population connectivity of the reef-building coral Porites lobata across the Eastern Pacific Barrier (EPB). Patterns of recent gene flow in samples (n = 1173) from the central Pacific and the Eastern Tropical Pacific (ETP) were analysed with 12 microsatellite loci. Results indicated that P. lobata from the ETP are strongly isolated from those in the central Pacific and Hawaii (F(ct) ' = 0.509; P < 0.001). However, samples from Clipperton Atoll, an oceanic island on the eastern side of the EPB, grouped with the central Pacific. Within the central Pacific, Hawaiian populations were strongly isolated from three co-occurring clusters found throughout the remainder of the central Pacific. No further substructure was evident in the ETP. Changes in oceanographic conditions during ENSO over the past several thousand years thus appear insufficient to support larval deliveries from the central Pacific to the ETP or strong postsettlement selection acts on ETP settlers from the central Pacific. Recovery of P. lobata populations in the frequently disturbed ETP thus must depend on local larval sources.

  4. Heritable differences in fitness-related traits among populations of the mustard hill coral, Porites astreoides

    PubMed Central

    Kenkel, C D; Setta, S P; Matz, M V

    2015-01-01

    A population's potential for rapid evolutionary adaptation can be estimated from the amount of genetic variation in fitness-related traits. Inshore populations of the mustard hill coral (Porites astreoides) have been shown to be more tolerant to thermal stress than offshore populations, but it is unclear whether this difference is due to long-term physiological acclimatization or genetic adaptation. Here, we evaluated variation in growth rate and survival among 38 families of juvenile recruits of P. astreoides spawned by colonies originating from inshore and offshore locations. Recruits were reared in a common garden for 5 weeks and then subjected to two thermal treatments (28  and 31 °C) for 2.5 weeks. The most significant effects were detected during the first 5 weeks, before thermal stress was applied: 27–30% of variance in growth and 94% of variance in recruit survival was attributable to parental effects. Genotyping of eight microsatellite loci indicated that the high early mortality of some of the recruit families was not due to higher inbreeding. Post treatment, parental effects diminished such that only 10–15% of variance in growth rate was explained, which most likely reflects the dissipation of maternal effects. However, offshore-origin recruits still grew significantly less under elevated temperature compared with inshore-origin recruits. These differences observed in naive juvenile corals suggest that population-level variation in fitness in response to different thermal environments has a genetic basis and could represent raw material for natural selection in times of climate change. PMID:26081798

  5. The relationship between the ratio of strontium to calcium and sea-surface temperature in a modern Porites astreoides coral: Implications for using P. astreoides as a paleoclimate archive

    USGS Publications Warehouse

    Tess E. Busch,; Flannery, Jennifer A.; Richey, Julie N.; Stathakopoulos, Anastasios

    2015-11-13

    An inverse relationship has been demonstrated between water temperature and the ratio of strontium to calcium (Sr/Ca) in coral aragonite for a number of Pacific species of the genus Porites. This empirically determined relationship has been used to reconstruct past sea-surface temperature (SST) from modern and Holocene age coral archives. A study was conducted to investigate this relationship for Porites astreoides to determine the potential for using these corals as a paleotemperature archive in the Caribbean and western tropical Atlantic Ocean. Skeletal aragonite from a P. astreoides colony growing offshore of the southeast coast of Florida was subsampled with a mean temporal resolution of 14 samples per year and analyzed for Sr/Ca. The resulting Sr/Ca time series yielded well-defined annual cycles that correspond to annual growth bands in the coral. Sr/Ca was regressed against a monthly SST record from C-MAN buoy station FWYF1 (located at Fowey Rocks, Florida), resulting in the following Sr/Ca-SST relationship: Sr/Ca = –0.040*SST + 10.128 (R = –0.77). A 10-year time series of Sr/Ca-derived SST yields annual cycles with a 10–12 degree Celsius seasonal amplitude, consistent with available local instrumental records. We conclude that Sr/Ca in Porites astreoides from the Caribbean/Atlantic region has high potential for developing subannually resolved modern and recent Holocene SST records.

  6. Development of Gene Expression Markers of Acute Heat-Light Stress in Reef-Building Corals of the Genus Porites

    PubMed Central

    Kenkel, Carly D.; Aglyamova, Galina; Alamaru, Ada; Bhagooli, Ranjeet; Capper, Roxana; Cunning, Ross; deVillers, Amanda; Haslun, Joshua A.; Hédouin, Laetitia; Keshavmurthy, Shashank; Kuehl, Kristin A.; Mahmoud, Huda; McGinty, Elizabeth S.; Montoya-Maya, Phanor H.; Palmer, Caroline V.; Pantile, Raffaella; Sánchez, Juan A.; Schils, Tom; Silverstein, Rachel N.; Squiers, Logan B.; Tang, Pei-Ciao; Goulet, Tamar L.; Matz, Mikhail V.

    2011-01-01

    Coral reefs are declining worldwide due to increased incidence of climate-induced coral bleaching, which will have widespread biodiversity and economic impacts. A simple method to measure the sub-bleaching level of heat-light stress experienced by corals would greatly inform reef management practices by making it possible to assess the distribution of bleaching risks among individual reef sites. Gene expression analysis based on quantitative PCR (qPCR) can be used as a diagnostic tool to determine coral condition in situ. We evaluated the expression of 13 candidate genes during heat-light stress in a common Caribbean coral Porites astreoides, and observed strong and consistent changes in gene expression in two independent experiments. Furthermore, we found that the apparent return to baseline expression levels during a recovery phase was rapid, despite visible signs of colony bleaching. We show that the response to acute heat-light stress in P. astreoides can be monitored by measuring the difference in expression of only two genes: Hsp16 and actin. We demonstrate that this assay discriminates between corals sampled from two field sites experiencing different temperatures. We also show that the assay is applicable to an Indo-Pacific congener, P. lobata, and therefore could potentially be used to diagnose acute heat-light stress on coral reefs worldwide. PMID:22046408

  7. Species composition and morphologic variation of Porites in the Gulf of California

    NASA Astrophysics Data System (ADS)

    López-Pérez, R. A.

    2013-09-01

    Morphometric analysis of corallite calices confirmed that from the late Miocene to the Recent, four species of Porites have inhabited the Gulf of California: the extinct Porites carrizensis, the locally extirpated Porites lobata and the extant Porites sverdrupi and Porites panamensis. Furthermore, large-scale spatial and temporal phenotypic plasticity was observed in the dominant species P. panamensis. Canonical discriminant analysis and ANOVA demonstrated that the calice structures of P. panamensis experienced size reduction between the late Pleistocene and Recent. Similarly, PERMANOVA, regression and correlation analyses demonstrated that across the 800 km north to south in the gulf, P. panamensis populations displayed a similar reduction in calice structures. Based on correlation analysis with environmental data, these large spatial changes are likely related to changes in nutrient concentration and sea surface temperature. As such, the large-scale spatial and temporal phenotypic variation recorded in populations of P. panamensis in the Gulf of California is likely related to optimization of corallite performance (energy acquisition) within various environmental scenarios. These findings may have relevance to modern conservation efforts within this ecological dominant genus.

  8. Impact of skeletal dissolution and secondary aragonite on trace element and isotopic climate proxies in Porites corals

    NASA Astrophysics Data System (ADS)

    Hendy, E. J.; Gagan, M. K.; Lough, J. M.; McCulloch, M.; Demenocal, P. B.

    2007-12-01

    Restricted zones of recent dissolution and secondary aragonite infilling were identified in a coral core collected in 1986 from a living massive Porites colony from the central Great Barrier Reef, Australia. Secondary aragonite needles, ≥20 μm long, cover skeletal surfaces deposited from 1972 to late 1974 and increase bulk density by 10%. Dissolution is observed above this zone, whereas older skeleton is pristine. We investigate the impact of both types of early marine diagenesis on skeletal geochemistry and coral paleoclimate reconstructions by comparison with similar records from eight contemporary Porites colonies collected at nearby reefs. Secondary aragonite overgrowth causes anomalies in skeletal density, Mg/Ca, Sr/Ca, U/Ca, δ18O, and δ13C. The secondary aragonite is consistently associated with a cool temperature anomaly for each of the sea surface temperature (SST) proxies (δ18O-SST -1.6°C; Sr/Ca-SST -1.7°C; Mg/Ca-SST -1.9°C; U/Ca-SST -2.8°C). Dissolution, through incongruent leaching, also causes cool SST artifacts but only for trace element ratios (Mg/Ca-SST -1.2°C; Sr/Ca-SST -1.2°C; U/Ca-SST -2.1°C). The sequence of preference with respect to dissolution of coral skeleton in seawater is Mg > Ca > Sr > U. Rigorous screening of coral material for paleoclimate reconstructions is therefore necessary to detect both dissolution and the presence of secondary minerals. The excellent agreement between apparent SST anomalies generated by different modes of diagenesis means that replication of tracers within a single coral cannot be used to validate climate-proxy interpretations. Poor replication of records between different coral colonies, however, provides a strong indication of nonclimatic artifacts such as dissolution and secondary aragonite.

  9. Effects of Coralliophila violacea on tissue loss in the scleractinian corals Porites spp. depend on host response

    USGS Publications Warehouse

    Raymundo, L.; Work, Thierry M.; Miller, R.L.; Lozada-Misa, P.L.

    2016-01-01

    We investigated interactions between the corallivorous gastropod Coralliophila violacea and its preferred hosts Porites spp. Our objectives were to experimentally determine whether tissue loss could progress in Porites during or after Coralliophila predation on corals with and without tissue loss and to histologically document snail predation. In 64% of feeding scars, tissue regenerated within 3 wk, leaving no trace of predation. However, in roughly 28% of scars, lesions progressed to subacute tissue loss resembling white syndrome. In feeding experiments, scars from snails previously fed diseased tissue developed progressive tissue loss twice as frequently as scars from snails previously fed healthy tissue. Scars from previously healthy-fed snails were 3 times as likely to heal as those from previously diseased-fed snails. Histology revealed marked differences in host responses to snails; P. cylindrica manifested a robust inflammatory response with fewer secondary colonizing organisms such as algae, sponges, and helminths, whereas P. rus showed no evident inflammation and more secondary colonization. We conclude that lesion progression associated with Coralliophila may be associated with secondary colonization of coral tissues damaged by predator-induced trauma and necrosis. Importantly, variation at the cellular level should be considered when explaining interspecific differences in host responses in corals impacted by phenomena such as predation.

  10. Assessing the accuracy of oxygen isotopes and Sr/Ca as proxies of sea surface temperature at the extreme latitudinal limits of Porites corals

    NASA Astrophysics Data System (ADS)

    Hirabayashi, S.; Yokoyama, Y.; Suzuki, A.; Kawakubo, Y.; Miyairi, Y.; Okai, T.; Nojima, S.

    2014-12-01

    Oxygen isotope and Sr/Ca ratios in harmatypic coral skeletons are widely employed as proxies of sea-surface temperature (SST) in paleoclimatology, yet they are considered to be influenced from growth rate of corals. Corals in temperate regions have lower skeletal growth rate because of relatively stressful environment, in particular lower SST than those in the tropics or subtropics. Dependency on SST proxies from those effects are required to be validated to better understand paleo-environment using temperate corals. This study reports Sr/Ca-based SST reconstructions for three temperate Porites coral colonies (USB93, USB12-01, USB12-03) collected from Kyushu, Japan, near the northern latitudinal limits of Porites. Results clearly indicated that Sr/Ca reliably reproduced SST variation, independent from growth rate variations, in contrast to δ18O-based reconstruction (Hirabayashi et al., 2013, Geochemical Journal). The inter-colony variation of skeletal Sr/Ca of two Porites corals (USB12-01, USB12-03) were observed. This is attributed to the difference in calcification processes between so called "smooth type" and "sharp type" proposed by Gagan et al. (2012) as is defined by the ratio of tissue thickness/extension rate. According to these observations, summer SST reconstruction can be achieved by a limited number of coral specimens in a temperate region with comparable accuracy to tropical and subtropical corals.

  11. Environmental versus genetic influences on growth rates of the corals Pocillopora eydouxi and Porites lobata (Anthozoa: Scleractinia)

    USGS Publications Warehouse

    Smith, L.W.; Wirshing, H.H.; Baker, A.C.; Birkeland, C.

    2008-01-01

    Reciprocal transplant experiments of the corals Pocillopora eydouxi Milne Edwards & Haime and Porites lobata Dana were carried out for an 18-month period from September 2004 to March 2006 between two back reef pools on Ofu Island, American Samoa, to test environmental versus genetic effects on skeletal growth rates. Skeletal growth of P. eydouxi showed environmental but not genetic effects, resulting in doubling of growth in Pool 300 compared with Pool 400. There were no environmental or genetic effects on skeletal growth of P. lobata. Pool 300 had more frequent and longer durations of elevated seawater temperatures than Pool 400, characteristics likely to decrease rather than increase skeletal growth. Pool 300 also had higher nutrient levels and flow velocities than Pool 400, characteristics that may increase skeletal growth. However, higher nutrient levels would be expected to increase skeletal growth in both species, but there was no difference between the pools in P. lobata growth. P. eydouxi is much more common in high-energy environments than P. lobata; thus the higher flow velocities in Pool 300 than in Pool 400 may have positively affected skeletal growth of P. eydouxi while not having a detectable effect on P. lobata. The greater skeletal growth of P. eydouxi in Pool 300 occurred despite the presence of clade D zooxanthellae in several source colonies in Pool 300, a genotype known to result in greater heat resistance but slower skeletal growth. Increased skeletal growth rates in higher water motion may provide P. eydouxi a competitive advantage in shallow, high-energy enviromnents where competition for space is intense. ?? 2008 by University of Hawai'i Press. All rights reserved.

  12. Bacterial profiling of White Plague Disease in a comparative coral species framework.

    PubMed

    Roder, Cornelia; Arif, Chatchanit; Bayer, Till; Aranda, Manuel; Daniels, Camille; Shibl, Ahmed; Chavanich, Suchana; Voolstra, Christian R

    2014-01-01

    Coral reefs are threatened throughout the world. A major factor contributing to their decline is outbreaks and propagation of coral diseases. Due to the complexity of coral-associated microbe communities, little is understood in terms of disease agents, hosts and vectors. It is known that compromised health in corals is correlated with shifts in bacterial assemblages colonizing coral mucus and tissue. However, general disease patterns remain, to a large extent, ambiguous as comparative studies over species, regions, or diseases are scarce. Here, we compare bacterial assemblages of samples from healthy (HH) colonies and such displaying signs of White Plague Disease (WPD) of two different coral species (Pavona duerdeni and Porites lutea) from the same reef in Koh Tao, Thailand, using 16S rRNA gene microarrays. In line with other studies, we found an increase of bacterial diversity in diseased (DD) corals, and a higher abundance of taxa from the families that include known coral pathogens (Alteromonadaceae, Rhodobacteraceae, Vibrionaceae). In our comparative framework analysis, we found differences in microbial assemblages between coral species and coral health states. Notably, patterns of bacterial community structures from HH and DD corals were maintained over species boundaries. Moreover, microbes that differentiated the two coral species did not overlap with microbes that were indicative of HH and DD corals. This suggests that while corals harbor distinct species-specific microbial assemblages, disease-specific bacterial abundance patterns exist that are maintained over coral species boundaries.

  13. Decadal Variations in Western Pacific Warm Pool Dynamics as Evidenced by Porites Corals from Chuuk Atoll, Federated States of Micronesia

    NASA Astrophysics Data System (ADS)

    Massoll, J. L.; Wagner, A. J.; Anderson, D. M.; Lane, C.; Kim, J. K.; Lee, S. H.

    2014-12-01

    The Western Pacific Warm Pool (WPWP) encompasses some of the warmest sea surface temperatures (SSTs) of the world oceans. This region influences seasonal and decadal variability of the Intertropical Convergence Zone (ITCZ) and climate anomalies such as the El Niño-Southern Oscillation (ENSO). Long-term changes coupled with anomalous events like El Niño can greatly influence the position of the ITCZ and subsequently alter weather patterns on a global scale. WPWP dynamics may have contributed to the slowdown in global warming during the last decade. The processes that control these variations are complex, and gaining insight into these systems on decadal to centennial timescales is necessary to improve climate modeling and future predictions for drought or floods associated with global climate change. Chuuk Atoll (7°N, 152°E), located in the Federated States of Micronesia, is positioned within the WPWP at the northern extent of the mean boreal summer position of the ITCZ, making this location optimal for studying WPWP dynamics and ocean-atmosphere linkages. Two coral cores from the species Porites lobata were collected from the outer-atoll at Fannuk Island and the inner-atoll at Lobata Reef. Using stable isotope (δ18O and δ13C) composition and Sr/Ca trace metal analysis, the sites were identified as distinct hydrologic environments. Low seasonal variability in δ18O and Sr/Ca values at the outer-atoll site indicates a hydrologically-open system that is strongly influenced by the WPWP. At the inner-atoll site, δ18O and Sr/Ca values reflect a small seasonal SST cycle. In this hydrologically-restricted basin, the δ18O record is likely responding to salinity variations influenced by local climatology, specifically anomalously high or low precipitation events associated with ENSO. The average δ18O between 2003-2011 was 0.5‰ lighter at the inner-atoll site. These values can be interpreted as warmer sea surface temperatures and/or lower sea surface salinities

  14. Effect of light and brine shrimp on skeletal δ 13C in the Hawaiian coral Porites compressa: a tank experiment

    NASA Astrophysics Data System (ADS)

    Grottoli, Andréa G.

    2002-06-01

    Previous experimental fieldwork showed that coral skeletal δ 13C values decreased when solar intensity was reduced, and increased in the absence of zooplankton. However, actual seasonal changes in solar irradiance levels are typically less pronounced than those used in the previous experiment and the effect of increases in the consumption of zooplankton in the coral diet on skeletal δ 13C remains relatively unknown. In the present study, the effects of four different light and heterotrophy regimes on coral skeletal δ 13C values were measured. Porites compressa corals were grown in outdoor flow-through tanks under 112%, 100%, 75%, and 50% light conditions at the Hawaii Institute of Marine Biology, Hawaii. In addition, corals were fed either zero, low, medium, or high concentrations of brine shrimp. Decreases in light from 100% resulted in significant decreases in δ 13C that is most likely due to a corresponding decrease in photosynthesis. Increases in light to 112% also resulted in a decrease in δ 13C values. This latter response may be a consequence of photoinhibition. The overall curved response in δ 13C values was described by a significant quadratic function. Increases in brine shrimp concentrations resulted in increased skeletal δ 13C levels. This unexpected outcome appears to be attributable to enhanced nitrogen supply associated with the brine shrimp diet which led to increased zooxanthellae concentrations, increased photosynthesis rates, and thus increased δ 13C values. This result highlights the potential influence of nutrients from heterotrophically acquired carbon in maintaining the zooxanthellae-host symbiosis in balance. In addition, evidence is presented that suggests that coral skeletal growth and δ 13C are decoupled. These results increase our knowledge of how light and heterotrophy affects the δ 13C of coral skeletons.

  15. Coral reef degradation and metabolic performance of the scleractinian coral Porites lutea under anthropogenic impact along the NE coast of Hainan Island, South China Sea

    NASA Astrophysics Data System (ADS)

    Roder, Cornelia; Wu, Zhongjie; Richter, Claudio; Zhang, Jing

    2013-04-01

    Hainan's coast provides favorable climatic, geochemical and biogeographic conditions for the development of extensive coral reefs in China. Observations in five reefs along the NE coast of Hainan showed, however, that the overall density of mobile macrofauna is low and key functional groups such as browsing, scraping or excavating herbivore fish are missing altogether. Coral diseases, partial mortality or tissue degradation are abundant and growth of macroalgal space competitors extensive. Signs of eutrophication, siltation and destructive fishing practices are evident resulting in a strongly altered environment unfavorable for coral recruitment success and survival. Acclimation to the anthropogenically altered conditions in the massive coral Porites lutea occurs at the cost of a decreased photosynthesis: respiration ratio reducing the regenerative capacity of these key framebuilding organisms. Even though, on the organismal level, corals are able to cope with these stressful conditions, a shift is imminent on the ecosystem level from a coral reef to a macroalgae-dominated community if land-based disturbance prevails unabated.

  16. A new method for calibrating a boron isotope paleo-pH proxy using massive Porites corals

    NASA Astrophysics Data System (ADS)

    Kubota, Kaoru; Yokoyama, Yusuke; Ishikawa, Tsuyoshi; Suzuki, Atsushi

    2015-09-01

    The boron isotope ratio (δ11B) of marine biogenic carbonates can reconstruct pH and pCO2 of seawater, and potentially CO2 concentration in the atmosphere. To date, δ11B-pHSW calibration has been proposed via culturing experiments, where calcifying organisms are cultured under artificially acidified seawater. However, in scleractinian corals, reconstructed pH values using culture-based calibrations do not agree well with actual observations of seawater CO2 chemistry. Thus, another approach is needed to establish a more reliable calibration method. In this study, we established field-based calibrations for Chichijima and Tahiti, both located in subtropical gyres where surface seawater is close to CO2 equilibrium. We suggest a new approach to calibration of δ11B-pH in which the long-term δ11B variation of massive Porites corals is compared with the decreasing pH trend (i.e., ocean acidification) that has occurred since the Industrial Revolution. This calibration will offer a new avenue for studying seawater CO2 chemistry using coral δ11B in diverse settings, such as upwelling regions, coral reefs, and coastal areas.

  17. Growth anomalies on the coral genera Acropora and Porites are strongly associated with host density and human population size across the Indo-Pacific.

    PubMed

    Aeby, Greta S; Williams, Gareth J; Franklin, Erik C; Haapkyla, Jessica; Harvell, C Drew; Neale, Stephen; Page, Cathie A; Raymundo, Laurie; Vargas-Ángel, Bernardo; Willis, Bette L; Work, Thierry M; Davy, Simon K

    2011-02-18

    Growth anomalies (GAs) are common, tumor-like diseases that can cause significant morbidity and decreased fecundity in the major Indo-Pacific reef-building coral genera, Acropora and Porites. GAs are unusually tractable for testing hypotheses about drivers of coral disease because of their pan-Pacific distributions, relatively high occurrence, and unambiguous ease of identification. We modeled multiple disease-environment associations that may underlie the prevalence of Acropora growth anomalies (AGA) (n = 304 surveys) and Porites growth anomalies (PGA) (n = 602 surveys) from across the Indo-Pacific. Nine predictor variables were modeled, including coral host abundance, human population size, and sea surface temperature and ultra-violet radiation anomalies. Prevalence of both AGAs and PGAs were strongly host density-dependent. PGAs additionally showed strong positive associations with human population size. Although this association has been widely posited, this is one of the first broad-scale studies unambiguously linking a coral disease with human population size. These results emphasize that individual coral diseases can show relatively distinct patterns of association with environmental predictors, even in similar diseases (growth anomalies) found on different host genera (Acropora vs. Porites). As human densities and environmental degradation increase globally, the prevalence of coral diseases like PGAs could increase accordingly, halted only perhaps by declines in host density below thresholds required for disease establishment.

  18. Growth anomalies on the coral genera Acropora and Porites are strongly associated with host density and human population size across the Indo-Pacific

    USGS Publications Warehouse

    Aeby, G.S.; Williams, G.J.; Franklin, E.C.; Haapkyla, J.; Harvell, C.D.; Neale, S.; Page, C.A.; Raymundo, L.; Vargas-Angel, B.; Willis, B.L.; Work, T.M.; Davy, S.K.

    2011-01-01

    Growth anomalies (GAs) are common, tumor-like diseases that can cause significant morbidity and decreased fecundity in the major Indo-Pacific reef-building coral genera, Acropora and Porites. GAs are unusually tractable for testing hypotheses about drivers of coral disease because of their pan-Pacific distributions, relatively high occurrence, and unambiguous ease of identification. We modeled multiple disease-environment associations that may underlie the prevalence of Acropora growth anomalies (AGA) (n = 304 surveys) and Porites growth anomalies (PGA) (n = 602 surveys) from across the Indo-Pacific. Nine predictor variables were modeled, including coral host abundance, human population size, and sea surface temperature and ultra-violet radiation anomalies. Prevalence of both AGAs and PGAs were strongly host density-dependent. PGAs additionally showed strong positive associations with human population size. Although this association has been widely posited, this is one of the first broad-scale studies unambiguously linking a coral disease with human population size. These results emphasize that individual coral diseases can show relatively distinct patterns of association with environmental predictors, even in similar diseases (growth anomalies) found on different host genera (Acropora vs. Porites). As human densities and environmental degradation increase globally, the prevalence of coral diseases like PGAs could increase accordingly, halted only perhaps by declines in host density below thresholds required for disease establishment.

  19. Effects of predator exclusion on recruit survivorship in an octocoral ( Briareum asbestinum) and a scleractinian coral ( Porites astreoides)

    NASA Astrophysics Data System (ADS)

    Evans, M. J.; Coffroth, M. A.; Lasker, H. R.

    2013-06-01

    Recruits of the Caribbean scleractinian coral Porites astreoides and the octocoral Briareum asbestinum were established on artificial substrata and reared on a reef in cages designed to exclude various classes of organisms known to feed on corals. Post-settlement survivorship of recruits was measured for periods of 2 weeks ( B. asbestinum) and 1 month ( P. astreoides) on East Turtle Reef in the Florida Keys during May and June 2010. Predator exclusion did not affect survivorship among P. astreoides recruits during the study. Recruits of B. asbestinum experienced lower survivorship in treatments that allowed access by fish compared with fish exclusion treatments. The results indicate that predation may be an important determinant of post-settlement mortality among B. asbestinum recruits, and fishes are the primary contributors to predation-induced mortality. B. asbestinum recruit survivorship differed by an order of magnitude between recruits in the control condition and those in the predator exclusion (0.087 and 0.372, respectively). The findings illustrate the need to consider the effects of interactions early in life on the survival, propagation, and recovery of coral populations.

  20. Understanding cold bias: Variable response of skeletal Sr/Ca to seawater pCO2 in acclimated massive Porites corals

    PubMed Central

    Cole, Catherine; Finch, Adrian; Hintz, Christopher; Hintz, Kenneth; Allison, Nicola

    2016-01-01

    Coral skeletal Sr/Ca is a palaeothermometer commonly used to produce high resolution seasonal sea surface temperature (SST) records and to investigate the amplitude and frequency of ENSO and interdecadal climate events. The proxy relationship is typically calibrated by matching seasonal SST and skeletal Sr/Ca maxima and minima in modern corals. Applying these calibrations to fossil corals assumes that the temperature sensitivity of skeletal Sr/Ca is conserved, despite substantial changes in seawater carbonate chemistry between the modern and glacial ocean. We present Sr/Ca analyses of 3 genotypes of massive Porites spp. corals (the genus most commonly used for palaeoclimate reconstruction), cultured under seawater pCO2 reflecting modern, future (year 2100) and last glacial maximum (LGM) conditions. Skeletal Sr/Ca is indistinguishable between duplicate colonies of the same genotype cultured under the same conditions, but varies significantly in response to seawater pCO2 in two genotypes of Porites lutea, whilst Porites murrayensis is unaffected. Within P. lutea, the response is not systematic: skeletal Sr/Ca increases significantly (by 2–4%) at high seawater pCO2 relative to modern in both genotypes, and also increases significantly (by 4%) at low seawater pCO2 in one genotype. This magnitude of variation equates to errors in reconstructed SST of up to −5 °C. PMID:27241795

  1. Understanding cold bias: Variable response of skeletal Sr/Ca to seawater pCO2 in acclimated massive Porites corals

    NASA Astrophysics Data System (ADS)

    Cole, Catherine; Finch, Adrian; Hintz, Christopher; Hintz, Kenneth; Allison, Nicola

    2016-05-01

    Coral skeletal Sr/Ca is a palaeothermometer commonly used to produce high resolution seasonal sea surface temperature (SST) records and to investigate the amplitude and frequency of ENSO and interdecadal climate events. The proxy relationship is typically calibrated by matching seasonal SST and skeletal Sr/Ca maxima and minima in modern corals. Applying these calibrations to fossil corals assumes that the temperature sensitivity of skeletal Sr/Ca is conserved, despite substantial changes in seawater carbonate chemistry between the modern and glacial ocean. We present Sr/Ca analyses of 3 genotypes of massive Porites spp. corals (the genus most commonly used for palaeoclimate reconstruction), cultured under seawater pCO2 reflecting modern, future (year 2100) and last glacial maximum (LGM) conditions. Skeletal Sr/Ca is indistinguishable between duplicate colonies of the same genotype cultured under the same conditions, but varies significantly in response to seawater pCO2 in two genotypes of Porites lutea, whilst Porites murrayensis is unaffected. Within P. lutea, the response is not systematic: skeletal Sr/Ca increases significantly (by 2–4%) at high seawater pCO2 relative to modern in both genotypes, and also increases significantly (by 4%) at low seawater pCO2 in one genotype. This magnitude of variation equates to errors in reconstructed SST of up to ‑5 °C.

  2. Evidence for a host role in thermotolerance divergence between populations of the mustard hill coral (Porites astreoides) from different reef environments.

    PubMed

    Kenkel, C D; Goodbody-Gringley, G; Caillaud, D; Davies, S W; Bartels, E; Matz, M V

    2013-08-01

    Studying the mechanisms that enable coral populations to inhabit spatially varying thermal environments can help evaluate how they will respond in time to the effects of global climate change and elucidate the evolutionary forces that enable or constrain adaptation. Inshore reefs in the Florida Keys experience higher temperatures than offshore reefs for prolonged periods during the summer. We conducted a common garden experiment with heat stress as our selective agent to test for local thermal adaptation in corals from inshore and offshore reefs. We show that inshore corals are more tolerant of a 6-week temperature stress than offshore corals. Compared with inshore corals, offshore corals in the 31 °C treatment showed significantly elevated bleaching levels concomitant with a tendency towards reduced growth. In addition, dinoflagellate symbionts (Symbiodinium sp.) of offshore corals exhibited reduced photosynthetic efficiency. We did not detect differences in the frequencies of major (>5%) haplotypes comprising Symbiodinium communities hosted by inshore and offshore corals, nor did we observe frequency shifts ('shuffling') in response to thermal stress. Instead, coral host populations showed significant genetic divergence between inshore and offshore reefs, suggesting that in Porites astreoides, the coral host might play a prominent role in holobiont thermotolerance. Our results demonstrate that coral populations inhabiting reefs <10-km apart can exhibit substantial differences in their physiological response to thermal stress, which could impact their population dynamics under climate change.

  3. Reconstructing skeletal fiber arrangement and growth mode in the coral Porites lutea (Cnidaria, Scleractinia): a confocal Raman microscopy study

    NASA Astrophysics Data System (ADS)

    Wall, M.; Nehrke, G.

    2012-11-01

    Confocal Raman microscopy (CRM) mapping was used to investigate the microstructural arrangement and organic matrix distribution within the skeleton of the coral Porites lutea. Relative changes in the crystallographic orientation of crystals within the fibrous fan-system could be mapped, without the need to prepare thin sections, as required if this information is obtained by polarized light microscopy. Simultaneously, incremental growth lines can be visualized without the necessity of etching and hence alteration of sample surface. Using these methods two types of growth lines could be identified: one corresponds to the well-known incremental growth layers, whereas the second type of growth lines resemble denticle finger-like structures (most likely traces of former spines or skeletal surfaces). We hypothesize that these lines represent the outer skeletal surface before another growth cycle of elongation, infilling and thickening of skeletal areas continues. We show that CRM mapping with high spatial resolution can significantly improve our understanding of the micro-structural arrangement and growth patterns in coral skeletons.

  4. Protein expression and genetic structure of the coral Porites lobata in an environmentally extreme Samoan back reef: Does host genotype limit phenotypic plasticity?

    USGS Publications Warehouse

    Barshis, D.J.; Stillman, J.H.; Gates, R.D.; Toonen, R.J.; Smith, L.W.; Birkeland, C.

    2010-01-01

    The degree to which coral reef ecosystems will be impacted by global climate change depends on regional and local differences in corals' susceptibility and resilience to environmental stressors. Here, we present data from a reciprocal transplant experiment using the common reef building coral Porites lobata between a highly fluctuating back reef environment that reaches stressful daily extremes, and a more stable, neighbouring forereef. Protein biomarker analyses assessing physiological contributions to stress resistance showed evidence for both fixed and environmental influence on biomarker response. Fixed influences were strongest for ubiquitin-conjugated proteins with consistently higher levels found in back reef source colonies both pre and post-transplant when compared with their forereef conspecifics. Additionally, genetic comparisons of back reef and forereef populations revealed significant population structure of both the nuclear ribosomal and mitochondrial genomes of the coral host (FST = 0.146 P < 0.0001, FST = 0.335 P < 0.0001 for rDNA and mtDNA, respectively), whereas algal endosymbiont populations were genetically indistinguishable between the two sites. We propose that the genotype of the coral host may drive limitations to the physiological responses of these corals when faced with new environmental conditions. This result is important in understanding genotypic and environmental interactions in the coral algal symbiosis and how corals may respond to future environmental changes. ?? 2010 Blackwell Publishing Ltd.

  5. Short-term and latent post-settlement effects associated with elevated temperature and oxidative stress on larvae from the coral Porites astreoides

    NASA Astrophysics Data System (ADS)

    Ross, C.; Ritson-Williams, R.; Olsen, K.; Paul, V. J.

    2013-03-01

    Coral reefs across the Caribbean are undergoing unprecedented rates of decline in coral cover during the last three decades, and coral recruitment is one potential process that could aid the recovery of coral populations. To better understand the effects of climate change on coral larval ecology, the larvae of Porites astreoides were studied to determine the immediate and post-settlement effects of elevated temperature and associated oxidative stress. Larvae of Porites astreoides were exposed to 27 °C (ambient) and +3.0 °C (elevated temperature) seawater for a short duration of 24 h; then, a suite of physiological parameters were measured to determine the extent of sublethal stress. Following the +3.0 °C treatment, larvae did not show a significant difference in maximum quantum yield of PSII ( F v/ F m) or respiratory demand when compared to controls maintained at 27 °C. The addition of micromolar concentrations of hydrogen peroxide did not impact respiration or photochemical efficiency. Catalase activity in the larvae increased (>60 %) following exposure to elevated temperature when compared to the controls. Short-term larval survival and settlement and metamorphosis were not affected by increased temperature or the H2O2 treatment. However, the settled spat that were exposed to elevated temperature underwent a 99 % reduction in survival compared to 90 % reduction for the control spat when examined 24 days following the deployment of 4-day-old settled spat on settlement tiles in the field. These results show that short-term exposure to some stressors might have small impacts on coral physiology, and no effects on larval survival, settlement and metamorphosis. However, due to post-settlement mortality, these stressors can cause a significant reduction in coral recruitment.

  6. Twelve-year Geochemical Records Of The East Asian Summer And Winter Monsoons And Terrestrial Sediment Transport In A Porites Coral From Son Tra Island, Cental Vietnam

    NASA Astrophysics Data System (ADS)

    Chang, C.; Shen, C.; Chiang, H.; Chen, Y.; Lam, D.; Ngai, N.

    2006-12-01

    The climate in the South China Sea (SCS), a semi-closed ocean basin with a narrow opening in the north to the Western Pacific Ocean, is mainly constrained by the East Asian summer and winter monsoons. Due to the limited instrumental data, the quantitative evaluation of both influences on local and regional areas is still beyond the capacity of climate models. The geochemical proxy records in coral skeletons provide a potential way to retrieve the history of hydrological and climatic conditions with weekly to monthly resolution. We present geochemical proxy records in a 12-year modern Porites coral collected from Son Tra Island, central Vietnam in June, 2005. Three features are exhibited as follows. (1) The winter data of coral δ18O match well with the instrumental SST observations. This consistency indicates that the winter coral δ18O can reflect the regional hydrological conditions, which is dominated by the East Asian winter monsoon. (2) The variation of interannual summer coral δ18O values differ from that of instrumental SST record. The episodic enriched coral δ18O in summer might reflect sea surface water cooling events, triggered by enhancement of the East Asian summer monsoon (EASM) and/or local salinity increase. (3) The diachronous characteristics of seasonal and interannual trends among different elements, such as Al, Ba, Fe and Cd, shows the dynamic natural of EASM-induced seasonal upwelling and the variability of terrestrial sediment transport over the past 12 years in this area.

  7. Evaluation of Mn and Fe in coral skeletons ( Porites spp.) as proxies for sediment loading and reconstruction of 50 yrs of land use on Ishigaki Island, Japan

    NASA Astrophysics Data System (ADS)

    Inoue, Mayuri; Ishikawa, Daisaku; Miyaji, Tsuzumi; Yamazaki, Atsuko; Suzuki, Atsushi; Yamano, Hiroya; Kawahata, Hodaka; Watanabe, Tsuyoshi

    2014-06-01

    Manganese (Mn) and iron (Fe) concentrations were measured in coral skeletons ( Porites spp.) collected from the Todoroki River on Ishigaki Island, Japan, to reconstruct the history of land use in the river catchment area. We prepared (1) five bulk samples to investigate the present spatial distribution and (2) micro-samples from two long cores to study the temporal variability of sediment loading from the Todoroki River. The existing state of the elements Mn and Fe in bulk coral skeleton samples was examined by a chemical cleaning experiment. The results of the experiment suggested that Fe was not incorporated into the crystal lattice of the coral skeleton but that Mn was incorporated, as previously reported. The bulk sample data, with and without chemical cleaning, indicated that the spatial distribution of both elements in corals collected along a sampling line from the river mouth toward the reef crest was complex and most likely reflected salinity changes and the amount of suspended particulate matter. The temporal variation of Mn and Fe, in particular the variation of baseline/background levels, mainly reflected the history of land development on Ishigaki Island. In addition, Mn showed clear seasonal variability that appeared to be controlled by a combination of temperature, primary productivity, and precipitation. The results of the present study suggest that Mn may be a useful proxy for river discharge or biological activity depending on local marine conditions, if the specific behavior of Mn at the coral growth site is known.

  8. Bacterial associates of two Caribbean coral species reveal species-specific distribution and geographic variability.

    PubMed

    Morrow, Kathleen M; Moss, Anthony G; Chadwick, Nanette E; Liles, Mark R

    2012-09-01

    Scleractinian corals harbor microorganisms that form dynamic associations with the coral host and exhibit substantial genetic and ecological diversity. Microbial associates may provide defense against pathogens and serve as bioindicators of changing environmental conditions. Here we describe the bacterial assemblages associated with two of the most common and phylogenetically divergent reef-building corals in the Caribbean, Montastraea faveolata and Porites astreoides. Contrasting life history strategies and disease susceptibilities indicate potential differences in their microbiota and immune function that may in part drive changes in the composition of coral reef communities. The ribotype structure and diversity of coral-associated bacteria within the surface mucosal layer (SML) of healthy corals were assessed using denaturing gradient gel electrophoresis (DGGE) fingerprinting and 454 bar-coded pyrosequencing. Corals were sampled at disparate Caribbean locations representing various levels of anthropogenic impact. We demonstrate here that M. faveolata and P. astreoides harbor distinct, host-specific bacteria but that specificity varies by species and site. P. astreoides generally hosts a bacterial assemblage of low diversity that is largely dominated by one bacterial genus, Endozoicomonas, within the order Oceanospirillales. The bacterial assemblages associated with M. faveolata are significantly more diverse and exhibit higher specificity at the family level than P. astreoides assemblages. Both corals have more bacterial diversity and higher abundances of disease-related bacteria at sites closer to the mainland than at those furthest away. The most diverse bacterial taxa and highest relative abundance of disease-associated bacteria were seen for corals near St. Thomas, U.S. Virgin Islands (USVI) (2.5 km from shore), and the least diverse taxa and lowest relative abundance were seen for corals near our most pristine site in Belize (20 km from shore). We conclude

  9. Health status of corals surrounding Kish Island, Persian Gulf.

    PubMed

    Alidoost Salimi, Mahsa; Mostafavi, Pargol Ghavam; Fatemi, Seyyed Mohammad; Aeby, Greta S

    2017-03-30

    Corals in the Persian Gulf exist in a harsh environment with extreme temperature and salinity fluctuations. Understanding the health of these hardy corals may prove useful for predicting the survival of other marine organisms facing the impacts of global climate change. In this study, the health state of corals was surveyed along belt transects at 4 sites on the east side of Kish Island, Iran. Corals had a patchy distribution, low colony densities and species diversity, and were dominated by Acropora, Porites, and Dipsastrea. We found chronic sedimentation on corals, a high prevalence of old partial mortality, abundant bioeroders, and overgrowth of corals by sponges and bryozoans. These are all signs indicating suboptimal environmental conditions for coral reefs. Four types of tissue loss lesions consistent with disease were found: Porites multi-focal chronic tissue loss, Porites peeling tissue loss, Porites focal chronic tissue loss, and Dipsastrea focal sub-acute tissue loss. Overall disease prevalence was 3.6% and there were significant differences in prevalence among the 3 most abundant coral genera. Acropora was numerically dominant within transects yet showed no signs of disease, whereas Porites had a 14% disease prevalence, indicating differential susceptibility to disease among genera. Other coral lesions included pigmentation response in Porites associated with algae invasion or boring organisms, sponge overgrowth, and mucus sheathing in Dipsastrea. The Persian Gulf region is understudied, and this represents one of the first quantitative surveys of coral health and disease on these reefs.

  10. Sex-associated variations in coral skeletal oxygen and carbon isotopic composition of Porites panamensis in the southern Gulf of California

    NASA Astrophysics Data System (ADS)

    Cabral-Tena, R. A.; Sánchez, A.; Reyes-Bonilla, H.; Ruvalcaba-Díaz, A. H.; Balart, E. F.

    2015-11-01

    Coral δ18O variations are used as a proxy for changes in near sea surface temperature and seawater isotope composition. Skeletal δ13C of coral is frequently used as a proxy for solar radiation because most of its variability is controlled by an interrelationship between three processes: photosynthesis, respiration, and feeding. Coral growth rate is known to influence the δ18O and δ13C isotope record to a lesser extent. Recent published data show differences in growth parameters between female and male coral; thus, skeletal δ18O and δ13C are hypothesized to be different in each sex. To assess this difference, this study describes changes in the skeletal δ18O and δ13C record of four female and six male Porites panamensis coral collected in Bahía de La Paz, whose growth bands spanned 12 years. The isotopic data were compared to SST, precipitation, PAR, chlorophyll a, and skeletal growth parameters. Porites panamensis is a known gonochoric brooder whose growth parameters are different in females and males. Splitting the data by sexes explained 81 and 93 % of the differences of δ18O, and of δ13C, respectively, in the isotope record between colonies. Both isotope records were different between sexes. δ18O was higher in female colonies than in male colonies, with a 0.31 ‰ difference; δ13C was lower in female colonies, with a 0.28 ‰ difference. A difference in the skeletal δ18O implies an error in SST estimates of ≈ 1.0 °C to ≈ 2.6 °C. The δ18O records showed a seasonal pattern that corresponded to SST, with low correlation coefficients (-0.45, -0.32), and gentle slopes (0.09 ‰ °C-1, 0.10 ‰ °C-1) of the δ18O-SST relation. Seasonal variation in coral δ18O represents only 52.37 and 35.66 % of the SST cycle; 29.72 and 38.53 % can be attributed to δ18O variability in seawater. δ13C data did not correlate with any of the environmental variables; therefore, variations in skeletal δ13C appear to be driven mainly by metabolic effects. Our

  11. NOAA Lists 20 Coral Species as Threatened

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2014-09-01

    Twenty coral species have been listed as threatened under the U.S. Endangered Species Act (ESA), the National Oceanic and Atmospheric Administration (NOAA) announced on 27 August. This is NOAA's largest ESA rule making. The coral species include 15 found in the Indo-Pacific region and 5 that are located in the Caribbean. They join two other Caribbean coral species that NOAA listed as threatened in 2006.

  12. Investigating coral hyperspectral properties across coral species and coral state using hyperspectral imaging

    NASA Astrophysics Data System (ADS)

    Mehrubeoglu, Mehrube; Smith, Dustin K.; Smith, Shane W.; Strychar, Kevin B.; McLauchlan, Lifford

    2013-09-01

    Coral reefs are one of the most diverse and threatened ecosystems in the world. Corals worldwide are at risk, and in many instances, dying due to factors that affect their environment resulting in deteriorating environmental conditions. Because corals respond quickly to the quality of the environment that surrounds them, corals have been identified as bioindicators of water quality and marine environmental health. The hyperspectral imaging system is proposed as a noninvasive tool to monitor different species of corals as well as coral state over time. This in turn can be used as a quick and non-invasive method to monitor environmental health that can later be extended to climate conditions. In this project, a laboratory-based hyperspectral imaging system is used to collect spectral and spatial information of corals. In the work presented here, MATLAB and ENVI software tools are used to view and process spatial information and coral spectral signatures to identify differences among the coral data. The results support the hypothesis that hyperspectral properties of corals vary among different coral species, and coral state over time, and hyperspectral imaging can be a used as a tool to document changes in coral species and state.

  13. The effects of ultraviolet radiation on growth and bleaching in three species of Hawaiian coral

    SciTech Connect

    Goodman, G.D. )

    1990-01-09

    Long term exposure to ultraviolet radiation is harmful to many organisms, including hermatypic corals, which obtain much of their nutrition from photosynthetic zooxanthellae. Therefore, increased UV radiation from atmospheric ozone depletion could inhibit growth of such corals. Moreover, coral bleaching, which has been attributed to loss of pigment and/or expulsion of zooxanthellae, may be a specific response to UV light. Does UV-A reduce skeletal growth or influence population density and pigment content of zooxanthellae In addition, do zooxanthellae migrate to shaded areas of the colony to avoid ultraviolet light Using alizarin red stain and suitable filters, I compared the stain and suitable filters, I compared the effects of UV-A (320-400nm) and full-spectrum UV (280-400nm) on the skeletal growth of two Hawaiian corals, Montipora verrucosa, Pocillopora damicornis, in situ. In the perforate corals, M. Verrucosa and Porites compressa, I measured concentration of zooxanthellae and their chlorophyll content to quantify bleaching in response to UV light. Reduction in skeletal growth by the two corals in response to different ranges of UV light appears to be species specific. Bleaching by UV appears to be characterized by an initial loss of pigment followed by the expulsion and migration of the zooxanthellae to shaded areas of the colony. Differences in tolerance and adaptation to decreasing ozone levels and increasing UV light should confer a competitive advantage on various species and morphologies of reef-building corals.

  14. High-resolution Sr/Ca ratios in a Porites lutea coral from Lakshadweep Archipelago, southeast Arabian Sea: An example from a region experiencing steady rise in the reef temperature

    NASA Astrophysics Data System (ADS)

    Sagar, Netramani; Hetzinger, Steffen; Pfeiffer, Miriam; Masood Ahmad, Syed; Dullo, Wolf-Christian; Garbe-Schönberg, Dieter

    2016-01-01

    Here we present the first record of Sr/Ca variability in a massive Porites lutea coral from the Lakshadweep Archipelago, Arabian Sea. The annual mean sea surface temperature (SST) in this region and the surrounding areas has increased steadily in the recent past. During some major El Niño events, SSTs are even higher, imposing additional thermal-stress on corals, episodically leading to coral bleaching. We infer from the coral-Sr/Ca record (1981-2008) that during some of these events high and persistent SSTs lead to a dampening of the temperature signal in coral-Sr/Ca, impairing the coral's ability to record full scale warming. Thus, coral-Sr/Ca may provide a history of past El Niño Southern-Oscillation (ENSO) induced thermal-stress episodes, which are a recurrent feature also seen in cross-spectral analysis between coral-Sr/Ca and the Nino3.4 index. Despite the impact of episodical thermal-stress during major El Niño events, our coral proxy faithfully records the seasonal monsoon-induced summer cooling on the order of ˜2.3°C. Calibration of coral-Sr/Ca with instrumental grid-SST data shows significant correlation to regional SST and monsoon variability. Hence, massive Porites corals of this region are highly valuable archives for reconstructing long-term changes in SST, strongly influenced by monsoon variability on seasonal scales. More importantly, our data show that this site with increasing SST is an ideal location for testing the future effects of the projected anthropogenic SST increase on coral reefs that are already under thermal-stress worldwide.

  15. Skeletal isotope records of growth perturbations in Porites corals during the 1997-1998 mass bleaching event

    NASA Astrophysics Data System (ADS)

    Suzuki, A.; Gagan, M.; Fabricius, K.; Isdale, P.; Yukino, I.; Kawahata, H.

    2003-04-01

    Severe coral bleaching occurred throughout the tropics in 1997/98. We report skeletal UV fluorescence, oxygen isotope, and carbon isotope evidence for perturbations in coral skeletal growth due to bleaching at Ishigaki Island, Japan, and Pandora Reef, Great Barrier Reef. Bleached corals showed abrupt reductions in skeletal extension rate immediately after summer temperature maxima, indicating that bleaching inhibits coral calcification. A colony growing at the low tide line in Ishigaki exhibited clear blue UV fluorescent bands associated with recurrent growth interruptions. Based on the length of time-gaps observed in the annual isotopic cycle, the typical time required for a coral to recover from bleaching is estimated to be about 5--6 months. The effect of bleaching on the oxygen isotope ratio -- temperature relationship was negligible. However, the Ishigaki corals showed lower carbon isotope ratios during bleaching indicating depressed coral metabolism associated with a reduction in calcification. In contrast, skeletal carbon isotope ratios in the Pandora Reef corals exhibited little change in response to bleaching. This is because the records for Pandora Reef were derived from the shaded sides of coral colonies, where algal photosynthesis was particularly slow prior to bleaching, thus subduing the carbon isotope response to bleaching. Taken together, the isotopic and UV fluorescence signals can be used to reconstruct past bleaching events.

  16. Stress response of two coral species in the Kavaratti atoll of the Lakshadweep Archipelago, India

    NASA Astrophysics Data System (ADS)

    Harithsa, Shashank; Raghukumar, Chandralata; Dalal, S. G.

    2005-11-01

    Frequent occurrences of coral bleaching and the ensuing damage to coral reefs have generated interest in documenting stress responses that precede bleaching. The objective of this study was to assess and compare physiological changes in healthy, semi-bleached and totally bleached colonies of two coral species, Porites lutea and Acropora formosa, during a natural bleaching event in the Lakshadweep Archipelago in the Arabian Sea to determine the traits that will be useful in the diagnosis of coral health. In April 2002, three “health conditions” were observed as “appearing healthy,” “semi-bleached” and “bleached” specimens for two dominant and co-occurring coral species in these islands. Changes in the pigment composition, zooxanthellae density (ZD), mitotic index (MI) of zooxanthellae, RNA/DNA ratios and protein profile in the two coral species showing different levels of bleaching in the field were compared to address the hypothesis of no difference in health condition between species and bleaching status. The loss in chlorophyll (chl) a, chl c and ZD in the transitional stage of semi-bleaching in the branched coral A. formosa was 80, 75 and 80%, respectively. The losses were much less in the massive coral P. lutea, being 20, 50 and 25%, respectively. The decrease in zooxanthellar density and chl a was accompanied by an increased MI of zooxanthellae and RNA/DNA ratios in both the species. There was an increase in accumulation of lipofuscin granules in partially bleached P. lutea tissue, which is an indication of cellular senescence. Multivariate statistical analyses showed that colonies of P. lutea ranked in different health conditions differed significantly in chl a, chl c, ZD, RNA/DNA ratios, and protein concentrations, whereas in A. formosa chl a, chl c, chl a/ c, phaeopigments and MI contributed to the variance between health conditions.

  17. SYMBIODINIUM ISOLATES FROM STONY CORAL: ISOLATION, GROWTH CHARACTERISTICS AND EFFECTS OF UV IRRADIATION

    EPA Science Inventory

    Symbiodinium spp. Isolates from Stony Coral: Isolation, Growth Characteristics and Effects of UV Irradiation (Abstract). J. Phycol. 37(3):42-43.

    Symbiodinium species were isolated from Montipora capitata, Acropora palmata and two field samples of Porites porites. Cultures ...

  18. Competitive strategies of soft corals (Coelenterata: Octocorallia): Allelopathic effects on selected scleractinian corals

    NASA Astrophysics Data System (ADS)

    Sammarco, P. W.; Coll, J. C.; La Barre, S.; Willis, B.

    1983-09-01

    A striking retardation of grwoth was observed in the scleractinian coral Pavona cactus (Coelenterata: Scleractinia) growing in the vicinity of the soft coral Sinularia flexibilis (Coelenterata: Alcyonacea). More extensive field observations of naturally occurring interactions between soft corals and scleractinian corals suggested that members of the former group can be the more effective competitors for space on hard substrate. To test this hypothesis, colonies of three soft corals, Lobophytum pauciflorum, Sinularia pavida, and Xenia sp. aff. danae, were relocated next to stands of two hard corals, Pavona cactus and Porites andrewsi (=Porites cylindrica), and compared with undisturbed control areas. In areas where soft corals and scleractinian corals were in direct contact, significantly high levels of local mortality in the latter occurred in three of the six interaction pairs. One soft coral, L. pauciflorum, also caused extensive and significant mortality in Porites andrewsi in a non-contact situation. The scleractinian corals had no effect on the soft corals considered here. These results indicate that soft corals can effectively compete for space against hard corals. Furthermore, it is inferred that toxic exudates from the soft coral might be responsible for causing localized mortality in hard corals, since extensive mortality occurred in certain cases in the absence of contact. Competitive abilities of soft corals in interactions with hard corals varied in a species-specific manner. Susceptibility of hard corals to competitive mechanisms utilized by soft corals, particularly allelopathic ones, likewise varied species-specifically. It is commonly believed that the adaptive value of toxic compounds in soft corals stems from their effectiveness as a chemical defence mechanism in predator-prey interactions. This study has demonstrated their further role as allelopathic agents in interspecific competitive interactions.

  19. Testing the genetic predictions of a biogeographical model in a dominant endemic Eastern Pacific coral (Porites panamensis) using a genetic seascape approach

    PubMed Central

    Saavedra-Sotelo, Nancy C; Calderon-Aguilera, Luis E; Reyes-Bonilla, Héctor; Paz-García, David A; López-Pérez, Ramón A; Cupul-Magaña, Amilcar; Cruz-Barraza, José A; Rocha-Olivares, Axayácatl

    2013-01-01

    The coral fauna of the Eastern Tropical Pacific (ETP) is depauperate and peripheral; hence, it has drawn attention to the factors allowing its survival. Here, we use a genetic seascape approach and ecological niche modeling to unravel the environmental factors correlating with the genetic variation of Porites panamensis, a hermatypic coral endemic to the ETP. Specifically, we test if levels of diversity and connectivity are higher among abundant than among depauperate populations, as expected by a geographically relaxed version of the Abundant Center Hypothesis (rel-ACH). Unlike the original ACH, referring to a geographical center of distribution of maximal abundance, the rel-ACH refers only to a center of maximum abundance, irrespective of its geographic position. The patterns of relative abundance of P. panamensis in the Mexican Pacific revealed that northern populations from Baja California represent its center of abundance; and southern depauperate populations along the continental margin are peripheral relative to it. Genetic patterns of diversity and structure of nuclear DNA sequences (ribosomal DNA and a single copy open reading frame) and five alloenzymatic loci partially agreed with rel-ACH predictions. We found higher diversity levels in peninsular populations and significant differentiation between peninsular and continental colonies. In addition, continental populations showed higher levels of differentiation and lower connectivity than peninsular populations in the absence of isolation by distance in each region. Some discrepancies with model expectations may relate to the influence of significant habitat discontinuities in the face of limited dispersal potential. Environmental data analyses and niche modeling allowed us to identify temperature, water clarity, and substrate availability as the main factors correlating with patterns of abundance, genetic diversity, and structure, which may hold the key to the survival of P. panamensis in the face of

  20. The effect of species and colony size on the bleaching response of reef-building corals in the Florida Keys during the 2005 mass bleaching event

    NASA Astrophysics Data System (ADS)

    Brandt, M. E.

    2009-12-01

    Understanding the variation in coral bleaching response is necessary for making accurate predictions of population changes and the future state of reefs in a climate of increasing thermal stress events. Individual coral colonies, belonging to inshore patch reef communities of the Florida Keys, were followed through the 2005 mass bleaching event. Overall, coral bleaching patterns followed an index of accumulated thermal stress more closely than in situ temperature measurements. Eight coral species ( Colpophyllia natans, Diploria strigosa, Montastraea cavernosa, M. faveolata, Porites astreoides, P. porites, Siderastrea siderea, and Stephanocoenia intersepta), representing >90% of the coral colonies studied, experienced intense levels of bleaching, but responses varied. Bleaching differed significantly among species: Colpophyllia natans and Diploria strigosa were most susceptible to thermal stress, while Stephanocoenia intersepta was the most tolerant. For colonies of C. natans, M. faveolata, and S. siderea, larger colonies experienced more extensive bleaching than smaller colonies. The inshore patch reef communities of the Florida Keys have historically been dominated by large colonies of Montastraea sp. and Colpophyllia natans. These results provide evidence that colony-level differences can affect bleaching susceptibility in this habitat and suggest that the impact of future thermal stress events may be biased toward larger colonies of dominant reef-building species. Predicted increases in the frequency of mass bleaching and subsequent mortality may therefore result in significant structural shifts of these ecologically important communities.

  1. Species-specific responses of corals to bleaching events on anthropogenically turbid reefs on Okinawa Island, Japan, over a 15-year period (1995-2009).

    PubMed

    Hongo, Chuki; Yamano, Hiroya

    2013-01-01

    Coral bleaching, triggered by elevated sea-surface temperatures (SSTs) has caused a decline in coral cover and changes in the abundances of corals on reefs worldwide. Coral decline can be exacerbated by the effects of local stressors like turbidity, yet some reefs with a natural history of turbidity can support healthy and resilient coral communities. However, little is known about responses of coral communities to bleaching events on anthropogenically turbid reefs as a result of recent (post World War II) terrestrial runoff. Analysis of region-scale coral cover and species abundance at 17-20 sites on the turbid reefs of Okinawa Island (total of 79 species, 30 genera, and 13 families) from 1995 to 2009 indicates that coral cover decreased drastically, from 24.4% to 7.5% (1.1%/year), subsequent to bleaching events in 1998 and 2001. This dramatic decrease in coral cover corresponded to the demise of Acropora species (e.g., A. digitifera) by 2009, when Acropora had mostly disappeared from turbid reefs on Okinawa Island. In contrast, Merulinidae species (e.g., Dipsastraea pallida/speciosa/favus) and Porites species (e.g., P. lutea/australiensis), which are characterized by tolerance to thermal stress, survived on turbid reefs of Okinawa Island throughout the period. Our results suggest that high turbidity, influenced by recent terrestrial runoff, could have caused a reduction in resilience of Acropora species to severe thermal stress events, because the corals could not have adapted to a relatively recent decline in water quality. The coral reef ecosystems of Okinawa Island will be severely impoverished if Acropora species fail to recover.

  2. Differential larval settlement responses of Porites astreoides and Acropora palmata in the presence of the green alga Halimeda opuntia

    NASA Astrophysics Data System (ADS)

    Olsen, K.; Sneed, J. M.; Paul, V. J.

    2016-06-01

    Settlement is critical to maintaining coral cover on reefs, yet interspecific responses of coral planulae to common benthic macroalgae are not well characterized. Larval survival and settlement of two Caribbean reef-building corals, the broadcast-spawner Acropora palmata and the planulae-brooder Porites astreoides, were quantified following exposure to plastic algae controls and the green macroalga Halimeda opuntia. Survival and settlement rates were not significantly affected by the presence of H. opuntia in either species. However, ~10 % of P. astreoides larvae settled on the surface of the macroalga, whereas larvae of A. palmata did not. It is unlikely that corals that settle on macroalgae will survive post-settlement; therefore, H. opuntia may reduce the number of P. astreoides and other non-discriminatory larvae that survive to adulthood. Our results suggest that the presence of macroalgae on impacted reefs can have unexpected repercussions for coral recruitment and highlight discrepancies in settlement specificity between corals with distinct life history strategies.

  3. Relative sensitivity of five Hawaiian coral species to high temperature under high-pCO2 conditions

    NASA Astrophysics Data System (ADS)

    Bahr, Keisha D.; Jokiel, Paul L.; Rodgers, Ku'ulei S.

    2016-06-01

    Coral reef ecosystems are presently undergoing decline due to anthropogenic climate change. The chief detrimental factors are increased temperature and increased pCO2. The purpose of this study was to evaluate the effect of these two stressors operating independently and in unison on the biological response of common Hawaiian reef corals. Manipulative experiments were performed using five species ( Porites compressa, Pocillopora damicornis, Fungia scutaria, Montipora capitata, and Leptastrea purpurea) in a continuous-flow mesocosm system under natural sunlight conditions. Corals were grown together as a community under treatments of high temperature (2 °C above normal maximum summer temperature), high pCO2 (twice present-day conditions), and with both factors acting in unison. Control corals were grown under present-day pCO2 and at normal summer temperatures. Leptastrea purpurea proved to be an extremely hardy coral. No change in calcification or mortality occurred under treatments of high temperature, high pCO2, or combined high temperature-high pCO2. The remaining four species showed reduced calcification in the high-temperature treatment. Two species ( L. purpurea and M. capitata) showed no response to increased pCO2. Also, high pCO2 ameliorated the negative effect of high temperature on the calcification rates of P. damicornis. Mortality was driven primarily by high temperature, with a negative synergistic effect in P. compressa only in the high-pCO2-high-temperature treatment. Results support the observation that biological response to temperature and pCO2 elevation is highly species-specific, so generalizations based on response of a single species might not apply to a diverse and complex coral reef community.

  4. Bacterial Acquisition in Juveniles of Several Broadcast Spawning Coral Species

    PubMed Central

    Sharp, Koty H.; Ritchie, Kim B.; Schupp, Peter J.; Ritson-Williams, Raphael; Paul, Valerie J.

    2010-01-01

    Coral animals harbor diverse microorganisms in their tissues, including archaea, bacteria, viruses, and zooxanthellae. The extent to which coral-bacterial associations are specific and the mechanisms for their maintenance across generations in the environment are unknown. The high diversity of bacteria in adult coral colonies has made it challenging to identify species-specific patterns. Localization of bacteria in gametes and larvae of corals presents an opportunity for determining when bacterial-coral associations are initiated and whether they are dynamic throughout early development. This study focuses on the early onset of bacterial associations in the mass spawning corals Montastraea annularis, M. franksi, M. faveolata, Acropora palmata, A. cervicornis, Diploria strigosa, and A. humilis. The presence of bacteria and timing of bacterial colonization was evaluated in gametes, swimming planulae, and newly settled polyps by fluorescence in situ hybridization (FISH) using general eubacterial probes and laser-scanning confocal microscopy. The coral species investigated in this study do not appear to transmit bacteria via their gametes, and bacteria are not detectable in or on the corals until after settlement and metamorphosis. This study suggests that mass-spawning corals do not acquire, or are not colonized by, detectable numbers of bacteria until after larval settlement and development of the juvenile polyp. This timing lays the groundwork for developing and testing new hypotheses regarding general regulatory mechanisms that control bacterial colonization and infection of corals, and how interactions among bacteria and juvenile polyps influence the structure of bacterial assemblages in corals. PMID:20526374

  5. Effects of fish predation and seaweed competition on the survival and growth of corals.

    PubMed

    Miller, Margaret W; Hay, Mark E

    1998-01-01

    On Caribbean coral reefs, high rates of grazing by herbivorous fishes are thought to benefit corals because fishes consume competing seaweeds. We conducted field experiments in the Florida Keys, USA, to examine the effects of grazing fishes on coral/seaweed competition. Initially, fragments of Porites divaracata from an inshore habitat were transplanted into full-cage, half-cage, and no-cage treatments on a fore-reef. Within 48 h, 56% of the unprotected corals in half-cage and no-cage treatments (62 of 111) were completely consumed. Stoplight parrotfish (Sparisoma viride) were the major coral predators, with redband parrotfish (S. aurofrenatum) also commonly attacking this coral. Next, we transplanted fragments of P. porites collected from the fore-reef habitat where our caging experiments were being conducted into the three cage treatments, half in the presence of transplanted seaweeds, and half onto initially clean substrates. The corals were allowed to grow in these conditions, with concurrent development of competing seaweeds, for 14 weeks. Although seaweed cover and biomass were both significantly greater in the full-cage treatment, coral growth did not differ significantly between cage treatments even though corals placed with pre-planted seaweeds grew significantly less than corals placed on initially clean substrate. This surprising result occurred because parrotfishes not only grazed algae from accessible treatments, but also fed directly on our coral transplants. Parrotfish feeding scars were significantly more abundant on P. porites from the half and no-cage treatments than on corals in the full cages. On this Florida reef, direct fish predation on some coral species (P. divaracata) can exclude them from fore-reef areas, as has previously been shown for certain seaweeds and sponges. For other corals that live on the fore-reef (P. porites), the benefits of fishes removing seaweeds can be counterbalanced by the detrimental effects of fishes directly

  6. Large-amplitude internal waves sustain coral health during thermal stress

    NASA Astrophysics Data System (ADS)

    Schmidt, Gertraud M.; Wall, Marlene; Taylor, Marc; Jantzen, Carin; Richter, Claudio

    2016-09-01

    Ocean warming is a major threat for coral reefs causing widespread coral bleaching and mortality. Potential refugia are thus crucial for coral survival. Exposure to large-amplitude internal waves (LAIW) mitigated heat stress and ensured coral survival and recovery during and after an extreme heat anomaly. The physiological status of two common corals, Porites lutea and Pocillopora meandrina, was monitored in host and symbiont traits, in response to LAIW-exposure throughout the unprecedented 2010 heat anomaly in the Andaman Sea. LAIW-exposed corals of both species survived and recovered, while LAIW-sheltered corals suffered partial and total mortality in P. lutea and P. meandrina, respectively. LAIW are ubiquitous in the tropics and potentially generate coral refuge areas. As thermal stress to corals is expected to increase in a warming ocean, the mechanisms linking coral bleaching to ocean dynamics will be crucial to predict coral survival on a warming planet.

  7. Does seaweed-coral competition make seaweeds more palatable?

    NASA Astrophysics Data System (ADS)

    Longo, G. O.; Hay, M. E.

    2015-03-01

    Seaweed-coral interactions are increasingly common on modern coral reefs, but the dynamics, processes, and mechanisms affecting these interactions are inadequately understood. We investigated the frequency and effect of seaweed-coral contacts for common seaweeds and corals in Belize. Effects on corals were evaluated by measuring the frequency and extent of bleaching when contacted by various seaweeds, and effects on a common seaweed were evaluated by assessing whether contact with coral made the seaweed more palatable to the sea urchin Diadema antillarum. Coral-seaweed contacts were particularly frequent between Agaricia corals and the seaweed Halimeda opuntia, with this interaction being associated with coral bleaching in 95 % of contacts. Pooling across all coral species, H. opuntia was the seaweed most commonly contacting corals and most frequently associated with localized bleaching at the point of contact. Articulated coralline algae, Halimeda tuna and Lobophora variegata also frequently contacted corals and were commonly associated with bleaching. The common corals Agaricia and Porites bleached with similar frequency when contacted by H. opuntia (95 and 90 %, respectively), but Agaricia experienced more damage than Porites when contacted by articulated coralline algae or H. tuna. When spatially paired individuals of H. opuntia that had been in contact with Agaricia and not in contact with any coral were collected from the reefs and offered to D. antillarum, urchins consumed about 150 % more of thalli that had been competing with Agaricia. Contact and non-contact thalli did not differ in nutritional traits (ash-free-dry-mass, C or N concentrations), suggesting that Halimeda chemical defenses may have been compromised by coral-algal contact. If competition with corals commonly enhances seaweed palatability, then the dynamics and nuances of small-scale seaweed-coral-herbivore interactions at coral edges are deserving of greater attention in that such

  8. Effects of herbivores, nutrient enrichment, and their interactions on macroalgal proliferation and coral growth

    NASA Astrophysics Data System (ADS)

    Sotka, E. E.; Hay, M. E.

    2009-09-01

    We conducted a 20-week manipulative field experiment on shallow forereefs of the Florida Keys to assess the separate and interactive effects of herbivory and nutrient enrichment on the development of macroalgal communities and the fitness of the corals Porites porites and Siderastrea siderea. Excluding large herbivorous fishes produced macrophyte blooms both with and without nutrient enrichment. In contrast, there were no direct effects of nutrient enrichment. There were, however, small, but significant, interactive effects of herbivory and enrichment on macroalgal cover. Following nutrient enrichment, total macroalgae and the common seaweeds Dictyota spp. were suppressed in the presence, but not in the absence, of large herbivorous fishes—suggesting that fishes were selectively feeding on nutrient-enriched macrophytes. Access by large herbivores prevented algal overgrowth of corals, but these large fishes also directly grazed both corals. Excluding fishes did not alter survivorship of either coral species, but did decrease parrotfish grazing scars on both corals and increased the net growth of P. porites. Nutrient additions had no direct effects on the survivorship of corals, but there was a trend ( P = 0.097) for nutrients to stimulate the growth of P. porites. The preponderance of experiments available to date indicates that loss of key herbivores is a major factor driving macroalgal blooms on coral reefs; anthropogenic nutrient pollution generally plays a more minor role.

  9. Internal bioerosion in dead and live hard corals in intertidal zone of Hormuz Island (Persian Gulf).

    PubMed

    Jafari, Mohammad Ali; Seyfabadi, Jafar; Shokri, Mohammad Reza

    2016-04-30

    Internal macrobioeroders and their erosion rate in three live and dead coral genera (Favia, Platygyra and Porites) from the intertidal zone of the Hormuz Island were studied by collecting five live and five dead colonies from each genus, from which 4 mm cross-sections were cut and photographed. Photos were analyzed using the Coral Point Count with Excel extensions. Totally, 9 taxa were identified: four bivalve species, one sponge, three polychaetes, and one barnacle. Bioerosion rate did not significantly differ among the three live corals, but among the dead ones only Porites was significantly more eroded than Favia. Sponge had the highest role in the erosion of the dead Platygyra, while barnacles were the most effective eroding organism in the live Platygyra. Polychaetes, followed by bivalves, were the most destructive bioeroders on the dead and live Porites. Further, none of the bioeroding organisms had selectively chosen either the dead or live Favia.

  10. Coral communities of the remote atoll reefs in the Nansha Islands, southern South China Sea.

    PubMed

    Zhao, M X; Yu, K F; Shi, Q; Chen, T R; Zhang, H L; Chen, T G

    2013-09-01

    During the months of May and June in the year 2007, a survey was conducted regarding coral reef communities in the remote atolls (Zhubi Reef and Meiji Reef) of Nansha Islands, southern South China Sea. The goals of the survey were to: (1) for the first time, compile a scleractinian coral check-list; (2) estimate the total richness, coral cover, and growth forms of the community; and (3) describe preliminary patterns of community structure according to geomorphological units. Findings of this survey revealed a total of 120 species of scleractinia belonging to 40 genera, while the average coral cover was 21 %, ranging from less than 10 % to higher than 50 %. Branching and massive corals were also found to be the most important growth forms of the whole coral community, while Acropora, Montipora, and Porites were the three dominant genera in the overall region, with their contributions to total coral cover measuring 21, 22, and 23 %, respectively. Overall, coral communities of the Nansha Islands were in a relative healthy condition with high species diversity and coral cover. Spatial pattern of coral communities existed among various geomorphological units. Mean coral cover was highest in the patch reef within the lagoon, followed by the fore reef slope, reef flat, and lagoon slope. The greatest contributors to total coral cover were branching Acropora (45 %) in the lagoon slope, branching Montipora (44 %) in the reef flat, and massive Porites (51 %) in the patch reef. Coral cover in the fore reef revealed a greater range of genera than in other habitats. The leeward fore reef slope had higher coral cover (> 50 %) when compared with the windward slope (< 10 %). The coral communities of the inner reef flat were characterized by higher coral cover (27 %) and dominant branching Montipora corals, while lower coral cover (4 %) was dominated by Psammocora with massive growth forms on the outer reef flat. Destructive fishing and coral bleaching were two major threats to

  11. Spatial patterns of parrotfish corallivory in the Caribbean: the importance of coral taxa, density and size.

    PubMed

    Roff, George; Ledlie, Mary H; Ortiz, Juan C; Mumby, Peter J

    2011-01-01

    The past few decades have seen an increase in the frequency and intensity of disturbance on coral reefs, resulting in shifts in size and composition of coral populations. These changes have lead to a renewed focus on processes that influence demographic rates in corals, such as corallivory. While previous research indicates selective corallivory among coral taxa, the importance of coral size and the density of coral colonies in influencing corallivory are unknown. We surveyed the size, taxonomy and number of bites by parrotfish per colony of corals and the abundance of three main corallivorous parrotfish (Sparisoma viride, Sparisoma aurofrenatum, Scarus vetula) at multiple spatial scales (reefs within islands: 1-100 km, and between islands: >100 km) within the Bahamas Archipelago. We used a linear mixed model to determine the influence of coral taxa, colony size, colony density, and parrotfish abundance on the intensity of corallivory (bites per m(2) of coral tissue). While the effect of colony density was significant in determining the intensity of corallivory, we found no significant influence of colony size or parrotfish abundance (density, biomass or community structure). Parrotfish bites were most frequently observed on the dominant species of reef building corals (Montastraea annularis, Montastraea faveolata and Porites astreoides), yet our results indicate that when the confounding effects of colony density and size were removed, selective corallivory existed only for the less dominant Porites porites. As changes in disturbance regimes result in the decline of dominant frame-work building corals such as Montastraea spp., the projected success of P. porites on Caribbean reefs through high reproductive output, resistance to disease and rapid growth rates may be attenuated through selective corallivory by parrotfish.

  12. Identification and prevalence of coral diseases on three Western Indian Ocean coral reefs.

    PubMed

    Séré, Mathieu G; Chabanet, Pascale; Turquet, Jean; Quod, Jean-Pascal; Schleyer, Michael H

    2015-06-03

    Coral diseases have caused a substantial decline in the biodiversity and abundance of reef-building corals. To date, more than 30 distinct diseases of scleractinian corals have been reported, which cause progressive tissue loss and/or affect coral growth, reproductive capacity, recruitment, species diversity and the abundance of reef-associated organisms. While coral disease research has increased over the last 4 decades, very little is known about coral diseases in the Western Indian Ocean. Surveys conducted at multiple sites in Reunion, South Africa and Mayotte between August 2010 and June 2012 revealed the presence of 6 main coral diseases: black band disease (BBD), white syndrome (WS), pink line syndrome (PLS), growth anomalies (GA), skeleton eroding band (SEB) and Porites white patch syndrome (PWPS). Overall, disease prevalence was higher in Reunion (7.5 ± 2.2%; mean ± SE) compared to South Africa (3.9 ± 0.8%) and Mayotte (2.7 ± 0.3%). Across locations, Acropora and Porites were the genera most susceptible to disease. Spatial variability was detected in both Reunion and South Africa, with BBD and WS more prevalent on shallow than deep reefs. There was also evidence of seasonality in 2 diseases: the prevalence of BBD and WS was higher in summer than winter. This was the first study to investigate the ecology of coral diseases, providing both qualitative and quantitative data, on Western Indian Ocean reefs, and surveys should be expanded to confirm these patterns.

  13. Molecular delineation of species in the coral holobiont.

    PubMed

    Stat, Michael; Baker, Andrew C; Bourne, David G; Correa, Adrienne M S; Forsman, Zac; Huggett, Megan J; Pochon, Xavier; Skillings, Derek; Toonen, Robert J; van Oppen, Madeleine J H; Gates, Ruth D

    2012-01-01

    The coral holobiont is a complex assemblage of organisms spanning a diverse taxonomic range including a cnidarian host, as well as various dinoflagellate, prokaryotic and acellular symbionts. With the accumulating information on the molecular diversity of these groups, binomial species classification and a reassessment of species boundaries for the partners in the coral holobiont is a logical extension of this work and will help enhance the capacity for comparative research among studies. To aid in this endeavour, we review the current literature on species diversity for the three best studied partners of the coral holobiont (coral, Symbiodinium, prokaryotes) and provide suggestions for future work on systematics within these taxa. We advocate for an integrative approach to the delineation of species using both molecular genetics in combination with phenetic characters. We also suggest that an a priori set of criteria be developed for each taxonomic group as no one species concept or accompanying set of guidelines is appropriate for delineating all members of the coral holobiont.

  14. Sibling species in Montastraea annularis, coral bleaching, and the coral climate record

    SciTech Connect

    Knowlton, N.; Weil, E.; Weigt, L.A.; Guzman, H.M. )

    1992-01-17

    Measures of growth and skeletal isotopic ratios in the Caribbean coral Montastraea annularis are fundamental to many studies of paleoceanography, environmental degradation, and global climate change. This taxon is shown to consist of at least three sibling species in shallow water. The two most commonly studied of these show highly significant differences in growth rate and oxygen isotopic ratios, parameters routinely used to estimate past climatic conditions; unusual coloration in the third may have confused research on coral bleaching. Interpretation or comparison of past and current studies can be jeopardized by ignoring these species boundaries.

  15. 77 FR 30261 - Petition To List 83 Species of Coral as Threatened or Endangered Under the Endangered Species Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-22

    ... National Oceanic and Atmospheric Administration RIN 0648-XT12 Petition To List 83 Species of Coral as... 82 coral species in response to a petition from the Center for Biological Diversity (CBD) to list 83 coral species as threatened or endangered under the Endangered Species Act (ESA). The purposes of...

  16. 77 FR 22749 - Petition To List 83 Species of Coral as Threatened or Endangered Under the Endangered Species Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-17

    ... Species of Coral as Threatened or Endangered Under the Endangered Species Act (ESA) AGENCY: National... for Biological Diversity (CBD) to list 83 coral species as threatened or endangered under the... of 82 coral species, while the draft Management Report describes existing regulatory mechanisms...

  17. detrimentally affects tissue regeneration of Red Sea corals

    NASA Astrophysics Data System (ADS)

    Horwitz, Rael; Fine, Maoz

    2014-09-01

    Ocean acidification (OA) from rising atmospheric carbon dioxide (CO2) is threatening the future of coral reef ecosystems. Mounting experimental evidence suggests that OA negatively impacts fundamental life functions of scleractinian corals, including growth and sexual reproduction. Although regeneration is regarded as a chief life function in scleractinian corals and essential to maintain the colony's integrity, the effect of OA on regeneration processes has not yet been investigated. To evaluate the effects of OA on regeneration, the common Indo-Pacific corals Porites sp., Favia favus, Acropora eurystoma, and Stylophora pistillata were inflicted with lesions (314-350 mm2, depending on species) and incubated in different pCO2: (1) ambient seawater (400 µatm, pH 8.1), (2) intermediate (1,800 µatm, pH 7.6), and (3) high (4,000 µatm, pH 7.3) for extended periods of time (60-120 d). While all coral species after 60 d had significantly higher tissue regeneration in ambient conditions as compared to the intermediate and high treatments, reduction in regeneration rate was more pronounced in the slow-growing massive Porites sp. and F. favus than the relatively fast-growing, branching S. pistillata and A. eurystoma. This coincided with reduced tissue biomass of Porites sp., F. favus, and A. eurystoma in higher pCO2, but not in S. pistillata. Porites sp., F. favus, and S. pistillata also experienced a decrease in Symbiodinium density in higher pCO2, while in A. eurystoma there was no change. We hypothesize that a lowered regenerative capacity under elevated pCO2 may be related to resource trade-offs, energy cost of acid/base regulation, and/or decrease in total energy budget. This is the first study to demonstrate that elevated pCO2 could have a compounding influence on coral regeneration following injury, potentially affecting the capacity of reef corals to recover following physical disturbance.

  18. Transplantation of storm-generated coral fragments to enhance Caribbean coral reefs: A successful method but not a solution

    USGS Publications Warehouse

    Garrison, V.H.; Ward, G.

    2012-01-01

    In response to dramatic losses of reef-building corals and ongoing lack of recovery, a small-scale coral transplant project was initiated in the Caribbean (U.S. Virgin Islands) in 1999 and was followed for 12 years. The primary objectives were to (1) identify a source of coral colonies for transplantation that would not result in damage to reefs, (2) test the feasibility of transplanting storm-generated coral fragments, and (3) develop a simple, inexpensive method for transplanting fragments that could be conducted by the local community. The ultimate goal was to enhance abundance of threatened reef-building species on local reefs. Storm-produced coral fragments of two threatened reef-building species [Acropora palmata and A. cervicornis (Acroporidae)] and another fast-growing species [Porites porites (Poritidae)] were collected from environments hostile to coral fragment survival and transplanted to degraded reefs. Inert nylon cable ties were used to attach transplanted coral fragments to dead coral substrate. Survival of 75 reference colonies and 60 transplants was assessed over 12 years. Only 9% of colonies were alive after 12 years: no A. cervicornis; 3% of A. palmata transplants and 18% of reference colonies; and 13% of P. porites transplants and 7% of reference colonies. Mortality rates for all species were high and were similar for transplant and reference colonies. Physical dislodgement resulted in the loss of 56% of colonies, whereas 35% died in place. Only A. palmata showed a difference between transplant and reference colony survival and that was in the first year only. Location was a factor in survival only for A. palmata reference colonies and after year 10. Even though the tested methods and concepts were proven effective in the field over the 12-year study, they do not present a solution. No coral conservation strategy will be effective until underlying intrinsic and/or extrinsic factors driving high mortality rates are understood and mitigated or

  19. A novel method for the transport and analysis of genetic material from polyps and zooxanthellae of scleractinian corals.

    PubMed

    Crabbe, M James C

    2003-08-29

    We have developed a new simple method for transport, storage, and analysis of genetic material from the corals Agaricia agaricites, Dendrogyra cylindrica, Eusmilia ancora, Meandrina meandrites, Montastrea annularis, Porites astreoides, Porites furcata, Porites porites, and Siderastrea siderea at room temperature. All species yielded sufficient DNA from a single FTA card (19 microg-43 ng) for subsequent PCR amplification of both coral and zooxanthellar DNA. The D1 and D2 variable region of the large subunit rRNA gene (LSUrDNA) was amplified from the DNA of P. furcata and S. siderea by PCR. Electrophoresis yielded two major DNA bands: an 800-base pair (bp) DNA, which represented the coral ribosomal RNA (rRNA) gene, and a 600-bp DNA, which represented the zooxanthellar srRNA gene. Extraction of DNA from the bands yielded between 290 microg total DNA (S. siderea coral DNA) and 9 microg total DNA (P. furcata zooxanthellar DNA). The ability to transport and store genetic material from scleractinian corals without resort to laboratory facilities in the field allows for the molecular study of a far wider range and variety of coral sites than have been studied to date.

  20. Microbial aggregates within tissues infect a diversity of corals throughout the Indo-Pacific

    USGS Publications Warehouse

    Work, Thierry M.; Aeby, Greta S.

    2014-01-01

    Coral reefs are highly diverse ecosystems where symbioses play a pivotal role. Corals contain cell-associated microbial aggregates (CAMA), yet little is known about how widespread they are among coral species or the nature of the symbiotic relationship. Using histology, we found CAMA within 24 species of corals from 6 genera from Hawaii, American Samoa, Palmyra, Johnston Atoll, Guam, and Australia. Prevalence (%) of infection varied among coral genera: Acropora, Porites, and Pocillopora were commonly infected whereas Montipora were not. Acropora from the Western Pacific were significantly more likely to be infected with CAMA than those from the Central Pacific, whereas the reverse was true for Porites. Compared with apparently healthy colonies, tissues from diseased colonies were significantly more likely to have both surface and basal body walls infected. The close association of CAMA with host cells in numerous species of apparently healthy corals and lack of associated cell pathology reveals an intimate agent-host association. Furthermore, CAMA are Gram negative and in some corals may be related to chlamydia or rickettsia. We propose that CAMA in adult corals are facultative secondary symbionts that could play an important ecological role in some dominant coral genera in the Indo-Pacific. CAMA are important in the life histories of other animals, and more work is needed to understand their role in the distribution, evolution, physiology, and immunology of reef corals.

  1. Seasonally resolved sea surface temperature variability over the past 435 years in the northwestern Pacific recorded in Porites coral in Kikai Island, Southern Japan

    NASA Astrophysics Data System (ADS)

    Kawakubo, Y.; Yokoyama, Y.; Suzuki, A.; Alibert, C.; Kinsley, L.; Eggins, S. M.

    2011-12-01

    The Little Ice Age (LIA) is the most recent climate anomaly. According to the hemispheric scale surface temperature reconstructions based on the proxy records in various places, LIA is characterized by the cooling period between 1400 and 1850. However, since these proxy records mainly depend on the terrestrial records in mid to high latitude in the northern hemisphere and the marine records are limited, there is still no consensus concerning its spatial pattern, timing and cause. In June 2009, we obtained a 435-year-long modern core from a coral reef in Kikai Island, Japan. The island is located on the eastern boundary of the East China Sea in the northwestern Pacific. This modern coral core can date back to the LIA. Thus, to better understand the LIA, we reconstructed seasonally resolved sea surface temperature (SST) over the past 435 years in the northwestern Pacific, where it is a lack of records during LIA, based on Sr/Ca ratio in coral skeleton in Kikai Island. We analyzed the skeletal elements using laser ablation inductively coupled plasma mass spectorometry (LA-ICP-MS). This is a very powerful tool to handle long-term records since it requires a relatively brief experimental time compared with the analysis using isotope dilution or thermal ionazation ICP-MS. Our SST reconstruction in Kikai Island during LIA showed cooler period before 1700 and a bit warmer period between 1700 and 1850 compared with the average after the LIA. Based on these results, we discuss the paleoceanographic conditions in the northwestern Pacific during the LIA.

  2. Temporal variations of heavy metals in coral Porites lutea from Guangdong Province, China: Influences from industrial pollution, climate and economic factors

    USGS Publications Warehouse

    Peng, Z.; Liu, J.; Zhou, C.; Nie, B.; Chen, T.

    2006-01-01

    The correlation coefficients among the metals and climatic and economic factors indicate that the metals Ni, Zn, and Cd behave similarly. Copper and Mn are positively correlated, and cobalt is negatively correlated with Cr, Ni, Zn, and Cd. Lead is not correlated with any other metals but is correlated with sea surface water temperature, air temperature, GDP and industrial-agricultural production in Dianbai County. Lead in corals is related to the enhanced pollution level of ocean waters as a result of increased industrial activities.

  3. Aggregation and cnidae development as early defensive strategies in Favia fragum and Porites astreoides

    NASA Astrophysics Data System (ADS)

    Rivera, H. E.; Goodbody-Gringley, G.

    2014-12-01

    To survive, corals possess a variety of active and passive defenses. This study examined the effectiveness of aggregation and cnidae development as defensive strategies in enhancing post-settlement survival and growth of two brooding corals, Favia fragum and Porites astreoides, in Bermuda. Growth and survival of solitary and aggregated spat were monitored over seven weeks; cnidae were extracted from surviving spat. F. fragum aggregated spat had higher mortality, slower growth, and more cnidae than solitary spat. On the other hand, aggregation proved beneficial for P. astreoides spat, which had significantly lower mortality, faster growth, and fewer cnidae. Aggregated and solitary F. fragum spat displayed negative correlations between cnidae density and growth, suggesting a trade-off between defense and growth; however, P. astreoides spat did not demonstrate such a trade-off. These differing responses suggest that early patterns of survivorship and defensive strategies are highly species specific and complex.

  4. 78 FR 12702 - Endangered and Threatened Species; Proposed Rule To List 66 Reef-Building Coral Species; Proposed...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-25

    ... Threatened Species; Proposed Rule To List 66 Reef- Building Coral Species; Proposed Reclassification of... listing determinations of 66 reef-building coral species and the proposed reclassifications of elkhorn (Acropora palmata) and staghorn (Acropora cervicornis) corals under the ESA until April 6, 2013,...

  5. The functional gene composition and metabolic potential of coral-associated microbial communities

    PubMed Central

    Zhang, Yanying; Ling, Juan; Yang, Qingsong; Wen, Chongqing; Yan, Qingyun; Sun, Hongyan; Van Nostrand, Joy D.; Shi, Zhou; Zhou, Jizhong; Dong, Junde

    2015-01-01

    The phylogenetic diversity of coral-associated microbes has been extensively examined, but some contention remains regarding whether coral-associated microbial communities are species-specific or site-specific. It is suggested that corals may associate with microbes in terms of function, although little is known about the differences in coral-associated microbial functional gene composition and metabolic potential among coral species. Here, 16S rRNA Illumina sequencing and functional gene array (GeoChip 5.0) were used to assess coral-associated microbial communities. Our results indicate that both host species and environmental variables significantly correlate with shifts in the microbial community structure and functional potential. Functional genes related to key biogeochemical cycles including carbon, nitrogen, sulfur and phosphorus cycling, metal homeostasis, organic remediation, antibiotic resistance and secondary metabolism were shown to significantly vary between and among the four study corals (Galaxea astreata, Porites lutea, Porites andrewsi and Pavona decussata). Genes specific for anammox were also detected for the first time in the coral holobiont and positively correlated with ammonium. This study reveals that variability in the functional potential of coral-associated microbial communities is largely driven by changes in environmental factors and further demonstrates the importance of linking environmental parameters with genomic data in complex environmental systems. PMID:26536917

  6. Spatial refugia mediate juvenile coral survival during coral-predator interactions

    NASA Astrophysics Data System (ADS)

    Gallagher, Clare; Doropoulos, Christopher

    2017-03-01

    Coral recruitment and juvenile growth are essential processes for coral population maintenance and recovery. A growing body of research has evaluated the influence of reef microstructure on coral settlement and post-settlement survival, showing that physical refugia enhance recruitment. These studies have evaluated coral recruit morality from competition with macroalgae and indirect predation by grazing organisms, but the impact of direct predation by corallivorous piscine species on juvenile corals and how this interacts with reef microstructure is relatively unknown. This study examined whether refugia provided by micro-crevices enhance juvenile coral survival from corallivory. Juvenile corals from two different functional groups, the slow-growing massive Porites lobata and fast-growing branching Pocillopora damicornis, with average nubbin sizes of 1.4 cm × 0.3 cm and 0.5 cm × 1.0 cm (diameter × height), respectively, were attached to experimental tiles using small (1.44 cm3) and large (8.0 cm3) crevice sizes and were monitored for 29 d on a forereef in Palau. Full crevices (four sided) enhanced coral survival compared to exposed microhabitats in both coral taxa, but crevice size did not alter survival rates. Corallivores targeted recruits within crevices regardless of crevice size; dominant predators included small triggerfish (Balistidae), butterflyfish ( Chaetodon), and wrasse ( Cheilinus). Overall, Pocillopora suffered much higher rates of mortality than Porites. All Pocillopora were consumed by day 8 of the experiment, but mortality was significantly delayed in full crevices compared to exposed and partial crevice (three sided) microhabitats. In contrast, Por. lobata located in all microhabitats survived the entire experiment up to 29 d, with high survival in full (>90%) and partial crevices (70%), but only 28% survival in exposed microhabitats. These findings show the importance of crevices as spatial refugia from predators for juvenile corals and

  7. Competitive interactions between corals and turf algae depend on coral colony form.

    PubMed

    Swierts, Thomas; Vermeij, Mark Ja

    2016-01-01

    Turf algae are becoming more abundant on coral reefs worldwide, but their effects on other benthic organisms remain poorly described. To describe the general characteristics of competitive interactions between corals and turf algae, we determined the occurrence and outcomes of coral-turf algal interactions among different coral growth forms (branching, upright, massive, encrusting, plating, and solitary) on a shallow reef in Vietnam. In total, the amount of turf algal interaction, i.e., the proportion of the coral boundary directly bordering turf algae, was quantified for 1,276 coral colonies belonging to 27 genera and the putative outcome of each interaction was noted. The amount of turf algal interaction and the outcome of these interactions differed predictably among the six growth forms. Encrusting corals interacted most often with turf algae, but also competed most successfully against turf algae. The opposite was observed for branching corals, which rarely interacted with turf algae and rarely won these competitive interactions. Including all other growth forms, a positive relationship was found between the amount of competitive interactions with neighboring turf algae and the percentage of such interaction won by the coral. This growth form dependent ability to outcompete turf algae was not only observed among coral species, but also among different growth forms in morphologically plastic coral genera (Acropora, Favia, Favites, Montastrea, Montipora, Porites) illustrating the general nature of this relationship.

  8. Soft Coral Sarcophyton (Cnidaria: Anthozoa: Octocorallia) Species Diversity and Chemotypes

    PubMed Central

    Aratake, Satoe; Tomura, Tomohiko; Saitoh, Seikoh; Yokokura, Ryouma; Kawanishi, Yuichi; Shinjo, Ryuichi; Reimer, James Davis; Tanaka, Junichi; Maekawa, Hideaki

    2012-01-01

    Research on the soft coral genus Sarcophyton extends over a wide range of fields, including marine natural products and the isolation of a number of cembranoid diterpenes. However, it is still unknown how soft corals produce this diverse array of metabolites, and the relationship between soft coral diversity and cembranoid diterpene production is not clear. In order to understand this relationship, we examined Sarcophyton specimens from Okinawa, Japan, by utilizing three methods: morphological examination of sclerites, chemotype identification, and phylogenetic examination of both Sarcophyton (utilizing mitochondrial protein-coding genes MutS homolog: msh1) and their endosymbiotic Symbiodinium spp. (utilizing nuclear internal transcribed spacer of ribosomal DNA: ITS- rDNA). Chemotypes, molecular phylogenetic clades, and sclerites of Sarcophyton trocheliophorum specimens formed a clear and distinct group, but the relationships between chemotypes, molecular phylogenetic clade types and sclerites of the most common species, Sarcophyton glaucum, was not clear. S. glaucum was divided into four clades. A characteristic chemotype was observed within one phylogenetic clade of S. glaucum. Identities of symbiotic algae Symbiodinium spp. had no apparent relation to chemotypes of Sarcophyton spp. This study demonstrates that the complex results observed for S. glaucum are due to the incomplete and complex taxonomy of this species group. Our novel method of identification should help contribute to classification and taxonomic reassessment of this diverse soft coral genus. PMID:22272344

  9. Physiological and ecological performance differs in four coral taxa at a volcanic carbon dioxide seep.

    PubMed

    Strahl, J; Stolz, I; Uthicke, S; Vogel, N; Noonan, S H C; Fabricius, K E

    2015-06-01

    Around volcanic carbon dioxide (CO2) seeps in Papua New Guinea, partial pressures of CO2 (pCO2) approximate those as predicted for the end of this century, and coral communities have low diversity and low structural complexity. To assess the mechanisms for such community shifts in response to ocean acidification, we examined the physiological performance of two hard corals that occur with increased or unaltered abundance at a seep site (mean pHTotal=7.8, pCO2=862 μatm) compared to a control site (mean pHTotal=8.1, pCO2=323 μatm), namely massive Porites spp. and Pocillopora damicornis, and two species with reduced abundance, Acropora millepora and Seriatopora hystrix. Oxygen fluxes, calcification, and skeletal densities were analyzed in corals originating from the seep and control site. Net photosynthesis rates increased considerably in Porites spp. and A. millepora and slightly in P. damicornis at increased pCO2, but remained unaltered in S. hystrix. Dark respiration rates remained constant in all corals investigated from both sites. Rates of light calcification declined in S. hystrix at high pCO2, but were unaffected by pCO2 in the other three coral taxa. Dark and net calcification rates remained unchanged in massive Porites and P. damicornis, but were drastically reduced at high pCO2 in A. millepora and S. hystrix. However, skeletal densities were similar at both seep and control sites in all coral taxa investigated. Our data suggest that the pCO2-tolerant corals were characterized by an increased ability to acclimatize to ocean acidification, e.g. by maintaining net calcification. Thus, robust corals, such as Porites spp. and P. damicornis, are more likely to persist for longer in a future high pCO2 world than those unable to acclimatize.

  10. Increased light intensity induces heat shock protein Hsp60 in coral species.

    PubMed

    Chow, Ari M; Ferrier-Pagès, Christine; Khalouei, Sam; Reynaud, Stéphanie; Brown, Ian R

    2009-09-01

    The effect of increased light intensity and heat stress on heat shock protein Hsp60 was examined in two coral species using a branched coral and a laminar coral, selected for their different resistance to environmental perturbation. Transient Hsp60 induction was observed in the laminar coral following either light or thermal stress. Sustained induction was observed when these stresses were combined. The branched coral exhibited comparatively weak transient Hsp60 induction after heat stress and no detectable induction following light stress, consistent with its susceptibility to bleaching in native environments compared to the laminar coral. Our observations also demonstrate that increased light intensity and heat stress exhibited a greater negative impact on the photosynthetic capacity of environmentally sensitive branched coral than the more resistant laminar coral. This supports a correlation between stress induction of Hsp60 and (a) ability to counter perturbation of photosynthetic capacity by light and heat stress and (b) resistance to environmentally induced coral bleaching.

  11. Herbivory versus corallivory: are parrotfish good or bad for Caribbean coral reefs?

    NASA Astrophysics Data System (ADS)

    Mumby, Peter J.

    2009-09-01

    With coral cover in decline on many Caribbean reefs, any process of coral mortality is of potential concern. While sparisomid parrotfishes are major grazers of Caribbean reefs and help control algal blooms, the fact that they also undertake corallivory has prompted some to question the rationale for their conservation. Here the weight of evidence for beneficial effects of parrotfishes, in terms of reducing algal cover and facilitating demographic processes in corals, and the deleterious effects of parrotfishes in terms of causing coral mortality and chronic stress, are reviewed. While elevated parrotfish density will likely increase the predation rate upon juvenile corals, the net effect appears to be positive in enhancing coral recruitment through removal of macroalgal competitors. Parrotfish corallivory can cause modest partial colony mortality in the most intensively grazed species of Montastraea but the generation and healing of bite scars appear to be in near equilibrium, even when coral cover is low. Whole colony mortality in adult corals can lead to complete exclusion of some delicate, lagoonal species of Porites from forereef environments but is only reported for one reef species ( Porites astreoides), for one habitat (backreef), and with uncertain incidence (though likely <<10%). No deleterious effects of predation on coral growth or fecundity have been reported, though recovery of zooxanthellae after bleaching events may be retarded. The balance of evidence to date finds strong support for the herbivory role of parrotfishes in facilitating coral recruitment, growth, and fecundity. In contrast, no net deleterious effects of corallivory have been reported for reef corals. Corallivory is unlikely to constrain overall coral cover but contraints upon dwindling populations of the Montastraea annularis species complex are feasible and the role of parrotfishes as a vector of coral disease requires evaluation. However, any assertion that conservation practices

  12. Competitive interactions between corals and turf algae depend on coral colony form

    PubMed Central

    Vermeij, Mark JA

    2016-01-01

    Turf algae are becoming more abundant on coral reefs worldwide, but their effects on other benthic organisms remain poorly described. To describe the general characteristics of competitive interactions between corals and turf algae, we determined the occurrence and outcomes of coral–turf algal interactions among different coral growth forms (branching, upright, massive, encrusting, plating, and solitary) on a shallow reef in Vietnam. In total, the amount of turf algal interaction, i.e., the proportion of the coral boundary directly bordering turf algae, was quantified for 1,276 coral colonies belonging to 27 genera and the putative outcome of each interaction was noted. The amount of turf algal interaction and the outcome of these interactions differed predictably among the six growth forms. Encrusting corals interacted most often with turf algae, but also competed most successfully against turf algae. The opposite was observed for branching corals, which rarely interacted with turf algae and rarely won these competitive interactions. Including all other growth forms, a positive relationship was found between the amount of competitive interactions with neighboring turf algae and the percentage of such interaction won by the coral. This growth form dependent ability to outcompete turf algae was not only observed among coral species, but also among different growth forms in morphologically plastic coral genera (Acropora, Favia, Favites, Montastrea, Montipora, Porites) illustrating the general nature of this relationship. PMID:27190707

  13. Mine waste disposal leads to lower coral cover, reduced species richness and a predominance of simple coral growth forms on a fringing coral reef in Papua New Guinea.

    PubMed

    Haywood, M D E; Dennis, D; Thomson, D P; Pillans, R D

    2016-04-01

    A large gold mine has been operating at the Lihir Island Group, Papua New Guinea since 1997. The mine disposes of waste rock in nearshore waters, impacting nearby coral communities. During 2010, 2012 we conducted photographic surveys at 73 sites within 40 km of the mine to document impacts of mining operations on the hard coral communities. Coral communities close to the mine (∼2 km to the north and south of the mine) were depaurperate, but surprisingly, coral cover and community composition beyond this range appeared to be relatively similar, suggesting that the mine impacts were limited spatially. In particular, we found mining operations have resulted in a significant decrease in coral cover (4.4% 1.48 km from the disposal site c.f. 66.9% 10.36 km from the disposal site), decreased species richness and a predominance of less complex growth forms within ∼2 km to the north and south of the mine waste disposal site. In contrast to the two 'snapshot' surveys of corals performed in 2010 and 2012, long term data (1999-2012) based on visual estimates of coral cover suggested that impacts on coral communities may have been more extensive than this. With global pressures on the world's coral reefs increasing, it is vital that local, direct anthropogenic pressures are reduced, in order to help offset the impacts of climate change, disease and predation.

  14. Bacterial communities and species-specific associations with the mucus of Brazilian coral species

    PubMed Central

    Carlos, Camila; Torres, Tatiana T.; Ottoboni, Laura M. M.

    2013-01-01

    We investigated the existence of species-specific associations between Brazilian coral species and bacteria. Pyrosequencing of the V3 region of the 16S rDNA was used to analyze the taxonomic composition of bacterial communities associated with the mucus of four coral species (Madracis decactis, Mussismilia hispida, Palythoa caribaeorum, and Tubastraea coccinea) in two seasons (winter and summer), which were compared with the surrounding water and sediment. The microbial communities found in samples of mucus, water, and sediment differed according to the composition and relative frequency of OTUs. The coral mucus community seemed to be more stable and resistant to seasonal variations, compared to the water and sediment communities. There was no influence of geographic location on the composition of the communities. The sediment community was extremely diverse and might act as a "seed bank" for the entire environment. Species-specific OTUs were found in P. caribaeorum, T. coccinea, and M. hispida. PMID:23567936

  15. Predicting coral species richness: the effect of input variables, diversity and scale.

    PubMed

    Richards, Zoe T; Hobbs, Jean-Paul A

    2014-01-01

    Coral reefs are facing a biodiversity crisis due to increasing human impacts, consequently, one third of reef-building corals have an elevated risk of extinction. Logistic challenges prevent broad-scale species-level monitoring of hard corals; hence it has become critical that effective proxy indicators of species richness are established. This study tests how accurately three potential proxy indicators (generic richness on belt transects, generic richness on point-intercept transects and percent live hard coral cover on point-intercept transects) predict coral species richness at three different locations and two analytical scales. Generic richness (measured on a belt transect) was found to be the most effective predictor variable, with significant positive linear relationships across locations and scales. Percent live hard coral cover consistently performed poorly as an indicator of coral species richness. This study advances the practical framework for optimizing coral reef monitoring programs and empirically demonstrates that generic richness offers an effective way to predict coral species richness with a moderate level of precision. While the accuracy of species richness estimates will decrease in communities dominated by species-rich genera (e.g. Acropora), generic richness provides a useful measure of phylogenetic diversity and incorporating this metric into monitoring programs will increase the likelihood that changes in coral species diversity can be detected.

  16. Implications of coral harvest and transplantation on reefs in northwestern Dominica.

    PubMed

    Bruckner, Andrew W; Borneman, Eric H

    2010-10-01

    In June, 2002, the government of Dominica requested assistance in evaluating the coral culture and transplantation activities being undertaken by Oceanographic Institute of Dominica (OID), a coral farm culturing both western Atlantic and Indo-Pacific corals for restoration and commercial sales. We assessed the culture facilities of OID, the condition of reefs, potential impacts of coral collection and benefits of coral transplantation. Coral reefs (9 reefs, 3-20 m depth) were characterized by 35 species of scleractinian corals and a live coral cover of 8-35%. Early colonizing, brooders such as Porites astreoides (14.8% of all corals), P. porites (14.8%), Meandrina meandrites (14.7%) and Agaricia agaricites (9.1%) were the most abundant corals, but colonies were mostly small (mean = 25 cm diameter). Montastraea annularis (complex) was the other dominant taxa (20.8% of all corals) and colonies were larger (mean = 70 cm). Corals (pooled species) were missing an average of 20% of their tissue, with a mean of 1.4% recent mortality. Coral diseases affected 6.4% of all colonies, with the highest prevalence at Cabrits West (11.0%), Douglas Bay (12.2%) and Coconut Outer reef (20.7%). White plague and yellow band disease were causing the greatest loss of tissue, especially among M. annularis (complex), with localized impacts from corallivores, overgrowth by macroalgae, storm damage and sedimentation. While the reefs appeared to be undergoing substantial decline, restoration efforts by OlD were unlikely to promote recovery. No Pacific species were identified at OID restoration sites, yet species chosen for transplantation with highest survival included short-lived brooders (Agaricia and Porites) that were abundant in restoration sites, as well as non-reef builders (Palythoa and Erythropodium) that monopolize substrates and overgrow corals. The species of highest value for restoration (massive broadcast spawners) showed low survivorship and unrestored populations of these

  17. Species-diverse coral communities on an artificial substrate at a tuna farm in Amami, Japan.

    PubMed

    Hata, Hiroki; Hirabayashi, Isao; Hamaoka, Hideki; Mukai, Yoshio; Omori, Koji; Fukami, Hironobu

    2013-04-01

    Tuna-farming is expanding worldwide, necessitating the monitoring/managing of its effects on the natural environment. In Japan, tuna-farming is conducted on coral reefs that have been damaged by mass-bleaching events and crown-of-thorns starfish (COTS) outbreaks. This study focused on the coral community on an artificial substrate of tuna-farm to reveal the possible effects of tuna-farming on the natural environment. Corals flourished on ropes suspended in the farm in the Amami Islands, southern Japan. These were moored 3 m below the sea-surface in 50-m-deep water. The coral community on the rope was analyzed and compared with those on natural substrata on two adjacent COTS-damaged reefs and with that in a protected reef. Corals were monitored throughout a year. Sixty coral species grew on the ropes, that corresponds to 27.3% of the 220 species known from Amami. The coral community was unique, dominated by massive faviid corals. On the ropes, the water temperature rarely exceeded 30.0 °C and no corals on the rope were severely bleached or covered by sedimentation during the observations. The tuna-farm infrastructure provided corals with a suitable habitat, and species-rich coral communities were established. These coral communities are an important node connecting tuna-farms and the natural environment.

  18. Among-species variation in the energy budgets of reef-building corals: scaling from coral polyps to communities.

    PubMed

    Hoogenboom, Mia; Rottier, Cécile; Sikorski, Severine; Ferrier-Pagès, Christine

    2015-12-01

    The symbiosis between corals and dinoflagellates promotes the rapid growth of corals in shallow tropical oceans, and the high overall productivity of coral reefs. The aim of this study was to quantify and understand variation in carbon acquisition and allocation among coral species. We measured multiple physiological traits (including symbiont density, calcification, photosynthesis and tissue composition) for the same coral fragments to facilitate direct comparisons between species (Stylophora pistillata, Pocillopora damicornis, Galaxea fascicularis, Turbinaria reniformis and Acropora sp.). Tissue protein content was highly sensitive to the availability of particulate food, increasing in fed colonies of all species. Despite among-species variation in physiology, and consistent effects of feeding on some traits, overall energy allocation to tissue compared with skeleton growth did not depend on food availability. Extrapolating from our results, estimated whole-assemblage carbon uptake varied >20-fold across different coral assemblages, but this variation was largely driven by differences in the tissue surface area of different colony morphologies, rather than by differences in surface-area-specific physiological rates. Our results caution against drawing conclusions about reef productivity based solely on physiological rates measured per unit tissue surface area. Understanding the causes and consequences of among-species variation in physiological energetics provides insight into the mechanisms that underlie the fluxes of organic matter within reefs, and between reefs and the open ocean.

  19. Controlling factors of Ca isotope fractionation in scleractinian corals evaluated by temperature, pH and light controlled culture experiments

    NASA Astrophysics Data System (ADS)

    Inoue, Mayuri; Gussone, Nikolaus; Koga, Yasuko; Iwase, Akihiro; Suzuki, Atsushi; Sakai, Kazuhiko; Kawahata, Hodaka

    2015-10-01

    In this study, the 44Ca/40Ca ratios of Porites australiensis grown under three different culture experiments composed of temperature, pH and light controlled culture experiments are measured. The temperature dependent isotope fractionation of 0.02‰/°C deduced from this study is similar to inorganic aragonite, but the degree of isotope fractionation is about +0.4‰ offset in corals. These observations agree with earlier results on different coral species, suggesting Ca isotope fractionation during Ca transmembrane transport in corals. While in cultured corals a significant temperature dependence of δ44Ca is observed, the relationships between calcium isotope fractionation and pH as well as light intensity are negligible. Therefore variation of δ44Ca in Porites corals is mainly controlled by temperature. A combination of δ44Ca and Sr/Ca of corals in temperature controlled experiments cannot be explained by Rayleigh type fractionation directly from a fluid, which is seawater-like in terms of δ44Ca and Sr/Ca. Through coral-specific biomineralization processes, overall mean δ44Ca of scleractinian corals including previous studies are different from biogenic aragonites secreted by sclerosponges and pteropods, but are comparable with those of bivalves as well as calcitic coccolithophores and foraminifers. These findings are important for better understanding biomineralization in corals and in order to constrain the Ca isotopic composition of oceanic Ca sinks in response to climate changes and associated with shifts of calcite and aragonite seas.

  20. Gene expression profiles during short-term heat stress; branching vs. massive Scleractinian corals of the Red Sea

    PubMed Central

    Maor-Landaw, Keren

    2016-01-01

    It is well-established that there is a hierarchy of susceptibilities amongst coral genera during heat-stress. However, molecular mechanisms governing these differences are still poorly understood. Here we explored if specific corals possessing different morphologies and different susceptibilities to heat stress may manifest varied gene expression patterns. We examined expression patterns of seven genes in the branching corals Stylophora pistillata and Acropora eurystoma and additionally in the massive robust coral, Porites sp. The tested genes are representatives of key cellular processes occurring during heat-stress in Cnidaria: oxidative stress, ER stress, energy metabolism, DNA repair and apoptosis. Varied response to the heat-stress, in terms of visual coral paling, algal maximum quantum yield and host gene expression was evident in the different growth forms. The two branching corals exhibited similar overall responses that differed from that of the massive coral. A. eurystoma that is considered as a susceptible species did not bleach in our experiment, but tissue sloughing was evident at 34 °C. Interestingly, in this species redox regulation genes were up-regulated at the very onset of the thermal challenge. In S. pistillata, bleaching was evident at 34 °C and most of the stress markers were already up-regulated at 32 °C, either remaining highly expressed or decreasing when temperatures reached 34 °C. The massive Porites species displayed severe bleaching at 32 °C but stress marker genes were only significantly elevated at 34 °C. We postulate that by expelling the algal symbionts from Porites tissues, oxidation damages are reduced and stress genes are activated only at a progressed stage. The differential gene expression responses exhibited here can be correlated with the literature well-documented hierarchy of susceptibilities amongst coral morphologies and genera in Eilat’s coral reef. PMID:27069783

  1. Vibrio sp. causing Porites ulcerative white spot disease.

    PubMed

    Arboleda, Mark D M; Reichardt, Wolfgang T

    2010-06-11

    The causative agent of the Indo-Pacific coral disease, Porites ulcerative white spot syndrome (PUWS), that affects Porites spp. and a few other coral genera has so far remained unidentified. Inoculation of thiosulphate citrate bile sucrose (TCBS) agar with tissue material from Porites cylindrica infected with white spot produced colonies of approximately 3 mm diameter consisting of Gram-negative, motile, non-sucrose-fermenting, slightly curved rods with a minimum NaCl requirement of 0.3%. Three of these putative Vibrio sp. isolates were used for infection trials that included different stages of cell growth. Four modes of inoculation and 3 stages of bacterial cell growth were considered for testing Koch's postulates. Stationary phase cells proved more consistently infectious than did exponentially growing or starved cells using a 1-step immersion technique at cell concentrations of 10(4) cells ml(-1). A 1-step immersion technique proved more reliable in producing signs of white spot than did other techniques, such as injection, smearing and 2-step immersion of the inoculum. At inoculum densities >10(4) cells ml(-1) further signs of disease, such as tissue degradation and bleaching, also became evident. At elevated temperatures (>29 degrees C) bleaching remained absent for at least 2 mo from non-inoculated corals serving as controls, but was observed in artificially infected coral fragments. Of the 9 seawater aquaria containing healthy specimens of P. cylindrica, 6 showed signs of white spot 15 d after infection with an isolate tentatively identified as Vibrio sp. Based on 99% similarity of its 16S rRNA gene sequence and selected phenotypical features, this isolate revealed a close relationship to V. natriegens and V. parahaemolyticus.

  2. Use of scleractinian corals to indicate marine pollution in the northern Gulf of Aqaba, Jordan.

    PubMed

    Barakat, S A; Al-Rousan, S; Al-Trabeen, M S

    2015-02-01

    The actual and fatal concentrations of selected heavy metals, including cadmium, cobalt, copper, lead, nickel, and zinc in corals from the Gulf of Aqaba were determined. Several living coral samples of different species (e.g., Porites) were collected from shallow depths (of about 5 m) at a number of sites along the Jordanian Gulf of Aqaba coast. The coral samples were collected using either a pneumatic diamond drill corer (for Porites) or a hammer and chisel (for other branched species). Some of the corals that had been collected were analyzed for heavy metals using atomic absorption spectrometry, and other samples were used in incubation experiments. The heavy metal concentrations were determined separately in the coral skeleton and the tissue layer. Heavy metal concentrations have not previously been determined in corals from the Gulf of Aqaba. We conclude that corals are suitable for use as proxy tools for assessing environmental pollution (i.e., they are bioindicators) in the Gulf of Aqaba and the Red Sea. Therefore, this study provides useful information on the degree of heavy metal contamination in the study area.

  3. Inhibition of coral recruitment by macroalgae and cyanobacteria

    USGS Publications Warehouse

    Kuffner, I.B.; Walters, L.J.; Becerro, M.A.; Paul, V.J.; Ritson-Williams, R.; Beach, K.S.

    2006-01-01

    Coral recruitment is a key process in the maintenance and recovery of coral reef ecosystems. While intense competition between coral and algae is often assumed on reefs that have undergone phase shifts from coral to algal dominance, data examining the competitive interactions involved, particularly during the larval and immediate post-settlement stage, are scarce. Using a series of field and outdoor seawater table experiments, we tested the hypothesis that common species of macroalgae and cyanobacteria inhibit coral recruitment. We examined the effects of Lyngbya spp., Dictyota spp., Lobophora variegata (J. V. Lamouroux) Womersley, and Chondrophycus poiteaui (J. V. Lamouroux) Nam (formerly Laurencia poiteaui) on the recruitment success of Porites astreoides larvae. All species but C. poiteaui caused either recruitment inhibition or avoidance behavior in P. astreoides larvae, while L. confervoides and D. menstrualis significantly increased mortality rates of P. astreoides recruits. We also tested the effect of some of these macrophytes on larvae of the gorgonian octocoral Briareum asbestinum. Exposure to Lyngbya majuscula reduced survival and recruitment in the octocoral larvae. Our results provide evidence that algae and cyanobacteria use tactics beyond space occupation to inhibit coral recruitment. On reefs experiencing phase shifts or temporary algal blooms, the restocking of adult coral populations may be slowed due to recruitment inhibition, thereby perpetuating reduced coral cover and limiting coral community recovery. ?? Inter-Research 2006.

  4. Coral reproduction in Western Australia

    PubMed Central

    Speed, Conrad W.; Babcock, Russ

    2016-01-01

    the full moon. The timing of the full moon determined whether spawning was split over two months, which was common on tropical reefs. There were few data available for non-Acropora corals, which may have different patterns of reproduction. For example, the massive Porites seemed to spawn through spring to autumn on Kimberley Oceanic reefs and during summer in the Pilbara region, where other common corals (e.g. Turbinaria & Pavona) also displayed different patterns of reproduction to the Acropora. The brooding corals (Isopora & Seriatopora) on Kimberley Oceanic reefs appeared to planulate during many months, possibly with peaks from spring to autumn; a similar pattern is likely on other WA reefs. Gaps in knowledge were also due to the difficulty in identifying species and issues with methodology. We briefly discuss some of these issues and suggest an approach to quantifying variation in reproductive output throughout a year. PMID:27231651

  5. Coral reproduction in Western Australia.

    PubMed

    Gilmour, James; Speed, Conrad W; Babcock, Russ

    2016-01-01

    full moon. The timing of the full moon determined whether spawning was split over two months, which was common on tropical reefs. There were few data available for non-Acropora corals, which may have different patterns of reproduction. For example, the massive Porites seemed to spawn through spring to autumn on Kimberley Oceanic reefs and during summer in the Pilbara region, where other common corals (e.g. Turbinaria & Pavona) also displayed different patterns of reproduction to the Acropora. The brooding corals (Isopora & Seriatopora) on Kimberley Oceanic reefs appeared to planulate during many months, possibly with peaks from spring to autumn; a similar pattern is likely on other WA reefs. Gaps in knowledge were also due to the difficulty in identifying species and issues with methodology. We briefly discuss some of these issues and suggest an approach to quantifying variation in reproductive output throughout a year.

  6. Octocoral Species Assembly and Coexistence in Caribbean Coral Reefs

    PubMed Central

    Velásquez, Johanna; Sánchez, Juan A.

    2015-01-01

    Background What are the determinant factors of community assemblies in the most diverse ecosystem in the ocean? Coral reefs can be divided in continental (i.e., reefs that develop on the continental shelf, including siliciclastic reefs) and oceanic (i.e., far off the continental shelf, usually on volcanic substratum); whether or not these habitat differences impose community-wide ecological divergence or species exclusion/coexistence with evolutionary consequences, is unknown. Methods Studying Caribbean octocorals as model system, we determined the phylogenetic community structure in a coral reef community, making emphasis on species coexistence evidenced on trait evolution and environmental feedbacks. Forty-nine species represented in five families constituted the species pool from which a phylogenetic tree was reconstructed using mtDNA. We included data from 11 localities in the Western Caribbean (Colombia) including most reef types. To test diversity-environment and phenotype-environment relationships, phylogenetic community structure and trait evolution we carried out comparative analyses implementing ecological and evolutionary approaches. Results Phylogenetic inferences suggest clustering of oceanic reefs (e.g., atolls) contrasting with phylogenetic overdispersion of continental reefs (e.g., reefs banks). Additionally, atolls and barrier reefs had the highest species diversity (Shannon index) whereas phylogenetic diversity was higher in reef banks. The discriminant component analysis supported this differentiation between oceanic and continental reefs, where continental octocoral species tend to have greater calyx apertures, thicker branches, prominent calyces and azooxanthellate species. This analysis also indicated a clear separation between the slope and the remaining habitats, caused by the presence or absence of Symbiodinium. K statistic analysis showed that this trait is conserved as well as the branch shape. Discussion There was strong octocoral

  7. Differential survival of coral transplants on various substrates under elevated water temperatures.

    PubMed

    Yap, Helen T

    2004-08-01

    Closely related scleractinian coral species that exhibited similar survival patterns under relatively normal field conditions responded very differently to the occurrence of an environmental disturbance. The two species studied were Porites cylindrica and Porites rus which occur in the same reef zones in shallow reef flats. Transplants of both species were evenly distributed and attached to three different types of substrate: live coral colonies of P. cylindrica, dead coral colonies (also of P. cylindrica), and epoxy coated metal grids that were raised above the sandy substrate. With the onset of above-normal water temperatures due to the El Niño episode of 1998, P. cylindrica transplants immediately showed signs of bleaching stress and tissue necrosis, followed by algal overgrowth and mortality soon afterwards. In contrast, transplants of P. rus bleached more slowly and suffered less mortality, with a few actually showing signs of recovery at the end of the experimental period which covered a total of 14 weeks. These differences in responses could be attributed to properties of the symbiotic zooxanthellae, of the host coral tissue itself, or both. Over-all, survival was good on the metal grids (average of 35%), and on the live coral (average of 22%). It was poor on the dead coral (average of 6%). The metal grids as well as live coral tissue apparently provided a favorable substrate for the attached coral fragments, even for those of a different species. Under the conditions of this particular study, attachment of live coral fragments on already dead colonies for the purpose of increasing live coral cover on the reef did not yield favorable results. This is an area that requires further investigation.

  8. Coral reef recovery in the Galápagos Islands: the northernmost islands (Darwin and Wenman)

    NASA Astrophysics Data System (ADS)

    Glynn, Peter W.; Riegl, Bernhard; Purkis, Samuel; Kerr, Jeremy M.; Smith, Tyler B.

    2015-06-01

    The remote northernmost Galápagos Islands, Darwin and Wenman, exhibited well-developed coral communities in 1975, which were severely degraded during the 1982-1983 El Niño warming event. Mapping of the coral reef at Darwin, herein Wellington Reef, shows it presently to be the largest known structural reef in the Galápagos. It consists of numerous 1- to 3-m-high Porites framework towers or stacks and overlies a carbonate (coral/calcareous sediments) basement. Pre-disturbance Wellington Reef was constructed chiefly by Porites lobata and Pocillopora elegans, and Wenman coral cover was dominated by Pavona clavus and Porites lobata. Subsequent surveys in 2012 have demonstrated robust recovery in spite of ENSO thermal shock events, involving both high and low stressful temperatures that have caused tissue bleaching and mortality. No losses of coral species have been observed. Radiocarbon dating of 1- to 3-m-high poritid framework stacks, from their peaks to bases, revealed modern ages of up to 690 yr. Incremental stack growth rates ranged from 0.15-0.39 to 1.04-2.40 cm yr-1. The former are equivalent to framework accretion rates of 1.5-3.9 m Kyr-1, the latter to coral skeletal growth rates of 1.0-2.4 cm yr-1. Coral recovery in the central and southern Galápagos has been nonexistent to low compared with the northern islands, due chiefly to much higher population densities and destructive grazing pressure of the echinoid Eucidaris galapagensis. Thus, coral reef resistance to ENSO perturbations and recovery potential in the Galápagos are influenced by echinoid bioerosion that varies significantly among islands.

  9. Gross and Microscopic Lesions in Corals from Micronesia.

    PubMed

    Work, T M; Aeby, G S; Hughen, K A

    2016-01-01

    The authors documented gross and microscopic morphology of lesions in corals on 7 islands spanning western, southern, and eastern Micronesia, sampling 76 colonies comprising 30 species of corals among 18 genera, with Acropora, Porites, and Montipora dominating. Tissue loss comprised the majority of gross lesions sampled (41%), followed by discoloration (30%) and growth anomaly (29%). Of 31 cases of tissue loss, most lesions were subacute (48%), followed by acute and chronic (26% each). Of 23 samples with discoloration, most were dark discoloration (40%), with bleaching and other discoloration each constituting 30%. Of 22 growth anomalies, umbonate growth anomalies composed half, with exophytic, nodular, and rugose growth anomalies composing the remainder. On histopathology, for 9 cases of dark discoloration, fungal infections predominated (77%); for 7 bleached corals, depletion of zooxanthellae from the gastrodermis made up a majority of microscopic diagnoses (57%); and for growth anomalies other than umbonate, hyperplasia of the basal body wall was the most common microscopic finding (63%). For the remainder of the gross lesions, no single microscopic finding constituted >50% of the total. Host response varied with the agent present on histology. Fragmentation of tissues was most often associated with algae (60%), whereas necrosis dominated (53%) for fungi. Two newly documented potentially symbiotic tissue-associated metazoans were seen in Porites and Montipora. Findings of multiple potential etiologies for a given gross lesion highlight the importance of incorporating histopathology in coral disease surveys. This study also expands the range of corals infected with cell-associated microbial aggregates.

  10. Gross and microscopic lesions in corals from Micronesia

    USGS Publications Warehouse

    Work, Thierry M.; Aeby, Greta S.; Hughen, Konrad A.

    2015-01-01

    The authors documented gross and microscopic morphology of lesions in corals on 7 islands spanning western, southern, and eastern Micronesia, sampling 76 colonies comprising 30 species of corals among 18 genera, with Acropora, Porites, and Montipora dominating. Tissue loss comprised the majority of gross lesions sampled (41%), followed by discoloration (30%) and growth anomaly (29%). Of 31 cases of tissue loss, most lesions were subacute (48%), followed by acute and chronic (26% each). Of 23 samples with discoloration, most were dark discoloration (40%), with bleaching and other discoloration each constituting 30%. Of 22 growth anomalies, umbonate growth anomalies composed half, with exophytic, nodular, and rugose growth anomalies composing the remainder. On histopathology, for 9 cases of dark discoloration, fungal infections predominated (77%); for 7 bleached corals, depletion of zooxanthellae from the gastrodermis made up a majority of microscopic diagnoses (57%); and for growth anomalies other than umbonate, hyperplasia of the basal body wall was the most common microscopic finding (63%). For the remainder of the gross lesions, no single microscopic finding constituted >50% of the total. Host response varied with the agent present on histology. Fragmentation of tissues was most often associated with algae (60%), whereas necrosis dominated (53%) for fungi. Two newly documented potentially symbiotic tissue-associated metazoans were seen in Porites and Montipora. Findings of multiple potential etiologies for a given gross lesion highlight the importance of incorporating histopathology in coral disease surveys. This study also expands the range of corals infected with cell-associated microbial aggregates.

  11. Miocene reef corals: A review

    SciTech Connect

    Frost, S.H.

    1988-01-01

    Tectonic blockage in the Middle East of westward-flowing Tethys surface circulation during the latest Oligocene led to creation in the earliest Miocene of endemic Mediterranean, Western Atlantic-Caribbean, and Indo-Pacific realms. A great reduction in reef coral diversity from 60-80 Oligocene species to 25-35 early Miocene species occurred in the Western Atlantic-Caribbean and Mediterranean areas accompanied by a decrease in reef growth. A slower and less drastic change apparently occurred in the Indo-Pacific area. Early Miocene reef corals of the Western Atlantic-Caribbean comprise a transition between the cosmopolitan Oligocene fauna and its endemic mid-Miocene to modern counterpart. Although early Miocene reefs were dominated by a Porites-Montastrea assemblage, eastward flow of Pacific circulation brought with it ''exotic'' corals such as Coscinaraea and Pseudocolumnastrea. Also, many cosmopolitan genera persisted from the Oligocene. During the middle to late Miocene, most of the species still living on Holocene reefs evolved. As the Mediterranean basin became more restricted, there was a slow decline in reef corals from 20 - 25 species in the Aquitainian to less than five species in the Messinian. Eustatic lowstand led to the extinction of reef-building corals in the late Messinian. In the Indo-Pacific, Neogene evolution of reef corals was conservative. Excluding the Acroporidae and Seriatoporidae, most Holocene framework species had evolved by the middle Miocene. Interplay between regional tectonics and eustatic sea level changes led to extensive development of middle to late Miocene pinnacle reefs over the southwestern Pacific.

  12. The Coral Trait Database, a curated database of trait information for coral species from the global oceans

    NASA Astrophysics Data System (ADS)

    Madin, Joshua S.; Anderson, Kristen D.; Andreasen, Magnus Heide; Bridge, Tom C. L.; Cairns, Stephen D.; Connolly, Sean R.; Darling, Emily S.; Diaz, Marcela; Falster, Daniel S.; Franklin, Erik C.; Gates, Ruth D.; Hoogenboom, Mia O.; Huang, Danwei; Keith, Sally A.; Kosnik, Matthew A.; Kuo, Chao-Yang; Lough, Janice M.; Lovelock, Catherine E.; Luiz, Osmar; Martinelli, Julieta; Mizerek, Toni; Pandolfi, John M.; Pochon, Xavier; Pratchett, Morgan S.; Putnam, Hollie M.; Roberts, T. Edward; Stat, Michael; Wallace, Carden C.; Widman, Elizabeth; Baird, Andrew H.

    2016-03-01

    Trait-based approaches advance ecological and evolutionary research because traits provide a strong link to an organism’s function and fitness. Trait-based research might lead to a deeper understanding of the functions of, and services provided by, ecosystems, thereby improving management, which is vital in the current era of rapid environmental change. Coral reef scientists have long collected trait data for corals; however, these are difficult to access and often under-utilized in addressing large-scale questions. We present the Coral Trait Database initiative that aims to bring together physiological, morphological, ecological, phylogenetic and biogeographic trait information into a single repository. The database houses species- and individual-level data from published field and experimental studies alongside contextual data that provide important framing for analyses. In this data descriptor, we release data for 56 traits for 1547 species, and present a collaborative platform on which other trait data are being actively federated. Our overall goal is for the Coral Trait Database to become an open-source, community-led data clearinghouse that accelerates coral reef research.

  13. The Coral Trait Database, a curated database of trait information for coral species from the global oceans.

    PubMed

    Madin, Joshua S; Anderson, Kristen D; Andreasen, Magnus Heide; Bridge, Tom C L; Cairns, Stephen D; Connolly, Sean R; Darling, Emily S; Diaz, Marcela; Falster, Daniel S; Franklin, Erik C; Gates, Ruth D; Hoogenboom, Mia O; Huang, Danwei; Keith, Sally A; Kosnik, Matthew A; Kuo, Chao-Yang; Lough, Janice M; Lovelock, Catherine E; Luiz, Osmar; Martinelli, Julieta; Mizerek, Toni; Pandolfi, John M; Pochon, Xavier; Pratchett, Morgan S; Putnam, Hollie M; Roberts, T Edward; Stat, Michael; Wallace, Carden C; Widman, Elizabeth; Baird, Andrew H

    2016-03-29

    Trait-based approaches advance ecological and evolutionary research because traits provide a strong link to an organism's function and fitness. Trait-based research might lead to a deeper understanding of the functions of, and services provided by, ecosystems, thereby improving management, which is vital in the current era of rapid environmental change. Coral reef scientists have long collected trait data for corals; however, these are difficult to access and often under-utilized in addressing large-scale questions. We present the Coral Trait Database initiative that aims to bring together physiological, morphological, ecological, phylogenetic and biogeographic trait information into a single repository. The database houses species- and individual-level data from published field and experimental studies alongside contextual data that provide important framing for analyses. In this data descriptor, we release data for 56 traits for 1547 species, and present a collaborative platform on which other trait data are being actively federated. Our overall goal is for the Coral Trait Database to become an open-source, community-led data clearinghouse that accelerates coral reef research.

  14. The Coral Trait Database, a curated database of trait information for coral species from the global oceans

    PubMed Central

    Madin, Joshua S.; Anderson, Kristen D.; Andreasen, Magnus Heide; Bridge, Tom C.L.; Cairns, Stephen D.; Connolly, Sean R.; Darling, Emily S.; Diaz, Marcela; Falster, Daniel S.; Franklin, Erik C.; Gates, Ruth D.; Hoogenboom, Mia O.; Huang, Danwei; Keith, Sally A.; Kosnik, Matthew A.; Kuo, Chao-Yang; Lough, Janice M.; Lovelock, Catherine E.; Luiz, Osmar; Martinelli, Julieta; Mizerek, Toni; Pandolfi, John M.; Pochon, Xavier; Pratchett, Morgan S.; Putnam, Hollie M.; Roberts, T. Edward; Stat, Michael; Wallace, Carden C.; Widman, Elizabeth; Baird, Andrew H.

    2016-01-01

    Trait-based approaches advance ecological and evolutionary research because traits provide a strong link to an organism’s function and fitness. Trait-based research might lead to a deeper understanding of the functions of, and services provided by, ecosystems, thereby improving management, which is vital in the current era of rapid environmental change. Coral reef scientists have long collected trait data for corals; however, these are difficult to access and often under-utilized in addressing large-scale questions. We present the Coral Trait Database initiative that aims to bring together physiological, morphological, ecological, phylogenetic and biogeographic trait information into a single repository. The database houses species- and individual-level data from published field and experimental studies alongside contextual data that provide important framing for analyses. In this data descriptor, we release data for 56 traits for 1547 species, and present a collaborative platform on which other trait data are being actively federated. Our overall goal is for the Coral Trait Database to become an open-source, community-led data clearinghouse that accelerates coral reef research. PMID:27023900

  15. Reactive oxygen species (ROS) and dimethylated sulphur compounds in coral explants under acute thermal stress.

    PubMed

    Gardner, Stephanie G; Raina, Jean-Baptiste; Ralph, Peter J; Petrou, Katherina

    2017-03-08

    Coral bleaching is intensifying with global climate change. While the causes for these catastrophic events are well understood, the cellular mechanism that triggers bleaching is not well established. Our understanding of coral bleaching processes is hindered by the lack of robust methods for studying interactions between host and symbiont at the single-cell level. Here we exposed coral explants to acute thermal stress and measured oxidative stress, more specifically, reactive oxygen species (ROS), in individual symbiont cells. Furthermore, we measured concentrations of dimethylsulphoniopropionate (DMSP) and dimethylsulphoxide (DMSO) to elucidate the role of these compounds in coral antioxidant function. This work demonstrates the application of coral explants for investigating coral physiology and biochemistry under thermal stress and delivers a new approach to study host-symbiont interactions at the microscale, allowing us to directly link intracellular ROS with DMSP and DMSO dynamics.

  16. Disease dynamics of Porites bleaching with tissue loss: prevalence, virulence, transmission, and environmental drivers.

    PubMed

    Sudek, M; Williams, G J; Runyon, C; Aeby, G S; Davy, S K

    2015-02-10

    The prevalence, number of species affected, and geographical extent of coral diseases have been increasing worldwide. We present ecological data on the coral disease Porites bleaching with tissue loss (PBTL) from Kaneohe Bay, Oahu (Hawaii, USA), affecting P. compressa. This disease is prevalent throughout the year, although it shows spatio-temporal variability with peak prevalence during the warmer summer months. Temporal variability in disease prevalence showed a strong positive relationship with elevated water temperature. Spatially, PBTL prevalence peaked in clearer waters (lower turbidity) with higher water flow and higher densities of parrotfish, together explaining approximately 26% of the spatial variability in PBTL prevalence. However, the relatively poor performance of the spatial model suggests that other, unmeasured factors may be more important in driving spatial prevalence. PBTL was not transmissible through direct contact or the water column in controlled aquaria experiments, suggesting that this disease may not be caused by a pathogen, is not highly infectious, or perhaps requires a vector for transmission. In general, PBTL results in partial tissue mortality of affected colonies; on average, one-third of the tissue is lost. This disease can affect the same colonies repeatedly, suggesting a potential for progressive damage which could cause increased tissue loss over time. P. compressa is the main framework-building species in Kaneohe Bay; PBTL therefore has the potential to negatively impact the structure of the reefs at this location.

  17. Biological review of 82 species of coral petitioned to be included in the Endangered Species Act

    USGS Publications Warehouse

    Brainard, Russell E.; Birkeland, Charles; Eakin, C. Mark; McElhany, Paul; Miller, Margaret W.; Patterson, Matt; Piniak, G.A.

    2011-01-01

    The BRT considered two major factors in conducting this review. The first factor was the interaction of natural phenomena and anthropogenic stressors that could potentially contribute to coral extinction. After extensive review of available scientific information, the BRT considers ocean warming, disease, and ocean acidification to be the most influential threats in posing extinction risks to the 82 candidate coral species between now and the year 2100. Threats of local origin but having widespread impact, such as sedimentation, nutrient enrichment, and fishing, were considered of medium importance in determining extinction risks. It is acknowledged that many other threats (e.g., physical damage from storms or ship groundings, invasive species or predator outbreaks, collection and trade) also negatively affect corals, often acutely and dramatically, but generally at relatively small local scales. These local threats were considered to be of limited scope and not deemed to contribute appreciably to the risk of species extinction, except in those special cases where species have restricted geographic or habitat ranges or species have already undergone precipitous population declines such that these local threats further contribute to depensatory processes that can magnify extinction risks (e.g., feedback-loops whereby individual survival decreases with smaller population size). The BRT acknowledges that local and global threats operate on different time scales and, though there is high confidence in the general progression of some key global threats, such as ocean warming and ocean acidification, there is much less certainty in the timing and spatial patterns of these threats. There is also substantial uncertainty in the abilities of the 82 candidate coral species to tolerate or adapt to each of the threats examined, as well as uncertainty in the dynamics of multiple simultaneous stresses. The BRT specifically identified increasing human population levels and the

  18. Effects of Hydrogen Peroxide on Coral Photosynthesis and Calcification

    NASA Astrophysics Data System (ADS)

    Higuchi, T.; Fujimura, H.; Arakaki, T.; Oomori, T.

    2007-12-01

    The widely-observed decline of coral reefs is considered to be caused by changes in the environment by natural and anthropogenic activities. As one important factor, the run-off of various matters from human activities to the coastal seawater poses stresses to the corals by degrading the quality of the seawater. In Okinawa, Japan, red- soil running off from the developed land has been a major environmental issue since 1980s. Hydrogen peroxide (HOOH), a strong active oxygen species, is one of the photochemically formed chemicals in the red-soil-polluted seawater. Recent photochemical studies of seawater showed that HOOH photo-formation was faster in the red- soil-polluted seawater than clean seawater. We studied the effects of HOOH on corals by studying the changes in coral carbon metabolisms such as photosynthesis and calcification, which are indicators of the physiological state of a coral colony. The corals were exposed to various concentrations of HOOH (0, 0.3, 3 μM). Two massive coral species of Porites sp. and Goniastrea aspera and one branch coral of Galaxea facicularis were used for the exposure experiments. The control experiments showed that when no HOOH was added, metabolisms of each coral colony were relatively stable. On the other hand, when HOOH was added to the seawater, we observed obvious changes in the coral metabolisms in all the coral species. When 0.3 μM HOOH was added, photosynthesis decreased by 14% and calcification decreased by 17% within 3 days, compared with the control. When 3 μM HOOH was added, photosynthesis decreased by 21% and calcification decreased by 41% within 3 days, compared with the control. Our study showed that higher concentrations of HOOH posed more stress to the coral colonies.

  19. Annual coral bleaching and the long-term recovery capacity of coral.

    PubMed

    Schoepf, Verena; Grottoli, Andréa G; Levas, Stephen J; Aschaffenburg, Matthew D; Baumann, Justin H; Matsui, Yohei; Warner, Mark E

    2015-11-22

    Mass bleaching events are predicted to occur annually later this century. Nevertheless, it remains unknown whether corals will be able to recover between annual bleaching events. Using a combined tank and field experiment, we simulated annual bleaching by exposing three Caribbean coral species (Porites divaricata, Porites astreoides and Orbicella faveolata) to elevated temperatures for 2.5 weeks in 2 consecutive years. The impact of annual bleaching stress on chlorophyll a, energy reserves, calcification, and tissue C and N isotopes was assessed immediately after the second bleaching and after both short- and long-term recovery on the reef (1.5 and 11 months, respectively). While P. divaricata and O. faveolata were able to recover from repeat bleaching within 1 year, P. astreoides experienced cumulative damage that prevented full recovery within this time frame, suggesting that repeat bleaching had diminished its recovery capacity. Specifically, P. astreoides was not able to recover protein and carbohydrate concentrations. As energy reserves promote bleaching resistance, failure to recover from annual bleaching within 1 year will likely result in the future demise of heat-sensitive coral species.

  20. Annual coral bleaching and the long-term recovery capacity of coral

    PubMed Central

    Schoepf, Verena; Grottoli, Andréa G.; Levas, Stephen J.; Aschaffenburg, Matthew D.; Baumann, Justin H.; Matsui, Yohei; Warner, Mark E.

    2015-01-01

    Mass bleaching events are predicted to occur annually later this century. Nevertheless, it remains unknown whether corals will be able to recover between annual bleaching events. Using a combined tank and field experiment, we simulated annual bleaching by exposing three Caribbean coral species (Porites divaricata, Porites astreoides and Orbicella faveolata) to elevated temperatures for 2.5 weeks in 2 consecutive years. The impact of annual bleaching stress on chlorophyll a, energy reserves, calcification, and tissue C and N isotopes was assessed immediately after the second bleaching and after both short- and long-term recovery on the reef (1.5 and 11 months, respectively). While P. divaricata and O. faveolata were able to recover from repeat bleaching within 1 year, P. astreoides experienced cumulative damage that prevented full recovery within this time frame, suggesting that repeat bleaching had diminished its recovery capacity. Specifically, P. astreoides was not able to recover protein and carbohydrate concentrations. As energy reserves promote bleaching resistance, failure to recover from annual bleaching within 1 year will likely result in the future demise of heat-sensitive coral species. PMID:26582020

  1. The Role of Maternal Nutrition on Oocyte Size and Quality, with Respect to Early Larval Development in The Coral-Eating Starfish, Acanthaster planci

    PubMed Central

    Pratchett, Morgan S.; Kerr, Alexander M.; Rivera-Posada, Jairo A.

    2016-01-01

    Variation in local environmental conditions can have pronounced effects on the population structure and dynamics of marine organisms. Previous studies on crown-of-thorns starfish, Acanthaster planci, have primarily focused on effects of water quality and nutrient availability on larval growth and survival, while the role of maternal nutrition on reproduction and larval development has been overlooked. To examine the effects of maternal nutrition on oocyte size and early larval development in A. planci, we pre-conditioned females for 60 days on alternative diets of preferred coral prey (Acropora abrotanoides) versus non-preferred coral prey (Porites rus) and compared resulting gametes and progeny to those produced by females that were starved over the same period. Females fed ad libitum with Acropora increased in weight, produced heavier gonads and produced larger oocytes compared to Porites-fed and starved females. Fed starfish (regardless of whether it was Acropora or Porites) produced bigger larvae with larger stomachs and had a higher frequency of normal larvae that reached the late bipinnaria / early brachiolaria stage compared to starved starfish. Females on Acropora diet also produced a higher proportion of larvae that progressed to more advanced stages faster compared to Porites-fed starfish, which progressed faster than starved starfish. These results suggest that maternal provisioning can have important consequences for the quality and quantity of progeny. Because food quality (coral community structure) and quantity (coral abundance) varies widely among reef locations and habitats, local variation in maternal nutrition of A. planci is likely to moderate reproductive success and may explain temporal and spatial fluctuations in abundance of this species. PMID:27327627

  2. Diversities of coral-associated bacteria differ with location, but not species, for three acroporid corals on the Great Barrier Reef.

    PubMed

    Littman, Raechel A; Willis, Bette L; Pfeffer, Christian; Bourne, David G

    2009-05-01

    Patterns in the diversity of bacterial communities associated with three species of Acropora (Acropora millepora, Acropora tenuis and Acropora valida) were compared at two locations (Magnetic Island and Orpheus Island) on the Great Barrier Reef to better understand the nature and specificity of coral-microbial symbioses. Three culture-independent techniques demonstrated consistent bacterial communities among replicate samples of each coral species, confirming that corals associate with specific microbiota. Profiles were also conserved among all three species of Acropora within each location, suggesting that closely related corals of the same genus harbor similar bacterial types. Bacterial community profiles of A. millepora at Orpheus Island were consistent in samples collected throughout the year, indicating a stable community despite temporal changes. However, DGGE and T-RFLP profiles differed on corals from different reefs. Nonmetric multidimensional scaling of T-RFLP profiles showed that samples grouped according to location rather than coral species. Although similar sequences were retrieved from clone libraries of corals at both Magnetic and Orpheus Island, differences in the relative dominant bacterial ribotypes within the libraries drive bacterial community structure at different geographical locations. These results indicate certain bacterial groups associated specifically with corals, but the dominant bacterial genera differ between geographically-spaced corals.

  3. Recognizing diversity in coral symbiotic dinoflagellate communities.

    PubMed

    Apprill, Amy M; Gates, Ruth D

    2007-03-01

    A detailed understanding of how diversity in endosymbiotic dinoflagellate communities maps onto the physiological range of coral hosts is critical to predicting how coral reef ecosystems will respond to climate change. Species-level taxonomy of the dinoflagellate genus Symbiodinium has been predominantly examined using the internal transcribed spacer (ITS) region of the nuclear ribosomal array (rDNA ITS2) and downstream screening for dominant types using denaturing gradient gel electrophoresis (DGGE). Here, ITS2 diversity in the communities of Symbiodinium harboured by two Hawaiian coral species was explored using direct sequencing of clone libraries. We resolved sixfold to eightfold greater diversity per coral species than previously reported, the majority of which corresponds to a novel and distinct phylogenetic lineage. We evaluated how these sequences migrate in DGGE and demonstrate that this method does not effectively resolve this diversity. We conclude that the Porites spp. examined here harbour diverse assemblages of novel Symbiodinium types and that cloning and sequencing is an effective methodological approach for resolving the complexity of endosymbiotic dinoflagellate communities harboured by reef corals.

  4. The reef coral Goniastrea aspera: a `winner' becomes a `loser' during a severe bleaching event in Thailand

    NASA Astrophysics Data System (ADS)

    Brown, B. E.; Dunne, R. P.; Phongsuwan, N.; Patchim, L.; Hawkridge, J. M.

    2014-06-01

    The reef coral Goniastrea aspera is regarded as one of the most environmentally tolerant species on Indo-Pacific reefs. Its demise, following a severe bleaching event in the Andaman Sea in the north-eastern Indian Ocean in 2010, was surprising in view of the rapid recovery of co-existing species such as Porites lutea. Demographic studies of G. aspera at this site showed the population was mainly composed of large individuals, which recruited in the early 1990s. These results, and size-specific mortality observed in G. aspera, post-bleaching, suggest that factors, related to size and age, may have contributed to the coral's marked decline.

  5. Regional-scale dominance of non-framework building corals on Caribbean reefs affects carbonate production and future reef growth.

    PubMed

    Perry, Chris T; Steneck, Robert S; Murphy, Gary N; Kench, Paul S; Edinger, Evan N; Smithers, Scott G; Mumby, Peter J

    2015-03-01

    Coral cover on Caribbean reefs has declined rapidly since the early 1980's. Diseases have been a major driver, decimating communities of framework building Acropora and Orbicella coral species, and reportedly leading to the emergence of novel coral assemblages often dominated by domed and plating species of the genera Agaricia, Porites and Siderastrea. These corals were not historically important Caribbean framework builders, and typically have much smaller stature and lower calcification rates, fuelling concerns over reef carbonate production and growth potential. Using data from 75 reefs from across the Caribbean we quantify: (i) the magnitude of non-framework building coral dominance throughout the region and (ii) the contribution of these corals to contemporary carbonate production. Our data show that live coral cover averages 18.2% across our sites and coral carbonate production 4.1 kg CaCO3  m(-2)  yr(-1) . However, non-framework building coral species dominate and are major carbonate producers at a high proportion of sites; they are more abundant than Acropora and Orbicella at 73% of sites; contribute an average 68% of the carbonate produced; and produce more than half the carbonate at 79% of sites. Coral cover and carbonate production rate are strongly correlated but, as relative abundance of non-framework building corals increases, average carbonate production rates decline. Consequently, the use of coral cover as a predictor of carbonate budget status, without species level production rate data, needs to be treated with caution. Our findings provide compelling evidence for the Caribbean-wide dominance of non-framework building coral taxa, and that these species are now major regional carbonate producers. However, because these species typically have lower calcification rates, continued transitions to states dominated by non-framework building coral species will further reduce carbonate production rates below 'predecline' levels, resulting in shifts

  6. Status of coral reef species at Chabahar Bay, Sistan and Baluchistan, Iran.

    PubMed

    Teymour, Rad A; Sanjani, M S

    2010-04-15

    This study was carried out in the coral growing zone at Chabahar Bay where it located at 25 degrees 17' N and 60 degrees 36'E. It is called horseshoe Bay, because of its semicircle shape. Some destroyer factors have been affected on the health of coral reefs in Chabahar Bay. Port constructions, dredging operations, spearfishing, anchorages and scuba diving activities were distinguished as the most important problems of coral reef in Chabahar Bay. This study was conducted in order to access Semi-Qualitative Indexes of corals in different areas of Chabahar Bay. Five stations were chosen in east and north part of the Bay, where the most construction activities happened. Rectangular Transect and CoralWatch Racket were used to determine the status of the corals. During study, two classes of Hexacoralia and Octocoralia with 15 families were recorded. Twenty one species of hard coral and 10 species of soft coral were recorded. Hexacoralia was recorded the higher number of family with 10 families and 21 species and Octocoralia was recorded the lower with 5 families and 10 species. Hard corals were dominant. The ranges of qualitative indexes showed, of five stations, three of them (stations 2, 4, 5) showed Good Development and two stations (stations 1, 3) showed Fair Development. For the Condition Index, two stations showed Good Condition (stations 1, 5) and two stations showed Fair Condition (stations 2, 3). Only station 4 showed Poor Condition. The ranges of the Succession Index Showed, four stations (stations 1, 2, 3, 4) were in Very poor Succession and one station (stations 5) showed Poor Succession.

  7. Species-area relationships in coral communities: evaluating mechanisms for a commonly observed pattern

    NASA Astrophysics Data System (ADS)

    Huntington, B. E.; Lirman, D.

    2012-12-01

    Landscape-scale attributes of patch size, spatial isolation, and topographic complexity are known to influence diversity and abundance in terrestrial and marine systems, but remain collectively untested for reef-building corals. To investigate the relationship between the coral assemblage and seascape variation in reef habitats, we took advantage of the distinct boundaries, spatial configurations, and topographic complexities among artificial reef patches to overcome the difficulties of manipulating natural reefs. Reef size (m2) was found to be the foremost predictor of coral richness in accordance with species-area relationship predictions. Larger reefs were also found to support significantly higher colony densities, enabling us to reject the null hypothesis of random placement (a sampling artifact) in favor of target area predictions that suggest greater rates of immigration on larger reefs. Unlike the pattern previously documented for reef fishes, topographic complexity was not a significant predictor of any coral assemblage response variable, despite the range of complexity values sampled. Lastly, coral colony density was best explained by both increasing reef size and decreasing reef spatial isolation, a pattern found exclusively among brooding species with shorter larval dispersal distances. We conclude that seascape attributes of reef size and spatial configuration within the seascape can influence the species richness and abundance of the coral community at relatively small spatial scales (<1 km). Specifically, we demonstrate how patterns in the coral communities that have naturally established on these manipulated reefs agree with the target area and island biogeography mechanisms to drive species-area relationships in reef-building corals. Based on the patterns documented in artificial reefs, habitat degradation that results in smaller, more isolated natural reefs may compromise coral diversity.

  8. 78 FR 10601 - Endangered and Threatened Wildlife; 90-Day Finding on a Petition to List 44 Species of Corals as...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-14

    ... cycle and include the order Anthoathecatae (hydrocorals). To date, 134 unique coral taxa have been found... role in the distribution of Alaska coral species, including nutrient flows and productivity, water... directly and indirectly affect cold water corals, yet no empirical studies to date have...

  9. Patterns of coral ecological immunology: variation in the responses of Caribbean corals to elevated temperature and a pathogen elicitor.

    PubMed

    Palmer, Caroline V; McGinty, Elizabeth S; Cummings, David J; Smith, Stephanie M; Bartels, Erich; Mydlarz, Laura D

    2011-12-15

    Disease epizootics are increasing with climatic shifts, yet within each system only a subset of species are identified as the most vulnerable. Understanding ecological immunology patterns as well as environmental influences on immune defenses will provide insight into the persistence of a functional system through adverse conditions. Amongst the most threatened ecosystems are coral reefs, with coral disease epizootics and thermal stress jeopardizing their survival. Immune defenses were investigated within three Caribbean corals, Montastraea faveolata, Stephanocoenia intersepta and Porites astreoides, which represent a range of disease and bleaching susceptibilities. Levels of several immune parameters were measured in response to elevated water temperature and the presence of a commercial pathogen-associated molecular pattern (PAMP) - lipopolysaccharide (LPS) - as an elicitor of the innate immune response. Immune parameters included prophenoloxidase (PPO) activity, melanin concentration, bactericidal activity, the antioxidants peroxidase and catalase, and fluorescent protein (FP) concentration. LPS induced an immune response in all three corals, although each species responded differently to the experimental treatments. For example, M. faveolata, a disease-susceptible species, experienced significant decreases in bactericidal activity and melanin concentration after exposure to LPS and elevated temperature alone. Porites astreoides, a disease-resistant species, showed increased levels of enzymatic antioxidants upon exposure to LPS independently and increased PPO activity in response to the combination of LPS and elevated water temperature. This study demonstrates the ability of reef-building corals to induce immune responses in the presence of PAMPs, indicating activation of PAMP receptors and the transduction of appropriate signals leading to immune effector responses. Furthermore, these data address the emerging field of ecological immunology by highlighting

  10. The effects of habitat on coral bleaching responses in Kenya.

    PubMed

    Grimsditch, Gabriel; Mwaura, Jelvas M; Kilonzo, Joseph; Amiyo, Nassir

    2010-06-01

    This study examines the bleaching responses of scleractinian corals at four sites in Kenya (Kanamai, Vipingo, Mombasa and Nyali) representing two distinct lagoon habitats (relatively shallow and relatively deep). Bleaching incidence was monitored for the whole coral community, while zooxanthellae densities and chlorophyll levels were monitored for target species (Pocillopora damicornis, Porites lutea, and Porites cylindrica) during a non-bleaching year (2006) and a year of mild-bleaching (2007). Differences in bleaching responses between habitats were observed, with shallower sites Kanamai and Vipingo exhibiting lower bleaching incidence than deeper sites Nyali and Mombasa. These shallower lagoons display more fluctuating thermal and light environments than the deeper sites, suggesting that corals in the shallower lagoons have acclimatized and/or adapted to the fluctuating environmental conditions they endure on a daily basis and have become more resistant to bleaching stress. In deeper sites that did exhibit higher bleaching (Mombasa and Nyali), it was found that coral recovery occurred more quickly in the protected area than in the non-protected area.

  11. Reef fishes in biodiversity hotspots are at greatest risk from loss of coral species.

    PubMed

    Holbrook, Sally J; Schmitt, Russell J; Messmer, Vanessa; Brooks, Andrew J; Srinivasan, Maya; Munday, Philip L; Jones, Geoffrey P

    2015-01-01

    Coral reef ecosystems are under a variety of threats from global change and anthropogenic disturbances that are reducing the number and type of coral species on reefs. Coral reefs support upwards of one third of all marine species of fish, so the loss of coral habitat may have substantial consequences to local fish diversity. We posit that the effects of habitat degradation will be most severe in coral regions with highest biodiversity of fishes due to greater specialization by fishes for particular coral habitats. Our novel approach to this important but untested hypothesis was to conduct the same field experiment at three geographic locations across the Indo-Pacific biodiversity gradient (Papua New Guinea; Great Barrier Reef, Australia; French Polynesia). Specifically, we experimentally explored whether the response of local fish communities to identical changes in diversity of habitat-providing corals was independent of the size of the regional species pool of fishes. We found that the proportional reduction (sensitivity) in fish biodiversity to loss of coral diversity was greater for regions with larger background species pools, reflecting variation in the degree of habitat specialization of fishes across the Indo-Pacific diversity gradient. This result implies that habitat-associated fish in diversity hotspots are at greater risk of local extinction to a given loss of habitat diversity compared to regions with lower species richness. This mechanism, related to the positive relationship between habitat specialization and regional biodiversity, and the elevated extinction risk this poses for biodiversity hotspots, may apply to species in other types of ecosystems.

  12. Latitudinal species diversity gradient of mushroom corals off eastern Australia: a baseline from the 1970s

    NASA Astrophysics Data System (ADS)

    Hoeksema, Bert W.

    2015-11-01

    Based on a study of mushroom coral species of eastern Australia, a decrease in species richness can be discerned from north to south. Eastern Australia, including the Great Barrier Reef (GBR), is one of only few coral reef areas suitable for studies on large-scale latitudinal biodiversity patterns. Such patterns may help to recognize biogeographic boundaries and factors regulating biodiversity. Owing to the eastern Australian long coastline, such studies are a logistic challenge unless reliable distribution data are already available, as in museum collections. A large coral collection predominantly sampled from this area in the 1970s is present in the Museum of Tropical Queensland (MTQ). The scleractinian family Fungiidae (mushroom corals), representing about 10% of Indo-Pacific reef coral species, was selected as proxy. It was represented by 1289 specimens belonging to 34 species with latitudinal ranges between 09°09‧S and 31°28‧S. The fauna of the northernmost reefs in the Gulf of Papua and the Torres Strait, and north of the Great Barrier Reef Marine Park (GBRMP), was represented by a maximum of 30 fungiids. From here a southward decline in species number was observed, down to Lord Howe Island with only one species. Together with previous records, the mushroom coral fauna of eastern Australia consists of 37 species, which is more diverse than hitherto known and similar to numbers found in the Coral Triangle. Future field surveys in the GBR should specifically target rarely known species, which are mainly small and found at depths >25 m. In the light of global climate change, they may also show whether previously recorded species are still present and whether their latitudinal ranges have shifted, using the 1970s records as a baseline.

  13. The effect of temperature stress on coral- Symbiodinium associations containing distinct symbiont types

    NASA Astrophysics Data System (ADS)

    Fisher, P. L.; Malme, M. K.; Dove, S.

    2012-06-01

    Several studies have demonstrated that the temperature tolerance of scleractinian reef-building corals is controlled, in part, by hosting physiologically distinct symbiotic algae. We investigated the thermal tolerance of coral-algal associations within seven common species of reef-building corals hosting distinct Symbiodinium sub-clades collected from Heron Island during experimentally induced bleaching conditions. During experimental heating, photosynthetic fitness was assessed by the dark-adapted yield of PSII ( F v/ F m), and excitation pressure across PSII ( Q m) of each coral-algal association using pulse amplitude modulation fluorometry. The onset of bleaching was determined by the measurement of Symbiodinium cell density. Using the ribosomal internal transcribed spacer 2 (ITS-2) region, we showed that Symbiodinium type-coral host associations were temporally and spatially conserved in a high proportion of the colonies sampled within each species. Generally, the species Acropora millepora, Platygyra daedalea, Acropora aspera and Acropora formosa contained Symbiodinium ITS-2 type C3, whereas the species Montipora digitata, Porites cylindrica and Porites lutea contained Symbiodinium type C15. Bleaching susceptibility showed some association with Symbiodinium type, but further research is required to confirm this. Corals hosting C3 Symbiodinium displayed higher reductions in F v/ F m during heating compared to their C15 counterparts, irrespective of host species. However, a corresponding reduction in Symbiodinium density was not observed. Nonetheless, A. aspera and A. formosa showed significant reductions in Symbiodinium density relative to controls. This correlated with large increases in Q m and decreases in F v/ F m in heated explants. Our results suggest a range of bleaching susceptibilities for the coral species investigated, with A. aspera and A. formosa showing the greatest susceptibility to bleaching and M. digitata showing the lowest bleaching

  14. Short and long term toxicity of crude oil and oil dispersants to two representative coral species.

    PubMed

    Shafir, Shai; Van Rijn, Jaap; Rinkevich, Baruch

    2007-08-01

    Oil dispersants, the tool of choice for treating oil spills in tropical marine environments, is potentially harmful to marine life, including reef corals. In a previous study, we found that dispersed oil and oil dispersants are harmful to soft and hard coral species at early life stages. In this broader study, we employed a "nubbin assay" on more than 10 000 coral fragments to evaluate the short- and long-term impacts of dispersed oil fractions (DOFs) from six commercial dispersants, the dispersants and water-soluble-fractions (WSFs) of Egyptian crude oil, on two Indo Pacific branching coral species, Stylophora pistillata and Pocillopora damicornis. Survivorship and growth of nubbins were recorded for up to 50 days following a single, short (24 h) exposure to toxicants in various concentrations. Manufacturer-recommended dispersant concentrations proved to be highly toxic and resulted in mortality for all nubbins. The dispersed oil and the dispersants were significantly more toxic than crude oil WSFs. As corals are particularly susceptible to oil detergents and dispersed oil, the results of these assays rules out the use of any oil dispersant in coral reefs and in their vicinity. The ecotoxicological impacts of the various dispersants on the corals could be rated on a scale from the least to the most harmful agent, as follows: Slickgone > Petrotech > Inipol = Biorieco > Emulgal > Dispolen.

  15. Short-term coral bleaching is not recorded by skeletal boron isotopes.

    PubMed

    Schoepf, Verena; McCulloch, Malcolm T; Warner, Mark E; Levas, Stephen J; Matsui, Yohei; Aschaffenburg, Matthew D; Grottoli, Andréa G

    2014-01-01

    Coral skeletal boron isotopes have been established as a proxy for seawater pH, yet it remains unclear if and how this proxy is affected by seawater temperature. Specifically, it has never been directly tested whether coral bleaching caused by high water temperatures influences coral boron isotopes. Here we report the results from a controlled bleaching experiment conducted on the Caribbean corals Porites divaricata, Porites astreoides, and Orbicella faveolata. Stable boron (δ11B), carbon (δ13C), oxygen (δ18O) isotopes, Sr/Ca, Mg/Ca, U/Ca, and Ba/Ca ratios, as well as chlorophyll a concentrations and calcification rates were measured on coral skeletal material corresponding to the period during and immediately after the elevated temperature treatment and again after 6 weeks of recovery on the reef. We show that under these conditions, coral bleaching did not affect the boron isotopic signature in any coral species tested, despite significant changes in coral physiology. This contradicts published findings from coral cores, where significant decreases in boron isotopes were interpreted as corresponding to times of known mass bleaching events. In contrast, δ13C and δ18O exhibited major enrichment corresponding to decreases in calcification rates associated with bleaching. Sr/Ca of bleached corals did not consistently record the 1.2°C difference in seawater temperature during the bleaching treatment, or alternatively show a consistent increase due to impaired photosynthesis and calcification. Mg/Ca, U/Ca, and Ba/Ca were affected by coral bleaching in some of the coral species, but the observed patterns could not be satisfactorily explained by temperature dependence or changes in coral physiology. This demonstrates that coral boron isotopes do not record short-term bleaching events, and therefore cannot be used as a proxy for past bleaching events. The robustness of coral boron isotopes to changes in coral physiology, however, suggests that reconstruction of

  16. Short-Term Coral Bleaching Is Not Recorded by Skeletal Boron Isotopes

    PubMed Central

    Schoepf, Verena; McCulloch, Malcolm T.; Warner, Mark E.; Levas, Stephen J.; Matsui, Yohei; Aschaffenburg, Matthew D.; Grottoli, Andréa G.

    2014-01-01

    Coral skeletal boron isotopes have been established as a proxy for seawater pH, yet it remains unclear if and how this proxy is affected by seawater temperature. Specifically, it has never been directly tested whether coral bleaching caused by high water temperatures influences coral boron isotopes. Here we report the results from a controlled bleaching experiment conducted on the Caribbean corals Porites divaricata, Porites astreoides, and Orbicella faveolata. Stable boron (δ11B), carbon (δ13C), oxygen (δ18O) isotopes, Sr/Ca, Mg/Ca, U/Ca, and Ba/Ca ratios, as well as chlorophyll a concentrations and calcification rates were measured on coral skeletal material corresponding to the period during and immediately after the elevated temperature treatment and again after 6 weeks of recovery on the reef. We show that under these conditions, coral bleaching did not affect the boron isotopic signature in any coral species tested, despite significant changes in coral physiology. This contradicts published findings from coral cores, where significant decreases in boron isotopes were interpreted as corresponding to times of known mass bleaching events. In contrast, δ13C and δ18O exhibited major enrichment corresponding to decreases in calcification rates associated with bleaching. Sr/Ca of bleached corals did not consistently record the 1.2°C difference in seawater temperature during the bleaching treatment, or alternatively show a consistent increase due to impaired photosynthesis and calcification. Mg/Ca, U/Ca, and Ba/Ca were affected by coral bleaching in some of the coral species, but the observed patterns could not be satisfactorily explained by temperature dependence or changes in coral physiology. This demonstrates that coral boron isotopes do not record short-term bleaching events, and therefore cannot be used as a proxy for past bleaching events. The robustness of coral boron isotopes to changes in coral physiology, however, suggests that reconstruction of

  17. Variation in oxygen isotope ratio of dissolved orthophosphate induced by uptake process in natural coral holobionts

    NASA Astrophysics Data System (ADS)

    Ferrera, Charissa M.; Miyajima, Toshihiro; Watanabe, Atsushi; Umezawa, Yu; Morimoto, Naoko; San Diego-McGlone, Maria Lourdes; Nadaoka, Kazuo

    2016-06-01

    A model incubation experiment using natural zooxanthellate corals was conducted to evaluate the influence of phosphate uptake by coral holobionts on oxygen isotope ratio of dissolved PO4 3- (δ18Op). Live coral samples of Acropora digitifera, Porites cylindrica, and Heliopora coerulea were collected from coral reefs around Ishigaki Island (Okinawa, Japan) and Bolinao (northern Luzon, Philippines) and incubated for 3-5 d after acclimatization under natural light conditions with elevated concentrations of PO4 3-. Phosphate uptake by corals behaved linearly with incubation time, with uptake rate depending on temperature. δ18Op usually increased with time toward the equilibrium value with respect to oxygen isotope exchange with ambient seawater, but sometimes became higher than equilibrium value at the end of incubation. The magnitude of the isotope effect associated with uptake depended on coral species; the greatest effect was in A. digitifera and the smallest in H. coerulea. However, it varied even within samples of a single coral species, which suggests multiple uptake processes with different isotope effects operating simultaneously with varying relative contributions in the coral holobionts used. In natural environments where concentrations of PO4 3- are much lower than those used during incubation, PO4 3- is presumably turned over much faster and the δ18Op easily altered by corals and other major primary producers. This should be taken into consideration when using δ18Op as an indicator of external PO4 3- sources in coastal ecosystems.

  18. Evaluating life-history strategies of reef corals from species traits.

    PubMed

    Darling, Emily S; Alvarez-Filip, Lorenzo; Oliver, Thomas A; McClanahan, Timothy R; Côté, Isabelle M; Bellwood, David

    2012-12-01

    Classifying the biological traits of organisms can test conceptual frameworks of life-history strategies and allow for predictions of how different species may respond to environmental disturbances. We apply a trait-based classification approach to a complex and threatened group of species, scleractinian corals. Using hierarchical clustering and random forests analyses, we identify up to four life-history strategies that appear globally consistent across 143 species of reef corals: competitive, weedy, stress-tolerant and generalist taxa, which are primarily separated by colony morphology, growth rate and reproductive mode. Documented shifts towards stress-tolerant, generalist and weedy species in coral reef communities are consistent with the expected responses of these life-history strategies. Our quantitative trait-based approach to classifying life-history strategies is objective, applicable to any taxa and a powerful tool that can be used to evaluate theories of community ecology and predict the impact of environmental and anthropogenic stressors on species assemblages.

  19. Temporal comparison and predictors of fish species abundance and richness on undisturbed coral reef patches.

    PubMed

    Wagner, Elena L E S; Roche, Dominique G; Binning, Sandra A; Wismer, Sharon; Bshary, Redouan

    2015-01-01

    Large disturbances can cause rapid degradation of coral reef communities, but what baseline changes in species assemblages occur on undisturbed reefs through time? We surveyed live coral cover, reef fish abundance and fish species richness in 1997 and again in 2007 on 47 fringing patch reefs of varying size and depth at Mersa Bareika, Ras Mohammed National Park, Egypt. No major human or natural disturbance event occurred between these two survey periods in this remote protected area. In the absence of large disturbances, we found that live coral cover, reef fish abundance and fish species richness did not differ in 1997 compared to 2007. Fish abundance and species richness on patches was largely related to the presence of shelters (caves and/or holes), live coral cover and patch size (volume). The presence of the ectoparasite-eating cleaner wrasse, Labroides dimidiatus, was also positively related to fish species richness. Our results underscore the importance of physical reef characteristics, such as patch size and shelter availability, in addition to biotic characteristics, such as live coral cover and cleaner wrasse abundance, in supporting reef fish species richness and abundance through time in a relatively undisturbed and understudied region.

  20. Allelochemicals Produced by Brown Macroalgae of the Lobophora Genus Are Active against Coral Larvae and Associated Bacteria, Supporting Pathogenic Shifts to Vibrio Dominance.

    PubMed

    Morrow, Kathleen M; Bromhall, Katrina; Motti, Cherie A; Munn, Colin B; Bourne, David G

    2017-01-01

    Pervasive environmental stressors on coral reefs are attributed with shifting the competitive balance in favor of alternative dominants, such as macroalgae. Previous studies have demonstrated that macroalgae compete with corals via a number of mechanisms, including the production of potent primary and secondary metabolites that can influence coral-associated microbial communities. The present study investigates the effects of the Pacific brown macroalga Lobophora sp. (due to the shifting nature of the Lobophora species complex, it will be referred to here as Lobophora sp.) on coral bacterial isolates, coral larvae, and the microbiome associated with the coral Porites cylindrica. Crude aqueous and organic macroalgal extracts were found to inhibit the growth of coral-associated bacteria. Extracts and fractions were also shown to inhibit coral larval settlement and cause mortality at concentrations lower (<0.3 mg · ml(-1)) than calculated natural concentrations (4.4 mg · ml(-1)). Microbial communities associated with coral tissues exposed to aqueous (e.g., hydrophilic) crude extracts demonstrated a significant shift to Vibrio dominance and a loss of sequences related to the putative coral bacterial symbiont, Endozoicomonas sp., based on 16S rRNA amplicon sequencing. This study contributes to growing evidence that macroalgal allelochemicals, dissolved organic material, and native macroalgal microbial assemblages all play a role in shifting the microbial equilibrium of the coral holobiont away from a beneficial state, contributing to a decline in coral fitness and a shift in ecosystem structure.

  1. Low symbiont diversity as a potential adaptive strategy in a marginal non-reefal environment: a case study of corals in Hong Kong

    NASA Astrophysics Data System (ADS)

    Ng, Tsz Yan; Ang, Put

    2016-09-01

    Symbiosis with genetically diverse Symbiodinium has been shown to affect host coral physiological responses to environmental stresses. Hong Kong, located in a subtropical region, is a marginal environment for coral growth largely due to its wide annual temperature fluctuation with low mean winter sea water temperature (~16 °C) and variable salinity conditions. The symbiont diversity in Hong Kong corals is therefore worth investigating to enrich our understanding on symbioses in marginal and fluctuating environments. Examination of 56 scleractinian coral species and five soft coral species using denaturing gel gradient electrophoresis of the internal transcribed spacer region 2 found only five distinct subclades of Symbiodinium with C1 the dominant type occurring in all but one scleractinian coral and all soft coral species investigated. C15 and C21 Symbiodinium were found in Porites spp. and Montipora peltiformis, respectively, both of which are vertical transmitters. D8-12 was found in Oulastrea crispata, a stress-tolerant species, and D1 in a single sample of Goniastrea aspera. No spatial differences in Symbiodinium composition were found among different regions of Hong Kong. Seasonal monitoring of tagged Platygyra acuta and Porites spp. colonies also revealed no changes in their symbiont types despite wide ranges of in situ temperature fluctuation. Hong Kong scleractinian corals hosted a remarkably low symbiont diversity compared with corals in the surrounding regions. The predominance of a single subclade, C1 Symbiodinium, suggests that this subclade is best acclimatized to local fluctuating conditions and/or low winter temperature. Forming symbiosis with the best acclimatized symbiont, instead of with a diverse group of symbionts with different physiological performances, either sequentially or simultaneously, may be a strategy used by Hong Kong corals to cope with stressful conditions.

  2. Ecological variables, including physiognomic-structural attributes, and classification of Indonesian coral reefs

    NASA Astrophysics Data System (ADS)

    Bak, R. P. M.; Povel, G. D. E.

    Communities are distinguished by biological and physical features, such as size and shape of organisms and dead substrata, which are characteristic expressions of the organizing forces in the community. We measured 87 of such features in 39 transects on seaward-facing reef slopes in the eastern Indonesian archipelago, but did not identify coral species. We aimed to identify the basic variables that are indispensable to classify coral reef communities. This would give ecological information on variation in reef communities and show exactly which data must be recorded in the field. Principal Component Analysis (PCA) of the data matrix showed the following variables to be important in the ordination of transects along the axes: coral colony shape, loose fragments, bare bottom, coral tissue wounds, rubble, sediment/rubble, crustose coralline algae, excavating sponge, miscellaneous organisms, coral overgrowth, interaction coral/non-coral, Acanthaster, maximum size coral colonies, tabular Acropora, massive Porites, fungiids, angle slope, and crevices. We used the transect data to define four groups of environmental conditions: 'sheltered', 'exposed' (to water movement), 'biologically disturbed' and 'physically disturbed'. Discriminant Analysis was employed to classify additional transects. It appeared that a minimum of 9 variables has to be measured in the field (rubble, thick branching corals, fungiids, sediment/rubble, two largest-colonies diameters, massive Porites, angle slope, Acanthaster) to assign transects to one of those groups (P < 0.10). With just 14 variables the classification of transects was 100% correct. Two additional groups of environmental conditions are recognizable with, respectively, prominence of competitive interactions and Acanthaster predation. There were too few transect data to characterize these groups satisfactorily for Discriminant Analysis.

  3. The ploys of sex: relationships among the mode of reproduction, body size and habitats of coral-reef brittlestars

    NASA Astrophysics Data System (ADS)

    Hendler, Gordon; Littman, Barbara S.

    1986-08-01

    Observations were made of 33 species of brittlestars (3980 specimens) from specific substrata collected in four zones on the Belize Barrier Reef, Caribbean Sea. The body size of most species of brittlestars with planktonic larvae differs significantly among different substrata. Generally, individuals from the calcareous alga Halimeda opuntia are smallest, those found in corals ( Porites porites, Madracis mirabilis, and Agaricia tenuifolia) are larger, and those from coral rubble are the largest. This suggests that brittlestars with planktonic larvae move to new microhabitats as they grow. In contrast, most brooding and fissiparous species are relatively small and their size-distributions are similar among all substrata. Halimeda harbours denser concentrations of brittlestars and more small and juvenile individuals than the other substrata. Juveniles of the brooding and fissiparous species are most common in Halimeda on the Back Reef whereas juveniles developing from planktonic larvae are most common in Halimeda patches in deeper water. Fissiparity and brooding may be means for individuals (genomes) of small, apomictic species to reach large size (and correspondingly high fecundities) in patchy microhabitats that select for small body sizes. Small brittlestar species and juveniles are most numerous in the microhabitats called refuge-substrata, such as Halimeda, which may repel predators and reduce environmental stress. Whether young brittlestars are concentrated in refuge-substrata through settlement behavior, migration, or differential survival remains unknown. Experiments revealed that coral polyps kill small brittlestars, perhaps accounting for the rarity of small and juvenile brittlestars in coral substrata.

  4. Coral distribution patterns in Miocene Reefs of Anguilla, Leeward Islands, West Indies

    SciTech Connect

    Foster, A.B.; Johnson, K.G.

    1988-01-01

    Anguilla, a 27 by 5 km island at 18/sup 0/13'N, 63/sup 0/05'W, parallels the northwest edge of the Anguilla bank (St. Martin plateau) in the outer lesser Angilles volcanic arc, which was active from the Eocene to Oligocene. Except for scattered exposures of tuff or basalt, the island is composed predominantly of reefal limestones and marls of the 70-m thick, middle Miocene Anguilla Formation, deposited on a shallow inner shelf platform extending from volcanoes near St. Martin. The reef framework consists of branched and platy corals interspersed with calcareous sand lenses. Although the limestones have been uplifted and subjected to minor faulting, little evidence supports extensive transport across a slope. Coral distribution patterns have been quantified across the reefal units by point-counting species occurrences at 0.16-m intervals within 1-m/sup 2/ quadrants placed haphazardly across vertical exposures. Eight coral species (of possibly 18 total) were recorded. Cluster analysis delineated four facies: (1) a low-diversity facies dominated by branched Porites, (2) an intermediate diversity facies dominated by branched Porites, (3) a high-diversity facies dominated by massive Montastraea, Siderastrea, and Porites, and (4) an intermediate diversity facies dominated by platy Porites. These facies consists of lenses, no more than 100 m long and 2 m high, arranged in no apparent regular sequence. Thus, they do not represent zones across a depth gradient. Comparisons with living Caribbean reefs suggests that the Anguilla Miocene reefs were similar to small, modern, backreef fringing and patch reefs near the San Blas Islands of Panama, reefs whose variable composition and patchy distribution depend largely on sedimentation and current patterns.

  5. Reduced calcification and lack of acclimatization by coral colonies growing in areas of persistent natural acidification.

    PubMed

    Crook, Elizabeth D; Cohen, Anne L; Rebolledo-Vieyra, Mario; Hernandez, Laura; Paytan, Adina

    2013-07-02

    As the surface ocean equilibrates with rising atmospheric CO2, the pH of surface seawater is decreasing with potentially negative impacts on coral calcification. A critical question is whether corals will be able to adapt or acclimate to these changes in seawater chemistry. We use high precision CT scanning of skeletal cores of Porites astreoides, an important Caribbean reef-building coral, to show that calcification rates decrease significantly along a natural gradient in pH and aragonite saturation (Ωarag). This decrease is accompanied by an increase in skeletal erosion and predation by boring organisms. The degree of sensitivity to reduced Ωarag measured on our field corals is consistent with that exhibited by the same species in laboratory CO2 manipulation experiments. We conclude that the Porites corals at our field site were not able to acclimatize enough to prevent the impacts of local ocean acidification on their skeletal growth and development, despite spending their entire lifespan in low pH, low Ωarag seawater.

  6. Reduced calcification and lack of acclimatization by coral colonies growing in areas of persistent natural acidification

    PubMed Central

    Crook, Elizabeth D.; Cohen, Anne L.; Rebolledo-Vieyra, Mario; Hernandez, Laura; Paytan, Adina

    2013-01-01

    As the surface ocean equilibrates with rising atmospheric CO2, the pH of surface seawater is decreasing with potentially negative impacts on coral calcification. A critical question is whether corals will be able to adapt or acclimate to these changes in seawater chemistry. We use high precision CT scanning of skeletal cores of Porites astreoides, an important Caribbean reef-building coral, to show that calcification rates decrease significantly along a natural gradient in pH and aragonite saturation (Ωarag). This decrease is accompanied by an increase in skeletal erosion and predation by boring organisms. The degree of sensitivity to reduced Ωarag measured on our field corals is consistent with that exhibited by the same species in laboratory CO2 manipulation experiments. We conclude that the Porites corals at our field site were not able to acclimatize enough to prevent the impacts of local ocean acidification on their skeletal growth and development, despite spending their entire lifespan in low pH, low Ωarag seawater. PMID:23776217

  7. Variability in the Effects of Macroalgae on the Survival and Growth of Corals: The Consumer Connection

    PubMed Central

    Bulleri, Fabio; Couraudon-Réale, Marine; Lison de Loma, Thierry; Claudet, Joachim

    2013-01-01

    Shifts in dominance from corals to macroalgae are occurring in many coral reefs worldwide. Macroalgal canopies, while competing for space with coral colonies, may also form a barrier to herbivorous and corallivorous fish, offering protection to corals. Thus, corals could either suffer from enhanced competition with canopy-forming and understorey macroalgae or benefit from predator exclusion. Here, we tested the hypothesis that the effects of the brown, canopy-forming macroalga, Turbinaria ornata, on the survival and growth of corals can vary according to its cover, to the presence or absence of herbivorous and corallivorous fish and to the morphological types of corals. Over a period of 66 days, two coral species differing in growth form, Acropora pulchra and Porites rus, were exposed to three different covers of T. ornata (absent versus medium versus high), in the presence or absence of fish. Irrespective of the cover of T. ornata, fish exclusion reduced mortality rates of A. pulchra. Following fish exclusion, a high cover of T. ornata depressed the growth of this branched coral, whilst it had no effect when fish species were present. P. rus suffered no damage from corallivorous fish, but its growth was decreased by high covers of T. ornata, irrespective of the presence or absence of fish. These results show that negative effects of T. ornata on some coral species are subordinate to those of fish predation and are, therefore, likely to manifest only on reefs severely depleted of predators. In contrast, space dominance by T. ornata may decrease the growth of other coral species regardless of predation intensity. In general, this study shows that susceptibility to predation may determine the severity of the effects of canopy-forming macroalgae on coral growth. PMID:24260290

  8. Comparing Environmental Influences on Coral Bleaching Across and within Species using Clustered Binomial Regression

    EPA Science Inventory

    Differential susceptibility among reef-building coral species can lead to community shifts and loss of diversity as a result of temperature-induced mass bleaching events. However, the influence of the local environment on species-specific bleaching susceptibilities has not been ...

  9. Optimal choice of species and size class for transplanting coral community.

    PubMed

    Muko, Soyoka; Iwasa, Yoh

    2011-03-21

    Transplantation of sessile organisms living in a planned destruction site to a safe site is an important means of restoration to mitigate biodiversity loss following anthropogenic developments. In particular, corals, which play fundamental roles in the coral reef ecosystem and contribute to biodiversity, are good candidates for transplantation. In this study, we investigate the optimal choice of species and size class to be used for coral transplantation. We first studied a case in which the objective function to evaluate the success of transplantation is the maximum total coverage. The optimal strategy is to choose the species and size class with higher net coverage gain per unit handling effort. It is often recommended to transplant only one or a few species and neglect others, even if the original community consists of many species. This may achieve high coverage in the restored coral community but cause loss of species diversity. To overcome this problem, we next study a case in which the objective of the transplantation operation is to maximize the "prosperity index", defined as the product of total coverage and species diversity. In this case, the optimal strategy depends on the species property, population size, and the limitation of total cost allowed for transplantation, but it tends to recommend more species to be transplanted than what is recommended by the coverage maximization criterion. We conclude that maximization of the prosperity index is a better criterion for transplantation than simple coverage maximization.

  10. Considering Species Tolerance to Climate Change in Conservation Management at Little Cayman's Coral Reefs

    NASA Astrophysics Data System (ADS)

    Camp, E.; Manfrino, C.; Smith, D.; Suggett, D.

    2013-05-01

    There is growing evidence demonstrating that climate change, notably increased frequency and intensity of thermal anomalies combined with ocean acidification, will negatively impact the future growth and viability of many reef systems, including those in the Caribbean. One key question that remains unanswered is whether or not there are management options aimed at protecting coral species from these threats. Little Cayman (Cayman Islands) provides a rare opportunity to investigate global climate stressors without the confounding impact of local anthropogenic stressors. Our research has focused on two climate change issues: Firstly, we have identified species-specific coral bleaching susceptibility (and the influence of regulation upon this susceptibility) to thermal anomalies. Species level of vulnerability to thermal anomalies can decrease when grown under variable temperature. Environmental variability may be key in influencing the susceptibility of corals to stress. The second part of our research has therefore addressed the variability in inorganic carbon chemistry that naturally occurs where certain reef building corals exist. We have identified how the inorganic carbon chemistry varies naturally among habitats and thus how corals within these habitats are potentially adapted to future acidification. Spatial, diurnal, lunar and seasonal variability have been identified as important factors with pCO2 values of up to 700-800 μatm and pH values as low as 7.801 for lagoon habitats, showing that some species are already being exposed to typical pCO2 and pH levels expected for the oceans in ~50 years' time. Using an eco-physiological approach, we are exploring how some reef-building corals are able to acclimate to more variable chemistry compared to others and whether this natural capacity installs increased tolerance to future acidification. These eco-physiological studies provide important information that can be utilized in a management framework. The aim of

  11. Deep reefs are not universal refuges: Reseeding potential varies among coral species

    PubMed Central

    Bongaerts, Pim; Riginos, Cynthia; Brunner, Ramona; Englebert, Norbert; Smith, Struan R.; Hoegh-Guldberg, Ove

    2017-01-01

    Deep coral reefs (that is, mesophotic coral ecosystems) can act as refuges against major disturbances affecting shallow reefs. It has been proposed that, through the provision of coral propagules, such deep refuges may aid in shallow reef recovery; however, this “reseeding” hypothesis remains largely untested. We conducted a genome-wide assessment of two scleractinian coral species with contrasting reproductive modes, to assess the potential for connectivity between mesophotic (40 m) and shallow (12 m) depths on an isolated reef system in the Western Atlantic (Bermuda). To overcome the pervasive issue of endosymbiont contamination associated with de novo sequencing of corals, we used a novel subtraction reference approach. We have demonstrated that strong depth-associated selection has led to genome-wide divergence in the brooding species Agaricia fragilis (with divergence by depth exceeding divergence by location). Despite introgression from shallow into deep populations, a lack of first-generation migrants indicates that effective connectivity over ecological time scales is extremely limited for this species and thus precludes reseeding of shallow reefs from deep refuges. In contrast, no genetic structuring between depths (or locations) was observed for the broadcasting species Stephanocoenia intersepta, indicating substantial potential for vertical connectivity. Our findings demonstrate that vertical connectivity within the same reef system can differ greatly between species and that the reseeding potential of deep reefs in Bermuda may apply to only a small number of scleractinian species. Overall, we argue that the “deep reef refuge hypothesis” holds for individual coral species during episodic disturbances but should not be assumed as a broader ecosystem-wide phenomenon. PMID:28246645

  12. Deep reefs are not universal refuges: Reseeding potential varies among coral species.

    PubMed

    Bongaerts, Pim; Riginos, Cynthia; Brunner, Ramona; Englebert, Norbert; Smith, Struan R; Hoegh-Guldberg, Ove

    2017-02-01

    Deep coral reefs (that is, mesophotic coral ecosystems) can act as refuges against major disturbances affecting shallow reefs. It has been proposed that, through the provision of coral propagules, such deep refuges may aid in shallow reef recovery; however, this "reseeding" hypothesis remains largely untested. We conducted a genome-wide assessment of two scleractinian coral species with contrasting reproductive modes, to assess the potential for connectivity between mesophotic (40 m) and shallow (12 m) depths on an isolated reef system in the Western Atlantic (Bermuda). To overcome the pervasive issue of endosymbiont contamination associated with de novo sequencing of corals, we used a novel subtraction reference approach. We have demonstrated that strong depth-associated selection has led to genome-wide divergence in the brooding species Agaricia fragilis (with divergence by depth exceeding divergence by location). Despite introgression from shallow into deep populations, a lack of first-generation migrants indicates that effective connectivity over ecological time scales is extremely limited for this species and thus precludes reseeding of shallow reefs from deep refuges. In contrast, no genetic structuring between depths (or locations) was observed for the broadcasting species Stephanocoenia intersepta, indicating substantial potential for vertical connectivity. Our findings demonstrate that vertical connectivity within the same reef system can differ greatly between species and that the reseeding potential of deep reefs in Bermuda may apply to only a small number of scleractinian species. Overall, we argue that the "deep reef refuge hypothesis" holds for individual coral species during episodic disturbances but should not be assumed as a broader ecosystem-wide phenomenon.

  13. Species delimitation in the reef coral genera Echinophyllia and Oxypora (Scleractinia, Lobophylliidae) with a description of two new species.

    PubMed

    Arrigoni, Roberto; Berumen, Michael L; Chen, Chaolun Allen; Terraneo, Tullia I; Baird, Andrew H; Payri, Claude; Benzoni, Francesca

    2016-12-01

    Scleractinian corals are affected by environment-induced phenotypic plasticity and intraspecific morphological variation caused by genotype. In an effort to identify new strategies for resolving this taxonomic issue, we applied a molecular approach for species evaluation to two closely related genera, Echinophyllia and Oxypora, for which few molecular data are available. A robust multi-locus phylogeny using DNA sequence data across four loci of both mitochondrial (COI, ATP6-NAD4) and nuclear (histone H3, ITS region) origin from 109 coral colonies was coupled with three independent putative species delimitation methods based on barcoding threshold (ABGD) and coalescence theory (PTP, GMYC). Observed overall congruence across multiple genetic analyses distinguished two traditional species (E. echinoporoides and O. convoluta), a species complex composed of E. aspera, E. orpheensis, E. tarae, and O. glabra, whereas O. lacera and E. echinata were indistinguishable with the sequenced loci. The combination of molecular species delimitation approaches and skeletal character observations allowed the description of two new reef coral species, E. bulbosa sp. n. from the Red Sea and E. gallii sp. n. from the Maldives and Mayotte. This work demonstrated the efficiency of multi-locus phylogenetic analyses and recently developed molecular species delimitation approaches as valuable tools to disentangle taxonomic issues caused by morphological ambiguities and to re-assess the diversity of scleractinian corals.

  14. Coral reef recovery status in south Andaman Islands after the bleaching event 2010

    NASA Astrophysics Data System (ADS)

    Marimuthu, N.; Jerald Wilson, J.; Vinithkumar, N. V.; Kirubagaran, R.

    2013-03-01

    The Andaman and Nicobar Islands are one of the Union Territories of India, located in the eastern part of the Bay of Bengal. In 2010 summer, the increment in sea surface water temperature (up to 34°C) resulted in the bleaching of about 74% to 77% of corals in the South Andaman. During this event, coral species such as Acropora cerealis, A. humilis, Montipora sp., Favia pallida, Diploastrea sp., Goniopora sp. Fungia concinna, Gardineroseries sp., Porites sp., Favites abdita and Lobophyllia robusta were severely affected. This study is to assess the recovery status of the reef ecosystem by estimating the percentage of Live Coral cover, Bleached coral cover, Dead coral with algae, Rubble, Sandy flat, Algal assemblage and other associated organisms. The sedimentation rate (mg cm-2 d-1) and coral coverage (%) were assessed during this study period. The average sedimentation rate was ranged between 0.27 and 0.89 mg cm-2 d-1. The observed post bleaching recovery of coral cover was 21.1% at Port Blair Bay and 13.29% at Havelock Island. The mortality rate of coral cover due to this bleaching was estimated as 2.05% at Port Blair Bay and 9.82% at Havelock Island. Once the sea water temperature resumed back to the normal condition, most of the corals were found recovered.

  15. Large predatory coral trout species unlikely to meet increasing energetic demands in a warming ocean

    PubMed Central

    Johansen, J.L.; Pratchett, M.S.; Messmer, V.; Coker, D.J.; Tobin, A.J.; Hoey, A.S.

    2015-01-01

    Increased ocean temperature due to climate change is raising metabolic demands and energy requirements of marine ectotherms. If productivity of marine systems and fisheries are to persist, individual species must compensate for this demand through increasing energy acquisition or decreasing energy expenditure. Here we reveal that the most important coral reef fishery species in the Indo-west Pacific, the large predatory coral trout Plectropomus leopardus (Serranidae), can behaviourally adjust food intake to maintain body-condition under elevated temperatures, and acclimate over time to consume larger meals. However, these increased energetic demands are unlikely to be met by adequate production at lower trophic levels, as smaller prey species are often the first to decline in response to climate-induced loss of live coral and structural complexity. Consequently, ubiquitous increases in energy consumption due to climate change will increase top-down competition for a dwindling biomass of prey, potentially distorting entire food webs and associated fisheries. PMID:26345733

  16. Evolutionary novelty is concentrated at the edge of coral species distributions.

    PubMed

    Budd, Ann F; Pandolfi, John M

    2010-06-18

    Conservation priorities are calculated on the basis of species richness, endemism, and threats. However, areas ranked highly for these factors may not represent regions of maximal evolutionary potential. The relationship between geography and evolutionary innovation was analyzed in a dominant complex of Caribbean reef corals, in which morphological and genetic data concur on species differences. Based on geometric morphometrics of Pleistocene corals and genetically characterized modern colonies, we found that morphological disparity varies from the center to the edge of the Caribbean, and we show that lineages are static at well-connected central locations but split or fuse in edge zones where gene flow is limited. Thus, conservation efforts in corals should focus not only on the centers of diversity but also on peripheral areas of species ranges and population connectivity.

  17. Large predatory coral trout species unlikely to meet increasing energetic demands in a warming ocean.

    PubMed

    Johansen, J L; Pratchett, M S; Messmer, V; Coker, D J; Tobin, A J; Hoey, A S

    2015-09-08

    Increased ocean temperature due to climate change is raising metabolic demands and energy requirements of marine ectotherms. If productivity of marine systems and fisheries are to persist, individual species must compensate for this demand through increasing energy acquisition or decreasing energy expenditure. Here we reveal that the most important coral reef fishery species in the Indo-west Pacific, the large predatory coral trout Plectropomus leopardus (Serranidae), can behaviourally adjust food intake to maintain body-condition under elevated temperatures, and acclimate over time to consume larger meals. However, these increased energetic demands are unlikely to be met by adequate production at lower trophic levels, as smaller prey species are often the first to decline in response to climate-induced loss of live coral and structural complexity. Consequently, ubiquitous increases in energy consumption due to climate change will increase top-down competition for a dwindling biomass of prey, potentially distorting entire food webs and associated fisheries.

  18. Seaweed-coral interactions: variance in seaweed allelopathy, coral susceptibility, and potential effects on coral resilience.

    PubMed

    Bonaldo, Roberta M; Hay, Mark E

    2014-01-01

    Tropical reefs are in global decline with seaweeds commonly replacing corals. Negative associations between macroalgae and corals are well documented, but the mechanisms involved, the dynamics of the interactions, and variance in effects of different macroalgal-coral pairings are poorly investigated. We assessed the frequency, magnitude, and dynamics of macroalgal-coral competition involving allelopathic and non-allelopathic macroalgae on three, spatially grouped pairs of no-take Marine Protected Areas (MPAs) and non-MPAs in Fiji. In non-MPAs, biomass of herbivorous fishes was 70-80% lower, macroalgal cover 4-9 fold higher, macroalgal-coral contacts 5-15 fold more frequent and 23-67 fold more extensive (measured as % of colony margin contacted by macroalgae), and coral cover 51-68% lower than in MPAs. Coral contacts with allelopathic macroalgae occurred less frequently than expected by chance across all sites, while contact with non-allelopathic macroalgae tended to occur more frequently than expected. Transplants of allelopathic macroalgae (Chlorodesmis fastigiata and Galaxaura filamentosa) against coral edges inflicted damage to Acropora aspera and Pocillopora damicornis more rapidly and extensively than to Porites cylindrica and Porites lobata, which appeared more resistant to these macroalgae. Montipora digitata experienced intermediate damage. Extent of damage from macroalgal contact was independent of coral colony size for each of the 10 macroalgal-coral pairings we established. When natural contacts with Galaxaura filamentosa were removed in the field, recovery was rapid for Porites lobata, but Pocillopora damicornis did not recover and damage continued to expand. As macroalgae increase on overfished tropical reefs, allelopathy could produce feedbacks that suppress coral resilience, prevent coral recovery, and promote the stability of algal beds in habitats previously available to corals.

  19. Seaweed-Coral Interactions: Variance in Seaweed Allelopathy, Coral Susceptibility, and Potential Effects on Coral Resilience

    PubMed Central

    Bonaldo, Roberta M.; Hay, Mark E.

    2014-01-01

    Tropical reefs are in global decline with seaweeds commonly replacing corals. Negative associations between macroalgae and corals are well documented, but the mechanisms involved, the dynamics of the interactions, and variance in effects of different macroalgal-coral pairings are poorly investigated. We assessed the frequency, magnitude, and dynamics of macroalgal-coral competition involving allelopathic and non-allelopathic macroalgae on three, spatially grouped pairs of no-take Marine Protected Areas (MPAs) and non-MPAs in Fiji. In non-MPAs, biomass of herbivorous fishes was 70–80% lower, macroalgal cover 4–9 fold higher, macroalgal-coral contacts 5–15 fold more frequent and 23–67 fold more extensive (measured as % of colony margin contacted by macroalgae), and coral cover 51–68% lower than in MPAs. Coral contacts with allelopathic macroalgae occurred less frequently than expected by chance across all sites, while contact with non-allelopathic macroalgae tended to occur more frequently than expected. Transplants of allelopathic macroalgae (Chlorodesmis fastigiata and Galaxaura filamentosa) against coral edges inflicted damage to Acropora aspera and Pocillopora damicornis more rapidly and extensively than to Porites cylindrica and Porites lobata, which appeared more resistant to these macroalgae. Montipora digitata experienced intermediate damage. Extent of damage from macroalgal contact was independent of coral colony size for each of the 10 macroalgal-coral pairings we established. When natural contacts with Galaxaura filamentosa were removed in the field, recovery was rapid for Porites lobata, but Pocillopora damicornis did not recover and damage continued to expand. As macroalgae increase on overfished tropical reefs, allelopathy could produce feedbacks that suppress coral resilience, prevent coral recovery, and promote the stability of algal beds in habitats previously available to corals. PMID:24465707

  20. Mesophotic depths as refuge areas for fishery-targeted species on coral reefs

    NASA Astrophysics Data System (ADS)

    Lindfield, Steven J.; Harvey, Euan S.; Halford, Andrew R.; McIlwain, Jennifer L.

    2016-03-01

    Coral reefs are subjected to unprecedented levels of disturbance with population growth and climate change combining to reduce standing coral cover and stocks of reef fishes. Most of the damage is concentrated in shallow waters (<30 m deep) where humans can comfortably operate and where physical disturbances are most disruptive to marine organisms. Yet coral reefs can extend to depths exceeding 100 m, potentially offering refuge from the threats facing shallower reefs. We deployed baited remote underwater stereo-video systems (stereo-BRUVs) at depths of 10-90 m around the southern Mariana Islands to investigate whether fish species targeted by fishing in the shallows may be accruing benefits from being at depth. We show that biomass, abundance and species richness of fishery-targeted species increased from shallow reef areas to a depth of 60 m, whereas at greater depths, a lack of live coral habitat corresponded to lower numbers of fish. The majority of targeted species were found to have distributions that ranged from shallow depths (10 m) to depths of at least 70 m, emphasising that habitat, not depth, is the limiting factor in their vertical distribution. While the gradient of abundance and biomass versus depth was steepest for predatory species, the first species usually targeted by fishing, we also found that fishery-targeted herbivores prevailed in similar biomass and species richness to 60 m. Compared to shallow marine protected areas, there was clearly greater biomass of fishery-targeted species accrued in mesophotic depths. Particularly some species typically harvested by depth-limited fishing methods (e.g., spearfishing), such as the endangered humphead wrasse Cheilinus undulatus, were found in greater abundance on deeper reefs. We conclude that mesophotic depths provide essential fish habitat and refuge for fishery-targeted species, representing crucial zones for fishery management and research into the resilience of disturbed coral reef ecosystems.

  1. Species richness on coral reefs and the pursuit of convergent global estimates.

    PubMed

    Fisher, Rebecca; O'Leary, Rebecca A; Low-Choy, Samantha; Mengersen, Kerrie; Knowlton, Nancy; Brainard, Russell E; Caley, M Julian

    2015-02-16

    Global species richness, whether estimated by taxon, habitat, or ecosystem, is a key biodiversity metric. Yet, despite the global importance of biodiversity and increasing threats to it (e.g., we are no better able to estimate global species richness now than we were six decades ago. Estimates of global species richness remain highly uncertain and are often logically inconsistent. They are also difficult to validate because estimation of global species richness requires extrapolation beyond the number of species known. Given that somewhere between 3% and >96% of species on Earth may remain undiscovered, depending on the methods used and the taxa considered, such extrapolations, especially from small percentages of known species, are likely to be highly uncertain. An alternative approach is to estimate all species, the known and unknown, directly. Using expert taxonomic knowledge of the species already described and named, those already discovered but not yet described and named, and those still awaiting discovery, we estimate there to be 830,000 (95% credible limits: 550,000-1,330,000) multi-cellular species on coral reefs worldwide, excluding fungi. Uncertainty surrounding this estimate and its components were often strongly skewed toward larger values, indicating that many more species on coral reefs is more plausible than many fewer. The uncertainties revealed here should guide future research toward achieving convergence in global species richness estimates for coral reefs and other ecosystems via adaptive learning protocols whereby such estimates can be tested and improved, and their uncertainties reduced, as new knowledge is acquired.

  2. Identity and diversity of coral endosymbionts (zooxanthellae) from three Palauan reefs with contrasting bleaching, temperature and shading histories.

    PubMed

    Fabricius, K E; Mieog, J C; Colin, P L; Idip, D; van Oppen, M J H

    2004-08-01

    The potential of corals to associate with more temperature-tolerant strains of algae (zooxanthellae, Symbiodinium) can have important implications for the future of coral reefs in an era of global climate change. In this study, the genetic identity and diversity of zooxanthellae was investigated at three reefs with contrasting histories of bleaching mortality, water temperature and shading, in the Republic of Palau (Micronesia). Single-stranded conformation polymorphism and sequence analysis of the ribosomal DNA internal transcribed spacer (ITS)1 region was used for genotyping. A chronically warm but partly shaded coral reef in a marine lake that is hydrographically well connected to the surrounding waters harboured only two single-stranded conformation polymorphism profiles (i.e. zooxanthella communities). It consisted only of Symbiodinium D in all 13 nonporitid species and two Porites species investigated, with the remaining five Porites harbouring C*. Despite the high temperature in this lake (> 0.5 degrees above ambient), this reef did not suffer coral mortality during the (1998) bleaching event, however, no bleaching-sensitive coral families and genera occur in the coral community. This setting contrasts strongly with two other reefs with generally lower temperatures, in which 10 and 12 zooxanthella communities with moderate to low proportions of clade D zooxanthellae were found. The data indicate that whole coral assemblages, when growing in elevated seawater temperatures and at reduced irradiance, can be composed of colonies associated with the more thermo-tolerant clade D zooxanthellae. Future increases in seawater temperature might, therefore, result in an increasing prevalence of Symbiodinium phylotype D in scleractinian corals, possibly associated with a loss of diversity in both zooxanthellae and corals.

  3. Gradients in coral reef communities exposed to muddy river discharge in Pohnpei, Micronesia

    NASA Astrophysics Data System (ADS)

    Golbuu, Yimnang; Fabricius, Katharina; Victor, Steven; Richmond, Robert H.

    2008-01-01

    This study analyzed how coral communities change along a gradient of increasing exposure to a mud-discharging river in the Enipein Catchment, Pohnpei, Micronesia. Using video transects, we quantified benthic communities at five sites along a gradient moving away from the river mouth towards the barrier reef. The most river-impacted site was characterized by a high accumulation of mud, low coral cover and low coral diversity. Although coral cover leveled off at ˜400 m from the river mouth to values found at the outer-most sites, coral diversity continued to increase with increasing distance, suggesting that the most distant site was still impacted by the river discharges. Fungiidae, Pavona, Acropora, Pachyseris and Porites rus all significantly increased in cover with distance from the river, while Turbinaria decreased. The combined presence and abundance of these six species groups, together with coral species richness, may help to indicate the effects of terrestrial runoff in similar runoff-exposed settings around Micronesia, whereas coral cover is not a sensitive indicator for river impact. Coral reefs are important resources for the people of Pohnpei. To prevent further degradation of this important resource, an integrated watershed approach is needed to control terrestrial activities.

  4. Spatial and Species Variations in Bacterial Communities Associated with Corals from the Red Sea as Revealed by Pyrosequencing

    PubMed Central

    Lee, On On; Yang, Jiangke; Bougouffa, Salim; Wang, Yong; Batang, Zenon; Tian, Renmao; Al-Suwailem, Abdulaziz

    2012-01-01

    Microbial associations with corals are common and are most likely symbiotic, although their diversity and relationships with environmental factors and host species remain unclear. In this study, we adopted a 16S rRNA gene tag-pyrosequencing technique to investigate the bacterial communities associated with three stony Scleractinea and two soft Octocorallia corals from three locations in the Red Sea. Our results revealed highly diverse bacterial communities in the Red Sea corals, with more than 600 ribotypes detected and up to 1,000 species estimated from a single coral species. Altogether, 21 bacterial phyla were recovered from the corals, of which Gammaproteobacteria was the most dominant group, and Chloroflexi, Chlamydiae, and the candidate phylum WS3 were reported in corals for the first time. The associated bacterial communities varied greatly with location, where environmental conditions differed significantly. Corals from disturbed areas appeared to share more similar bacterial communities, but larger variations in community structures were observed between different coral species from pristine waters. Ordination methods identified salinity and depth as the most influential parameters affecting the abundance of Vibrio, Pseudoalteromonas, Serratia, Stenotrophomonas, Pseudomonas, and Achromobacter in the corals. On the other hand, bacteria such as Chloracidobacterium and Endozoicomonas were more sensitive to the coral species, suggesting that the host species type may be influential in the associated bacterial community, as well. The combined influences of the coral host and environmental factors on the associated microbial communities are discussed. This study represents the first comparative study using tag-pyrosequencing technology to investigate the bacterial communities in Red Sea corals. PMID:22865078

  5. Shifts in bacterial communities of two caribbean reef-building coral species affected by white plague disease

    PubMed Central

    Cárdenas, Anny; Rodriguez-R, Luis M; Pizarro, Valeria; Cadavid, Luis F; Arévalo-Ferro, Catalina

    2012-01-01

    Coral reefs are deteriorating at an alarming rate mainly as a consequence of the emergence of coral diseases. The white plague disease (WPD) is the most prevalent coral disease in the southwestern Caribbean, affecting dozens of coral species. However, the identification of a single causal agent has proved problematic. This suggests more complex etiological scenarios involving alterations in the dynamic interaction between environmental factors, the coral immune system and the symbiotic microbial communities. Here we compare the microbiome of healthy and WPD-affected corals from the two reef-building species Diploria strigosa and Siderastrea siderea collected at the Tayrona National Park in the Caribbean of Colombia. Microbiomes were analyzed by combining culture-dependent methods and pyrosequencing of 16S ribosomal DNA (rDNA) V5-V6 hypervariable regions. A total of 20 410 classifiable 16S rDNA sequences reads were obtained including all samples. No significant differences in operational taxonomic unit diversity were found between healthy and affected tissues; however, a significant increase of Alphaproteobacteria and a concomitant decrease in the Beta- and Gammaproteobacteria was observed in WPD-affected corals of both species. Significant shifts were also observed in the orders Rhizobiales, Caulobacteriales, Burkholderiales, Rhodobacterales, Aleteromonadales and Xanthomonadales, although they were not consistent between the two coral species. These shifts in the microbiome structure of WPD-affected corals suggest a loss of community-mediated growth control mechanisms on bacterial populations specific for each holobiont system. PMID:21955993

  6. Host shift and speciation in a coral-feeding nudibranch

    PubMed Central

    Faucci, Anuschka; Toonen, Robert J; Hadfield, Michael G

    2006-01-01

    While the role of host preference in ecological speciation has been investigated extensively in terrestrial systems, very little is known in marine environments. Host preference combined with mate choice on the preferred host can lead to population subdivision and adaptation leading to host shifts. We use a phylogenetic approach based on two mitochondrial genetic markers to disentangle the taxonomic status and to investigate the role of host specificity in the speciation of the nudibranch genus Phestilla (Gastropoda, Opisthobranchia) from Guam, Palau and Hawaii. Species of the genus Phestilla complete their life cycle almost entirely on their specific host coral (species of Porites, Goniopora and Tubastrea). They reproduce on their host coral and their planktonic larvae require a host-specific chemical cue to metamorphose and settle onto their host. The phylogenetic trees of the combined cytochrome oxidase I and ribosomal 16S gene sequences clarify the relationship among species of Phestilla identifying most of the nominal species as monophyletic clades. We found a possible case of host shift from Porites to Goniopora and Tubastrea in sympatric Phestilla spp. This represents one of the first documented cases of host shift as a mechanism underlying speciation in a marine invertebrate. Furthermore, we found highly divergent clades within Phestilla sp. 1 and Phestilla minor (8.1–11.1%), suggesting cryptic speciation. The presence of a strong phylogenetic signal for the coral host confirms that the tight link between species of Phestilla and their host coral probably played an important role in speciation within this genus. PMID:17134995

  7. Stable and sporadic symbiotic communities of coral and algal holobionts

    PubMed Central

    Hester, Eric R; Barott, Katie L; Nulton, Jim; Vermeij, Mark JA; Rohwer, Forest L

    2016-01-01

    Coral and algal holobionts are assemblages of macroorganisms and microorganisms, including viruses, Bacteria, Archaea, protists and fungi. Despite a decade of research, it remains unclear whether these associations are spatial–temporally stable or species-specific. We hypothesized that conflicting interpretations of the data arise from high noise associated with sporadic microbial symbionts overwhelming signatures of stable holobiont members. To test this hypothesis, the bacterial communities associated with three coral species (Acropora rosaria, Acropora hyacinthus and Porites lutea) and two algal guilds (crustose coralline algae and turf algae) from 131 samples were analyzed using a novel statistical approach termed the Abundance-Ubiquity (AU) test. The AU test determines whether a given bacterial species would be present given additional sampling effort (that is, stable) versus those species that are sporadically associated with a sample. Using the AU test, we show that coral and algal holobionts have a high-diversity group of stable symbionts. Stable symbionts are not exclusive to one species of coral or algae. No single bacterial species was ubiquitously associated with one host, showing that there is not strict heredity of the microbiome. In addition to the stable symbionts, there was a low-diversity community of sporadic symbionts whose abundance varied widely across individual holobionts of the same species. Identification of these two symbiont communities supports the holobiont model and calls into question the hologenome theory of evolution. PMID:26555246

  8. Long-term impacts of coral bleaching events on the world's warmest reefs.

    PubMed

    Burt, John; Al-Harthi, Suaad; Al-Cibahy, Ashraf

    2011-10-01

    The southern Arabian Gulf houses some of the most thermally tolerant corals on earth, but severe bleaching in the late 1990s caused widespread mortality. More than a decade later, corals still dominated benthos (mean: 40 ± 3% cover on 10 sites spanning > 350 km; range: 11.0-65.6%), but coral communities varied spatially. Sites to the west generally had low species richness and coral cover (mean: 3.2 species per transect, 31% cover), with Porites dominated communities (88% of coral) that are distinct from more diverse and higher cover eastern sites (mean: 10.3 species per transect, 62% cover). These patterns reflect both the more extreme bleaching to the west in the late 1990s as well as the higher faviid dominated recruitment to the east in subsequent years. There has been limited recovery of the formerly dominant Acropora, which now represents <1% of the benthos, likely as a result of recruitment failure. Results indicate that severe bleaching can have substantial long-term impacts on coral communities, even in areas with corals tolerant to environmental extremes.

  9. Coral disease dynamics at a subtropical location, Solitary Islands Marine Park, eastern Australia

    NASA Astrophysics Data System (ADS)

    Dalton, Steven J.; Smith, Stephen D. A.

    2006-03-01

    Recent observations suggest that a spreading disease is increasingly contributing to hard coral mortality in the Solitary Islands Marine Park, NSW, Australia. This study determined coral disease prevalence and rate-of-spread through individual affected colonies and investigated the effect this epizootic had on coral populations at sites adjacent to South West Solitary Island. Quantitative data were collected between 2002 and 2004 using photographic and video methods, and visual census along radial arc belt transects. Disease similar to the reported white syndrome and white plague was apparent, spreading through hard coral species from the genera Turbinaria, Acropora, Goniastrea, Pocillopora, Stylophora and Porites. Coral disease prevalence varied between survey dates with mean prevalence increasing from 8.55% during March 2003 to 13.58% in June and declining to 7.75% in September and 6.21% during March 2004. There was a significant difference in mean prevalence between the affected species (p<0.001) and an overall difference between survey dates (p=0.001). Additionally, the rate-of-spread of coral disease through coral colonies determined using repeated, seasonal, still photographs followed similar patterns, with disease progression differing between affected species (p=0.004), and between survey dates (p<0.001). Analysis of the video-transects indicated significant difference in disease prevalence over larger spatial scales (100s of m). However, disease frequency did not vary significantly between 2002 and 2003.

  10. Coral population dynamics across consecutive mass mortality events.

    PubMed

    Riegl, Bernhard; Purkis, Sam

    2015-11-01

    Annual coral mortality events due to increased atmospheric heat may occur regularly from the middle of the century and are considered apocalyptic for coral reefs. In the Arabian/Persian Gulf, this situation has already occurred and population dynamics of four widespread corals (Acropora downingi, Porites harrisoni, Dipsastrea pallida, Cyphastrea micropthalma) were examined across the first-ever occurrence of four back-to-back mass mortality events (2009-2012). Mortality was driven by diseases in 2009, bleaching and subsequent diseases in 2010/2011/2012. 2009 reduced P. harrisoni cover and size, the other events increasingly reduced overall cover (2009: -10%; 2010: -20%; 2011: -20%; 2012: -15%) and affected all examined species. Regeneration was only observed after the first disturbance. P. harrisoni and A. downingi severely declined from 2010 due to bleaching and subsequent white syndromes, while D. pallida and P. daedalea declined from 2011 due to bleaching and black-band disease. C. microphthalma cover was not affected. In all species, most large corals were lost while fission due to partial tissue mortality bolstered small size classes. This general shrinkage led to a decrease of coral cover and a dramatic reduction of fecundity. Transition matrices for disturbed and undisturbed conditions were evaluated as Life Table Response Experiment and showed that C. microphthalma changed the least in size-class dynamics and fecundity, suggesting they were 'winners'. In an ordered 'degradation cascade', impacts decreased from the most common to the least common species, leading to step-wise removal of previously dominant species. A potentially permanent shift from high- to low-coral cover with different coral community and size structure can be expected due to the demographic dynamics resultant from the disturbances. Similarities to degradation of other Caribbean and Pacific reefs are discussed. As comparable environmental conditions and mortality patterns must be

  11. Coral Reefs at the Northernmost Tip of Borneo: An Assessment of Scleractinian Species Richness Patterns and Benthic Reef Assemblages

    PubMed Central

    Waheed, Zarinah; van Mil, Harald G. J.; Syed Hussein, Muhammad Ali; Jumin, Robecca; Golam Ahad, Bobita; Hoeksema, Bert W.

    2015-01-01

    The coral reefs at the northernmost tip of Sabah, Borneo will be established under a marine protected area: the Tun Mustapha Park (TMP) by the end of 2015. This area is a passage where the Sulu Sea meets the South China Sea and it is situated at the border of the area of maximum marine biodiversity, the Coral Triangle. The TMP includes fringing and patch reefs established on a relatively shallow sea floor. Surveys were carried out to examine features of the coral reefs in terms of scleractinian species richness, and benthic reef assemblages following the Reef Check substrate categories, with emphasis on hard coral cover. Variation in scleractinian diversity was based on the species composition of coral families Fungiidae (n = 39), Agariciidae (n = 30) and Euphylliidae (n = 15). The number of coral species was highest at reefs with a larger depth gradient i.e. at the periphery of the study area and in the deep South Banggi Channel. Average live hard coral cover across the sites was 49%. Only 7% of the examined reefs had > 75% hard coral cover, while the majority of the reef sites were rated fair (51%) and good (38%). Sites with low coral cover and high rubble fragments are evidence of blast fishing, although the observed damage appeared old. Depth was a dominant factor in influencing the coral species composition and benthic reef communities in the TMP. Besides filling in the information gaps regarding species richness and benthic cover for reef areas that were previously without any data, the results of this study together with information that is already available on the coral reefs of TMP will be used to make informed decisions on zoning plans for conservation priorities in the proposed park. PMID:26719987

  12. Coral Reefs at the Northernmost Tip of Borneo: An Assessment of Scleractinian Species Richness Patterns and Benthic Reef Assemblages.

    PubMed

    Waheed, Zarinah; van Mil, Harald G J; Syed Hussein, Muhammad Ali; Jumin, Robecca; Golam Ahad, Bobita; Hoeksema, Bert W

    2015-01-01

    The coral reefs at the northernmost tip of Sabah, Borneo will be established under a marine protected area: the Tun Mustapha Park (TMP) by the end of 2015. This area is a passage where the Sulu Sea meets the South China Sea and it is situated at the border of the area of maximum marine biodiversity, the Coral Triangle. The TMP includes fringing and patch reefs established on a relatively shallow sea floor. Surveys were carried out to examine features of the coral reefs in terms of scleractinian species richness, and benthic reef assemblages following the Reef Check substrate categories, with emphasis on hard coral cover. Variation in scleractinian diversity was based on the species composition of coral families Fungiidae (n = 39), Agariciidae (n = 30) and Euphylliidae (n = 15). The number of coral species was highest at reefs with a larger depth gradient i.e. at the periphery of the study area and in the deep South Banggi Channel. Average live hard coral cover across the sites was 49%. Only 7% of the examined reefs had > 75% hard coral cover, while the majority of the reef sites were rated fair (51%) and good (38%). Sites with low coral cover and high rubble fragments are evidence of blast fishing, although the observed damage appeared old. Depth was a dominant factor in influencing the coral species composition and benthic reef communities in the TMP. Besides filling in the information gaps regarding species richness and benthic cover for reef areas that were previously without any data, the results of this study together with information that is already available on the coral reefs of TMP will be used to make informed decisions on zoning plans for conservation priorities in the proposed park.

  13. Modeling vertical coral connectivity and mesophotic refugia

    NASA Astrophysics Data System (ADS)

    Holstein, Daniel M.; Paris, Claire B.; Vaz, Ana C.; Smith, Tyler B.

    2016-03-01

    Whether mesophotic reefs will behave as refugia for corals threatened by global climate change and coastal development depends on vertical exchange of larvae between diverse habitats. Here we use a biophysical model of larval dispersal to estimate vertical connectivity of a broadcasting ( Orbicella faveolata) and a brooding ( Porites astreoides) species of coral in the US Virgin Islands. Modeling predicts subsidy to shallow areas by mesophotic larvae of both species based on local hydrology, adult reproductive characteristics, larval traits, and a wide range of scenarios developed to test depth-sensitive factors, such as fertilization rates and post-settlement survivorship. In extreme model scenarios of reduced fertilization and post-settlement survivorship of mesophotic larvae, 1-10 % local mesophotic subsidy to shallow recruitment is predicted for both species, which are demographically significant. Although direct vertical connectivity is higher for the broadcaster, the brooder demonstrates higher local multigenerational vertical connectivity, which suggests that local P. astreoides populations are more resilient than those of O. faveolata, and corroborates field studies. As shallow habitat degrades, mesophotic-shallow subsidy is predicted to increase for both species. This study is the first of its kind to simulate larval dispersal and settlement between habitats of different depths, and these findings have local, regional, and global implications for predicting and managing coral reef persistence in a changing climate.

  14. Coral-Associated Bacterial Diversity Is Conserved across Two Deep-Sea Anthothela Species

    PubMed Central

    Lawler, Stephanie N.; Kellogg, Christina A.; France, Scott C.; Clostio, Rachel W.; Brooke, Sandra D.; Ross, Steve W.

    2016-01-01

    Cold-water corals, similar to tropical corals, contain diverse and complex microbial assemblages. These bacteria provide essential biological functions within coral holobionts, facilitating increased nutrient utilization and production of antimicrobial compounds. To date, few cold-water octocoral species have been analyzed to explore the diversity and abundance of their microbial associates. For this study, 23 samples of the family Anthothelidae were collected from Norfolk (n = 12) and Baltimore Canyons (n = 11) from the western Atlantic in August 2012 and May 2013. Genetic testing found that these samples comprised two Anthothela species (Anthothela grandiflora and Anthothela sp.) and Alcyonium grandiflorum. DNA was extracted and sequenced with primers targeting the V4–V5 variable region of the 16S rRNA gene using 454 pyrosequencing with GS FLX Titanium chemistry. Results demonstrated that the coral host was the primary driver of bacterial community composition. Al. grandiflorum, dominated by Alteromonadales and Pirellulales had much higher species richness, and a distinct bacterial community compared to Anthothela samples. Anthothela species (A. grandiflora and Anthothela sp.) had very similar bacterial communities, dominated by Oceanospirillales and Spirochaetes. Additional analysis of core-conserved bacteria at 90% sample coverage revealed genus level conservation across Anthothela samples. This core included unclassified Oceanospirillales, Kiloniellales, Campylobacterales, and genus Spirochaeta. Members of this core were previously recognized for their functional capabilities in nitrogen cycling and suggest the possibility of a nearly complete nitrogen cycle within Anthothela species. Overall, many of the bacterial associates identified in this study have the potential to contribute to the acquisition and cycling of nutrients within the coral holobiont. PMID:27092120

  15. Coral-associated bacterial diversity is conserved across two deep-sea Anthothela species

    USGS Publications Warehouse

    Lawler, Stephanie N.; Kellogg, Christina A.; France, Scott C; Clostio, Rachel W; Brooke, Sandra D.; Ross, Steve W.

    2016-01-01

    Cold-water corals, similar to tropical corals, contain diverse and complex microbial assemblages. These bacteria provide essential biological functions within coral holobionts, facilitating increased nutrient utilization and production of antimicrobial compounds. To date, few cold-water octocoral species have been analyzed to explore the diversity and abundance of their microbial associates. For this study, 23 samples of the family Anthothelidae were collected from Norfolk (n = 12) and Baltimore Canyons (n = 11) from the western Atlantic in August 2012 and May 2013. Genetic testing found that these samples comprised two Anthothela species (Anthothela grandiflora and Anthothela sp.) and Alcyonium grandiflorum. DNA was extracted and sequenced with primers targeting the V4-V5 variable region of the 16S rRNA gene using 454 pyrosequencing with GS FLX Titanium chemistry. Results demonstrated that the coral host was the primary driver of bacterial community composition. Al. grandiflorum, dominated by Alteromonadales and Pirellulales had much higher species richness, and a distinct bacterial community compared to Anthothela samples. Anthothela species (A. grandiflora and Anthothela sp.) had very similar bacterial communities, dominated by Oceanospirillales and Spirochaetes. Additional analysis of core-conserved bacteria at 90% sample coverage revealed genus level conservation across Anthothela samples. This core included unclassified Oceanospirillales, Kiloniellales, Campylobacterales, and genus Spirochaeta. Members of this core were previously recognized for their functional capabilities in nitrogen cycling and suggest the possibility of a nearly complete nitrogen cycle within Anthothela species. Overall, many of the bacterial associates identified in this study have the potential to contribute to the acquisition and cycling of nutrients within the coral holobiont.

  16. Coral-Associated Bacterial Diversity Is Conserved across Two Deep-Sea Anthothela Species.

    PubMed

    Lawler, Stephanie N; Kellogg, Christina A; France, Scott C; Clostio, Rachel W; Brooke, Sandra D; Ross, Steve W

    2016-01-01

    Cold-water corals, similar to tropical corals, contain diverse and complex microbial assemblages. These bacteria provide essential biological functions within coral holobionts, facilitating increased nutrient utilization and production of antimicrobial compounds. To date, few cold-water octocoral species have been analyzed to explore the diversity and abundance of their microbial associates. For this study, 23 samples of the family Anthothelidae were collected from Norfolk (n = 12) and Baltimore Canyons (n = 11) from the western Atlantic in August 2012 and May 2013. Genetic testing found that these samples comprised two Anthothela species (Anthothela grandiflora and Anthothela sp.) and Alcyonium grandiflorum. DNA was extracted and sequenced with primers targeting the V4-V5 variable region of the 16S rRNA gene using 454 pyrosequencing with GS FLX Titanium chemistry. Results demonstrated that the coral host was the primary driver of bacterial community composition. Al. grandiflorum, dominated by Alteromonadales and Pirellulales had much higher species richness, and a distinct bacterial community compared to Anthothela samples. Anthothela species (A. grandiflora and Anthothela sp.) had very similar bacterial communities, dominated by Oceanospirillales and Spirochaetes. Additional analysis of core-conserved bacteria at 90% sample coverage revealed genus level conservation across Anthothela samples. This core included unclassified Oceanospirillales, Kiloniellales, Campylobacterales, and genus Spirochaeta. Members of this core were previously recognized for their functional capabilities in nitrogen cycling and suggest the possibility of a nearly complete nitrogen cycle within Anthothela species. Overall, many of the bacterial associates identified in this study have the potential to contribute to the acquisition and cycling of nutrients within the coral holobiont.

  17. Ten years after the crime: Lasting effects of damage from a cruise ship anchor on a coral reef in St. John, U.S. Virgin Islands

    USGS Publications Warehouse

    Rogers, C.S.; Garrison, V.H.

    2001-01-01

    In October 1988, a cruise ship dropped its anchor on a coral reef in Virgin Islands National Park, St. John, creating a distinct scar roughly 128 m long and 3 m wide from a depth of 22 m to a depth of 6 m. The anchor pulverized coral colonies and smashed part of the reef framework. In April 1991, nine permanent quadrats (1 m2) were established inside the scar over a depth range of 9 m to 12.5 m. At that time, average coral cover inside the scar was less than 1%. These quadrats were surveyed again in 1992, 1993, 1994, 1995 and 1998. Recruits of 19 coral species have been observed, with Agaricia agaricites and Porites spp. the most abundant. Quadrats surveyed outside the scar in June 1994 over the same depth range had a higher percent coral cover (mean = 7.4%, SD = 4.5) and greater average size (maximum length) of coral colonies than in quadrats inside the damaged area. Although coral recruits settle into the scar in high densities, live coral cover has not increased significantly in the last 10 yrs, reflecting poor survival and growth of newly settled corals. The relatively planar aspect of the scar may increase the vulnerability of the recruits to abrasion and mortality from shifting sediments. Ten years after the anchor damage occurred, live coral cover in the still-visible scar (mean = 2.6%, SD = 2.7) remains well below the cover found in the adjacent, undamaged reef.

  18. EFFECTS OF ENVIRONMENTAL PARAMETERS ON THE GROWTH CHARACTERISTICS OF SYMBIODINIUM SPP. ISOLATED FROM CORALS

    EPA Science Inventory

    Symbiodinium spp. were isolated from Porites porites (JR02F2 and RD03), Montipora capitata (JR12A7), Madracis mirabolis (RD02), Montastrea faveolata (RD04), Pocillopora damicornis (JR13E1), and an unknown coral (RD01). Growth rates and the distribution between motile gymnodinoid ...

  19. Reef-coral refugia in a rapidly changing ocean.

    PubMed

    Cacciapaglia, Chris; van Woesik, Robert

    2015-06-01

    This study sought to identify climate-change thermal-stress refugia for reef corals in the Indian and Pacific Oceans. A species distribution modeling approach was used to identify refugia for 12 coral species that differed considerably in their local response to thermal stress. We hypothesized that the local response of coral species to thermal stress might be similarly reflected as a regional response to climate change. We assessed the contemporary geographic range of each species and determined their temperature and irradiance preferences using a k-fold algorithm to randomly select training and evaluation sites. That information was applied to downscaled outputs of global climate models to predict where each species is likely to exist by the year 2100. Our model was run with and without a 1°C capacity to adapt to the rising ocean temperature. The results show a positive exponential relationship between the current area of habitat that coral species occupy and the predicted area of habitat that they will occupy by 2100. There was considerable decoupling between scales of response, however, and with further ocean warming some 'winners' at local scales will likely become 'losers' at regional scales. We predicted that nine of the 12 species examined will lose 24-50% of their current habitat. Most reductions are predicted to occur between the latitudes 5-15°, in both hemispheres. Yet when we modeled a 1°C capacity to adapt, two ubiquitous species, Acropora hyacinthus and Acropora digitifera, were predicted to retain much of their current habitat. By contrast, the thermally tolerant Porites lobata is expected to increase its current distribution by 14%, particularly southward along the east and west coasts of Australia. Five areas were identified as Indian Ocean refugia, and seven areas were identified as Pacific Ocean refugia for reef corals under climate change. All 12 of these reef-coral refugia deserve high-conservation status.

  20. Spatial variation in background mortality among dominant coral taxa on Australia's Great Barrier Reef.

    PubMed

    Pisapia, Chiara; Pratchett, Morgan S

    2014-01-01

    Even in the absence of major disturbances (e.g., cyclones, bleaching), corals are consistently subject to high levels of background mortality, which undermines individual fitness and resilience of coral colonies. Partial mortality may impact coral response to climate change by reducing colony ability to recover between major acute stressors. This study quantified proportion of injured versus uninjured colonies (the prevalence of injuries) and instantaneous measures of areal extent of injuries across individual colonies (the severity of injuries), in four common coral species along the Great Barrier Reef in Australia: massive Porites, encrusting Montipora, Acropora hyacinthus and Pocillopora damicornis. A total of 2,276 adult colonies were surveyed three latitudinal sectors, nine reefs and 27 sites along 1000 km2 on the Great Barrier Reef. The prevalence of injuries was very high, especially for Porites spp (91%) and Montipora encrusting (85%) and varied significantly, but most lay at small spatial scales (e.g., among colonies positioned <10-m apart). Similarly, severity of background partial mortality was surprisingly high (between 5% and 21%) but varied greatly among colonies within the same site and habitat. This study suggests that intraspecific variation in partial mortality between adjacent colonies may be more important than variation between colonies in different latitudinal sectors or reefs. Differences in the prevalence and severity of background partial mortality have significant ramifications for coral capacity to cope with increasing acute disturbances, such as climate-induced coral bleaching. These data are important for understanding coral responses to increasing stressors, and in particular for predicting their capacity to recover between subsequent disturbances.

  1. Coral Pigments: Quantification Using HPLC and Detection by Remote Sensing

    NASA Technical Reports Server (NTRS)

    Cottone, Mary C.

    1995-01-01

    Widespread coral bleaching (loss of pigments of symbiotic dinoflagellates), and the corresponding decline in coral reef health worldwide, mandates the monitoring of coral pigmentation. Samples of the corals Porites compressa and P. lobata were collected from a healthy reef at Puako, Hawaii, and chlorophyll (chl) a, peridinin, and Beta-carotene (Beta-car) were quantified using reverse-phase high performance liquid chromatography (HPLC). Detailed procedures are presented for the extraction of the coral pigments in 90% acetone, and the separation, identification, and quantification of the major zooxanthellar pigments using spectrophotometry and a modification of the HPLC system described by Mantoura and Llewellyn (1983). Beta-apo-8-carotenal was found to be inadequate as in internal standard, due to coelution with chl b and/or chl a allomer in the sample extracts. Improvements are suggested, which may result in better resolution of the major pigments and greater accuracy in quantification. Average concentrations of peridinin, chl a, and Beta-car in corals on the reef were 5.01, 8.59, and 0.29, micro-grams/cm(exp 2), respectively. Average concentrations of peridinin and Beta-car did not differ significantly between the two coral species sampled; however, the mean chl a concentration in P. compressa specimens (7.81 ,micro-grams/cm(exp 2) was significantly lower than that in P. lobata specimens (9.96 11g/cm2). Chl a concentrations determined spectrophotometrically were significantly higher than those generated through HPLC, suggesting that spectrophotometry overestimates chl a concentrations. The average ratio of chl a-to-peridinin concentrations was 1.90, with a large (53%) coefficient of variation and a significant difference between the two species sampled. Additional data are needed before conclusions can be drawn regarding average pigment concentrations in healthy corals and the consistency of the chl a/peridinin ratio. The HPLC pigment concentration values

  2. Asymmetric competition prevents the outbreak of an opportunistic species after coral reef degradation.

    PubMed

    González-Rivero, Manuel; Bozec, Yves-Marie; Chollett, Iliana; Ferrari, Renata; Schönberg, Christine H L; Mumby, Peter J

    2016-05-01

    Disturbance releases space and allows the growth of opportunistic species, excluded by the old stands, with a potential to alter community dynamics. In coral reefs, abundances of fast-growing, and disturbance-tolerant sponges are expected to increase and dominate as space becomes available following acute coral mortality events. Yet, an increase in abundance of these opportunistic species has been reported in only a few studies, suggesting certain mechanisms may be acting to regulate sponge populations. To gain insights into mechanisms of population control, we simulated the dynamics of the common reef-excavating sponge Cliona tenuis in the Caribbean using an individual-based model. An orthogonal hypothesis testing approach was used, where four candidate mechanisms-algal competition, stock-recruitment limitation, whole and partial mortality-were incorporated sequentially into the model and the results were tested against independent field observations taken over a decade in Belize, Central America. We found that releasing space after coral mortality can promote C. tenuis outbreaks, but such outbreaks can be curtailed by macroalgal competition. The asymmetrical competitive superiority of macroalgae, given by their capacity to pre-empt space and outcompete with the sponge in a size-dependant fashion, supports their capacity to steal the opportunity from other opportunists. While multiple system stages can be expected in coral reefs following intense perturbation macroalgae may prevent the growth of other space-occupiers, such as bioeroding sponges, under low grazing pressure.

  3. Predators reduce abundance and species richness of coral reef fish recruits via non-selective predation

    NASA Astrophysics Data System (ADS)

    Heinlein, J. M.; Stier, A. C.; Steele, M. A.

    2010-06-01

    Predators have important effects on coral reef fish populations, but their effects on community structure have only recently been investigated and are not yet well understood. Here, the effect of predation on the diversity and abundance of young coral reef fishes was experimentally examined in Moorea, French Polynesia. Effects of predators were quantified by monitoring recruitment of fishes onto standardized patch reefs in predator-exclosure cages or uncaged reefs. At the end of the 54-day experiment, recruits were 74% less abundant on reefs exposed to predators than on caged ones, and species richness was 42% lower on reefs exposed to predators. Effects of predators varied somewhat among families, however, rarefaction analysis indicated that predators foraged non-selectively among species. These results indicate that predation can alter diversity of reef fish communities by indiscriminately reducing the abundance of fishes soon after settlement, thereby reducing the number of species present on reefs.

  4. Spatial predictability of juvenile fish species richness and abundance in a coral reef environment

    NASA Astrophysics Data System (ADS)

    Mellin, C.; Andréfouët, S.; Ponton, D.

    2007-12-01

    Juvenile reef fish communities represent an essential component of coral reef ecosystems in the current focus of fish population dynamics and coral reef resilience. Juvenile fish survival depends on habitat characteristics and is, following settlement, the first determinant of the number of individuals within adult populations. The goal of this study was to provide methods for mapping juvenile fish species richness and abundance into spatial domains suitable for micro and meso-scale analysis and management decisions. Generalized Linear Models predicting juvenile fish species richness and abundance were developed according to spatial and temporal environmental variables measured from 10 m up to 10 km in the southwest lagoon of New Caledonia. The statistical model was further spatially generalized using a 1.5-m resolution, independently created, remotely sensed, habitat map. This procedure revealed that : (1) spatial factors at 10 to 100-m scale explained up to 71% of variability in juvenile species richness, (2) a small improvement (75%) was gained when a combination of environmental variables at different spatial and temporal scales was used and (3) the coupling of remotely sensed data, geographical information system tools and point-based ecological data showed that the highest species richness and abundance were predicted along a narrow margin overlapping the coral reef flat and adjacent seagrass beds. Spatially explicit models of species distribution may be relevant for the management of reef communities when strong relationships exist between faunistic and environmental variables and when models are built at appropriate scales.

  5. Cyphastreakausti sp. n. (Cnidaria, Anthozoa, Scleractinia), a new species of reef coral from the Red Sea.

    PubMed

    Bouwmeester, Jessica; Benzoni, Francesca; Baird, Andrew H; Berumen, Michael L

    2015-01-01

    A new scleractinian coral species, Cyphastreakausti sp. n., is described from 13 specimens from the Red Sea. It is characterised by the presence of eight primary septa, unlike the other species of the genus, which have six, ten or 12 primary septa. The new species has morphological affinities with Cyphastreamicrophthalma, from which it can be distinguished by the lower number of septa (on average eight instead of ten), and smaller calices and corallites. This species was observed in the northern and central Red Sea and appears to be absent from the southern Red Sea.

  6. Incorporating climate and ocean change into extinction risk assessments for 82 coral species.

    PubMed

    Brainard, Russell E; Weijerman, Mariska; Eakin, C Mark; McElhany, Paul; Miller, Margaret W; Patterson, Matt; Piniak, Gregory A; Dunlap, Matthew J; Birkeland, Charles

    2013-12-01

    Many marine invertebrate species facing potential extinction have uncertain taxonomies and poorly known demographic and ecological traits. Uncertainties are compounded when potential extinction drivers are climate and ocean changes whose effects on even widespread and abundant species are only partially understood. The U.S. Endangered Species Act mandates conservation management decisions founded on the extinction risk to species based on the best available science at the time of consideration-requiring prompt action rather than awaiting better information. We developed an expert-opinion threat-based approach that entails a structured voting system to assess extinction risk from climate and ocean changes and other threats to 82 coral species for which population status and threat response information was limited. Such methods are urgently needed because constrained budgets and manpower will continue to hinder the availability of desired data for many potentially vulnerable marine species. Significant species-specific information gaps and uncertainties precluded quantitative assessments of habitat loss or population declines and necessitated increased reliance on demographic characteristics and threat vulnerabilities at genus or family levels. Adapting some methods (e.g., a structured voting system) used during other assessments and developing some new approaches (e.g., integrated assessment of threats and demographic characteristics), we rated the importance of threats contributing to coral extinction risk and assessed those threats against population status and trend information to evaluate each species' extinction risk over the 21st century. This qualitative assessment resulted in a ranking with an uncertainty range for each species according to their estimated likelihood of extinction. We offer guidance on approaches for future biological extinction risk assessments, especially in cases of data-limited species likely to be affected by global-scale threats

  7. Population biology of coral trout species in eastern Torres Strait: Implications for fishery management

    NASA Astrophysics Data System (ADS)

    Williams, Ashley J.; Currey, Leanne M.; Begg, Gavin A.; Murchie, Cameron D.; Ballagh, Aaron C.

    2008-09-01

    Coral trout ( Plectropomus spp.) are the main target species for commercial fishers in the eastern Torres Strait Reef Line Fishery (ETS RLF). The four species of coral trout known to occur in Torres Strait: Plectropomus leopardus, Plectropomus maculatus, Plectropomus areolatus and Plectropomus laevis are currently managed as a single species in Torres Strait, as there is no species-specific biological information available for the region which could be used to assess whether species differ in their response to fishing pressure. The aim of our study was to determine whether it is appropriate (biologically) to manage coral trout in the ETS RLF as a single species group or whether different management arrangements are required for some species. We used catch data and biological data from samples collected by commercial fishers to examine the distribution within Torres Strait and estimate a range of biological parameters for P. leopardus, P. maculatus and P. areolatus. Insufficient P. laevis samples were collected to reliably examine this species. Results indicated that the population biology, particularly the reproductive biology, of P. areolatus was substantially different to both P. leopardus and P. maculatus. Although it is difficult to predict the response to fishing, P. areolatus may be more vulnerable to fishing than P. leopardus and P. maculatus, due to the larger size at sex change observed for this species and the very low proportion of males protected by the current minimum size limit. Therefore, while the common management arrangements for P. leopardus and P. maculatus appear to be adequate for these species, separate management arrangements are needed for the sustainable harvest of P. areolatus populations in the ETS. Specifically, we recommend the introduction of a maximum size limit for P. areolatus, in addition to the current minimum size limit, which may allow a proportion of males some protection from fishing.

  8. Species-specific control of external superoxide levels by the coral holobiont during a natural bleaching event

    NASA Astrophysics Data System (ADS)

    Diaz, Julia M.; Hansel, Colleen M.; Apprill, Amy; Brighi, Caterina; Zhang, Tong; Weber, Laura; McNally, Sean; Xun, Liping

    2016-12-01

    The reactive oxygen species superoxide (O2.-) is both beneficial and detrimental to life. Within corals, superoxide may contribute to pathogen resistance but also bleaching, the loss of essential algal symbionts. Yet, the role of superoxide in coral health and physiology is not completely understood owing to a lack of direct in situ observations. By conducting field measurements of superoxide produced by corals during a bleaching event, we show substantial species-specific variation in external superoxide levels, which reflect the balance of production and degradation processes. Extracellular superoxide concentrations are independent of light, algal symbiont abundance and bleaching status, but depend on coral species and bacterial community composition. Furthermore, coral-derived superoxide concentrations ranged from levels below bulk seawater up to ~120 nM, some of the highest superoxide concentrations observed in marine systems. Overall, these results unveil the ability of corals and/or their microbiomes to regulate superoxide in their immediate surroundings, which suggests species-specific roles of superoxide in coral health and physiology.

  9. Species-specific control of external superoxide levels by the coral holobiont during a natural bleaching event

    PubMed Central

    Diaz, Julia M.; Hansel, Colleen M.; Apprill, Amy; Brighi, Caterina; Zhang, Tong; Weber, Laura; McNally, Sean; Xun, Liping

    2016-01-01

    The reactive oxygen species superoxide (O2·−) is both beneficial and detrimental to life. Within corals, superoxide may contribute to pathogen resistance but also bleaching, the loss of essential algal symbionts. Yet, the role of superoxide in coral health and physiology is not completely understood owing to a lack of direct in situ observations. By conducting field measurements of superoxide produced by corals during a bleaching event, we show substantial species-specific variation in external superoxide levels, which reflect the balance of production and degradation processes. Extracellular superoxide concentrations are independent of light, algal symbiont abundance and bleaching status, but depend on coral species and bacterial community composition. Furthermore, coral-derived superoxide concentrations ranged from levels below bulk seawater up to ∼120 nM, some of the highest superoxide concentrations observed in marine systems. Overall, these results unveil the ability of corals and/or their microbiomes to regulate superoxide in their immediate surroundings, which suggests species-specific roles of superoxide in coral health and physiology. PMID:27924868

  10. Effects of disturbance on coral communities: bleaching in Moorea, French Polynesia

    NASA Astrophysics Data System (ADS)

    Gleason, M. G.

    1993-11-01

    This study examines patterns of susceptibility and short-term recovery of corals from bleaching. A mass coral bleaching event began in March, 1991 on reefs in Moorea, French Polynesia and affected corals on the shallow barrier reef and to >20 m depth on the outer forereef slope. There were significant differences in the effect of the bleaching among common coral genera, with Acropora, Montastrea, Montipora, and Pocillopora more affected than Porites, Pavona, leptastrea or Millepora. Individual colonies of the common species of Acropora and Pocillopora were marked and their fate assessed on a subsequent survey in August, 1991 to determine rates of recovery and mortality. Ninety-six percent of Acropora spp. showed some degree of bleaching compared to 76% of Pocillopora spp. From March to August mortality of bleached colonies of Pocillopora was 17%, 38% recovered completely, and many suffered some partial mortality of the tissue. In contrast, 63% of the Acropora spp. died, and about 10% recovered completely. Generally, those colonies with less than 50% of the colony area affected by the bleaching recovered at a higher rate than did those with more severe bleaching. Changes in community composition four months after the event began included a significant decrease only in crustose algae and an increase in cover of filamentous algae, much of which occupied plate-like and branching corals that had died in the bleaching event. Total coral cover and cover of susceptible coral genera had declined, but not significantly, after the event.

  11. Species-specific trends in the reproductive output of corals across environmental gradients and bleaching histories.

    PubMed

    Howells, Emily J; Ketchum, Remi N; Bauman, Andrew G; Mustafa, Yasmine; Watkins, Kristina D; Burt, John A

    2016-04-30

    Coral populations in the Persian Gulf have a reputation for being some of the toughest in the world yet little is known about the energetic constraints of living under temperature and salinity extremes. Energy allocation for sexual reproduction in Gulf corals was evaluated relative to conspecifics living under milder environmental conditions in the Oman Sea. Fecundity was depressed at Gulf sites in two Indo-Pacific merulinid species (Cyphastrea microphthalma and Platygyra daedalea) but not in a regionally endemic acroporid (Acropora downingi). Gulf populations of each species experienced high temperature bleaching at the onset of gametogenesis in the study but fecundity was only negatively impacted in P. daedalea and A. downingi. Large population sizes of C. microphthalma and P. daedalea in the Gulf are expected to buffer reductions on colony-level fecundity. However, depleted population sizes of A. downingi at some Gulf sites equate to low reef-wide fecundity and likely impede outcrossing success.

  12. 78 FR 63941 - Endangered and Threatened Wildlife; 90-Day Finding on a Petition To List 23 Species of Corals as...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-25

    ... WildEarth Guardians to list 81 marine species as threatened or endangered under the ESA and to...). Species Description Most of the petitioned coral species are shallow water, reef- building anthozoan... offers no species-specific life history, abundance, or threat information (see discussion of...

  13. Abundance and composition of juvenile corals reveals divergent trajectories for coral assemblages across the United Arab Emirates.

    PubMed

    Pratchett, Morgan S; Baird, Andrew H; Bauman, Andrew G; Burt, John A

    2017-01-30

    Marked shifts in the composition of coral assemblages are occurring at many locations, but it is unknown whether these are permanent shifts reinforced by patterns of population replenishment. This study examined the composition of juvenile coral assemblages across the United Arab Emirates (UAE). Densities of juvenile corals varied significantly among locations, but were highest where coral cover was highest. Juvenile coral assemblages within the Persian Gulf were dominated by Porites, while no Acropora were recorded. We expect therefore, continued declines in Acropora abundance, while observed dominance of Porites is likely to persist. In the Oman Sea, Pocillopora was the dominant juvenile coral, with Acropora and Stylophora also recorded. This study shows that taxonomic differences in replenishment are reinforcing temporal shifts in coral composition within the southern Persian Gulf, but not in the Oman Sea. Differences in environmental conditions and disturbance regimes likely explain the divergent responses between regions.

  14. Favia Corals: a New Paleoclimate Archive

    NASA Astrophysics Data System (ADS)

    Miller, S. J.; Cobb, K. M.; Grothe, P. R.; Chen, T.; Sayani, H. R.; Lynch-Stieglitz, J.; Townsend, K. J.; Edwards, R. L.; Cheng, H.; Lu, Y.; Deocampo, D.

    2015-12-01

    Projections of future climate change contain large uncertainties stemming from our inability to confirm long-term trends in climate models with short instrumental records. Fossil corals are an important archive of past climate changes in the tropical oceans as oxygen isotopic ratios (δ18O) in their skeletons reflect ambient ocean temperature and salinity during the time they grew. In particular, El Niño/Southern Oscillation (ENSO) is a natural phenomenon with a complex array of sensitivities to climate change, rendering any future projections of its variability highly uncertain. The long-term behavior of ENSO and lower-frequency Pacific climate variability is recorded by annually banded fossil corals, providing insight into both natural and anthropogenic climate changes in this under-sampled region (Hughen et al. 1999; Tudhope et al. 2001; Cobb et al. 2003; Cobb et al. 2013). To date, most coral-based reconstructions have utilized cores from the genus Porites, owing its regular, concentric growth bands and fast growth-rates that allow for the generation of up to 20 samples per year of coral growth. However, this genus is neither evenly distributed across the tropics nor continuously available within the fossil record, so there is a pressing need to expand the types of corals available for reconstruction. Here, we test Favia species from Kiritimati Island (2°N, 157°W) as a paleoclimate recorder by comparing different δ18O timeseries from within a single coral as well as across multiple corals with instrumental sea-surface temperature (SST). We find significant and consistent differences between coral δ18O profiles sampled along thecal versus septa walls, and show that δ18O in the thecal wall is more reproducible, and more coherent with SST. Slow growth rates (8-10mm/yr), and small inter-colony δ18O offsets suggest that Favia may be an untapped climate archive that is capable of providing robust constraints on natural climate variability in the tropical

  15. Spatial variation in abundance, size and orientation of juvenile corals related to the biomass of parrotfishes on the Great Barrier Reef, Australia.

    PubMed

    Trapon, Melanie L; Pratchett, Morgan S; Hoey, Andrew S

    2013-01-01

    For species with complex life histories such as scleractinian corals, processes occurring early in life can greatly influence the number of individuals entering the adult population. A plethora of studies have examined settlement patterns of coral larvae, mostly on artificial substrata, and the composition of adult corals across multiple spatial and temporal scales. However, relatively few studies have examined the spatial distribution of small (≤50 mm diameter) sexually immature corals on natural reef substrata. We, therefore, quantified the variation in the abundance, composition and size of juvenile corals (≤50 mm diameter) among 27 sites, nine reefs, and three latitudes spanning over 1000 km on Australia's Great Barrier Reef. Overall, 2801 juveniles were recorded with a mean density of 6.9 (±0.3 SE) ind.m(-2), with Acropora, Pocillopora, and Porites accounting for 84.1% of all juvenile corals surveyed. Size-class structure, orientation on the substrate and taxonomic composition of juvenile corals varied significantly among latitudinal sectors. The abundance of juvenile corals varied both within (6-13 ind.m(-2)) and among reefs (2.8-11.1 ind.m(-2)) but was fairly similar among latitudes (6.1-8.2 ind.m(-2)), despite marked latitudinal variation in larval supply and settlement rates previously found at this scale. Furthermore, the density of juvenile corals was negatively correlated with the biomass of scraping and excavating parrotfishes across all sites, revealing a potentially important role of parrotfishes in determining distribution patterns of juvenile corals on the Great Barrier Reef. While numerous studies have advocated the importance of parrotfishes for clearing space on the substrate to facilitate coral settlement, our results suggest that at high biomass they may have a detrimental effect on juvenile coral assemblages. There is, however, a clear need to directly quantify rates of mortality and growth of juvenile corals to understand the relative

  16. Coral Diseases Following Massive Bleaching in 2005 Cause 60 Percent Decline in Coral Cover and Mortality of the Threatened Species, Acropora Palmata, on Reefs in the U.S. Virgin Islands

    USGS Publications Warehouse

    Rogers, Caroline S.

    2008-01-01

    Record-high seawater temperatures and calm seas in the summer of 2005 led to the most severe coral bleaching (greater than 90 percent bleached coral cover) ever observed in the U.S. Virgin Islands (USVI) (figs. 1 and 2). All but a few coral species bleached, including the threatened species, Acropora palmata. Bleaching was seen from the surface to depths over 20 meters.

  17. A Compartmental Comparison of Major Lipid Species in a Coral-Symbiodinium Endosymbiosis: Evidence that the Coral Host Regulates Lipogenesis of Its Cytosolic Lipid Bodies.

    PubMed

    Chen, Hung-Kai; Song, Shin-Ni; Wang, Li-Hsueh; Mayfield, Anderson B; Chen, Yi-Jyun; Chen, Wan-Nan U; Chen, Chii-Shiarng

    2015-01-01

    The lipid body (LB) formation in the host coral gastrodermal cell cytoplasm is a hallmark of the coral-Symbiodinium endosymbiosis, and such lipid-based entities are not found in endosymbiont-free cnidarian cells. Therefore, the elucidation of lipogenesis regulation in LBs and how it is related to the lipid metabolism of the host and endosymbiont could provide direct insight to understand the symbiosis mechanism. Herein, the lipid composition of host cells of the stony coral Euphyllia glabrescens, as well as that of their cytoplasmic LBs and in hospite Symbiodinium populations, was examined by high performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GC/MS), and six major lipid species were identified: wax esters, sterol esters, triacylglycerols, cholesterols, free fatty acids, and phospholipids. Their concentrations differed significantly between host coral cells, LBs, and Symbiodinium, suggesting compartmental regulation. WE were only present in the host coral and were particularly highly concentrated in LBs. Amongst the four species of WE, the monoene R = C18:1/R = C16 was found to be LB-specific and was not present in the host gastrodermal cell cytoplasm. Furthermore, the acyl pool profiles of the individual LB lipid species were more similar, but not equal to, those of the host gastrodermal cells in which they were located, indicating partially autonomous lipid metabolism in these LBs. Nevertheless, given the overall similarity in the host gastrodermal cell and LB lipid profiles, these data suggest that a significant portion of the LB lipids may be of host coral origin. Finally, lipid profiles of the in hospite Symbiodinium populations were significantly distinct from those of the cultured Symbiodinium, potentially suggesting a host regulation effect that may be fundamental to lipid metabolism in endosymbiotic associations involving clade C Symbiodinium.

  18. A Compartmental Comparison of Major Lipid Species in a Coral-Symbiodinium Endosymbiosis: Evidence that the Coral Host Regulates Lipogenesis of Its Cytosolic Lipid Bodies

    PubMed Central

    Chen, Hung-Kai; Song, Shin-Ni; Wang, Li-Hsueh; Mayfield, Anderson B.; Chen, Yi-Jyun; Chen, Wan-Nan U.; Chen, Chii-Shiarng

    2015-01-01

    The lipid body (LB) formation in the host coral gastrodermal cell cytoplasm is a hallmark of the coral-Symbiodinium endosymbiosis, and such lipid-based entities are not found in endosymbiont-free cnidarian cells. Therefore, the elucidation of lipogenesis regulation in LBs and how it is related to the lipid metabolism of the host and endosymbiont could provide direct insight to understand the symbiosis mechanism. Herein, the lipid composition of host cells of the stony coral Euphyllia glabrescens, as well as that of their cytoplasmic LBs and in hospite Symbiodinium populations, was examined by high performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GC/MS), and six major lipid species were identified: wax esters, sterol esters, triacylglycerols, cholesterols, free fatty acids, and phospholipids. Their concentrations differed significantly between host coral cells, LBs, and Symbiodinium, suggesting compartmental regulation. WE were only present in the host coral and were particularly highly concentrated in LBs. Amongst the four species of WE, the monoene R = C18:1/R = C16 was found to be LB-specific and was not present in the host gastrodermal cell cytoplasm. Furthermore, the acyl pool profiles of the individual LB lipid species were more similar, but not equal to, those of the host gastrodermal cells in which they were located, indicating partially autonomous lipid metabolism in these LBs. Nevertheless, given the overall similarity in the host gastrodermal cell and LB lipid profiles, these data suggest that a significant portion of the LB lipids may be of host coral origin. Finally, lipid profiles of the in hospite Symbiodinium populations were significantly distinct from those of the cultured Symbiodinium, potentially suggesting a host regulation effect that may be fundamental to lipid metabolism in endosymbiotic associations involving clade C Symbiodinium. PMID:26218797

  19. Flexible associations between Pocillopora corals and Symbiodinium limit utility of symbiosis ecology in defining species

    NASA Astrophysics Data System (ADS)

    Cunning, R.; Glynn, P. W.; Baker, A. C.

    2013-09-01

    Corals in the genus Pocillopora are the primary framework builders of eastern tropical Pacific (ETP) reefs. These corals typically associate with algal symbionts (genus Symbiodinium) in clade C and/or D, with clade D associations having greater thermal tolerance and resistance to bleaching. Recently, cryptic "species" delineations within both Pocillopora and Symbiodinium have been suggested, with host-symbiont specificity used as a supporting taxonomic character in both genera. In particular, it has been suggested that three lineages of Pocillopora (types 1-3) exist in the ETP, of which type 1 is the exclusive host of heat-tolerant Symbiodinium D1. This host specificity has been used to support the species name " Symbiodinium glynni" for this symbiont. To validate these host-symbiont relationships and their taxonomic utility, we identified Pocillopora types and their associated Symbiodinium at three sites in the ETP. We found greater flexibility in host-symbiont combinations than previously reported, with both Pocillopora types 1 and 3 able to host and be dominated by Symbiodinium in clade C or D. The prevalence of certain combinations did vary among sites, showing that a gradient of specificity exists which may be mediated by evolutionary relationships and environmental disturbance history. However, these results limit the utility of apparent host-symbiont specificity (which may have been a result of undersampling) in defining species boundaries in either corals or Symbiodinium. They also suggest that a greater diversity of corals may benefit from the thermal tolerance of clade D symbionts, affirming the need to conserve Pocillopora across its entire geographic and environmental range.

  20. Multi-species spawning synchrony within scleractinian coral assemblages in the Red Sea

    NASA Astrophysics Data System (ADS)

    Bouwmeester, J.; Baird, A. H.; Chen, C. J.; Guest, J. R.; Vicentuan, K. C.; Berumen, M. L.

    2015-03-01

    Early work on coral reproduction in the far northern Red Sea suggested that the spawning times of ecologically abundant species did not overlap, unlike on the Great Barrier Reef where many species spawn with high synchrony. In contrast, recent work in the northern and central Red Sea indicates a high degree of synchrony in the reproductive condition of Acropora species: over 90 % of species sampled in April/May contain mature gametes. However, it has yet to be determined when most Acropora release their gametes. In addition, there is a lack of data for other ecologically important scleractinian species such as merulinids and poritids. Here, we document the date and time of spawning for 51 species in the central Red Sea over three consecutive years, and the month of spawning for an additional 17 species inferred from the presence of mature gametes. Spawning occurs on nights around the full moon, the spawning season lasts at least 4 months from April until July, and observations are consistent with the few other records from the Red Sea. The number of Acropora species spawning was highest in April with 13 species spawning two nights before the full moon in 2011, 13 species spawning on the night of the full moon in 2012, and eight species spawning four nights after the full moon in 2013. The total number of species spawning was high in April, May, and June and involved 15-19 species per month in 2012. Only four species spawned in July 2012. Few regions worldwide have been similarly sampled and include the Philippines, Okinawa in Japan, and Palau, where spawning patterns are very similar to those in the central Red Sea and where corals spawn on nights around the full moon over a period of 3-4 months. In particular, in all four locations, Acropora are among the first species to spawn. Our results add to a growing body of evidence indicating that multi-species spawning synchrony is a feature of all speciose coral assemblages.

  1. Short-term ecological consequences of a major oil spill on Panamanian subtidal reef corals

    NASA Astrophysics Data System (ADS)

    Guzmán, Héctor M.; Jackson, Jeremy B. C.; Weil, Ernesto

    1991-07-01

    A major oil spill (8,000,000 liters; 50,000 barrels) occurred in Bahía Las Minas on the Caribbean coast of Panama in April 1986, and oil slicks from the refinery landfill and mangroves were still common there after 21/2 years. We studied short-term effects of the spill on common shallow subtidal reef corals, at the individual, population, and community levels. Numbers of corals, total coral cover, and species diversity based on cover decreased significantly with increased amounts of oiling. Cover of the large branching coral Acropora palmata decreased most. Frequency and size of recent injuries on massive corals increased with level of oiling, particularly for Siderastrea siderea. Growth of three massive species ( Porites astreoides, Diploria strigosa, and Montastrea annularis, but not S. siderea) was less at oiled reefs in the year of the spill than during the 9 previous years. Subtidal coral reefs, particularly those along protected coasts, may suffer extensive damage from chronic exposure after major oil spills.

  2. Tracking Transmission of Apicomplexan Symbionts in Diverse Caribbean Corals

    PubMed Central

    Kirk, Nathan L.; Ritson-Williams, Raphael; Coffroth, Mary Alice; Miller, Margaret W.; Fogarty, Nicole D.; Santos, Scott R.

    2013-01-01

    Symbionts in each generation are transmitted to new host individuals either vertically (parent to offspring), horizontally (from exogenous sources), or a combination of both. Scleractinian corals make an excellent study system for understanding patterns of symbiont transmission since they harbor diverse symbionts and possess distinct reproductive modes of either internal brooding or external broadcast spawning that generally correlate with vertical or horizontal transmission, respectively. Here, we focused on the under-recognized, but apparently widespread, coral-associated apicomplexans (Protista: Alveolata) to determine if symbiont transmission depends on host reproductive mode. Specifically, a PCR-based assay was utilized towards identifying whether planula larvae and reproductive adults from brooding and broadcast spawning scleractinian coral species in Florida and Belize harbored apicomplexan DNA. Nearly all (85.5%; n = 85/89) examined planulae of five brooding species (Porites astreoides, Agaricia tenuifolia, Agaricia agaricites, Favia fragum, Mycetophyllia ferox) and adults of P. astreoides were positive for apicomplexan DNA. In contrast, no (n = 0/10) apicomplexan DNA was detected from planulae of four broadcast spawning species (Acropora cervicornis, Acropora palmata, Pseudodiploria strigosa, and Orbicella faveolata) and rarely in gametes (8.9%; n = 5/56) of these species sampled from the same geographical range as the brooding species. In contrast, tissue samples from nearly all (92.0%; n = 81/88) adults of the broadcast spawning species A. cervicornis, A. palmata and O. faveolata harbored apicomplexan DNA, including colonies whose gametes and planulae tested negative for these symbionts. Taken together, these data suggest apicomplexans are transmitted vertically in these brooding scleractinian coral species while the broadcast spawning scleractinian species examined here acquire these symbionts horizontally. Notably, these transmission patterns are

  3. Can heterotrophic uptake of dissolved organic carbon and zooplankton mitigate carbon budget deficits in annually bleached corals?

    NASA Astrophysics Data System (ADS)

    Levas, Stephen; Grottoli, Andréa G.; Schoepf, Verena; Aschaffenburg, Matthew; Baumann, Justin; Bauer, James E.; Warner, Mark E.

    2016-06-01

    Annual coral bleaching events due to increasing sea surface temperatures are predicted to occur globally by the mid-century and as early as 2025 in the Caribbean, and severely impact coral reefs. We hypothesize that heterotrophic carbon (C) in the form of zooplankton and dissolved organic carbon (DOC) is a significant source of C to bleached corals. Thus, the ability to utilize multiple pools of fixed carbon and/or increase the amount of fixed carbon acquired from one or more pools of fixed carbon (defined here as heterotrophic plasticity) could underlie coral acclimatization and persistence under future ocean-warming scenarios. Here, three species of Caribbean coral— Porites divaricata, P. astreoides, and Orbicella faveolata—were experimentally bleached for 2.5 weeks in two successive years and allowed to recover in the field. Zooplankton feeding was assessed after single and repeat bleaching, while DOC fluxes and the contribution of DOC to the total C budget were determined after single bleaching, 11 months on the reef, and repeat bleaching. Zooplankton was a large C source for P. astreoides, but only following single bleaching. DOC was a source of C for single-bleached corals and accounted for 11-36 % of daily metabolic demand (CHARDOC), but represented a net loss of C in repeat-bleached corals. In repeat-bleached corals, DOC loss exacerbated the negative C budgets in all three species. Thus, the capacity for heterotrophic plasticity in corals is compromised under annual bleaching, and heterotrophic uptake of DOC and zooplankton does not mitigate C budget deficits in annually bleached corals. Overall, these findings suggest that some Caribbean corals may be more susceptible to repeat bleaching than to single bleaching due to a lack of heterotrophic plasticity, and coral persistence under increasing bleaching frequency may ultimately depend on other factors such as energy reserves and symbiont shuffling.

  4. Concordance between genetic and species diversity in coral reef fishes across the Pacific Ocean biodiversity gradient.

    PubMed

    Messmer, Vanessa; Jones, Geoffrey P; Munday, Philip L; Planes, Serge

    2012-12-01

    The relationship between genetic diversity and species diversity provides insights into biogeography and historic patterns of evolution and is critical for developing contemporary strategies for biodiversity conservation. Although concordant large-scale clines in genetic and species diversity have been described for terrestrial organisms, whether these parameters co-vary in marine species remains largely unknown. We examined patterns of genetic diversity for 11 coral reef fish species sampled at three locations across the Pacific Ocean species diversity gradient (Australia: ∼1600 species; New Caledonia: ∼1400 species; French Polynesia: ∼800 species). Combined genetic diversity for all 11 species paralleled the decline in species diversity from West to East, with French Polynesia exhibiting lowest total haplotype and nucleotide diversities. Haplotype diversity consistently declined toward French Polynesia in all and nucleotide diversity in the majority of species. The French Polynesian population of most species also exhibited significant genetic differentiation from populations in the West Pacific. A number of factors may have contributed to the general positive correlation between genetic and species diversity, including location and time of species origin, vicariance events, reduced gene flow with increasing isolation, and decreasing habitat area from West to East. However, isolation and habitat area, resulting in reduced population size, are likely to be the most influential.

  5. Fishing down the largest coral reef fish species.

    PubMed

    Fenner, Douglas

    2014-07-15

    Studies on remote, uninhabited, near-pristine reefs have revealed surprisingly large populations of large reef fish. Locations such as the northwestern Hawaiian Islands, northern Marianas Islands, Line Islands, U.S. remote Pacific Islands, Cocos-Keeling Atoll and Chagos archipelago have much higher reef fish biomass than islands and reefs near people. Much of the high biomass of most remote reef fish communities lies in the largest species, such as sharks, bumphead parrots, giant trevally, and humphead wrasse. Some, such as sharks and giant trevally, are apex predators, but others such as bumphead parrots and humphead wrasse, are not. At many locations, decreases in large reef fish species have been attributed to fishing. Fishing is well known to remove the largest fish first, and a quantitative measure of vulnerability to fishing indicates that large reef fish species are much more vulnerable to fishing than small fish. The removal of large reef fish by fishing parallels the extinction of terrestrial megafauna by early humans. However large reef fish have great value for various ecological roles and for reef tourism.

  6. Fine-Scale Skeletal Banding Can Distinguish Symbiotic from Asymbiotic Species among Modern and Fossil Scleractinian Corals.

    PubMed

    Frankowiak, Katarzyna; Kret, Sławomir; Mazur, Maciej; Meibom, Anders; Kitahara, Marcelo V; Stolarski, Jarosław

    2016-01-01

    Understanding the evolution of scleractinian corals on geological timescales is key to predict how modern reef ecosystems will react to changing environmental conditions in the future. Important to such efforts has been the development of several skeleton-based criteria to distinguish between the two major ecological groups of scleractinians: zooxanthellates, which live in symbiosis with dinoflagellate algae, and azooxanthellates, which lack endosymbiotic dinoflagellates. Existing criteria are based on overall skeletal morphology and bio/geo-chemical indicators-none of them being particularly robust. Here we explore another skeletal feature, namely fine-scale growth banding, which differs between these two groups of corals. Using various ultra-structural imaging techniques (e.g., TEM, SEM, and NanoSIMS) we have characterized skeletal growth increments, composed of doublets of optically light and dark bands, in a broad selection of extant symbiotic and asymbiotic corals. Skeletons of zooxanthellate corals are characterized by regular growth banding, whereas in skeletons of azooxanthellate corals the growth banding is irregular. Importantly, the regularity of growth bands can be easily quantified with a coefficient of variation obtained by measuring bandwidths on SEM images of polished and etched skeletal surfaces of septa and/or walls. We find that this coefficient of variation (lower values indicate higher regularity) ranges from ~40 to ~90% in azooxanthellate corals and from ~5 to ~15% in symbiotic species. With more than 90% (28 out of 31) of the studied corals conforming to this microstructural criterion, it represents an easy and robust method to discriminate between zooxanthellate and azooxanthellate corals. This microstructural criterion has been applied to the exceptionally preserved skeleton of the Triassic (Norian, ca. 215 Ma) scleractinian Volzeia sp., which contains the first example of regular, fine-scale banding of thickening deposits in a fossil coral

  7. Fine-Scale Skeletal Banding Can Distinguish Symbiotic from Asymbiotic Species among Modern and Fossil Scleractinian Corals

    PubMed Central

    Frankowiak, Katarzyna; Kret, Sławomir; Mazur, Maciej; Meibom, Anders; Kitahara, Marcelo V.; Stolarski, Jarosław

    2016-01-01

    Understanding the evolution of scleractinian corals on geological timescales is key to predict how modern reef ecosystems will react to changing environmental conditions in the future. Important to such efforts has been the development of several skeleton-based criteria to distinguish between the two major ecological groups of scleractinians: zooxanthellates, which live in symbiosis with dinoflagellate algae, and azooxanthellates, which lack endosymbiotic dinoflagellates. Existing criteria are based on overall skeletal morphology and bio/geo-chemical indicators—none of them being particularly robust. Here we explore another skeletal feature, namely fine-scale growth banding, which differs between these two groups of corals. Using various ultra-structural imaging techniques (e.g., TEM, SEM, and NanoSIMS) we have characterized skeletal growth increments, composed of doublets of optically light and dark bands, in a broad selection of extant symbiotic and asymbiotic corals. Skeletons of zooxanthellate corals are characterized by regular growth banding, whereas in skeletons of azooxanthellate corals the growth banding is irregular. Importantly, the regularity of growth bands can be easily quantified with a coefficient of variation obtained by measuring bandwidths on SEM images of polished and etched skeletal surfaces of septa and/or walls. We find that this coefficient of variation (lower values indicate higher regularity) ranges from ~40 to ~90% in azooxanthellate corals and from ~5 to ~15% in symbiotic species. With more than 90% (28 out of 31) of the studied corals conforming to this microstructural criterion, it represents an easy and robust method to discriminate between zooxanthellate and azooxanthellate corals. This microstructural criterion has been applied to the exceptionally preserved skeleton of the Triassic (Norian, ca. 215 Ma) scleractinian Volzeia sp., which contains the first example of regular, fine-scale banding of thickening deposits in a fossil

  8. Character release following extinction in a Caribbean reef coral species complex.

    PubMed

    Pandolfi, John M; Lovelock, Catherine E; Budd, Ann F

    2002-03-01

    The Pleistocene extinction of the widespread organ-pipe Montastraea coral had measurable morphological and ecological effects on surviving lineages of the Montastraea "annularis" species complex. Extinction of the organ-pipe Montastraea occurred after more than 500,000 years of dominance in the shallow-water reef habitat of Barbados. Extinction resulted in a morphological shift of the columnar Montastraea lineage from thick to thin columns in modern reef environments. Pleistocene colonies of the columnar morphotype sympatric with organ-pipe Montastraea showed greater column widths than those in allopatry. We subjected our data to a number of criteria for interpreting the morphological shift as character release following lifting of competitive pressure after extinction. The morphological differences do not appear to be due either to chance or to physical properties of the marine environment. Differential local extinction and recolonization of four members of the species complex did not occur on Barbados, so that the species coexisted and appear to have coevolved between more than 600,000 and 82,000 years ago. The morphological shift is related to coral growth form and growth rate, and thus reflects the acquisition of a primary resource in corals--light. Character release occurred at the same oceanic Caribbean island (Barbados) where environments have fluctuated with similar variance throughout the period of coexistence. Not only has competition among living members of the Montastraea "annularis" species complex been convincingly demonstrated, but trends in relative abundance among fossil members of the species complex strongly suggest that a competitive hierarchy was operating during their Pleistocene coexistence on Barbados. We also observed an ecological analogue to character release on another Caribbean island. Curaçao. The distribution and abundance of living columnar M. annularis s.s. and massive M. faveolata from the leeward reef crest in Curaçao is greater

  9. Sponge erosion under acidification and warming scenarios: differential impacts on living and dead coral.

    PubMed

    Stubler, Amber D; Furman, Bradley T; Peterson, Bradley J

    2015-11-01

    Ocean acidification will disproportionately impact the growth of calcifying organisms in coral reef ecosystems. Simultaneously, sponge bioerosion rates have been shown to increase as seawater pH decreases. We conducted a 20-week experiment that included a 4-week acclimation period with a high number of replicate tanks and a fully orthogonal design with two levels of temperature (ambient and +1 °C), three levels of pH (8.1, 7.8, and 7.6), and two levels of boring sponge (Cliona varians, present and absent) to account for differences in sponge attachment and carbonate change for both living and dead coral substrate (Porites furcata). Net coral calcification, net dissolution/bioerosion, coral and sponge survival, sponge attachment, and sponge symbiont health were evaluated. Additionally, we used the empirical data from the experiment to develop a stochastic simulation of carbonate change for small coral clusters (i.e., simulated reefs). Our findings suggest differential impacts of temperature, pH and sponge presence for living and dead corals. Net coral calcification (mg CaCO3  cm(-2)  day(-1) ) was significantly reduced in treatments with increased temperature (+1 °C) and when sponges were present; acidification had no significant effect on coral calcification. Net dissolution of dead coral was primarily driven by pH, regardless of sponge presence or seawater temperature. A reevaluation of the current paradigm of coral carbonate change under future acidification and warming scenarios should include ecologically relevant timescales, species interactions, and community organization to more accurately predict ecosystem-level response to future conditions.

  10. Species delimitation in the coral genus Goniopora (Scleractinia, Poritidae) from the Saudi Arabian Red Sea.

    PubMed

    Terraneo, Tullia I; Benzoni, Francesca; Arrigoni, Roberto; Berumen, Michael L

    2016-09-01

    Variable skeletal morphology, genotype induced plasticity, and homoplasy of skeletal structures have presented major challenges for scleractinian coral taxonomy and systematics since the 18th century. Although the recent integration of genetic and micromorphological data is helping to clarify the taxonomic confusion within the order, phylogenetic relationships and species delimitation within most coral genera are still far from settled. In the present study, the species boundaries in the scleractinian coral genus Goniopora were investigated using 199 colonies from the Saudi Arabian Red Sea and sequencing of four molecular markers: the mitochondrial intergenic spacer between CytB and NAD2, the nuclear ribosomal ITS region, and two single-copy nuclear genes (ATPsβ and CalM). DNA sequence data were analyzed using a variety of methods and exploratory species-delimitation tools. The results were broadly congruent in identifying five distinct molecular lineages within the sequenced Goniopora samples: G. somaliensis/G. savignyi, G. djiboutiensis/G. lobata, G. stokesi, G. albiconus/G. tenuidens, and G. minor/G. gracilis. Although the traditional macromorphological characters used to identify these nine morphospecies were not able to discriminate the obtained molecular clades, informative micromorphological and microstructural features (such as the micro-ornamentation and the arrangement of the columella) were recovered among the five lineages. Moreover, unique in vivo morphologies were associated with the genetic-delimited lineages, further supporting the molecular findings. This study represents the first attempt to identify species boundaries within Goniopora using a combined morpho-molecular approach. The obtained data establish a basis for future taxonomic revision of the genus, which should include colonies across its entire geographical distribution in the Indo-Pacific.

  11. The Point Count Transect Method for Estimates of Biodiversity on Coral Reefs: Improving the Sampling of Rare Species.

    PubMed

    Roberts, T Edward; Bridge, Thomas C; Caley, M Julian; Baird, Andrew H

    2016-01-01

    Understanding patterns in species richness and diversity over environmental gradients (such as altitude and depth) is an enduring component of ecology. As most biological communities feature few common and many rare species, quantifying the presence and abundance of rare species is a crucial requirement for analysis of these patterns. Coral reefs present specific challenges for data collection, with limitations on time and site accessibility making efficiency crucial. Many commonly used methods, such as line intercept transects (LIT), are poorly suited to questions requiring the detection of rare events or species. Here, an alternative method for surveying reef-building corals is presented; the point count transect (PCT). The PCT consists of a count of coral colonies at a series of sample stations, located at regular intervals along a transect. In contrast the LIT records the proportion of each species occurring under a transect tape of a given length. The same site was surveyed using PCT and LIT to compare species richness estimates between the methods. The total number of species increased faster per individual sampled and unit of time invested using PCT. Furthermore, 41 of the 44 additional species recorded by the PCT occurred ≤ 3 times, demonstrating the increased capacity of PCT to detect rare species. PCT provides a more accurate estimate of local-scale species richness than the LIT, and is an efficient alternative method for surveying reef corals to address questions associated with alpha-diversity, and rare or incidental events.

  12. Dongsha Atoll: A potential thermal refuge for reef-building corals in the South China Sea.

    PubMed

    Tkachenko, Konstantin S; Soong, Keryea

    2017-04-04

    Dongsha Atoll (also known as the Pratas Islands), the northernmost atoll in the South China Sea, experiences two contrasting physical phenomena: repetitive anomalies of the sea surface temperature exceeding the coral bleaching threshold and regular effects of the world's strongest internal waves resulting in the rhythmic upwelling of cold deep waters at the outer reef slopes of the atoll. This unique combination may result in significant differences in coral species composition and structure between the lagoon and forereef. Surveys conducted in August-September 2016 at 12 study sites in the 2-15 m depth range at Dongsha Atoll revealed a clear spatial separation between 'thermally-susceptible' stony coral genera, including Acropora, Pocillopora and Montipora, which mainly inhabited the forereef, and 'thermally-resistant' genera, including massive Porites, foliaceous Echinopora, Pavona and Turbinaria, which mainly resided in the lagoon. The mean coral cover and species richness on the forereef were respectively 1.8 and 1.4 times higher than those in the lagoon (61.3% and 98 species on the forereef vs. 34.2% and 69 species in the lagoon). Coral mortality rates, expressed as the ratio of dead to live stony corals, showed the same pattern (0.4 in the lagoon vs. 0.009 on the forereef). Furthermore, in a laboratory experiment, 'thermally-susceptible' taxa from the lagoon, (e.g. Pocillopora verrucosa and P. damicornis), exhibited higher resistance to bleaching than did their counterparts from the forereef. The present findings indicate that Dongsha Atoll is a potential thermal refuge for reef-building corals in the northern South China Sea and reveal the development of resilience and resistance to bleaching in coral communities of the lagoon.

  13. Effects of two sediment types on the fluorescence yield of two Hawaiian scleractinian corals.

    PubMed

    Piniak, Gregory A

    2007-10-01

    This study used non-invasive pulse-amplitude modulated (PAM) fluorometry to measure the maximum fluorescence yield (F(v)/F(m)) of two Hawaiian scleractinian coral species exposed to short-term sedimentation stress. Beach sand or harbor mud was applied to coral fragments in a flow-through aquarium system for 0-45 h, and changes in F(v)/F(m) were measured as a function of sediment type and length of exposure. Corals were monitored for up to 90 h to document recovery after sediment removal. Sediment deposition significantly decreased F(v)/F(m) in both species and was a function of sediment type and time. Corals that received sediment for 30 h or more had the greatest reduction in yield and exhibited little recovery over the course of the experiment. Harbor mud caused a greater reduction in Porites lobata yield than beach sand, whereas both sediment types had equally deleterious effects on Montipora capitata. Colony morphology and sediment type were important factors in determining yield reduction--P. lobata minimized damage from coarse sand grains by passive sediment rejection or accumulation in depressions in the skeleton, and fluorescence yield decreased most in corals exposed to sticky harbor mud or in colonies with flattened morphologies. Species-specific differences could not be tested due to differences in colony morphology and surface area.

  14. Effects of two sediment types on the fluorescence yield of two Hawaiian scleractinian corals

    USGS Publications Warehouse

    Piniak, G.A.

    2007-01-01

    This study used non-invasive pulse-amplitude modulated (PAM) fluorometry to measure the maximum fluorescence yield (Fv/Fm) of two Hawaiian scleractinian coral species exposed to short-term sedimentation stress. Beach sand or harbor mud was applied to coral fragments in a flow-through aquarium system for 0-45 h, and changes in Fv/Fm were measured as a function of sediment type and length of exposure. Corals were monitored for up to 90 h to document recovery after sediment removal. Sediment deposition significantly decreased Fv/Fm in both species and was a function of sediment type and time. Corals that received sediment for 30 h or more had the greatest reduction in yield and exhibited little recovery over the course of the experiment. Harbor mud caused a greater reduction in Porites lobata yield than beach sand, whereas both sediment types had equally deleterious effects on Montipora capitata. Colony morphology and sediment type were important factors in determining yield reduction-P. lobata minimized damage from coarse sand grains by passive sediment rejection or accumulation in depressions in the skeleton, and fluorescence yield decreased most in corals exposed to sticky harbor mud or in colonies with flattened morphologies. Species-specific differences could not be tested due to differences in colony morphology and surface area. ?? 2007.

  15. Linking sewage pollution and water quality to spatial patterns of Porites lobata growth anomalies in Puako, Hawaii.

    PubMed

    Yoshioka, Reyn M; Kim, Catherine J S; Tracy, Allison M; Most, Rebecca; Harvell, C Drew

    2016-03-15

    Sewage pollution threatens the health of coastal populations and ecosystems, including coral reefs. We investigated spatial patterns of sewage pollution in Puako, Hawaii using enterococci concentrations and δ(15)N Ulva fasciata macroalgal bioassays to assess relationships with the coral disease Porites lobata growth anomalies (PGAs). PGA severity and enterococci concentrations were high, spatially variable, and positively related. Bioassay algal δ(15)N showed low sewage pollution at the reef edge while high values of resident algae indicated sewage pollution nearshore. Neither δ(15)N metric predicted PGA measures, though bioassay δ(15)N was negatively related to coral cover. Furthermore, PGA prevalence was much higher than previously recorded in Hawaii and the greater Indo-Pacific, highlighting Puako as an area of concern. Although further work is needed to resolve the relationship between sewage pollution and coral cover and disease, these results implicate sewage pollution as a contributor to diminished reef health.

  16. Light availability determines susceptibility of reef building corals to ocean acidification

    NASA Astrophysics Data System (ADS)

    Suggett, D. J.; Dong, L. F.; Lawson, T.; Lawrenz, E.; Torres, L.; Smith, D. J.

    2013-06-01

    Elevated seawater pCO2, and in turn ocean acidification (OA), is now widely acknowledged to reduce calcification and growth of reef building corals. As with other environmental factors (e.g., temperature and nutrients), light availability fundamentally regulates calcification and is predicted to change for future reef environments alongside elevated pCO2 via altered physical processes (e.g., sea level rise and turbidity); however, any potential role of light in regulating the OA-induced reduction of calcification is still unknown. We employed a multifactorial growth experiment to determine how light intensity and pCO2 together modify calcification for model coral species from two key genera, Acropora horrida and Porites cylindrica, occupying similar ecological niches but with different physiologies. We show that elevated pCO2 (OA)-induced losses of calcification in the light ( G L) but not darkness ( G D) were greatest under low-light growth conditions, in particular for A. horrida. High-light growth conditions therefore dampened the impact of OA upon G L but not G D. Gross photosynthesis ( P G) responded in a reciprocal manner to G L suggesting OA-relieved pCO2 limitation of P G under high-light growth conditions to effectively enhance G L. A multivariate analysis of past OA experiments was used to evaluate whether our test species responses were more widely applicable across their respective genera. Indeed, the light intensity for growth was identified as a significant factor influencing the OA-induced decline of calcification for species of Acropora but not Porites. Whereas low-light conditions can provide a refuge for hard corals from thermal and light stress, our study suggests that lower light availability will potentially increase the susceptibility of key coral species to OA.

  17. Multi-Scale Approach for Predicting Fish Species Distributions across Coral Reef Seascapes

    PubMed Central

    Pittman, Simon J.; Brown, Kerry A.

    2011-01-01

    Two of the major limitations to effective management of coral reef ecosystems are a lack of information on the spatial distribution of marine species and a paucity of data on the interacting environmental variables that drive distributional patterns. Advances in marine remote sensing, together with the novel integration of landscape ecology and advanced niche modelling techniques provide an unprecedented opportunity to reliably model and map marine species distributions across many kilometres of coral reef ecosystems. We developed a multi-scale approach using three-dimensional seafloor morphology and across-shelf location to predict spatial distributions for five common Caribbean fish species. Seascape topography was quantified from high resolution bathymetry at five spatial scales (5–300 m radii) surrounding fish survey sites. Model performance and map accuracy was assessed for two high performing machine-learning algorithms: Boosted Regression Trees (BRT) and Maximum Entropy Species Distribution Modelling (MaxEnt). The three most important predictors were geographical location across the shelf, followed by a measure of topographic complexity. Predictor contribution differed among species, yet rarely changed across spatial scales. BRT provided ‘outstanding’ model predictions (AUC = >0.9) for three of five fish species. MaxEnt provided ‘outstanding’ model predictions for two of five species, with the remaining three models considered ‘excellent’ (AUC = 0.8–0.9). In contrast, MaxEnt spatial predictions were markedly more accurate (92% map accuracy) than BRT (68% map accuracy). We demonstrate that reliable spatial predictions for a range of key fish species can be achieved by modelling the interaction between the geographical location across the shelf and the topographic heterogeneity of seafloor structure. This multi-scale, analytic approach is an important new cost-effective tool to accurately delineate essential fish habitat and support

  18. Leucothoe eltoni sp. n., a new species of commensal leucothoid amphipod from coral reefs in Raja Ampat, Indonesia (Crustacea, Amphipoda).

    PubMed

    Thomas, James Darwin

    2015-01-01

    A new species of leucothoid amphipod, Leucothoe eltoni sp. n., is described from coral reefs in Raja Ampat, Indonesia where it inhabits the branchial chambers of solitary tunicates. With an inflated first gnathopod superficially resembling the genus Paraleucothoe, this new species has a two-articulate maxilla 1 palp characteristic of the genus Leucothoe. While described from coral reef environments in tropical Indonesia and the Philippines, it is an established invasive species in the Hawaiian Islands. The most likely mode of introduction was a US Navy dry dock transported to Pearl Harbor in 1992 from Subic Bay, Philippines.

  19. Leucothoe eltoni sp. n., a new species of commensal leucothoid amphipod from coral reefs in Raja Ampat, Indonesia (Crustacea, Amphipoda)

    PubMed Central

    Thomas, James Darwin

    2015-01-01

    Abstract A new species of leucothoid amphipod, Leucothoe eltoni sp. n., is described from coral reefs in Raja Ampat, Indonesia where it inhabits the branchial chambers of solitary tunicates. With an inflated first gnathopod superficially resembling the genus Paraleucothoe, this new species has a two-articulate maxilla 1 palp characteristic of the genus Leucothoe. While described from coral reef environments in tropical Indonesia and the Philippines, it is an established invasive species in the Hawaiian Islands. The most likely mode of introduction was a US Navy dry dock transported to Pearl Harbor in 1992 from Subic Bay, Philippines. PMID:26448700

  20. Coral choreography

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    Viewers clicking onto the Waikiki Aquarium's “Coral Research Cam” any time during daylight hours in Hawaii can catch the latest action of three species of living corals (Acropora sp., Acropora elseyi,and Montipora digitata) and the yellow tang and blue tang fish swimming amongst them in an outdoor aquarium.Waikiki Aquarium Director Bruce Carlson says the camera is part of a new exhibit, “Corals Are Alive!,” which encourages people to view living corals close-up at the aquarium or via the Internet, in order to gain a better appreciation of the corals. “Hopefully through education and awareness, people will be more interested and willing to help with conservation efforts to preserve coral reefs,” says Carlson.

  1. The corallivorous flatworm Amakusaplana acroporae: an invasive species threat to coral reefs?

    NASA Astrophysics Data System (ADS)

    Hume, Benjamin C. C.; D'Angelo, Cecilia; Cunnington, Anna; Smith, Edward G.; Wiedenmann, Jörg

    2014-03-01

    Fatal infestations of land-based Acropora cultures with so-called Acropora- eating flatworms (AEFWs) are a global phenomenon. We evaluate the hypothesis that AEFWs represent a risk to coral reefs by studying the biology and the invasive potential of an AEFW strain from the UK. Molecular analyses identified this strain as Amakusaplana acroporae, a new species described from two US aquaria and one natural location in Australia. Our molecular data together with life history strategies described here suggest that this species accounts for most reported cases of AEFW infestations. We show that local parasitic activity impairs the light-acclimation capacity of the whole host colony. A. acroporae acquires excellent camouflage by harbouring photosynthetically competent, host-derived zooxanthellae and pigments of the green-fluorescent protein family. It shows a preference for Acropora valida but accepts a broad host range. Parasite survival in isolation (5-7 d) potentially allows for an invasion when introduced as non-native species in coral reefs.

  2. Sexual systems in scleractinian corals: an unusual pattern in the reef-building species Diploastrea heliopora

    NASA Astrophysics Data System (ADS)

    Guest, J. R.; Baird, A. H.; Goh, B. P. L.; Chou, L. M.

    2012-09-01

    The sexual system in corals refers to the spatial and temporal pattern of sexual function within an individual coral polyp, colony or population. Although information on sexual systems now exists for over 400 scleractinian species, data are still lacking for some important reef-building taxa. The vast majority of scleractinians are either simultaneous hermaphrodites or gonochoric with other sexual systems rarely occurring. Diploastrea heliopora is one of the most ubiquitous and easily recognised reef-building species in the Indo-West Pacific; however, surprisingly little is known about its reproductive biology. The aim of the present study was to examine the reproductive biology of D. heliopora colonies on chronically impacted, equatorial reefs south of Singapore. Here we show that in Singapore, D. heliopora is a broadcast spawner with predominantly gonochoric polyps. Colonies, however, contained male, female and a low proportion of cosexual polyps during the 14-month sampling period. The most plausible explanation for this is that polyps switch sexes with oogenic and spermatogenic cycles occasionally overlapping. This leads to colony level alternation of sex function within and between breeding seasons. While this sexual system is atypical for scleractinians, it supports molecular evidence that D. heliopora is phylogenetically distinct from species formerly in the family Faviidae.

  3. Tissue mortality by Caribbean ciliate infection and white band disease in three reef-building coral species

    PubMed Central

    Bastidas, Carolina; Croquer, Aldo

    2016-01-01

    Caribbean ciliate infection (CCI) and white band disease (WBD) are diseases that affect a multitude of coral hosts and are associated with rapid rates of tissue losses, thus contributing to declining coral cover in Caribbean reefs. In this study we compared tissue mortality rates associated to CCI in three species of corals with different growth forms: Orbicella faveolata (massive-boulder), O. annularis (massive-columnar) and Acropora cervicornis (branching). We also compared mortality rates in colonies of A. cervicornis bearing WBD and CCI. The study was conducted at two locations in Los Roques Archipelago National Park between April 2012 and March 2013. In A. cervicornis, the rate of tissue loss was similar between WBD (0.8 ± 1 mm/day, mean ± SD) and CCI (0.7 ± 0.9 mm/day). However, mortality rate by CCI in A. cervicornis was faster than in the massive species O. faveolata (0.5 ± 0.6 mm/day) and O. annularis (0.3 ± 0.3 mm/day). Tissue regeneration was at least fifteen times slower than the mortality rates for both diseases regardless of coral species. This is the first study providing coral tissue mortality and regeneration rates associated to CCI in colonies with massive morphologies, and it highlights the risks of further cover losses of the three most important reef-building species in the Caribbean. PMID:27547525

  4. Tissue mortality by Caribbean ciliate infection and white band disease in three reef-building coral species.

    PubMed

    Verde, Alejandra; Bastidas, Carolina; Croquer, Aldo

    2016-01-01

    Caribbean ciliate infection (CCI) and white band disease (WBD) are diseases that affect a multitude of coral hosts and are associated with rapid rates of tissue losses, thus contributing to declining coral cover in Caribbean reefs. In this study we compared tissue mortality rates associated to CCI in three species of corals with different growth forms: Orbicella faveolata (massive-boulder), O. annularis (massive-columnar) and Acropora cervicornis (branching). We also compared mortality rates in colonies of A. cervicornis bearing WBD and CCI. The study was conducted at two locations in Los Roques Archipelago National Park between April 2012 and March 2013. In A. cervicornis, the rate of tissue loss was similar between WBD (0.8 ± 1 mm/day, mean ± SD) and CCI (0.7 ± 0.9 mm/day). However, mortality rate by CCI in A. cervicornis was faster than in the massive species O. faveolata (0.5 ± 0.6 mm/day) and O. annularis (0.3 ± 0.3 mm/day). Tissue regeneration was at least fifteen times slower than the mortality rates for both diseases regardless of coral species. This is the first study providing coral tissue mortality and regeneration rates associated to CCI in colonies with massive morphologies, and it highlights the risks of further cover losses of the three most important reef-building species in the Caribbean.

  5. [Effect of herbivorous and corallivorous fishes on the survival of transplanted corals in the Colombian Caribbean].

    PubMed

    Chasqui-Velasco, Luis; Alvarado Ch, Elvira; Acero, Arturo; Zapata, Fernando A

    2007-01-01

    To examine the effects of herbivorous and corallivorous fishes on the survival of transplanted colonies of Montastraea annularis, Diploria labyrinthiformis and Porites astreoides, both transplanted and native colonies were full-cage enclosed and compared to open (uncaged) colonies, while caging effects were assessed with a partial-cage (roof treatment). To evaluate if transplant stress increased the corals availability to fish predation, comparisons of fish foraging intensity among transplanted versus native colonies were made. To determine the density of herbivorous and corallivorous fishes on the transplants area visual censuses were made. The transient herbivorous fishes (Scaridae and Acanthuridae) were the most abundant fishes, and the corallivorous fishes (mainly Chaetodontidae) were the scarcest. A negative effect of territorial herbivorous fishes on M annularis transplants survival was observed, mainly early on the study. Fish foraging intensity was similar on transplanted and native colonies, but differed among coral species, being lowest on D. labyrinthiformis. Fast macroalgal growth inside full-cages due to reduced fish grazing was observed. This caused partial bleaching and partial mortality in some colonies, mainly of P. astreoides. No significant difference in healthy tissue percentages among full-cage and uncaged colonies on M. annularis and D. labyrinthiformis was found, while in P. astreoides there were evilent differences. The results indicate a damselfish negative effect on transplants survival early on the study, which can change depending on the fish and coral species involved. Results also indicate a fish grazing positive effect, caused by the reduction of coral-algae competition pressure, mainly on P. astreoides. Parrotfishes seem to affect corals survival both negatively through direct biting, and positively by controlling algal growth. Overall, coral transplant success was almost unaffected by fish foraging activity although several

  6. Gross and microscopic pathology of hard and soft corals in New Caledonia.

    PubMed

    Work, Thierry M; Aeby, Greta S; Lasne, Gregory; Tribollet, Aline

    2014-07-01

    We surveyed the reefs of Grande Terre, New Caledonia, for coral diseases in 2010 and 2013. Lesions encountered in hard and soft corals were systematically described at the gross and microscopic level. We sampled paired and normal tissues from 101 and 65 colonies in 2010 and 2013, respectively, comprising 51 species of corals from 27 genera. Tissue loss was the most common gross lesion sampled (40%) followed by discoloration (28%), growth anomalies (13%), bleaching (10%), and flatworm infestation (1%). When grouped by gross lesions, the diversity of microscopic lesions as measured by Shannon-Wiener index was highest for tissue loss, followed by discoloration, bleaching, and growth anomaly. Our findings document an extension of the range of certain diseases such as Porites trematodiasis and endolithic hypermycosis (dark spots) to the Western Pacific as well as the presence of a putative cnidarian endosymbiont. We also expand the range of species infected by cell-associated microbial aggregates, and confirm the trend that these aggregates predominate in dominant genera of corals in the Indo-Pacific. This study highlights the importance of including histopathology as an integral component of baseline coral disease surveys, because a given gross lesion might be associated with multiple potential causative agents.

  7. The chemical cue tetrabromopyrrole from a biofilm bacterium induces settlement of multiple Caribbean corals

    PubMed Central

    Sneed, Jennifer M.; Sharp, Koty H.; Ritchie, Kimberly B.; Paul, Valerie J.

    2014-01-01

    Microbial biofilms induce larval settlement for some invertebrates, including corals; however, the chemical cues involved have rarely been identified. Here, we demonstrate the role of microbial biofilms in inducing larval settlement with the Caribbean coral Porites astreoides and report the first instance of a chemical cue isolated from a marine biofilm bacterium that induces complete settlement (attachment and metamorphosis) of Caribbean coral larvae. Larvae settled in response to natural biofilms, and the response was eliminated when biofilms were treated with antibiotics. A similar settlement response was elicited by monospecific biofilms of a single bacterial strain, Pseudoalteromonas sp. PS5, isolated from the surface biofilm of a crustose coralline alga. The activity of Pseudoalteromonas sp. PS5 was attributed to the production of a single compound, tetrabromopyrrole (TBP), which has been shown previously to induce metamorphosis without attachment in Pacific acroporid corals. In addition to inducing settlement of brooded larvae (P. astreoides), TBP also induced larval settlement for two broadcast-spawning species, Orbicella (formerly Montastraea) franksi and Acropora palmata, indicating that this compound may have widespread importance among Caribbean coral species. PMID:24850918

  8. Gross and microscopic pathology of hard and soft corals in New Caledonia

    USGS Publications Warehouse

    Work, Thierry M.; Aeby, Greta S.; Lasne, Gregory; Tribollet, Aline

    2014-01-01

    We surveyed the reefs of Grande Terre, New Caledonia, for coral diseases in 2010 and 2013. Lesions encountered in hard and soft corals were systematically described at the gross and microscopic level. We sampled paired and normal tissues from 101 and 65 colonies in 2010 and 2013, respectively, comprising 51 species of corals from 27 genera. Tissue loss was the most common gross lesion sampled (40%) followed by discoloration (28%), growth anomalies (13%), bleaching (10%), and flatworm infestation (1%). When grouped by gross lesions, the diversity of microscopic lesions as measured by Shannon–Wiener index was highest for tissue loss, followed by discoloration, bleaching, and growth anomaly. Our findings document an extension of the range of certain diseases such as Porites trematodiasis and endolithic hypermycosis (dark spots) to the Western Pacific as well as the presence of a putative cnidarian endosymbiont. We also expand the range of species infected by cell-associated microbial aggregates, and confirm the trend that these aggregates predominate in dominant genera of corals in the Indo-Pacific. This study highlights the importance of including histopathology as an integral component of baseline coral disease surveys, because a given gross lesion might be associated with multiple potential causative agents.

  9. [Community structure of zooxanthellate corals (Anthozoa: Scleractinia) in Carrizales coral reef, Pacific coast, Mexico].

    PubMed

    Reyes-Bonilla, Hector; Escobosa-González, Laura Elena; Cupul-Magaña, Amilcar L; Medina-Rosas, Pedro; Calderón-Aguilera, Luis E

    2013-06-01

    Coral reefs in the Mexican Pacific and notably those of the continental coastline of Colima state are still poorly studied. Fortunately, recent efforts have been carried out by researchers from different Mexican institutions to fill up these information gaps. The aim of this study was to determine the ecological structure of the rich and undisturbed coral building communities of Carrizales by using the point transect interception method (25m-long). For this, three survey expeditions were conducted between June and October 2005 and September 2006; and for comparison purposes, the reef was subdivided according to its position in the bay, and depth (0 to 5 m, and 6 to 10 m). Thirteen coral species were observed in the area, with Pocillopora verrucosa as the most abundant, contributing up to 32.8% of total cover, followed by Porites panamensis and Pocillopora capitata with 11% and 7%, respectively. Other species, Pocillopora damicornis, Pavona gigantea, Pocillopora eydouxi and Pocillopora inflata accounted for 1.5% to 2% of coral cover whereas the remaining five species had cover of less than 1%. Seven of the observed species represented new records for Colima state coastline: Pocillopora eydouxi, P inflata, P meandrina, Pavona duerdeni, P varians, Psammocora stellata and P contigua. This last species is a relevant record, because it has never been observed before in the Eastern Pacific. Although there was no significant difference (ANOVA, p = 0.478) neither in the abundance between the sides of the bay, nor between the depths considered, and the shallow zone observed the higher coral cover. Live coral cover was up to 61%, one of the highest ever reported for the Mexican Pacific, including the Gulf of California. The observed values of diversity (H' = 0.44 +/- 0.02), uniformity (J' = 0.76 +/- 0.02), and taxonomic distinctness index (delta* = 45.87 +/- 3.16), showed that currently this is the most important coral reef of Colima coastline. Currently, this region does not

  10. Diversity and Distribution of Symbiodinium Associated with Seven Common Coral Species in the Chagos Archipelago, Central Indian Ocean

    PubMed Central

    Obura, David; Sheppard, Charles R. C.; Visram, Shakil; Chen, Chaolun Allen

    2012-01-01

    The Chagos Archipelago designated as a no-take marine protected area in 2010, lying about 500 km south of the Maldives in the Indian Ocean, has a high conservation priority, particularly because of its fast recovery from the ocean-wide massive coral mortality following the 1998 coral bleaching event. The aims of this study were to examine Symbiodinium diversity and distribution associated with scleractinian corals in five atolls of the Chagos Archipelago, spread over 10,000 km 2. Symbiodinium clade diversity in 262 samples of seven common coral species, Acropora muricata, Isopora palifera, Pocillopora damicornis, P. verrucosa, P. eydouxi, Seriatopora hystrix, and Stylophora pistillata were determined using PCR-SSCP of the ribosomal internal transcribed spacer 1 (ITS1), PCR-DDGE of ITS2, and phylogenetic analyses. The results indicated that Symbiodinium in clade C were the dominant symbiont group in the seven coral species. Our analysis revealed types of Symbiodinium clade C specific to coral species. Types C1 and C3 (with C3z and C3i variants) were dominant in Acroporidae and C1 and C1c were the dominant types in Pocilloporidae. We also found 2 novel ITS2 types in S. hystrix and 1 novel ITS2 type of Symbiodinium in A. muricata. Some colonies of A. muricata and I. palifera were also associated with Symbiodinium A1. These results suggest that corals in the Chagos Archipelago host different assemblages of Symbiodinium types then their conspecifics from other locations in the Indian Ocean; and that future research will show whether these patterns in Symbiodinium genotypes may be due to local adaptation to specific conditions in the Chagos. PMID:22567113

  11. Assessing hidden species diversity in the coral Pocillopora damicornis from Eastern Australia

    NASA Astrophysics Data System (ADS)

    Schmidt-Roach, S.; Lundgren, P.; Miller, K. J.; Gerlach, G.; Noreen, A. M. E.; Andreakis, N.

    2013-03-01

    The incredible range of morphological plasticity present in scleractinian corals has confused the taxonomy of the group, prompting the introduction of "ecomorphs" to explain the observed correlation between local environmental conditions and phenotypic variation. Pocillopora damicornis (Linnaeus, 1758) represents one of the best known examples of eco-phenotypic variation in scleractinian corals with a variety of forms and reproductive strategies reported across its global distribution range. Here, we reconstruct genealogical relationships of P. damicornis colonies collected from thirteen locations along the East Australian coast to examine the relationship between genetic and phenotypic diversity in this species. Haplotype networks computed from two mitochondrial DNA regions (CR, ORF) indicate that the range of morphotypes observed within this taxon fall into at least five genetically distinct mitochondrial lineages. Nuclear (HSP70, ITS2) haplowebs on the other hand recover sharp genetic discontinuities among three of the morphological groups. We conclude that P. damicornis from Eastern Australia constitutes a cryptic species complex. The misinterpretation of taxonomical units within P. damicornis may well explain its perceived variation in the ecology, biology and life history across its range.

  12. A new species of monadal coral snake of the genus Micrurus (Serpentes, Elapidae) from western Amazon.

    PubMed

    Feitosa, Darlan Tavares; Da Silva, Nelson Jorge Jr; Pires, Matheus Godoy; Zaher, Hussam; Prudente, Ana Lúcia Da Costa

    2015-06-24

    We described a new species of monadal coral snake of the genus Micrurus from the region of Tabatinga and Leticia, along the boundaries of Brazil, Colombia, and Peru. The new species can be distinguished from the other congeners by the combination of the following characters: absence of a pale nuchal collar; black cephalic-cap extending from rostral to firstdorsal scale and enclosing white tipped prefrontal scales; upper half of first to four supralabials and postoculars black; tricolor body coloration, with 27-31 black rings bordered by narrower white rings and 27-31 red rings; tail coloration similar to body, with alternating black rings bordered by irregular narrow white rings, red rings of the same width as the black rings; ventral scales 205-225; subcaudal scales 39-47.

  13. Faunal breaks and species composition of Indo-Pacific corals: the role of plate tectonics, environment and habitat distribution.

    PubMed

    Keith, S A; Baird, A H; Hughes, T P; Madin, J S; Connolly, S R

    2013-07-22

    Species richness gradients are ubiquitous in nature, but the mechanisms that generate and maintain these patterns at macroecological scales remain unresolved. We use a new approach that focuses on overlapping geographical ranges of species to reveal that Indo-Pacific corals are assembled within 11 distinct faunal provinces. Province limits are characterized by co-occurrence of multiple species range boundaries. Unexpectedly, these faunal breaks are poorly predicted by contemporary environmental conditions and the present-day distribution of habitat. Instead, faunal breaks show striking concordance with geological features (tectonic plates and mantle plume tracks). The depth range over which a species occurs, its larval development rate and genus age are important determinants of the likelihood that species will straddle faunal breaks. Our findings indicate that historical processes, habitat heterogeneity and species colonization ability account for more of the present-day biogeographical patterns of corals than explanations based on the contemporary distribution of reefs or environmental conditions.

  14. Faunal breaks and species composition of Indo-Pacific corals: the role of plate tectonics, environment and habitat distribution

    PubMed Central

    Keith, S. A.; Baird, A. H.; Hughes, T. P.; Madin, J. S.; Connolly, S. R.

    2013-01-01

    Species richness gradients are ubiquitous in nature, but the mechanisms that generate and maintain these patterns at macroecological scales remain unresolved. We use a new approach that focuses on overlapping geographical ranges of species to reveal that Indo-Pacific corals are assembled within 11 distinct faunal provinces. Province limits are characterized by co-occurrence of multiple species range boundaries. Unexpectedly, these faunal breaks are poorly predicted by contemporary environmental conditions and the present-day distribution of habitat. Instead, faunal breaks show striking concordance with geological features (tectonic plates and mantle plume tracks). The depth range over which a species occurs, its larval development rate and genus age are important determinants of the likelihood that species will straddle faunal breaks. Our findings indicate that historical processes, habitat heterogeneity and species colonization ability account for more of the present-day biogeographical patterns of corals than explanations based on the contemporary distribution of reefs or environmental conditions. PMID:23698011

  15. Multi-species coral Sr/Ca based sea-surface temperature reconstruction data using Orbicella faveolata and Siderastrea siderea from Dry Tortugas National Park, Florida

    USGS Publications Warehouse

    Flannery, Jennifer A.; Richey, Julie N.; Thirumalai, Kaustubh; Poore, Richard Z.; Delong, Kristine

    2016-01-01

    New sub annual and mean annual Sr/Ca records from two species of massive coral, Orbicella faveolata (coral B3) and Siderastrea siderea (coral CG2), from the Dry Tortugas National Park, FL (DRTO). Both corals have well-constrained chronologies, with coral B3 ranging from 1893-2008 and coral CG2 ranging from 1837-2012. We combine these new records with published Sr/Ca data from three additional S. siderea coral colonies (DeLong et al., 2014) to generate a 278-year-long multi-species composite Sr/Ca-SST record from DRTO. This new record from a region sensitive to the Atlantic Multidecadal Oscillation (AMO) and Atlantic Meridional Overturning Circulation (AMOC) variations provides insight into the link between the two systems. Also included are new annual linear extension rates for each species. The coral samples and derived data were collected under the National Park Service Scientific Research and Collecting permits DRTO-2008-SCI-0015 and DRT0-2012-SCI-0001; accession numbers DRTO-241 and DRTO-353. For further information regarding data collection and/or processing methods refer to Flannery, J. A., J. N. Richey, K. Thirumalai, R. Z. Poore, and K. L. DeLong, 2016, Multi-species coral Sr/Ca based sea-surface temperature reconstruction using Orbicella faveolata and Siderastrea siderea from the Florida Straits, Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, http://dx.doi.org/10.1016/j.palaeo.2016.10.022.

  16. Plasticity of larval pre-competency in response to temperature: observations on multiple broadcast spawning coral species

    NASA Astrophysics Data System (ADS)

    Heyward, A. J.; Negri, A. P.

    2010-09-01

    The pre-competency period of coral larvae influences dispersal, and this may be affected under projected climate change conditions. In this laboratory study, we examined the influence of sea water temperature on the duration of pre-competency of larvae of four broadcast spawning coral species. Fungia repanda, Acropora millepora, A. spathulata and Symphyllia recta larvae demonstrated large differences in cohort competency levels when cultured over a 4°C range during the first 4 days post fertilisation. Warmer temperatures reduced pre-competency periods by at least a day for all species, but there were also indications of an upper temperature threshold of less than 32°C for the development of F. repanda, A. millepora and S. recta. These data suggest a general flexibility in ontogenic response to ambient water temperatures. Sea surface temperatures (SST) that differ at spawning time by as little as 2°C, due to inter-annual or latitudinal variation, are likely to alter coral larval dispersal ranges. In some locations, notably the central Indo-Pacific, where major coral spawning activity can coincide with seasonal SST maxima, a future 2°C increase due to climate change may have serious negative effects on coral development and distribution.

  17. Negative indirect effects of neighbors on imperiled scleractinian corals

    NASA Astrophysics Data System (ADS)

    Johnston, Lyza; Miller, M. W.

    2014-12-01

    Predation pressure on an individual may be influenced by spatial associations with other organisms. In the case of rare and imperiled species, such indirect interactions may affect the persistence and recovery of local populations. This study examined the effects of coral neighborhood composition on the foraging behavior and impact of the corallivorous gastropod, Coralliophila abbreviata. We conducted a manipulative field experiment in which focal colonies of the threatened scleractinian coral Acropora cervicornis had no neighbors, conspecific neighbors, alternative prey ( Orbicella faveolata) neighbors, or non-prey ( Porites asteroides) neighbors. Individually tagged C. abbreviata were then seeded into the study area and allowed to colonize the experimental plots. Initial colonization was significantly affected by the species of neighboring corals and snail abundance after colonization was negatively correlated with focal colony growth. Snails exhibited a strong prey preference for A. cervicornis over O. faveolata and responded numerically to neighborhood quality (i.e., relative preference for neighboring corals). Thus, conspecific neighbors had the greatest predator-mediated negative effect on focal colony performance followed by O. faveolata neighbors. The results suggest that C. abbreviata mediate apparent competition between O. faveolata and A. cervicornis as both species contributed to the local abundance of their shared predator. Additionally, home range estimates for tagged C. abbreviata were calculated, compared among sexes, and found to be significantly greater for males than for females. Overall, this study sheds light on the foraging behavior of an important coral predator and highlights the potential importance of consumer-mediated indirect interactions in the dynamics of severely reduced populations. The results also have direct implications for conservation and population enhancement efforts.

  18. Predator biomass, prey density, and species composition effects on group size in recruit coral reef fishes

    USGS Publications Warehouse

    DeMartini, Edward E.; Anderson, Todd W.; Friedlander, Alan M.; Beets, James P.

    2011-01-01

    Group incidence and size are described for recruit parrotfishes, wrasses, and damselfishes on Hawaiian reefs over 3 years (2006–2008) at sites spanning the archipelago (20–28°N, 155–177°W). Coral-poor and coral-rich areas were surveyed at sites with both low (Hawaii Island) and high (Midway Atoll) predator densities, facilitating examination of relations among predator and recruit densities, habitat, and group metrics. Predator and recruit densities varied spatially and temporally, with a sixfold range in total recruit densities among years. Group (≥2 recruits) metrics varied with time and tracked predator and recruit densities and the proportion of schooling species. Groups often included heterospecifics whose proportion increased with group size. A non-saturating relationship between group size and recruit density suggests that the anti-predator benefits of aggregation exceeded competitive costs. Grouping behavior may have overarching importance for recruit survival—even at high recruit densities—and merits further study on Hawaiian reefs and elsewhere.

  19. The microbiome of coral surface mucus has a key role in mediating holobiont health and survival upon disturbance

    PubMed Central

    Glasl, Bettina; Herndl, Gerhard J; Frade, Pedro R

    2016-01-01

    Microbes are well-recognized members of the coral holobiont. However, little is known about the short-term dynamics of mucus-associated microbial communities under natural conditions and after disturbances, and how these dynamics relate to the host's health. Here we examined the natural variability of prokaryotic communities (based on 16S ribosomal RNA gene amplicon sequencing) associating with the surface mucus layer (SML) of Porites astreoides, a species exhibiting cyclical mucus aging and shedding. Shifts in the prokaryotic community composition during mucus aging led to the prevalence of opportunistic and potentially pathogenic bacteria (Verrucomicrobiaceae and Vibrionaceae) in aged mucus and to a twofold increase in prokaryotic abundance. After the release of aged mucus sheets, the community reverted to its original state, dominated by Endozoicimonaceae and Oxalobacteraceae. Furthermore, we followed the fate of the coral holobiont upon depletion of its natural mucus microbiome through antibiotics treatment. After re-introduction to the reef, healthy-looking microbe-depleted corals started exhibiting clear signs of bleaching and necrosis. Recovery versus mortality of the P. astreoides holobiont was related to the degree of change in abundance distribution of the mucus microbiome. We conclude that the natural prokaryotic community inhabiting the coral SML contributes to coral health and that cyclical mucus shedding has a key role in coral microbiome dynamics. PMID:26953605

  20. Comparing Molecular Variation to Morphological Species Designations in the Deep-Sea Coral Narella Reveals New Insights into Seamount Coral Ranges

    PubMed Central

    Baco, Amy R.; Cairns, Stephen D.

    2012-01-01

    Recent studies have countered the paradigm of seamount isolation, confounding conservation efforts at a critical time. Efforts to study deep-sea corals, one of the dominant taxa on seamounts, to understand seamount connectivity, are hampered by a lack of taxonomic keys. A prerequisite for connectivity is species overlap. Attempts to better understand species overlap using DNA barcoding methods suggest coral species are widely distributed on seamounts and nearby features. However, no baseline has been established for variation in these genetic markers relative to morphological species designations for deep-sea octocoral families. Here we assess levels of genetic variation in potential octocoral mitochondrial barcode markers relative to thoroughly examined morphological species in the genus Narella. The combination of six markers used here, approximately 3350 bp of the mitochondrial genome, resolved 83% of the morphological species. Our results show that two of the markers, ND2 and NCR1, are not sufficient to resolve genera within Primnoidae, let alone species. Re-evaluation of previous studies of seamount octocorals based on these results suggest that those studies were looking at distributions at a level higher than species, possibly even genus or subfamily. Results for Narella show that using more markers provides haplotypes with relatively narrow depth ranges on the seamounts studied. Given the lack of 100% resolution of species with such a large portion of the mitochondrial genome, we argue that previous genetic studies have not resolved the degree of species overlap on seamounts and that we may not have the power to even test the hypothesis of seamount isolation using mitochondrial markers, let alone refute it. Thus a precautionary approach is advocated in seamount conservation and management, and the potential for depth structuring should be considered. PMID:23029093

  1. Comparing molecular variation to morphological species designations in the deep-sea coral Narella reveals new insights into seamount coral ranges.

    PubMed

    Baco, Amy R; Cairns, Stephen D

    2012-01-01

    Recent studies have countered the paradigm of seamount isolation, confounding conservation efforts at a critical time. Efforts to study deep-sea corals, one of the dominant taxa on seamounts, to understand seamount connectivity, are hampered by a lack of taxonomic keys. A prerequisite for connectivity is species overlap. Attempts to better understand species overlap using DNA barcoding methods suggest coral species are widely distributed on seamounts and nearby features. However, no baseline has been established for variation in these genetic markers relative to morphological species designations for deep-sea octocoral families. Here we assess levels of genetic variation in potential octocoral mitochondrial barcode markers relative to thoroughly examined morphological species in the genus Narella. The combination of six markers used here, approximately 3350 bp of the mitochondrial genome, resolved 83% of the morphological species. Our results show that two of the markers, ND2 and NCR1, are not sufficient to resolve genera within Primnoidae, let alone species. Re-evaluation of previous studies of seamount octocorals based on these results suggest that those studies were looking at distributions at a level higher than species, possibly even genus or subfamily. Results for Narella show that using more markers provides haplotypes with relatively narrow depth ranges on the seamounts studied. Given the lack of 100% resolution of species with such a large portion of the mitochondrial genome, we argue that previous genetic studies have not resolved the degree of species overlap on seamounts and that we may not have the power to even test the hypothesis of seamount isolation using mitochondrial markers, let alone refute it. Thus a precautionary approach is advocated in seamount conservation and management, and the potential for depth structuring should be considered.

  2. Variation in the size structure of corals is related to environmental extremes in the Persian Gulf.

    PubMed

    Bauman, Andrew G; Pratchett, Morgan S; Baird, Andrew H; Riegl, Bernhard; Heron, Scott F; Feary, David A

    2013-03-01

    The size structure of coral populations is the culmination of key demographic events, including recruitment, mortality and growth, thereby providing important insights to recent ecological dynamics. Importantly, the size structure of corals reflects both intrinsic (inherent life-history characteristics) and extrinsic (enhanced mortality due to chronic or acute disturbances) forcing on local populations, enabling post-hoc assessment of spatial and taxonomic differences in susceptibility to disturbance. This study examined the size structure of four locally abundant corals (Acropora downingi, Favia pallida, Platygyra daedalea, and massive Porites spp.) in two regions of the Persian Gulf: the southern Gulf (Dubai and Abu Dhabi) and eastern Gulf (western Musandam). Significant and consistent differences were apparent in mean colony sizes and size-distributions between regions. All corals in the southern Gulf were significantly smaller, and their size structure positively skewed and relatively more leptokurtic (i.e., peaky) compared to corals in the eastern Gulf. Sea surface temperatures, salinity, and the recent frequency of mass bleaching are all higher, in the southern Gulf, suggesting higher mortality rates and/or slower growth in these populations. Differences in size structure between locations were more pronounced than differences between species at each location, suggesting that extreme differences in environmental conditions and disturbance events have a greater influence on population dynamics in the Gulf than inherent differences in their life-history characteristics.

  3. 88Sr/86Sr fractionation in inorganic aragonite and in corals

    NASA Astrophysics Data System (ADS)

    Fruchter, Noa; Eisenhauer, Anton; Dietzel, Martin; Fietzke, Jan; Böhm, Florian; Montagna, Paolo; Stein, Moti; Lazar, Boaz; Rodolfo-Metalpa, Riccardo; Erez, Jonathan

    2016-04-01

    Conflicting results have been reported for the stable Sr isotope fractionation, specifically with respect to the influence of temperature. In an experimental study we have investigated the stable Sr isotope systematics for inorganically precipitated and biogenic (coral) aragonite (natural and laboratory-cultured). Inorganic aragonite precipitation experiments were performed from natural seawater using the CO2 diffusion technique. The experiments were performed at different temperatures and different carbonate ion concentrations. 88Sr/86Sr of the inorganic aragonite precipitated in the experiments are 0.2‰ lighter than seawater, but showed no correlation to the water temperature or to CO32- concentration. Similar observations are made in different coral species (Cladocora caespitosa, Porites sp. and Acropora sp.), with identical fractionation from the bulk solution and no correlation to temperature or CO32- concentration. The lack of 88Sr/86Sr variability in corals at different environmental parameters and the similarity to the 88Sr/86Sr fractionation in inorganic aragonite may indicate a similar Sr incorporation mechanism in corals skeleton and inorganic aragonite, and therefore the previously proposed Rayleigh-based multi element model (Gaetani et al., 2011) cannot explain the process of Sr incorporation in the coral skeletal material. It is proposed that the relatively constant 88Sr/86Sr fractionation in aragonite can be used for paleo reconstruction of seawater 88Sr/86Sr composition. The seawater 88Sr/86Sr ratio reconstruction can be further used in calcite samples to reconstruct paleo precipitation rates.

  4. Site-specific variation in gene expression from Symbiodinium spp. associated with offshore and inshore Porites astreoides in the lower Florida Keys is lost with bleaching and disease stress.

    PubMed

    Salas, Briana Hauff; Haslun, Joshua A; Strychar, Kevin B; Ostrom, Peggy H; Cervino, James M

    2017-01-01

    Scleractinian coral are experiencing unprecedented rates of mortality due to increases in sea surface temperatures in response to global climate change. Some coral species however, survive high temperature events due to a reduced susceptibility to bleaching. We investigated the relationship between bleaching susceptibility and expression of five metabolically related genes of Symbiodinium spp. from the coral Porites astreoides originating from an inshore and offshore reef in the Florida Keys. The acclimatization potential of Symbiodinium spp. to changing temperature regimes was also measured via a two-year reciprocal transplant between the sites. Offshore coral fragments displayed significantly higher expression in Symbiodinium spp. genes PCNA, SCP2, G3PDH, PCP and psaE than their inshore counterparts (p<0.05), a pattern consistent with increased bleaching susceptibility in offshore corals. Additionally, gene expression patterns in Symbiodinium spp. from site of origin were conserved throughout the two-year reciprocal transplant, indicating acclimatization did not occur within this multi-season time frame. Further, laboratory experiments were used to investigate the influence of acute high temperature (32°C for eight hours) and disease (lipopolysaccharide of Serratia marcescens) on the five metabolically related symbiont genes from the same offshore and inshore P. astreoides fragments. Gene expression did not differ between reef fragments, or as a consequence of acute exposure to heat or heat and disease, contrasting to results found in the field. Gene expression reported here indicates functional variation in populations of Symbiodinium spp. associated with P. astreoides in the Florida Keys, and is likely a result of localized adaptation. However, gene expression patterns observed in the lab imply that functional variation in zooxanthellae observed under conditions of chronic moderate stress is lost under the acute extreme conditions studied here.

  5. Site-specific variation in gene expression from Symbiodinium spp. associated with offshore and inshore Porites astreoides in the lower Florida Keys is lost with bleaching and disease stress

    PubMed Central

    Haslun, Joshua A.; Strychar, Kevin B.; Ostrom, Peggy H.; Cervino, James M.

    2017-01-01

    Scleractinian coral are experiencing unprecedented rates of mortality due to increases in sea surface temperatures in response to global climate change. Some coral species however, survive high temperature events due to a reduced susceptibility to bleaching. We investigated the relationship between bleaching susceptibility and expression of five metabolically related genes of Symbiodinium spp. from the coral Porites astreoides originating from an inshore and offshore reef in the Florida Keys. The acclimatization potential of Symbiodinium spp. to changing temperature regimes was also measured via a two-year reciprocal transplant between the sites. Offshore coral fragments displayed significantly higher expression in Symbiodinium spp. genes PCNA, SCP2, G3PDH, PCP and psaE than their inshore counterparts (p<0.05), a pattern consistent with increased bleaching susceptibility in offshore corals. Additionally, gene expression patterns in Symbiodinium spp. from site of origin were conserved throughout the two-year reciprocal transplant, indicating acclimatization did not occur within this multi-season time frame. Further, laboratory experiments were used to investigate the influence of acute high temperature (32°C for eight hours) and disease (lipopolysaccharide of Serratia marcescens) on the five metabolically related symbiont genes from the same offshore and inshore P. astreoides fragments. Gene expression did not differ between reef fragments, or as a consequence of acute exposure to heat or heat and disease, contrasting to results found in the field. Gene expression reported here indicates functional variation in populations of Symbiodinium spp. associated with P. astreoides in the Florida Keys, and is likely a result of localized adaptation. However, gene expression patterns observed in the lab imply that functional variation in zooxanthellae observed under conditions of chronic moderate stress is lost under the acute extreme conditions studied here. PMID:28355291

  6. Identification of Scleractinian Coral Recruits Using Fluorescent Censusing and DNA Barcoding Techniques

    PubMed Central

    Hsu, Chia-Min; de Palmas, Stéphane; Kuo, Chao-Yang; Denis, Vianney; Chen, Chaolun Allen

    2014-01-01

    The identification of coral recruits has been problematic due to a lack of definitive morphological characters being available for higher taxonomic resolution. In this study, we tested whether fluorescent detection of coral recruits used in combinations of different DNA-barcoding markers (cytochrome oxidase I gene [COI], open reading frame [ORF], and nuclear Pax-C intron [PaxC]) could be useful for increasing the resolution of coral spat identification in ecological studies. One hundred and fifty settlement plates were emplaced at nine sites on the fringing reefs of Kenting National Park in southern Taiwan between April 2011 and September 2012. A total of 248 living coral spats and juveniles (with basal areas ranging from 0.21 to 134.57 mm2) were detected on the plates with the aid of fluorescent light and collected for molecular analyses. Using the COI DNA barcoding technique, 90.3% (224/248) of coral spats were successfully identified into six genera, including Acropora, Isopora, Montipora, Pocillopora, Porites, and Pavona. PaxC further separated I. cuneata and I. palifera of Isopora from Acropora, and ORF successfully identified the species of Pocillopora (except P. meandrina and P. eydouxi). Moreover, other cnidarian species such as actinarians, zoanthids, and Millepora species were visually found using fluorescence and identified by COI DNA barcoding. This combination of existing approaches greatly improved the taxonomic resolution of early coral life stages, which to date has been mainly limited to the family level based on skeletal identification. Overall, this study suggests important improvements for the identification of coral recruits in ecological studies. PMID:25211345

  7. Pigmentation of massive corals as a simple bioindicator for marine water quality.

    PubMed

    Cooper, Timothy F; Fabricius, Katharina E

    2012-01-01

    Photo-acclimatisation by the algal endosymbionts of scleractinian corals to changes in environmental conditions may influence their density and/or the concentration of photosynthetic pigments, and hence coral brightness, on short time-scales. To examine coral pigmentation as a bioindicator of water quality, the brightness of massive corals was quantified using colour charts, concentrations of the pigment chlorophyll a and reflectance spectrometry in the field and with manipulative experiments. Along a water quality gradient, massive Porites became progressively lighter as nutrients decreased and irradiance increased. A laboratory experiment showed that Porites nubbins darkened within 25 days following exposure to reduced water quality. The results of a transplantation experiment of Porites nubbins in a manipulation incorporating multiple depths and zones of water quality confirmed colony brightness as a simple tool to monitor changes in marine water quality, provided effects due to other influences on pigmentation, e.g. seawater temperatures, are taken into consideration.

  8. Li/Mg systematics in scleractinian corals: Calibration of the thermometer

    NASA Astrophysics Data System (ADS)

    Montagna, Paolo; McCulloch, Malcolm; Douville, Eric; López Correa, Matthias; Trotter, Julie; Rodolfo-Metalpa, Riccardo; Dissard, Delphine; Ferrier-Pagès, Christine; Frank, Norbert; Freiwald, André; Goldstein, Steve; Mazzoli, Claudio; Reynaud, Stephanie; Rüggeberg, Andres; Russo, Simone; Taviani, Marco

    2014-05-01

    We show that the Li/Mg systematics of a large suite of aragonitic coral skeletons, representing a wide range of species inhabiting disparate environments, provides a robust proxy for ambient seawater temperature. The corals encompass both zooxanthellate and azooxanthellate species (Acropora sp., Porites sp., Cladocora caespitosa, Lophelia pertusa, Madrepora oculata and Flabellum impensum) collected from shallow, intermediate, and deep-water habitats, as well as specimens cultured in tanks under temperature-controlled conditions. The Li/Mg ratios observed in corals from these diverse tropical, temperate, and deep-water environments are shown to be highly correlated with temperature, giving an exponential temperature relationship of: Li/Mg (mmol/mol) = 5.41 exp (-0.049 * T) (r2 = 0.975, n = 49). Based on the standard error of the Li/Mg versus temperature correlation, we obtain a typical precision of ±0.9 °C for the wide range of species analysed, similar or better than that of other less robust coral temperature proxies such as Sr/Ca ratios.

  9. The IUCN Red List of Threatened Species: an assessment of coral reef fishes in the US Pacific Islands

    NASA Astrophysics Data System (ADS)

    Zgliczynski, B. J.; Williams, I. D.; Schroeder, R. E.; Nadon, M. O.; Richards, B. L.; Sandin, S. A.

    2013-09-01

    Widespread declines among many coral reef fisheries have led scientists and managers to become increasingly concerned over the extinction risk facing some species. To aid in assessing the extinction risks facing coral reef fishes, large-scale censuses of the abundance and distribution of individual species are critically important. We use fisheries-independent data collected as part of the NOAA Pacific Reef Assessment and Monitoring Program from 2000 to 2009 to describe the range and density across the US Pacific of coral reef fishes included on The International Union for the Conservation of Nature's (IUCN) 2011 Red List of Threatened Species. Forty-five species, including sharks, rays, groupers, humphead wrasse ( Cheilinus undulatus), and bumphead parrotfish ( Bolbometopon muricatum), included on the IUCN List, were recorded in the US Pacific Islands. Most species were generally rare in the US Pacific with the exception of a few species, principally small groupers and reef sharks. The greatest diversity and densities of IUCN-listed fishes were recorded at remote and uninhabited islands of the Pacific Remote Island Areas; in general, lower densities were observed at reefs of inhabited islands. Our findings complement IUCN assessment efforts, emphasize the efficacy of large-scale assessment and monitoring efforts in providing quantitative data on reef fish assemblages, and highlight the importance of protecting populations at remote and uninhabited islands where some species included on the IUCN Red List of Threatened Species can be observed in abundance.

  10. Identifying the world's most climate change vulnerable species: a systematic trait-based assessment of all birds, amphibians and corals.

    PubMed

    Foden, Wendy B; Butchart, Stuart H M; Stuart, Simon N; Vié, Jean-Christophe; Akçakaya, H Resit; Angulo, Ariadne; DeVantier, Lyndon M; Gutsche, Alexander; Turak, Emre; Cao, Long; Donner, Simon D; Katariya, Vineet; Bernard, Rodolphe; Holland, Robert A; Hughes, Adrian F; O'Hanlon, Susannah E; Garnett, Stephen T; Sekercioğlu, Cagan H; Mace, Georgina M

    2013-01-01

    Climate change will have far-reaching impacts on biodiversity, including increasing extinction rates. Current approaches to quantifying such impacts focus on measuring exposure to climatic change and largely ignore the biological differences between species that may significantly increase or reduce their vulnerability. To address this, we present a framework for assessing three dimensions of climate change vulnerability, namely sensitivity, exposure and adaptive capacity; this draws on species' biological traits and their modeled exposure to projected climatic changes. In the largest such assessment to date, we applied this approach to each of the world's birds, amphibians and corals (16,857 species). The resulting assessments identify the species with greatest relative vulnerability to climate change and the geographic areas in which they are concentrated, including the Amazon basin for amphibians and birds, and the central Indo-west Pacific (Coral Triangle) for corals. We found that high concentration areas for species with traits conferring highest sensitivity and lowest adaptive capacity differ from those of highly exposed species, and we identify areas where exposure-based assessments alone may over or under-estimate climate change impacts. We found that 608-851 bird (6-9%), 670-933 amphibian (11-15%), and 47-73 coral species (6-9%) are both highly climate change vulnerable and already threatened with extinction on the IUCN Red List. The remaining highly climate change vulnerable species represent new priorities for conservation. Fewer species are highly climate change vulnerable under lower IPCC SRES emissions scenarios, indicating that reducing greenhouse emissions will reduce climate change driven extinctions. Our study answers the growing call for a more biologically and ecologically inclusive approach to assessing climate change vulnerability. By facilitating independent assessment of the three dimensions of climate change vulnerability, our approach can

  11. Discerning the timing and cause of historical mortality events in modern Porites from the Great Barrier Reef

    NASA Astrophysics Data System (ADS)

    Clark, Tara R.; Zhao, Jian-xin; Roff, George; Feng, Yue-xing; Done, Terence J.; Nothdurft, Luke D.; Pandolfi, John M.

    2014-08-01

    The life history strategies of massive Porites corals make them a valuable resource not only as key providers of reef structure, but also as recorders of past environmental change. Yet recent documented evidence of an unprecedented increase in the frequency of mortality in Porites warrants investigation into the history of mortality and associated drivers. To achieve this, both an accurate chronology and an understanding of the life history strategies of Porites are necessary. Sixty-two individual Uranium-Thorium (U-Th) dates from 50 dead massive Porites colonies from the central inshore region of the Great Barrier Reef (GBR) revealed the timing of mortality to have occurred predominantly over two main periods from 1989.2 ± 4.1 to 2001.4 ± 4.1, and from 2006.4 ± 1.8 to 2008.4 ± 2.2 A.D., with a small number of colonies dating earlier. Overall, the peak ages of mortality are significantly correlated with maximum sea-surface temperature anomalies. Despite potential sampling bias, the frequency of mortality increased dramatically post-1980. These observations are similar to the results reported for the Southern South China Sea. High resolution measurements of Sr/Ca and Mg/Ca obtained from a well preserved sample that died in 1994.6 ± 2.3 revealed that the time of death occurred at the peak of sea surface temperatures (SST) during the austral summer. In contrast, Sr/Ca and Mg/Ca analysis in two colonies dated to 2006.9 ± 3.0 and 2008.3 ± 2.0, suggest that both died after the austral winter. An increase in Sr/Ca ratios and the presence of low Mg-calcite cements (as determined by SEM and elemental ratio analysis) in one of the colonies was attributed to stressful conditions that may have persisted for some time prior to mortality. For both colonies, however, the timing of mortality coincides with the 4th and 6th largest flood events reported for the Burdekin River in the past 60 years, implying that factors associated with terrestrial runoff may have been

  12. [Taxonomy and distribution of the hermatypic corals (Scleractinia) of the Revillagigedo Archipelago, Mexico].

    PubMed

    Ketchum, J T; Reyes Bonilla, H

    2001-01-01

    In spite of some recent detailed accounts about the scleractinian corals of the Archipiélago de Revillagigedo, taxonomic work on this fauna has been sparse. Consequently, solid taxonomic background is needed, especially to support further studies at community level. During five field trips (between 1990 and 1995) collections were made at different depths on three of the archipelago islands: Socorro, Clarión and San Benedicto. A total of 250 specimens were collected. Coral identifications were made using co-occurrence methods concomitant with their descriptions, diagnosis and illustrations from a number of publications, and with morphological analysis. Coral distributions were taken from literature. Twenty-two species of zooxanthellate scleractinian corals are described, with their local and world-wide geographic distribution, and each illustrated with macro and microphotographs. Keys to the genera and species of the archipelago are also included. Porites and Pocillopora exhibit the highest species richness with a great intraspecific variation, as well as a number of morphological convergences within and between species which form species complexes, and several new species and morphs. Clarion, the oldest and most isolated island of the archipelago, harbors a number of coral morphs that are probable new species. More than half of the species found at the Revillagigedos are distributed exclusively on oceanic islands of the eastern Pacific and close to one third exist only at this archipelago. The Revillagigedos have strong faunal similarities and share a number of endemics with Clipperton Atoll, all of which support the idea that these islands constitute a separate biogeographic subregion within the eastern Pacific. Lastly, the present document substantiates the hypothesis that the Revillagigedos are important stepping-stone islands for the migration of in-shore marine species from the Central to the eastern Pacific.

  13. Identifying the World's Most Climate Change Vulnerable Species: A Systematic Trait-Based Assessment of all Birds, Amphibians and Corals

    PubMed Central

    Foden, Wendy B.; Butchart, Stuart H. M.; Stuart, Simon N.; Vié, Jean-Christophe; Akçakaya, H. Resit; Angulo, Ariadne; DeVantier, Lyndon M.; Gutsche, Alexander; Turak, Emre; Cao, Long; Donner, Simon D.; Katariya, Vineet; Bernard, Rodolphe; Holland, Robert A.; Hughes, Adrian F.; O’Hanlon, Susannah E.; Garnett, Stephen T.; Şekercioğlu, Çagan H.; Mace, Georgina M.

    2013-01-01

    Climate change will have far-reaching impacts on biodiversity, including increasing extinction rates. Current approaches to quantifying such impacts focus on measuring exposure to climatic change and largely ignore the biological differences between species that may significantly increase or reduce their vulnerability. To address this, we present a framework for assessing three dimensions of climate change vulnerability, namely sensitivity, exposure and adaptive capacity; this draws on species’ biological traits and their modeled exposure to projected climatic changes. In the largest such assessment to date, we applied this approach to each of the world’s birds, amphibians and corals (16,857 species). The resulting assessments identify the species with greatest relative vulnerability to climate change and the geographic areas in which they are concentrated, including the Amazon basin for amphibians and birds, and the central Indo-west Pacific (Coral Triangle) for corals. We found that high concentration areas for species with traits conferring highest sensitivity and lowest adaptive capacity differ from those of highly exposed species, and we identify areas where exposure-based assessments alone may over or under-estimate climate change impacts. We found that 608–851 bird (6–9%), 670–933 amphibian (11–15%), and 47–73 coral species (6–9%) are both highly climate change vulnerable and already threatened with extinction on the IUCN Red List. The remaining highly climate change vulnerable species represent new priorities for conservation. Fewer species are highly climate change vulnerable under lower IPCC SRES emissions scenarios, indicating that reducing greenhouse emissions will reduce climate change driven extinctions. Our study answers the growing call for a more biologically and ecologically inclusive approach to assessing climate change vulnerability. By facilitating independent assessment of the three dimensions of climate change vulnerability

  14. A new species of Nebalia (Crustacea, Leptostraca) from coral reefs at Pulau Payar, Malaysia

    PubMed Central

    Othman, B.H.R.; Toda, T.; Kikuchi, T.

    2016-01-01

    Abstract A new species of Leptostraca, Nebalia terazakii sp. n. is described and figured. The species was sampled from the coral reefs of Pulau Payar Marine Park, Langkawi, Malaysia. There are 32 existing species of Nebalia but Nebalia terazakii sp. n. can be distinguished from the other known species of Nebalia by the following combination of characters: the rostrum is 1.89 times as long as wide and the eyes have no dorsal papilla or lobes. Article 4 of the antennular peduncle has one short thick distal spine. The proximal article of the endopod of maxilla 2 is shorter than the distal, a feature peculiar to Nebalia terazakii sp. n., the exopod of maxilla 2 is longer than article 1 of the endopod, the posterior dorsal borders of the pleonites 6 to 7 are provided with distally sharp denticles, anal plate with prominent lateral shoulder and finally, the terminal seta of the caudal rami is 1.17 times the length of the entire rami. PMID:27551211

  15. Dietary partitioning by five sympatric species of stingray (Dasyatidae) on coral reefs.

    PubMed

    O'Shea, O R; Thums, M; van Keulen, M; Kempster, R M; Meekan, M G

    2013-06-01

    Dietary characteristics and the degree of dietary partitioning by five species of sympatric stingray were assessed using stomach content and sediment analyses within a coral reef lagoon at Ningaloo Reef, Western Australia (the cowtail Pastinachus atrus, blue-spotted fantail Taeniura lymma, blue-spotted mask Neotrygon kuhlii, porcupine Urogymnus asperrimus rays and the reticulate whipray Himantura uarnak). A total of 2804 items were recovered from the stomachs of 170 rays and 3215 individual taxa from the environment, which were used in selectivity analyses. Twenty-four prey taxa were identified from stomach contents and pooled into 10 taxonomic categories for analysis, of which annelids, prawns, brachyurans and bivalves were the most abundant, together accounting for 96% of the diet. Himantura uarnak had the greatest interspecific dissimilarity in diet, consuming a larger proportion of crustaceans, notably penaeids (41% of total diet) than the other four species of rays, all of which had diets dominated by annelids (71-82% of total diet). Crustacean specialization by H. uarnak may exist to maximize resources and reduce competition among sympatric species. The remaining species may partition resources on the basis of space, rather than diet.

  16. Contrasting evolutionary patterns in two reef-corals and their possible relationship to life history traits

    SciTech Connect

    Foster, A.B.

    1985-01-01

    Multivariate statistical analyses have been used to redefine species within two genera of reef-corals (Porites and Montastraea) and to trace their evolutionary patterns through a continuous sequence from late Miocene to early Pliocene time. The material studied consists of populations sampled at regular intervals through four stratigraphic sections in the northern Dominican Republic. The results show that species in the first genus (Porites) have relatively short durations, morphologic stability, and narrow spatial distributions. Their overall evolutionary history is characterized by short periods of radiation and widespread extinction, separated by longer periods of stasis. In contrast, species in the second genus (Montastraea) exhibit various different durations and distributions and directional morphologic trends. These differences in patterns may be related to the dissimilar life histories of the two genera. Patterns in the first genus appear more common in organisms having high larval recruitment, high mortality, high genetic variation, and less morphologic distance between species. Patterns in the second genus occur more frequently in slower growing, phenotypically plastic organisms experiencing less recruitment and mortality and showing more morphologic distance between species.

  17. Physiological and isotopic responses of scleractinian corals to ocean acidification

    NASA Astrophysics Data System (ADS)

    Krief, Shani; Hendy, Erica J.; Fine, Maoz; Yam, Ruth; Meibom, Anders; Foster, Gavin L.; Shemesh, Aldo

    2010-09-01

    Uptake of anthropogenic CO 2 by the oceans is altering seawater chemistry with potentially serious consequences for coral reef ecosystems due to the reduction of seawater pH and aragonite saturation state ( Ωarag). The objectives of this long-term study were to investigate the viability of two ecologically important reef-building coral species, massive Porites sp. and Stylophora pistillata, exposed to high pCO 2 (or low pH) conditions and to observe possible changes in physiologically related parameters as well as skeletal isotopic composition. Fragments of Porites sp. and S. pistillata were kept for 6-14 months under controlled aquarium conditions characterized by normal and elevated pCO 2 conditions, corresponding to pH T values of 8.09, 7.49, and 7.19, respectively. In contrast with shorter, and therefore more transient experiments, the long experimental timescale achieved in this study ensures complete equilibration and steady state with the experimental environment and guarantees that the data provide insights into viable and stably growing corals. During the experiments, all coral fragments survived and added new skeleton, even at seawater Ωarag < 1, implying that the coral skeleton is formed by mechanisms under strong biological control. Measurements of boron (B), carbon (C), and oxygen (O) isotopic composition of skeleton, C isotopic composition of coral tissue and symbiont zooxanthellae, along with physiological data (such as skeletal growth, tissue biomass, zooxanthellae cell density, and chlorophyll concentration) allow for a direct comparison with corals living under normal conditions and sampled simultaneously. Skeletal growth and zooxanthellae density were found to decrease, whereas coral tissue biomass (measured as protein concentration) and zooxanthellae chlorophyll concentrations increased under high pCO 2 (low pH) conditions. Both species showed similar trends of δ 11B depletion and δ 18O enrichment under reduced pH, whereas the δ 13C results

  18. A new species of antipatharian coral (Cnidaria: Anthozoa: Antipatharia: Schizopathidae) from the Pacific coast of Costa Rica

    SciTech Connect

    Opresko, Dennis M; Breedy, Odalisca

    2010-09-01

    A new species of black coral, Aphanipathes colombiana (Cnidaria:Antipatharia) from the Caribbean coast of Colombia is described. The species forms small flabellate colonies with anisomorphic polypar spines. It is morphologically similar to the western Atlantic species A. thyoides (Pourtales) but its hypostomal polypar spines are not reduced in size. The new species also resembles the Indo-Pacific species A. reticulata van Pesch but it has smooth-surfaced polypar spines, whereas in A. reticulata these spines have small tubercles on their surface

  19. Species boundaries and phylogenetic relationships between Atlanto-Mediterranean shallow-water and deep-sea coral associated Hexadella species (Porifera, Ianthellidae).

    PubMed

    Reveillaud, Julie; Remerie, Thomas; van Soest, Rob; Erpenbeck, Dirk; Cárdenas, Paco; Derycke, Sofie; Xavier, Joana R; Rigaux, Annelien; Vanreusel, Ann

    2010-07-01

    Coral reefs constitute the most diverse ecosystem of the marine realm and an increasing number of studies are focusing on coral species boundaries, distribution, and on processes that control species ranges. However, less attention has been paid to coral associated species. Deep-sea sponges dominate cold-water coral ecosystems, but virtually nothing is known about their molecular diversity. Moreover, species boundaries based on morphology may sometimes be inadequate, since sponges have few diagnostic characters. In this study, we investigated the molecular diversity within the genus Hexadella (Porifera, Demospongiae, Verongida, Ianthellidae) from the European shallow-water environment to the deep-sea coral ecosystems. Three molecular markers were used: one mitochondrial (COI) and two nuclear gene fragments (28S rDNA and the ATPS intron). Phylogenetic analyses revealed deeply divergent deep-sea clades congruent across the mitochondrial and nuclear markers. One clade contained specimens from the Irish, the Scottish, and the Norwegian margins and the Greenland Sea (Hexadella dedritifera) while another clade contained specimens from the Ionian Sea, the Bay of Biscay, and the Irish margin (H. cf. dedritifera). Moreover, these deeply divergent deep-sea clades showed a wide distribution suggesting a connection between the reefs. The results also point to the existence of a new deep-sea species (Hexadella sp.) in the Mediterranean Sea and of a cryptic shallow-water species (Hexadella cf. pruvoti) in the Gorringe Bank. In contrast, low genetic differentiation between H. cf. dedritifera and H. pruvoti from the Mediterranean Sea was observed. All Hexadella racovitzai specimens from the Mediterranean Sea (shallow and deep) to the Atlantic formed a monophyletic group.

  20. Abundance, composition and growth rate of coral recruits on dead corals following the 2010 bleaching event at Mu Ko Surin, the Andaman Sea

    NASA Astrophysics Data System (ADS)

    Yucharoen, Mathinee; Yeemin, Thamasak; Casareto, Beatriz E.; Suzuki, Yoshimi; Samsuvan, Watchara; Sangmanee, Kanwara; Klinthong, Wanlaya; Pengsakun, Sittiporn; Sutthacheep, Makamas

    2015-06-01

    Elevated seawater temperatures in the summer months of 2010 were associated with widespread coral mortality in Thailand. A large number of corals at Mu Ko Surin died following the bleaching event. Understanding of the recruitment of corals would improve our ability to predict the potential for coral recovery from the impacts of bleaching events, as well as the interpretation of spatio-temporal variability in coral community structure. This study aims to examine the composition, abundance and growth rate of juvenile corals and the potential of reef recovery at Mu Ko Surin in order to help to understand how reefs react to major disturbances. We found that the densities of coral recruits varied among years and study sites. In the year 2011, coral recruitments ranged between 0.18 ± 0.02 to 1.67 ± 0.07 recruits per m2 for 10 study sites. While in 2012, the monitoring revealed a range between 0.96 ± 0.16 and 2.19 ± 0.21 recruits per m2 from 5 study sites. Fungia, Acropora, Porites and Favites were the dominant groups of coral recruits. In terms substrate forms, they were significant differences between sampling years but the preferential dominant substrate forms did not differ. The Acropora recruits at Ko Torinla showed normal distributions of size class during the two periods. Their ranges in 2011 and 2012 were 4-30 and 13-54 mm, respectively. Six species of Acropora recruits, i.e. Acropora intermedia, A. nasuta, A. cerealis, A. subulata, A. muricata and A. latistella were found. They showed diverse growth rates due to the spatial distribution of 2.11 ± 0.59 to 7.47 ± 1.37 cm per year. This study provides useful data in terms of coral recruitment and recovery from degradation and disturbance, especially from temperature changes induced by coral bleaching. The findings suggest that there is the possibility for coral recovery around Mu Ko Surin following the 2010 bleaching event.

  1. Field Calibration of the δ11B-pH Proxy in Corals and Calcified Algae at a Shallow Hydrothermal Vent and Adjacent Coral Reef

    NASA Astrophysics Data System (ADS)

    Day, R. D.; Christopher, S. J.; Young, C.; Brainard, R. E.; Butterfield, D. A.; Stewart, J.

    2015-12-01

    There is increasing interest in using the boron isotopic composition (δ11B) of biogenic carbonates as a proxy for seawater pH to better understand recent ocean acidification. The utility of this proxy hinges on the production of robust species-specific δ11B-pH calibrations; yet, challenges remain in the interpretation of boron isotope data due to biases introduced by physiological, environmental, and analytical factors. The shallow hydrothermal vents in the Maug Islands caldera (Marianas Islands) and the adjacent coral reefs exhibit a localized gradient > 1 pH unit. This gradient was used as a natural laboratory to assess the efficacy of using skeletal δ11B in a variety of corals (Porites spp., Pocillipora spp., Acropora spp.) and calcified algae (Halimeda spp. and Corallinales) as biosensors of seawater pH. Three sites were selected representing oceanic background, intermediate, and low pH zones, and direct seawater pH measurements were recorded for 3 months using SeaFETs. Corals and algae growing naturally in situ were collected from these 3 sites. In addition, corals and algae collected from a background location were stained and transplanted to these sites and allowed to grow for 3 months. Measurements of δ11B in skeletal material made by multi-collector inductively coupled mass spectrometry are compared to direct seawater pH measurements to assess the sensitivity and robustness of the δ11B proxy in these candidate biosensors in predicting ambient pH in the field. These data will inform ongoing efforts by the Archive of Coral Ecosystem Specimens (ACES) to collect marine carbonates for analysis and archival in the Marine Environmental Specimen Bank for broad-scale, long-term monitoring of ocean acidification and the associated impacts to coral reefs. Concurrent analyses of other trace elements, heavy metals, and isotopes in these samples will also be performed to assess their utility as biosensors for additional water chemistry parameters on coral reefs.

  2. Nitrogen and phosphorus uptake rates of different species from a coral reef community after a nutrient pulse

    NASA Astrophysics Data System (ADS)

    den Haan, Joost; Huisman, Jef; Brocke, Hannah J.; Goehlich, Henry; Latijnhouwers, Kelly R. W.; van Heeringen, Seth; Honcoop, Saskia A. S.; Bleyenberg, Tanja E.; Schouten, Stefan; Cerli, Chiara; Hoitinga, Leo; Vermeij, Mark J. A.; Visser, Petra M.

    2016-06-01

    Terrestrial runoff after heavy rainfall can increase nutrient concentrations in waters overlying coral reefs that otherwise experience low nutrient levels. Field measurements during a runoff event showed a sharp increase in nitrate (75-fold), phosphate (31-fold) and ammonium concentrations (3-fold) in waters overlying a fringing reef at the island of Curaçao (Southern Caribbean). To understand how benthic reef organisms make use of such nutrient pulses, we determined ammonium, nitrate and phosphate uptake rates for one abundant coral species, turf algae, six macroalgal and two benthic cyanobacterial species in a series of laboratory experiments. Nutrient uptake rates differed among benthic functional groups. The filamentous macroalga Cladophora spp., turf algae and the benthic cyanobacterium Lyngbya majuscula had the highest uptake rates per unit biomass, whereas the coral Madracis mirabilis had the lowest. Combining nutrient uptake rates with the standing biomass of each functional group on the reef, we estimated that the ammonium and phosphate delivered during runoff events is mostly taken up by turf algae and the two macroalgae Lobophora variegata and Dictyota pulchella. Our results support the often proposed, but rarely tested, assumption that turf algae and opportunistic macroalgae primarily benefit from episodic inputs of nutrients to coral reefs.

  3. Nitrogen and phosphorus uptake rates of different species from a coral reef community after a nutrient pulse

    PubMed Central

    den Haan, Joost; Huisman, Jef; Brocke, Hannah J.; Goehlich, Henry; Latijnhouwers, Kelly R. W.; van Heeringen, Seth; Honcoop, Saskia A. S.; Bleyenberg, Tanja E.; Schouten, Stefan; Cerli, Chiara; Hoitinga, Leo; Vermeij, Mark J. A.; Visser, Petra M.

    2016-01-01

    Terrestrial runoff after heavy rainfall can increase nutrient concentrations in waters overlying coral reefs that otherwise experience low nutrient levels. Field measurements during a runoff event showed a sharp increase in nitrate (75-fold), phosphate (31-fold) and ammonium concentrations (3-fold) in waters overlying a fringing reef at the island of Curaçao (Southern Caribbean). To understand how benthic reef organisms make use of such nutrient pulses, we determined ammonium, nitrate and phosphate uptake rates for one abundant coral species, turf algae, six macroalgal and two benthic cyanobacterial species in a series of laboratory experiments. Nutrient uptake rates differed among benthic functional groups. The filamentous macroalga Cladophora spp., turf algae and the benthic cyanobacterium Lyngbya majuscula had the highest uptake rates per unit biomass, whereas the coral Madracis mirabilis had the lowest. Combining nutrient uptake rates with the standing biomass of each functional group on the reef, we estimated that the ammonium and phosphate delivered during runoff events is mostly taken up by turf algae and the two macroalgae Lobophora variegata and Dictyota pulchella. Our results support the often proposed, but rarely tested, assumption that turf algae and opportunistic macroalgae primarily benefit from episodic inputs of nutrients to coral reefs. PMID:27353576

  4. Late Miocene Coral faunas of Iran (Zagros, Aghar, Firuz abad, Fars) palaeoecology and palaeobiogeography

    NASA Astrophysics Data System (ADS)

    Dehbozorgi, M.; Yazdi, M.; Torabi, H.

    2009-04-01

    Late Miocene Corals assemblage from Zagros Iran are investigated with respect to their palaeoecology and palaeobiogeography implications. This Corals are compared with fauna from Mediterranean Tethys and the Indopacific. Small foraminifers are used for biogeography and to support paleoecology interpretation. The studied section situated in the Zagros Mishan F.m is last depositions sea. A distinct horizon characterized by Porites- Antiguastrea assemblage associated Milliolid and Rotalia is interpreted a shallow bioclastic shoal. Patch reef with a porites and faviidae assemblage are a common feature of Oligocene and Miocene coral occurrence and indicate water depth of less than 20m. The diversity of corals in this area are low and all corals are hematypic. Miocene Corals from Mishan F.m Comprise 7 genera and occur in the single horizon or patch reef. This Corals and patch reefs are compared with corals and patch reefs in Qom F.m Central Iran. This corals report from this section: Antiguastrea sp., Monastrea sp., Favites sp., Porites sp., Dichocoenia sp., Asterohelia sp., Leptoria sp. Keywords: Miocene- Iran- Mishan-Zagros- Formation- Tethys seaway- Corals- Palaeoecology- palaeobiogeography.

  5. Ten years of change to coral communities off Mona and Desecheo Islands, Puerto Rico, from disease and bleaching.

    PubMed

    Bruckner, Andrew W; Hill, Ronald L

    2009-11-16

    Remote reefs off southwest Puerto Rico have experienced recent losses in live coral cover of 30 to 80%, primarily due to the decline of Montastraea annularis and M. faveolata from disease and bleaching. These species were formerly the largest, oldest, and most abundant corals on these reefs, constituting over 65% of the living coral cover and 40 to 80% of the total number of colonies. From 1998 to 2001, outbreaks of yellow band disease (YBD) and white plague (WP) affected 30 to 60% of the M. annularis (complex) colonies. Disease prevalence declined beginning in 2002, and then increased immediately following the 2005 mass bleaching event. Colonies of M. annularis (complex) have been reduced in abundance by 24 to 32%, and remaining colonies are missing more than half their tissue. Both M. annularis and M. faveolata have failed to recruit, resheeting has been minimal, and exposed skeletal surfaces are being colonized by macroalgae, bioeroding sponges, and hydrozoans. Other scleractinian corals were smaller in size (mean = 28 cm diameter) and exhibited lower levels of partial mortality; these taxa were affected to a lesser extent by coral diseases and bleaching-associated tissue loss over the last decade. The numbers of small colonies (1 to 9 cm) of these species identified since 2005 also exceeded numbers of larger colonies that died. These reefs appear to be exhibiting shifts in species assemblages, with replacement of M. annularis (complex) by shorter-lived brooding species and other massive and plating corals (Agaricia, Porites, Meandrina, Eusmilia, Diploria, and Siderastrea spp.). To avoid a catastrophic and permanent loss of the dominant, slow-growing reef-building corals, the causes and effects of diseases need to be better understood, and possible control mechanisms must be developed. In particular, steps must be taken to mitigate environmental and anthropogenic stressors that increase the spread and severity of disease.

  6. Cyphastrea kausti sp. n. (Cnidaria, Anthozoa, Scleractinia), a new species of reef coral from the Red Sea

    PubMed Central

    Bouwmeester, Jessica; Benzoni, Francesca; Baird, Andrew H.; Berumen, Michael L.

    2015-01-01

    Abstract A new scleractinian coral species, Cyphastrea kausti sp. n., is described from 13 specimens from the Red Sea. It is characterised by the presence of eight primary septa, unlike the other species of the genus, which have six, ten or 12 primary septa. The new species has morphological affinities with Cyphastrea microphthalma, from which it can be distinguished by the lower number of septa (on average eight instead of ten), and smaller calices and corallites. This species was observed in the northern and central Red Sea and appears to be absent from the southern Red Sea. PMID:25931952

  7. Wet Season Upwelling and Dry Season Chlorophyll-a Describe Interannual Growth Rates of Porites in Southern China

    PubMed Central

    Yang, Teng Teng; Goodkin, Nathalie Fairbank

    2014-01-01

    Southern China hosts coral communities in marginal environments that are characterized by low linear extension rates, low coral cover and/or no reef formation, thus providing natural laboratories to study coral communities with below average growth rates. Here we compare the annual linear extension rates over 10 years (range 1.2 to 11.4 mm yr−1) of six Porites sp. coral cores collected from Hong Kong with monthly hydrographic data from the Hong Kong Environmental Protection Department. At all sites, low-density, dry season extension were more variable than high-density, wet season extension and on average, was lower at two of the three sites. We applied multi-variate linear regressions that revealed high-density, wet season band extension to inversely correlate most significantly to temperature (r = −0.39, p<0.01). In contrast, low-density, dry season band extension was more variable and correlated most significantly with dry season chlorophyll-a (Chl-a) (r = 0.64, p<0.001). Additionally, we find that corals at the site with highest dry season Chl-a have the highest dry season extension lengths. Our findings indicate that relative mixing of fresh and salt water in the wet season and primary productivity in the dry season, and their influences on aragonite saturation, are likely to impact interannual coral extension variability in marginal environments. PMID:24901939

  8. Internal pH regulation facilitates in situ long-term acclimation of massive corals to end-of-century carbon dioxide conditions

    NASA Astrophysics Data System (ADS)

    Wall, M.; Fietzke, J.; Schmidt, G. M.; Fink, A.; Hofmann, L. C.; de Beer, D.; Fabricius, K. E.

    2016-08-01

    The resilience of tropical corals to ocean acidification depends on their ability to regulate the pH within their calcifying fluid (pHcf). Recent work suggests pHcf homeostasis under short-term exposure to pCO2 conditions predicted for 2100, but it is still unclear if pHcf homeostasis can be maintained throughout a corals lifetime. At CO2 seeps in Papua New Guinea, massive Porites corals have grown along a natural seawater pH gradient for decades. This natural gradient, ranging from pH 8.1–7.4, provides an ideal platform to determine corals’ pHcf (using boron isotopes). Porites maintained a similar pHcf (~8.24) at both a control (pH 8.1) and seep-influenced site (pH 7.9). Internal pHcf was slightly reduced (8.12) at seawater pH 7.6, and decreased to 7.94 at a site with a seawater pH of 7.4. A growth response model based on pHcf mirrors the observed distribution patterns of this species in the field. We suggest Porites has the capacity to acclimate after long-time exposure to end-of-century reduced seawater pH conditions and that strong control over pHcf represents a key mechanism to persist in future oceans. Only beyond end-of-century pCO2 conditions do they face their current physiological limit of pH homeostasis and pHcf begins to decrease.

  9. Internal pH regulation facilitates in situ long-term acclimation of massive corals to end-of-century carbon dioxide conditions

    PubMed Central

    Wall, M.; Fietzke, J.; Schmidt, G. M.; Fink, A; Hofmann, L. C.; de Beer, D.; Fabricius, K. E.

    2016-01-01

    The resilience of tropical corals to ocean acidification depends on their ability to regulate the pH within their calcifying fluid (pHcf). Recent work suggests pHcf homeostasis under short-term exposure to pCO2 conditions predicted for 2100, but it is still unclear if pHcf homeostasis can be maintained throughout a corals lifetime. At CO2 seeps in Papua New Guinea, massive Porites corals have grown along a natural seawater pH gradient for decades. This natural gradient, ranging from pH 8.1–7.4, provides an ideal platform to determine corals’ pHcf (using boron isotopes). Porites maintained a similar pHcf (~8.24) at both a control (pH 8.1) and seep-influenced site (pH 7.9). Internal pHcf was slightly reduced (8.12) at seawater pH 7.6, and decreased to 7.94 at a site with a seawater pH of 7.4. A growth response model based on pHcf mirrors the observed distribution patterns of this species in the field. We suggest Porites has the capacity to acclimate after long-time exposure to end-of-century reduced seawater pH conditions and that strong control over pHcf represents a key mechanism to persist in future oceans. Only beyond end-of-century pCO2 conditions do they face their current physiological limit of pH homeostasis and pHcf begins to decrease. PMID:27477963

  10. Species Specificity of Bacteria Associated to the Brown Seaweeds Lobophora (Dictyotales, Phaeophyceae) and Their Potential for Induction of Rapid Coral Bleaching in Acropora muricata

    PubMed Central

    Vieira, Christophe; Engelen, Aschwin H.; Guentas, Linda; Aires, Tânia; Houlbreque, Fanny; Gaubert, Julie; Serrão, Ester A.; De Clerck, Olivier; Payri, Claude E.

    2016-01-01

    While reef degradation is occurring worldwide, it is not uncommon to see phase shifts from coral to macroalgal dominated reefs. Numerous studies have addressed the mechanisms by which macroalgae may outcompete corals and a few recent studies highlighted the putative role of bacteria at the interface between macroalgae and corals. Some studies suggest that macroalgae may act as vectors and/or foster proliferation of microorganisms pathogenic for corals. Using a combination of high throughput sequencing, bacterial culturing, and in situ bioassays we question if the adversity of macroalgal-associated bacteria to corals is mediated by specific bacterial taxa. Using Illumina sequencing, we characterized and compared the bacterial community from two Lobophora (Dictyotales, Phaeophyceae) species. The two species presented distinctive bacterial communities. Both species shared approximately half of their OTUs, mainly the most abundant bacteria. Species-specific OTUs belong to Planctomycetes, Proteobacteria, and Bacteroidetes. In total, 16 culturable bacterial strain were isolated and identified from the Lobophora surface, consisting of 10 genera (from nine families, four classes, and three phyla), some of which are not known as, but are related to pathogens involved in coral diseases, and others are naturally associated to corals. When patches of marine agar with 24 h cultures of each of these bacteria were placed in direct contact with the branches of the scleractinian coral Acropora muricata, they caused severe bleaching after 24 h exposure. Results suggest that regardless of taxonomic affinities, increase in density of these bacteria can be adverse to corals. Nevertheless, the microbial community associated to macroalgal surface may not represent a threat to corals, because the specific bacterial screening and control exerted by the alga preventing specific bacterial proliferation. PMID:27047453

  11. Species Specificity of Bacteria Associated to the Brown Seaweeds Lobophora (Dictyotales, Phaeophyceae) and Their Potential for Induction of Rapid Coral Bleaching in Acropora muricata.

    PubMed

    Vieira, Christophe; Engelen, Aschwin H; Guentas, Linda; Aires, Tânia; Houlbreque, Fanny; Gaubert, Julie; Serrão, Ester A; De Clerck, Olivier; Payri, Claude E

    2016-01-01

    While reef degradation is occurring worldwide, it is not uncommon to see phase shifts from coral to macroalgal dominated reefs. Numerous studies have addressed the mechanisms by which macroalgae may outcompete corals and a few recent studies highlighted the putative role of bacteria at the interface between macroalgae and corals. Some studies suggest that macroalgae may act as vectors and/or foster proliferation of microorganisms pathogenic for corals. Using a combination of high throughput sequencing, bacterial culturing, and in situ bioassays we question if the adversity of macroalgal-associated bacteria to corals is mediated by specific bacterial taxa. Using Illumina sequencing, we characterized and compared the bacterial community from two Lobophora (Dictyotales, Phaeophyceae) species. The two species presented distinctive bacterial communities. Both species shared approximately half of their OTUs, mainly the most abundant bacteria. Species-specific OTUs belong to Planctomycetes, Proteobacteria, and Bacteroidetes. In total, 16 culturable bacterial strain were isolated and identified from the Lobophora surface, consisting of 10 genera (from nine families, four classes, and three phyla), some of which are not known as, but are related to pathogens involved in coral diseases, and others are naturally associated to corals. When patches of marine agar with 24 h cultures of each of these bacteria were placed in direct contact with the branches of the scleractinian coral Acropora muricata, they caused severe bleaching after 24 h exposure. Results suggest that regardless of taxonomic affinities, increase in density of these bacteria can be adverse to corals. Nevertheless, the microbial community associated to macroalgal surface may not represent a threat to corals, because the specific bacterial screening and control exerted by the alga preventing specific bacterial proliferation.

  12. Predictive modeling of coral disease distribution within a reef system.

    PubMed

    Williams, Gareth J; Aeby, Greta S; Cowie, Rebecca O M; Davy, Simon K

    2010-02-17

    Diseases often display complex and distinct associations with their environment due to differences in etiology, modes of transmission between hosts, and the shifting balance between pathogen virulence and host resistance. Statistical modeling has been underutilized in coral disease research to explore the spatial patterns that result from this triad of interactions. We tested the hypotheses that: 1) coral diseases show distinct associations with multiple environmental factors, 2) incorporating interactions (synergistic collinearities) among environmental variables is important when predicting coral disease spatial patterns, and 3) modeling overall coral disease prevalence (the prevalence of multiple diseases as a single proportion value) will increase predictive error relative to modeling the same diseases independently. Four coral diseases: Porites growth anomalies (PorGA), Porites tissue loss (PorTL), Porites trematodiasis (PorTrem), and Montipora white syndrome (MWS), and their interactions with 17 predictor variables were modeled using boosted regression trees (BRT) within a reef system in Hawaii. Each disease showed distinct associations with the predictors. Environmental predictors showing the strongest overall associations with the coral diseases were both biotic and abiotic. PorGA was optimally predicted by a negative association with turbidity, PorTL and MWS by declines in butterflyfish and juvenile parrotfish abundance respectively, and PorTrem by a modal relationship with Porites host cover. Incorporating interactions among predictor variables contributed to the predictive power of our models, particularly for PorTrem. Combining diseases (using overall disease prevalence as the model response), led to an average six-fold increase in cross-validation predictive deviance over modeling the diseases individually. We therefore recommend coral diseases to be modeled separately, unless known to have etiologies that respond in a similar manner to particular

  13. Predictive Modeling of Coral Disease Distribution within a Reef System

    PubMed Central

    Williams, Gareth J.; Aeby, Greta S.; Cowie, Rebecca O. M.; Davy, Simon K.

    2010-01-01

    Diseases often display complex and distinct associations with their environment due to differences in etiology, modes of transmission between hosts, and the shifting balance between pathogen virulence and host resistance. Statistical modeling has been underutilized in coral disease research to explore the spatial patterns that result from this triad of interactions. We tested the hypotheses that: 1) coral diseases show distinct associations with multiple environmental factors, 2) incorporating interactions (synergistic collinearities) among environmental variables is important when predicting coral disease spatial patterns, and 3) modeling overall coral disease prevalence (the prevalence of multiple diseases as a single proportion value) will increase predictive error relative to modeling the same diseases independently. Four coral diseases: Porites growth anomalies (PorGA), Porites tissue loss (PorTL), Porites trematodiasis (PorTrem), and Montipora white syndrome (MWS), and their interactions with 17 predictor variables were modeled using boosted regression trees (BRT) within a reef system in Hawaii. Each disease showed distinct associations with the predictors. Environmental predictors showing the strongest overall associations with the coral diseases were both biotic and abiotic. PorGA was optimally predicted by a negative association with turbidity, PorTL and MWS by declines in butterflyfish and juvenile parrotfish abundance respectively, and PorTrem by a modal relationship with Porites host cover. Incorporating interactions among predictor variables contributed to the predictive power of our models, particularly for PorTrem. Combining diseases (using overall disease prevalence as the model response), led to an average six-fold increase in cross-validation predictive deviance over modeling the diseases individually. We therefore recommend coral diseases to be modeled separately, unless known to have etiologies that respond in a similar manner to particular

  14. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (south Florida): Reef-building corals. [Acropora cervicornis; Acropora palmata; Montastraea annularis; Montastraea cavernosa

    SciTech Connect

    Porter, J.W.

    1987-08-01

    Four species of reef-building corals are considered: elkhorn coral, staghorn coral, common star coral, and large star coral. All four species spawn annually in the fall during hurricane season. Juvenile recruitment is low in all four species. Rapid growth rates of species in the genus Acropora (10 to 20 cm/yr) contrast with slower growth rates of species in the genus Montastraea (1.0 to 2.0 cm/yr), but both species of Montastraea are also important in reef development due to their form and great longevity. Shallow-water colonies of Montastraea survive hurricanes; shallow colonies of Acropora do not. Because of their dependence on photosynthesis for all of their carbon acquisition, the Acropora species reviewed here have a more restricted depth distribution (0 to 30 m) than do the Montastraea species considered (0 to 70 m). All four species are subject to intense predation by the snail predator, Coralliophila. Species of Montastraea are susceptible to infection from blue-green algae, which produce ''black band disease;'' species of Acropora are susceptible to a different, as yet unidentified pathogen, that produces ''white-band'' disease. Increased water turbidity and sedimentation cause reduced growth rates and partial or whole mortality in all four species.

  15. External carbonic anhydrase in three Caribbean corals: quantification of activity and role in CO2 uptake

    NASA Astrophysics Data System (ADS)

    Tansik, Anna L.; Fitt, William K.; Hopkinson, Brian M.

    2015-09-01

    Scleractinian corals have complicated inorganic carbon ( C i) transport pathways to support both photosynthesis, by their symbiotic dinoflagellates, and calcification. The first step in C i acquisition, uptake into the coral, is critical as the diffusive boundary layer limits the supply of CO2 to the surface and HCO3 - uptake is energy intensive. An external carbonic anhydrase (eCA) on the oral surface of corals is thought to facilitate CO2 uptake by converting HCO3 - into CO2, helping to overcome the limitation imposed by the boundary layer. However, this enzyme has not yet been identified or detected in corals, nor has its activity been quantified. We have developed a method to quantify eCA activity using a reaction-diffusion model to analyze data on 18O removal from labeled C i. Applying this technique to three species of Caribbean corals ( Orbicella faveolata, Porites astreoides, and Siderastrea radians) showed that all species have eCA and that the potential rates of CO2 generation by eCA greatly exceed photosynthetic rates. This demonstrates that eCA activity is sufficient to support its hypothesized role in CO2 supply. Inhibition of eCA severely reduces net photosynthesis in all species (on average by 46 ± 27 %), implying that CO2 generated by eCA is a major carbon source for photosynthesis. Because of the high permeability of membranes to CO2, CO2 uptake is likely driven by a concentration gradient across the cytoplasmic membrane. The ubiquity of eCA in corals from diverse genera and environments suggests that it is fundamental for photosynthetic CO2 supply.

  16. SIMULATED SOLAR ULTRAVIOLET RADIATION EFFECTS ON 5 SPECIES OF SCLERACTINIAN CORALS

    EPA Science Inventory

    The impact of global climate change factors such as increased temperature and ultraviolet radiation (UVR) on coral bleaching are of continued interest to the USEPA. Coral bleaching occurs when symbiotic zooxanthellae and/or their pigments are depleted in response to stressors suc...

  17. Episodic Eruptions of Volcanic Ash Trigger a Reversible Cascade of Nuisance Species Outbreaks in Pristine Coral Habitats

    PubMed Central

    Schils, Tom

    2012-01-01

    Volcanically active islands abound in the tropical Pacific and harbor complex coral communities. Whereas lava streams and deep ash deposits are well-known to devastate coral communities through burial and smothering, little is known about the effect of moderate amounts of small particulate ash deposits on reef communities. Volcanic ash contains a diversity of chemical compounds that can induce nutrient enrichments triggering changes in benthic composition. Two independently collected data sets on the marine benthos of the pristine and remote reefs around Pagan Island, Northern Mariana Islands, reveal a sudden critical transition to cyanobacteria-dominated communities in 2009–2010, which coincides with a period of continuous volcanic ash eruptions. Concurrently, localized outbreaks of the coral-killing cyanobacteriosponge Terpios hoshinota displayed a remarkable symbiosis with filamentous cyanobacteria, which supported the rapid overgrowth of massive coral colonies and allowed the sponge to colonize substrate types from which it has not been documented before. The chemical composition of tephra from Pagan indicates that the outbreak of nuisance species on its reefs might represent an early succession stage of iron enrichment (a.k.a. “black reefs”) similar to that caused by anthropogenic debris like ship wrecks or natural events like particulate deposition from wildfire smoke plumes or desert dust storms. Once Pagan's volcanic activity ceased in 2011, the cyanobacterial bloom disappeared. Another group of well-known nuisance algae in the tropical Pacific, the pelagophytes, did not reach bloom densities during this period of ash eruptions but new species records for the Northern Mariana Islands were documented. These field observations indicate that the study of population dynamics of pristine coral communities can advance our understanding of the resilience of tropical reef systems to natural and anthropogenic disturbances. PMID:23056381

  18. Episodic eruptions of volcanic ash trigger a reversible cascade of nuisance species outbreaks in pristine coral habitats.

    PubMed

    Schils, Tom

    2012-01-01

    Volcanically active islands abound in the tropical Pacific and harbor complex coral communities. Whereas lava streams and deep ash deposits are well-known to devastate coral communities through burial and smothering, little is known about the effect of moderate amounts of small particulate ash deposits on reef communities. Volcanic ash contains a diversity of chemical compounds that can induce nutrient enrichments triggering changes in benthic composition. Two independently collected data sets on the marine benthos of the pristine and remote reefs around Pagan Island, Northern Mariana Islands, reveal a sudden critical transition to cyanobacteria-dominated communities in 2009-2010, which coincides with a period of continuous volcanic ash eruptions. Concurrently, localized outbreaks of the coral-killing cyanobacteriosponge Terpios hoshinota displayed a remarkable symbiosis with filamentous cyanobacteria, which supported the rapid overgrowth of massive coral colonies and allowed the sponge to colonize substrate types from which it has not been documented before. The chemical composition of tephra from Pagan indicates that the outbreak of nuisance species on its reefs might represent an early succession stage of iron enrichment (a.k.a. "black reefs") similar to that caused by anthropogenic debris like ship wrecks or natural events like particulate deposition from wildfire smoke plumes or desert dust storms. Once Pagan's volcanic activity ceased in 2011, the cyanobacterial bloom disappeared. Another group of well-known nuisance algae in the tropical Pacific, the pelagophytes, did not reach bloom densities during this period of ash eruptions but new species records for the Northern Mariana Islands were documented. These field observations indicate that the study of population dynamics of pristine coral communities can advance our understanding of the resilience of tropical reef systems to natural and anthropogenic disturbances.

  19. Complete mitochondrial genome sequences of Atlantic representatives of the invasive Pacific coral species Tubastraea coccinea and T. tagusensis (Scleractinia, Dendrophylliidae): Implications for species identification.

    PubMed

    Capel, K C C; Migotto, A E; Zilberberg, C; Lin, M F; Forsman, Z; Miller, D J; Kitahara, M V

    2016-09-30

    Members of the azooxanthellate coral genus Tubastraea are invasive species with particular concern because they have become established and are fierce competitors in the invaded areas in many parts of the world. Pacific Tubastraea species are spreading fast throughout the Atlantic Ocean, occupying over 95% of the available substrate in some areas and out-competing native endemic species. Approximately half of all known coral species are azooxanthellate but these are seriously under-represented compared to zooxanthellate corals in terms of the availability of mitochondrial (mt) genome data. In the present study, the complete mt DNA sequences of Atlantic individuals of the invasive scleractinian species Tubastraea coccinea and Tubastraea tagusensis were determined and compared to the GenBank reference sequence available for a Pacific "T. coccinea" individual. At 19,094bp (compared to 19,070bp for the GenBank specimen), the mt genomes assembled for the Atlantic T. coccinea and T. tagusensis were among the longest sequence determined to date for "Complex" scleractinians. Comparisons of genomes data showed that the "T. coccinea" sequence deposited on GenBank was more closely related to that from Dendrophyllia arbuscula than to the Atlantic Tubastraea spp., in terms of genome length and base pair similarities. This was confirmed by phylogenetic analysis, suggesting that the former was misidentified and might actually be a member from the genus Dendrophyllia. In addition, although in general the COX1 locus has a slow evolutionary rate in Scleractinia, it was the most variable region of the Tubastraea mt genome and can be used as markers for genus or species identification. Given the limited data available for azooxanthellate corals, the results presented here represent an important contribution to our understanding of phylogenetic relationships and the evolutionary history of the Scleractinia.

  20. Reproductive ecology of four scleratinian species at Lizard Island, Great Barrier Reef

    NASA Astrophysics Data System (ADS)

    Harriott, V. J.

    1983-08-01

    Reproductive ecology of four scleractinian species, Lobophyllia corymbosa, Favia favus, Porties lutea and Porites australiensis was studied for two years on a patch reef near Lizard Island. Two major reproductive patterns were found: L. corymbosa and F. favus were simultaneous hermaphrodites and released gametes over several days in summer; and P. lutea, and P. australiensis were dioecious and released gametes over several weeks to several months respectively, in summer. Three of the four species spawned predominantly in the lunar period between the full and last quarter moon. In all four species, ovaries began developing several months earlier than testes. Number of ova per colony varied greatly amongst the species and was inversely related to mature egg size. The results presented here contrast with earlier assumptions of almost uniform viviparity of corals and supports the generalization that a brief annual spawning period with larvae developing externally may prove to be the dominant form of sexual reproduction in hermatypic corals.

  1. Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (South Florida). Reef-Building Corals.

    DTIC Science & Technology

    1987-08-01

    Stoddart, D.R. 1969. Ecology and Sammarco, P.W. 1985. The Great morphology of recent coral reefs . Barrier Reef vs. the Caribbean: Biol. Rev. Camb. Philos...Sambo Reef , Florida, involving cervicornis and M. annularis tolerated bleaching and loss of symbiotic oxygen tensions as low as 1.0 ppm for zooxanthellae...Montastraea (1.0-2.0 cm/yr), but both species of Montastraea are also important in reef development due to their massive form and great longevity

  2. Modeling Surface Water Transport in the Central Pacific Ocean With 129I Records From Coral Skeletons

    NASA Astrophysics Data System (ADS)

    Beck, W.; Biddulph, D. L.; Russell, J. L.; Burr, G. S.; Jull, T. J.; Correge, T.; Roeder, B.

    2008-12-01

    129I occurs naturally in extremely low abundance via cosmic ray interactions in the atmosphere as well as by spontaneous fission of uranium. Oceanic concentrations of 129I have risen by several orders of magnitude during the last half century largely from environmental pollution coming from several point-source nuclear fuel reprocessing plants. In the Pacific basin, much of the increase has apparently come from the Hanford Nuclear reprocessing plant in the United States, with iodine primarily arriving via the Columbia River. Coral skeletons preserve records of 129I concentration of the surface waters from which they were deposited, yielding records with annual resolution or better. We will present three such records from different locations in the Pacific Ocean: the Solomon Islands, Easter Island and Clipperton Atoll. For this study, drill cores from living massive coral skeletons of the species Porites Lobata were collected from these sites. 129I/127I values were measured using accelerator mass spectrometry (AMS) at the University of Arizona with an NEC 3 MV Pelletron accelerator. Results from the analysis of the corals will be compared to the distribution of other mixed-layer tracers (chloro-fluorocarbons and tritium) collected during the World Ocean Circulation Experiment cruises conducted between 1990 and 2002. The 129I/127I records observed in these corals will also be compared to tracer transit time calculations determined from a 20th century simulation of the GFDL coupled-climate passive-tracer model.

  3. Reef flattening effects on total richness and species responses in the Caribbean.

    PubMed

    Newman, Steven P; Meesters, Erik H; Dryden, Charlie S; Williams, Stacey M; Sanchez, Cristina; Mumby, Peter J; Polunin, Nicholas V C

    2015-11-01

    There has been ongoing flattening of Caribbean coral reefs with the loss of habitat having severe implications for these systems. Complexity and its structural components are important to fish species richness and community composition, but little is known about its role for other taxa or species-specific responses. This study reveals the importance of reef habitat complexity and structural components to different taxa of macrofauna, total species richness, and individual coral and fish species in the Caribbean. Species presence and richness of different taxa were visually quantified in one hundred 25-m(2) plots in three marine reserves in the Caribbean. Sampling was evenly distributed across five levels of visually estimated reef complexity, with five structural components also recorded: the number of corals, number of large corals, slope angle, maximum sponge and maximum octocoral height. Taking advantage of natural heterogeneity in structural complexity within a particular coral reef habitat (Orbicella reefs) and discrete environmental envelope, thus minimizing other sources of variability, the relative importance of reef complexity and structural components was quantified for different taxa and individual fish and coral species on Caribbean coral reefs using boosted regression trees (BRTs). Boosted regression tree models performed very well when explaining variability in total (82·3%), coral (80·6%) and fish species richness (77·3%), for which the greatest declines in richness occurred below intermediate reef complexity levels. Complexity accounted for very little of the variability in octocorals, sponges, arthropods, annelids or anemones. BRTs revealed species-specific variability and importance for reef complexity and structural components. Coral and fish species occupancy generally declined at low complexity levels, with the exception of two coral species (Pseudodiploria strigosa and Porites divaricata) and four fish species (Halichoeres bivittatus, H

  4. Ocean acidification causes bleaching and productivity loss in coral reef builders.

    PubMed

    Anthony, K R N; Kline, D I; Diaz-Pulido, G; Dove, S; Hoegh-Guldberg, O

    2008-11-11

    Ocean acidification represents a key threat to coral reefs by reducing the calcification rate of framework builders. In addition, acidification is likely to affect the relationship between corals and their symbiotic dinoflagellates and the productivity of this association. However, little is known about how acidification impacts on the physiology of reef builders and how acidification interacts with warming. Here, we report on an 8-week study that compared bleaching, productivity, and calcification responses of crustose coralline algae (CCA) and branching (Acropora) and massive (Porites) coral species in response to acidification and warming. Using a 30-tank experimental system, we manipulated CO(2) levels to simulate doubling and three- to fourfold increases [Intergovernmental Panel on Climate Change (IPCC) projection categories IV and VI] relative to present-day levels under cool and warm scenarios. Results indicated that high CO(2) is a bleaching agent for corals and CCA under high irradiance, acting synergistically with warming to lower thermal bleaching thresholds. We propose that CO(2) induces bleaching via its impact on photoprotective mechanisms of the photosystems. Overall, acidification impacted more strongly on bleaching and productivity than on calcification. Interestingly, the intermediate, warm CO(2) scenario led to a 30% increase in productivity in Acropora, whereas high CO(2) lead to zero productivity in both corals. CCA were most sensitive to acidification, with high CO(2) leading to negative productivity and high rates of net dissolution. Our findings suggest that sensitive reef-building species such as CCA may be pushed beyond their thresholds for growth and survival within the next few decades whereas corals will show delayed and mixed responses.

  5. Sedimentologic succession of uplifted coral community, Urvina Bay, Isabela Island, Galapagos Archipelago, Ecuador

    SciTech Connect

    Colgan, M.W.; Hollander, D.

    1987-05-01

    In March 1954, along the west-central coast of Isabela Island, an upward movement of magma suddenly raised Urvina Bay over 6 m and exposed several square kilometers of carbonate deposits covering a young aa lava flow (around 1000 years old). Results from 6 transect lines across the uplift, 30 cores, and 10 trenches describe the sedimentologic and ecologic transition from barren basalt to diverse carbonate sediments with small coral reefs. Along horizontal transects spanning from 0 to 7 m paleowater depth, there is a seaward progression from beaches, mangroves, and basalt to thick deposits (> 1.6 m) of carbonate sands and small coral reefs. Variation in water depth, degree of wave exposure, and irregularity of the aa lava topography provided many microhabitats where coral, calcareous algae, and mollusks settled and grew. Eight hermatypic coral species are found throughout the shelf, and three species (i.e., Pavona clavus, Pocillopora damicornis, and Porites lobata) produced five small, isolated, monospecific, coral-reef frameworks. The vertical section seen in cores and trenches shows that calcium carbonate increased upward, whereas volcanic sediments decreased; however, episodic layers occur with high concentrations of basaltic sands. In vertical samples from the central portion of the shelf, the coral population changed from small, isolated colonies of Psammocora (Plesioseris) superficalis near the basalt basement to large reef-forming colonies of Pocillopora damicornis farther upsection. Reefs of the Galapagos Islands are small and less diverse than most Pacific reefs. Nonetheless, understanding their temporal successional development should throw light on the origin and history of larger oceanic reefs in the Pacific.

  6. Interactive effects of three pervasive marine stressors in a post-disturbance coral reef

    NASA Astrophysics Data System (ADS)

    Gil, Michael A.; Goldenberg, Silvan U.; Ly Thai Bach, Anne; Mills, Suzanne C.; Claudet, Joachim

    2016-12-01

    Ecosystems are commonly affected by natural, episodic disturbances that can abruptly and drastically alter communities. Although it has been shown that resilient ecosystems can eventually recover to pre-disturbed states, the extent to which communities in early stages of recovery could be affected by multiple anthropogenic stressors is poorly understood. Pervasive and rising anthropogenic stressors in coastal marine systems that could interactively affect the recovery of these systems following natural disturbances include high sedimentation, nutrient enrichment, and overfishing. Using a 6-month field experiment, we examined the effects of all combinations of these three stressors on key functional groups in the benthic community growing on simulated, post-disturbance reef patches within a system recovering from large-scale natural disturbances (corallivorous seastar outbreak and cyclone). Our study revealed that sedimentation, nutrient enrichment, and overfishing (simulated using exclusion cages) interactively affected coral survival and algal growth, with taxon-specific effects at multiple scales. First, our treatments affected corals and algae differently, with sedimentation being more detrimental to macroalgal growth but less detrimental to coral ( Porites rus) survival in caged plots, driving significant interactions between sedimentation and caging for both taxa. We also observed distinct responses between coral species and between algal functional groups, with the most extensive responses from algal turf biomass, for which sedimentation suppressed the synergistic (positive) combined effect of nutrient enrichment and caging. Our findings suggest that different combinations of ubiquitous anthropogenic stressors, related to either sea- or land-based activities, interactively influence community recovery from disturbance and may alter species compositions in the resulting community. Our findings further suggest that anthropogenic stressors could promote further

  7. Assessing Gear Modifications Needed to Optimize Yields in a Heavily Exploited, Multi-Species, Seagrass and Coral Reef Fishery

    PubMed Central

    Hicks, Christina C.; McClanahan, Timothy R.

    2012-01-01

    Effective management is necessary if small-scale fisheries, such as those found in mixed habitats including seagrass and coral reefs, are to continue providing food for many of the poorest communities of the world. Gear-based management, although under represented and under studied, has the potential to be adaptive, address multiple objectives, and be crafted to the socio-economic setting. Management effectiveness in seagrass and coral reef fisheries has generally been evaluated at the scale of the fish community. However, community level indicators can mask species-specific declines that provide significant portions of the fisheries yields and income. Using a unique dataset, containing ten years of species level length frequency catch data from a multi-gear, multi-species seagrass and coral reef fishery in Kenya, we evaluate species specific fishery statuses, compare gear use to gear regulations and estimate the potential needs for further gear restrictions. Despite the high diversity of the fishery, fifteen species represented over 90% of the catch, and only three species represented 60% of the catch. The three most abundant species in the catch, Lethrinus lentjan (Lacepède), Siganus sutor (Valenciennes) and Leptoscarus vaigiensis (Quoy & Gaimard) all showed evidence of growth overfishing. Lethrinus lentjan, with an exploitation rate of 0.82, also shows evidence of recruitment overfishing. Current legal but weakly enforced gear restrictions are capable of protecting a significant portion of the catch up to maturity but optimization of yield will require that the current mesh size be increased from 6.3 to 8.8 and 9.2 cm to increase yields of L. lentjan and S. sutor, respectively. Given the difficulties of enforcing mesh size, we recommend that the economic benefits of these larger mesh sizes be communicated and enforced through co-management. This abstract is also available in Kiswahili (Abstract S1). PMID:22574133

  8. Assessing gear modifications needed to optimize yields in a heavily exploited, multi-species, seagrass and coral reef fishery.

    PubMed

    Hicks, Christina C; McClanahan, Timothy R

    2012-01-01

    Effective management is necessary if small-scale fisheries, such as those found in mixed habitats including seagrass and coral reefs, are to continue providing food for many of the poorest communities of the world. Gear-based management, although under represented and under studied, has the potential to be adaptive, address multiple objectives, and be crafted to the socio-economic setting. Management effectiveness in seagrass and coral reef fisheries has generally been evaluated at the scale of the fish community. However, community level indicators can mask species-specific declines that provide significant portions of the fisheries yields and income. Using a unique dataset, containing ten years of species level length frequency catch data from a multi-gear, multi-species seagrass and coral reef fishery in Kenya, we evaluate species specific fishery statuses, compare gear use to gear regulations and estimate the potential needs for further gear restrictions. Despite the high diversity of the fishery, fifteen species represented over 90% of the catch, and only three species represented 60% of the catch. The three most abundant species in the catch, Lethrinus lentjan (Lacepède), Siganus sutor (Valenciennes) and Leptoscarus vaigiensis (Quoy & Gaimard) all showed evidence of growth overfishing. Lethrinus lentjan, with an exploitation rate of 0.82, also shows evidence of recruitment overfishing. Current legal but weakly enforced gear restrictions are capable of protecting a significant portion of the catch up to maturity but optimization of yield will require that the current mesh size be increased from 6.3 to 8.8 and 9.2 cm to increase yields of L. lentjan and S. sutor, respectively. Given the difficulties of enforcing mesh size, we recommend that the economic benefits of these larger mesh sizes be communicated and enforced through co-management. This abstract is also available in Kiswahili (Abstract S1).

  9. Differential localization of ion transporters suggests distinct cellular mechanisms for calcification and photosynthesis between two coral species.

    PubMed

    Barott, Katie L; Perez, Sidney O; Linsmayer, Lauren B; Tresguerres, Martin

    2015-08-01

    Ion transport is fundamental for multiple physiological processes, including but not limited to pH regulation, calcification, and photosynthesis. Here, we investigated ion-transporting processes in tissues from the corals Acropora yongei and Stylophora pistillata, representatives of the complex and robust clades that diverged over 250 million years ago. Antibodies against complex IV revealed that mitochondria, an essential source of ATP for energetically costly ion transporters, were abundant throughout the tissues of A. yongei. Additionally, transmission electron microscopy revealed septate junctions in all cell layers of A. yongei, as previously reported for S. pistillata, as well as evidence for transcellular vesicular transport in calicoblastic cells. Antibodies against the alpha subunit of Na(+)/K(+)-ATPase (NKA) and plasma membrane Ca(2+)-ATPase (PMCA) immunolabeled cells in the calicoblastic epithelium of both species, suggesting conserved roles in calcification. However, NKA was abundant in the apical membrane of the oral epithelium in A. yongei but not S. pistillata, while PMCA was abundant in the gastroderm of S. pistillata but not A. yongei. These differences indicate that these two coral species utilize distinct pathways to deliver ions to the sites of calcification and photosynthesis. Finally, antibodies against mammalian sodium bicarbonate cotransporters (NBC; SLC4 family) resulted in strong immunostaining in the apical membrane of oral epithelial cells and in calicoblastic cells in A. yongei, a pattern identical to NKA. Characterization of ion transport mechanisms is an essential step toward understanding the cellular mechanisms of coral physiology and will help predict how different coral species respond to environmental stress.

  10. Simultaneous extension of both basic microstructural components in scleractinian coral skeleton during night and daytime, visualized by in situ 86Sr pulse labeling.

    PubMed

    Domart-Coulon, I; Stolarski, J; Brahmi, C; Gutner-Hoch, E; Janiszewska, K; Shemesh, A; Meibom, A

    2014-01-01

    Using in situ (12 h) pulse-labeling of scleractinian coral aragonitic skeleton with stable 86Sr isotope, the diel pattern of skeletal extension was investigated in the massive Porites lobata species, grown at 5 m depth in the Gulf of Eilat. Several microstructural aspects of coral biomineralization were elucidated, among which the most significant is simultaneous extension of the two basic microstructural components Rapid Accretion Deposits (RAD; also called Centers of Calcification) and Thickening Deposits (TD; also called fibers), both at night and during daytime. Increased thickness of the 86Sr-labeled growth-front in the RADs compared to the adjacent TDs revealed that in this species RADs extend on average twice as fast as TDs. At the level of the individual corallite, skeletal extension is spatially highly heterogeneous, with sporadic slowing or cessation depending on growth directions and skeletal structure morphology. Daytime photosynthesis by symbiotic dinoflagellates is widely acknowledged to substantially increase calcification rates at the colony and the corallite level in reef-building corals. However, in our study, the average night-time extension rate (visualized in three successive 12 h pulses) was similar to the average daytime extension (visualized in the initial 12 h pulse), in all growth directions and skeletal structures. This research provides a platform for further investigations into the temporal calibration of coral skeletal extension via cyclic growth increment deposition, which is a hallmark of coral biomineralization.

  11. Impact of recent coastal development and human activities on Nha Trang Bay, Vietnam: evidence from a Porites lutea geochemical record

    NASA Astrophysics Data System (ADS)

    Nguyen, A. D.; Zhao, J.-x.; Feng, Y.-x.; Hu, W.-p.; Yu, K.-f.; Gasparon, M.; Pham, T. B.; Clark, T. R.

    2013-03-01

    Nha Trang Bay (NTB) is located on the Central Vietnam coast, western South China Sea. Recent coastal development of Nha Trang City has raised public concern over an increasing level of pollution within the bay and degradation of nearby coral reefs. In this study, multiple proxies (e.g., trace metals, rare earth elements (REEs), and Y/Ho) recorded in a massive Porites lutea coral colony were used to reconstruct changes in seawater conditions in the NTB from 1995 to 2009. A 14-year record of REEs and other trace metals revealed that the concentrations of terrestrial trace metals have increased dramatically in response to an increase in coastal development projects such as road, port, and resort constructions, port and river dredging, and dumping activities since 2000. The effects of such developmental processes are also evident in changes in REE patterns and Y/Ho ratios through time, suggesting that both parameters are critical proxies for marine pollution.

  12. [Stony coral recruitment in coral reefs at different distances from pollution sources in Habana, Cuba].

    PubMed

    Alcolado-Prieto, Pedro; Caballero Aragón, Hansel; Alcolado, Pedro M; Lopeztegui Castillo, Alexander

    2012-09-01

    The effect of pollution on coral recruitment has been insufficiently studied. This research deals with coral recruitment in coastal areas and aimed to determine the variations of density and dominant species of corals recruits in sites at different distances from pollution sources. The composition and structure of stony coral (scleractinian and milleporids) recruit associations were characterized in the fringing reef of Western Havana, Cuba. This reef is influenced by urban pollution from the Almendares River and a sewage outlet located at its mouth. Four sites were sampled on the upper fore reef escarpment at 10m deep every three months between July 2007 and May 2008. A 25cm side quadrat was used to determine the density and taxonomic composition of recruits smaller than 3cm in diameter. Sampling units were placed following a random-systematic pattern. The mean density of recruits was determined both at assemble and species level. Bifactoral ANOVA tests were applied to compare mean densities at both sampling sites and dates. Student-Newman-Keuls test was applied to compare pairs of means. Cluster and nMDS analyses were applied to evaluate between site similarities. The predominant species was Siderastrea siderea followed by S. radians and Porites astreoides. Recruit densities were similar among La Puntilla, Calle 16 and Acuario sites. Lower densities were always found in Malec6n. Significant differences in mean stony recruit densities were found both between sites and sampling dates. The statistic analysis did not show significant spatial-temporal interactions. Malec6n, the most polluted site, showed the lowest recruit density and the greater presence of species considered as indicators of organic pollution, sedimentation and abrasion. The density of recruit species was higher in October 2007 and lower in May 2008, and it was apparently influenced by reproduction and cold front seasons, respectively. The higher dominance and abundance of S. siderea, S. radians and

  13. Differential response of two Mediterranean cold-water coral species to ocean acidification

    NASA Astrophysics Data System (ADS)

    Movilla, Juancho; Orejas, Covadonga; Calvo, Eva; Gori, Andrea; López-Sanz, Àngel; Grinyó, Jordi; Domínguez-Carrió, Carlos; Pelejero, Carles

    2014-09-01

    Cold-water coral (CWC) reefs constitute one of the most complex deep-sea habitats harboring a vast diversity of associated species. Like other tropical or temperate framework builders, these systems are facing an uncertain future due to several threats, such as global warming and ocean acidification. In the case of Mediterranean CWC communities, the effect may be exacerbated due to the greater capacity of these waters to absorb atmospheric CO2 compared to the global ocean. Calcification in these organisms is an energy-demanding process, and it is expected that energy requirements will be greater as seawater pH and the availability of carbonate ions decrease. Therefore, studies assessing the effect of a pH decrease in skeletal growth, and metabolic balance are critical to fully understand the potential responses of these organisms under a changing scenario. In this context, the present work aims to investigate the medium- to long-term effect of a low pH scenario on calcification and the biochemical composition of two CWCs from the Mediterranean, Dendrophyllia cornigera and Desmophyllum dianthus. After 314 d of exposure to acidified conditions, a significant decrease of 70 % was observed in Desmophyllum dianthus skeletal growth rate, while Dendrophyllia cornigera showed no differences between treatments. Instead, only subtle differences between treatments were observed in the organic matter amount, lipid content, skeletal microdensity, or porosity in both species, although due to the high variability of the results, these differences were not statistically significant. Our results also confirmed a heterogeneous effect of low pH on the skeletal growth rate of the organisms depending on their initial weight, suggesting that those specimens with high calcification rates may be the most susceptible to the negative effects of acidification.

  14. Validation of microsatellite multiplexes for parentage analysis and species discrimination in two hybridizing species of coral reef fish (Plectropomus spp., Serranidae)

    PubMed Central

    Harrison, Hugo B; Feldheim, Kevin A; Jones, Geoffrey P; Ma, Kayan; Mansour, Hicham; Perumal, Sadhasivam; Williamson, David H; Berumen, Michael L

    2014-01-01

    Microsatellites are often considered ideal markers to investigate ecological processes in animal populations. They are regularly used as genetic barcodes to identify species, individuals, and infer familial relationships. However, such applications are highly sensitive the number and diversity of microsatellite markers, which are also prone to error. Here, we propose a novel framework to assess the suitability of microsatellite datasets for parentage analysis and species discrimination in two closely related species of coral reef fish, Plectropomus leopardus and P. maculatus (Serranidae). Coral trout are important fisheries species throughout the Indo-Pacific region and have been shown to hybridize in parts of the Great Barrier Reef, Australia. We first describe the development of 25 microsatellite loci and their integration to three multiplex PCRs that co-amplify in both species. Using simulations, we demonstrate that the complete suite of markers provides appropriate power to discriminate between species, detect hybrid individuals, and resolve parent–offspring relationships in natural populations, with over 99.6% accuracy in parent–offspring assignments. The markers were also tested on seven additional species within the Plectropomus genus with polymorphism in 28–96% of loci. The multiplex PCRs developed here provide a reliable and cost-effective strategy to investigate evolutionary and ecological dynamics and will be broadly applicable in studies of wild populations and aquaculture brood stocks for these closely related fish species. PMID:25360247

  15. Validation of microsatellite multiplexes for parentage analysis and species discrimination in two hybridizing species of coral reef fish (Plectropomus spp., Serranidae).

    PubMed

    Harrison, Hugo B; Feldheim, Kevin A; Jones, Geoffrey P; Ma, Kayan; Mansour, Hicham; Perumal, Sadhasivam; Williamson, David H; Berumen, Michael L

    2014-06-01

    Microsatellites are often considered ideal markers to investigate ecological processes in animal populations. They are regularly used as genetic barcodes to identify species, individuals, and infer familial relationships. However, such applications are highly sensitive the number and diversity of microsatellite markers, which are also prone to error. Here, we propose a novel framework to assess the suitability of microsatellite datasets for parentage analysis and species discrimination in two closely related species of coral reef fish, Plectropomus leopardus and P. maculatus (Serranidae). Coral trout are important fisheries species throughout the Indo-Pacific region and have been shown to hybridize in parts of the Great Barrier Reef, Australia. We first describe the development of 25 microsatellite loci and their integration to three multiplex PCRs that co-amplify in both species. Using simulations, we demonstrate that the complete suite of markers provides appropriate power to discriminate between species, detect hybrid individuals, and resolve parent-offspring relationships in natural populations, with over 99.6% accuracy in parent-offspring assignments. The markers were also tested on seven additional species within the Plectropomus genus with polymorphism in 28-96% of loci. The multiplex PCRs developed here provide a reliable and cost-effective strategy to investigate evolutionary and ecological dynamics and will be broadly applicable in studies of wild populations and aquaculture brood stocks for these closely related fish species.

  16. Population Connectivity Measures of Fishery-Targeted Coral Reef Species to Inform Marine Reserve Network Design in Fiji

    PubMed Central

    Eastwood, Erin K.; López, Elora H.; Drew, Joshua A.

    2016-01-01

    Coral reef fish serve as food sources to coastal communities worldwide, yet are vulnerable to mounting anthropogenic pressures like overfishing and climate change. Marine reserve networks have become important tools for mitigating these pressures, and one of the most critical factors in determining their spatial design is the degree of connectivity among different populations of species prioritized for protection. To help inform the spatial design of an expanded reserve network in Fiji, we used rapidly evolving mitochondrial genes to investigate connectivity patterns of three coral reef species targeted by fisheries in Fiji: Epinephelus merra (Serranidae), Halichoeres trimaculatus (Labridae), and Holothuria atra (Holothuriidae). The two fish species, E. merra and Ha. trimaculatus, exhibited low genetic structuring and high amounts of gene flow, whereas the sea cucumber Ho. atra displayed high genetic partitioning and predominantly westward gene flow. The idiosyncratic patterns observed among these species indicate that patterns of connectivity in Fiji are likely determined by a combination of oceanographic and ecological characteristics. Our data indicate that in the cases of species with high connectivity, other factors such as representation or political availability may dictate where reserves are placed. In low connectivity species, ensuring upstream and downstream connections is critical. PMID:26805954

  17. Gene Expression Variation Resolves Species and Individual Strains among Coral-Associated Dinoflagellates within the Genus Symbiodinium

    PubMed Central

    Parkinson, John E.; Baumgarten, Sebastian; Michell, Craig T.; Baums, Iliana B.; LaJeunesse, Todd C.; Voolstra, Christian R.

    2016-01-01

    Reef-building corals depend on symbiotic mutualisms with photosynthetic dinoflagellates in the genus Symbiodinium. This large microalgal group comprises many highly divergent lineages (“Clades A–I”) and hundreds of undescribed species. Given their ecological importance, efforts have turned to genomic approaches to characterize the functional ecology of Symbiodinium. To date, investigators have only compared gene expression between representatives from separate clades—the equivalent of contrasting genera or families in other dinoflagellate groups—making it impossible to distinguish between clade-level and species-level functional differences. Here, we examined the transcriptomes of four species within one Symbiodinium clade (Clade B) at ∼20,000 orthologous genes, as well as multiple isoclonal cell lines within species (i.e., cultured strains). These species span two major adaptive radiations within Clade B, each encompassing both host-specialized and ecologically cryptic taxa. Species-specific expression differences were consistently enriched for photosynthesis-related genes, likely reflecting selection pressures driving niche diversification. Transcriptional variation among strains involved fatty acid metabolism and biosynthesis pathways. Such differences among individuals are potentially a major source of physiological variation, contributing to the functional diversity of coral holobionts composed of unique host–symbiont genotype pairings. Our findings expand the genomic resources available for this important symbiont group and emphasize the power of comparative transcriptomics as a method for studying speciation processes and interindividual variation in nonmodel organisms. PMID:26868597

  18. Population Connectivity Measures of Fishery-Targeted Coral Reef Species to Inform Marine Reserve Network Design in Fiji.

    PubMed

    Eastwood, Erin K; López, Elora H; Drew, Joshua A

    2016-01-25

    Coral reef fish serve as food sources to coastal communities worldwide, yet are vulnerable to mounting anthropogenic pressures like overfishing and climate change. Marine reserve networks have become important tools for mitigating these pressures, and one of the most critical factors in determining their spatial design is the degree of connectivity among different populations of species prioritized for protection. To help inform the spatial design of an expanded reserve network in Fiji, we used rapidly evolving mitochondrial genes to investigate connectivity patterns of three coral reef species targeted by fisheries in Fiji: Epinephelus merra (Serranidae), Halichoeres trimaculatus (Labridae), and Holothuria atra (Holothuriidae). The two fish species, E. merra and Ha. trimaculatus, exhibited low genetic structuring and high amounts of gene flow, whereas the sea cucumber Ho. atra displayed high genetic partitioning and predominantly westward gene flow. The idiosyncratic patterns observed among these species indicate that patterns of connectivity in Fiji are likely determined by a combination of oceanographic and ecological characteristics. Our data indicate that in the cases of species with high connectivity, other factors such as representation or political availability may dictate where reserves are placed. In low connectivity species, ensuring upstream and downstream connections is critical.

  19. Chronic and catastrophic natural mortality of three common Caribbean reef corals

    NASA Astrophysics Data System (ADS)

    Bythell, J. C.; Gladfelter, E. H.; Bythell, M.

    1993-11-01

    Compared to catastrophic impacts from storms, disease epidemics and bleaching events, little is known about the effects of more routine chronic mortality in reef corals. To monitor this ongoing mortality, monthly visual assessments of the cause of tissue damage were related to mortality rates (changes in planar surface area) of tagged colonies of three common reef corals: Montastrea annularis, Porites astreoides and Diploria strigosa at Buck Island Reef National Monument, St. Croix, US Virgin Islands. During the study Hurricane Hugo, the most powerful cyclone to affect the area in at least 60 y, made a direct impact on the site. Effects of the hurricane were extremely localized, with certain exposed sites being almost completely razed while others showed no detectable changes in community structure. Mortality caused both by the hurricane and by other factors during the 26 month study varied between species and also between site locations around the island. Differences in susceptibility were not dependent solely on gross morphology, because two robust, massive species showed opposite responses to hurricane damage and chronic mortality. Diploria strigosa was virtually unaffected by chronic factors, but was heavily damaged at exposed sites during the hurricane. In contrast, mortality from predation and tissue necrosis was high in Montastrea annularis, but it largely escaped damage from the hurricane because it was absent from the most severely scoured locations. Porites astreoides, with populations dominated by much smaller colonies, was affected by both chronic and hurricanerelated mortality. Differences in susceptibility to the various types of natural disturbance among species, coupled with high spatial and temporal variability in the effects of such disturbances, may be critical to the maintenance of species diversity on the reef.

  20. A new species of triadal coral snake of the genus Micrurus Wagler, 1824 (Serpentes: Elapidae) from northeastern Brazil.

    PubMed

    Pires, Matheus Godoy; Da Silva, Nelson Jorge; Feitosa, Darlan Tavares; Prudente, Ana Lúcia Da Costa; Filho, Gentil Alves Pereira; Zaher, Hussam

    2014-06-05

    The genus Micrurus comprises 123 currently recognized taxa (species and subspecies) that are traditionally arranged in four species groups diagnosable mainly by color pattern characteristics. Here, we describe a new species of triadal coral snake from northeastern Brazil. The new species is distinguished from other sympatric triadal congeners (M. lemniscatus carvalhoi, M. ibiboboca and M. brasiliensis) mainly by the entirely black parietals and by a suite of external characters and hemipenial morphology. The new species appears to be restricted to tropical ombrophilous lowland coastal forests of northeastern Brazil and all recently collected specimens are known to occur in small forest patches surrounded by periurban environment, which calls for an urgent evaluation on its conservation status.

  1. Pachyseris inattesa sp. n. (Cnidaria, Anthozoa, Scleractinia): a new reef coral species from the Red Sea and its phylogenetic relationships

    PubMed Central

    Terraneo, Tullia I.; Berumen, Michael L.; Arrigoni, Roberto; Waheed, Zarinah; Bouwmeester, Jessica; Caragnano, Annalisa; Stefani, Fabrizio; Benzoni, Francesca

    2014-01-01

    Abstract A new scleractinian coral species, Pachyseris inattesa sp. n., is described from the Red Sea. Despite a superficial resemblance with some species in the agariciid genus Leptoseris with which it has been previously confused, P. inattesa sp. n. has micro-morphological characters typical of the genus Pachyseris. This genus, once part of the Agariciidae, is comprised of five extant species and is widely distributed throughout the tropical Indo-Pacific. It is currently incertae sedis as a result of recent molecular analysis and appears to be closely related to the Euphylliidae. A molecular phylogenetic reconstruction including P. inattesa sp. n., the genus type species P. rugosa, and P. speciosa, all present in the Red Sea, was performed using the mitochondrial intergenic spacer between COI and 16S-rRNA. The results confirm that P. inattesa sp. n. is a monophyletic lineage closely related to the other Pachyseris species examined. PMID:25152672

  2. Can corals be harvested sustainably?

    PubMed

    Harriott, Vicki J

    2003-03-01

    The international trade in corals has been identified as a potential cause of localized depletion of coral populations in the major coral-exporting countries. The international coral trade is regulated by the Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES) agreement, which requires that export of corals is not detrimental to the species. The primary coral importing regions (USA and Europe) have threatened to limit or ban coral imports unless sustainable practices can be demonstrated. The spatial and temporal scale at which sustainability is defined is important in evaluating sustainability, e.g. at geological, regional or local scales. Other major issues are: the ecology of the target species; management options including provision of no-take areas; and the potential for coral culture. Implementation of practices that enhance ecological sustainability in the coral harvest fishery is possible, but may be difficult in some developing countries because of limited natural-resource management capacity.

  3. The Construction of a Coral Implantation Base and the Proof Experiment by Electrodeposition Method

    NASA Astrophysics Data System (ADS)

    Yoshitake, Masami; Nojima, Satoshi; Tokuyama, Hidekazu; Haraguchi, Satoru; Kadomoto, Yukio; Yoshida, Kazuo

    In recent years, we are facing a decline of coral reefs by bleaching and death of coral colonies, which is casued by rising of ocean temperatures presumably due to global warming and pollution due to human activity. It is our urgent issue to protect and reproduce coral reefs in a global scale. We propose an electrodeposition method using calcium and magnesium contained in natural seawater as a effective and way to revive coral reefs, because a product of electrodeposition characterized by porous texture provides suitable holes for implantation of coral larvae. We expect that the method creates a diverse coral reefs community similar to natural one comparing with other growth method. Since 2008, we have conducted coral growth experiments using electrodeposition in Yoronjima. As a result, Acropora sp., Porites sp. and Pocillopora sp. are observed, such as implantation of several types of coral larvae, and confirmed a growth of coral larvae.

  4. Temporal changes in the growth of two Mediterranean cold-water coral species, in situ and in aquaria

    NASA Astrophysics Data System (ADS)

    Lartaud, Franck; Pareige, Simon; de Rafelis, Marc; Feuillassier, Lionel; Bideau, Marjorie; Peru, Erwan; De la Vega, Elwyn; Nedoncelle, Karine; Romans, Pascal; Le Bris, Nadine

    2014-01-01

    In situ growth patterns of two-species of reef-building cold-water corals were investigated for the first time at different temporal scales, based on the redeployment of coral nubbins in their natural environment. Lophelia pertusa and Madrepora oculata were collected in November 2010 and May 2011 from the Lacaze-Duthiers canyon in the northwestern Mediterranean Sea (520 m depth). Three in situ growth experiments were performed from November 2010 to May 2011, May to September 2011 and November 2010 to September 2011. For comparison, aquaria experiments over comparable lengths of time were conducted with coral colonies collected in November 2010. In the canyon, new polyps from M. oculata and L. pertusa displayed similar growth rates in summer (5.8±3.8 and 7.3±1.7 mm yr-1 respectively), but M. oculata growed significantly slower during winter/spring than L. pertusa (4.1±1.8 and 8.4±2.7 mm yr-1 respectively). Budding rates however (the rate of new polyp addition per mother polyp per year) were similar between both species in winter/spring (45±40% for M. oculata and 48±72% for L. pertusa), but were significantly lower in summer for M. oculata (14±19%) compared to L. pertusa (58±94%). This seasonal difference in the growth between L. pertusa and M. oculata might reflect differences in species-specific physiology (such as reproduction) or feeding strategy, or a higher sensitivity of M. oculata to the variability of food supply in the Lacaze-Duthiers canyon resulting from periodic cascading events. The comparison of in situ and aquaria growth experiments showed no significant differences for budding and new polyp growth rates, which supports the validity of aquaria experiments for these kinds of investigations. However the budding rates observed were consistently lower in coral maintained in aquaria than those in in situ conditions, a finding which is to be considered when extrapolating laboratory based investigation results to the naturally occurring coral

  5. Internal carbonic anhydrase activity in the tissue of scleractinian corals is sufficient to support proposed roles in photosynthesis and calcification.

    PubMed

    Hopkinson, Brian M; Tansik, Anna L; Fitt, William K

    2015-07-01

    Reef-building corals import inorganic carbon (Ci) to build their calcium carbonate skeletons and to support photosynthesis by the symbiotic algae that reside in their tissue. The internal pathways that deliver Ci for both photosynthesis and calcification are known to involve the enzyme carbonic anhydrase (CA), which interconverts CO2 and HCO3 (-). We have developed a method for absolute quantification of internal CA (iCA) activity in coral tissue based on the rate of (18)O-removal from labeled Ci. The method was applied to three Caribbean corals (Orbicella faveolata, Porites astreoides and Siderastrea radians) and showed that these species have similar iCA activities per unit surface area, but that S. radians has ∼10-fold higher iCA activity per unit tissue volume. A model of coral Ci processing shows that the measured iCA activity is sufficient to support the proposed roles for iCA in Ci transport for photosynthesis and calcification. This is the case even when iCA activity is homogeneously distributed throughout the coral, but the model indicates that it would be advantageous to concentrate iCA in the spaces where calcification (the calcifying fluid) and photosynthesis (the oral endoderm) take place. We argue that because the rates of photosynthesis and calcification per unit surface area are similar among the corals studied here, the areal iCA activity used to deliver Ci for these reactions should also be similar. The elevated iCA activity per unit volume of S. radians compared with that of the other species is probably due to the thinner effective tissue thickness in this species.

  6. Benthic composition of a healthy subtropical reef: baseline species-level cover, with an emphasis on algae, in the Northwestern Hawaiian Islands.

    PubMed

    Vroom, Peter S; Braun, Cristi L

    2010-03-17

    The Northwestern Hawaiian Islands (NWHI) are considered to be among the most pristine coral reef ecosystems remaining on the planet. These reefs naturally contain a high percent cover of algal functional groups with relatively low coral abundance and exhibit thriving fish communities dominated by top predators. Despite their highly protected status, these reefs are at risk from both direct and indirect anthropogenic sources. This study provides the first comprehensive data on percent coverage of algae, coral, and non-coral invertebrates at the species level, and investigates spatial diversity patterns across the archipelago to document benthic communities before further environmental changes occur in response to global warming and ocean acidification. Monitoring studies show that non-calcified macroalgae cover a greater percentage of substrate than corals on many high latitude reef sites. Forereef habitats in atoll systems often contain high abundances of the green macroalga Microdictyon setchellianum and the brown macroalga Lobophora variegata, yet these organisms were uncommon in forereefs of non-atoll systems. Species of the brown macroalgal genera Padina, Sargassum, and Stypopodium and the red macroalgal genus Laurencia became increasingly common in the two northernmost atolls of the island chain but were uncommon components of more southerly islands. Conversely, the scleractinian coral Porites lobata was common on forereefs at southern islands but less common at northern islands. Currently accepted paradigms of what constitutes a "healthy" reef may not apply to the subtropical NWHI, and metrics used to gauge reef health (e.g., high coral cover) need to be reevaluated.

  7. In Situ Oxygen Dynamics in Coral-Algal Interactions

    PubMed Central

    Wangpraseurt, Daniel; Weber, Miriam; Røy, Hans; Polerecky, Lubos; de Beer, Dirk; Suharsono; Nugues, Maggy M.

    2012-01-01

    Background Coral reefs degrade globally at an alarming rate, with benthic algae often replacing corals. However, the extent to which benthic algae contribute to coral mortality, and the potential mechanisms involved, remain disputed. Recent laboratory studies suggested that algae kill corals by inducing hypoxia on the coral surface, through stimulated microbial respiration. Methods/Findings We examined the main premise of this hypothesis by measuring in situ oxygen microenvironments at the contact interface between the massive coral Porites spp. and turf algae, and between Porites spp. and crustose coralline algae (CCA). Oxygen levels at the interface were similar to healthy coral tissue and ranged between 300–400 µM during the day. At night, the interface was hypoxic (∼70 µM) in coral-turf interactions and close to anoxic (∼2 µM) in coral-CCA interactions, but these values were not significantly different from healthy tissue. The diffusive boundary layer (DBL) was about three times thicker at the interface than above healthy tissue, due to a depression in the local topography. A numerical model, developed to analyze the oxygen profiles above the irregular interface, revealed strongly reduced net photosynthesis and dark respiration rates at the coral-algal interface compared to unaffected tissue during the day and at night, respectively. Conclusions/Significance Our results showed that hypoxia was not a consistent feature in the microenvironment of the coral-algal interface under in situ conditions. Therefore, hypoxia alone is unlikely to be the cause of coral mortality. Due to the modified topography, the interaction zone is distinguished by a thicker diffusive boundary layer, which limits the local metabolic activity and likely promotes accumulation of potentially harmful metabolic products (e.g., allelochemicals and protons). Our study highlights the importance of mass transfer phenomena and the need for direct in situ measurements of microenvironmental

  8. Ecomorph or Endangered Coral? DNA and Microstructure Reveal Hawaiian Species Complexes: Montipora dilatata/flabellata/turgescens & M. patula/verrilli

    PubMed Central

    Forsman, Zac H.; Concepcion, Gregory T.; Haverkort, Roxanne D.; Shaw, Ross W.; Maragos, James E.; Toonen, Robert J.

    2010-01-01

    M. dilatata, M. flabellata, and M. patula and 80 other scleractinian corals were petitioned to be listed under the US Endangered Species Act (ESA), which would have major conservation implications. One of the difficulties with this evaluation is that reproductive boundaries between morphologically defined coral species are often permeable, and morphology can be wildly variable. We examined genetic and morphological variation in Hawaiian Montipora with a suite of molecular markers (mitochondrial: COI, CR, Cyt-B, 16S, ATP6; nuclear: ATPsβ, ITS) and microscopic skeletal measurements. Mitochondrial markers and the ITS region revealed four distinct clades: I) M. patula/M. verrilli, II) M. cf. incrassata, III) M. capitata, IV) M. dilatata/M. flabellata/M. cf. turgescens. These clades are likely to occur outside of Hawai'i according to mitochondrial control region haplotypes from previous studies. The ATPsβ intron data showed a pattern often interpreted as resulting from hybridization and introgression; however, incomplete lineage sorting may be more likely since the multicopy nuclear ITS region was consistent with the mitochondrial data. Furthermore, principal components analysis (PCA) of skeletal microstructure was concordant with the mitochondrial clades, while nominal taxa overlapped. The size and shape of verrucae or papillae contributed most to identifying groups, while colony-level morphology was highly variable. It is not yet clear if these species complexes represent population-level variation or incipient speciation (CA<1MYA), two alternatives that have very different conservation implications. This study highlights the difficulty in understanding the scale of genetic and morphological variation that corresponds to species as opposed to population-level variation, information that is essential for conservation and for understanding coral biodiversity. PMID:21151995

  9. Ecomorph or endangered coral? DNA and microstructure reveal hawaiian species complexes: Montipora dilatata/flabellata/turgescens & M. patula/verrilli.

    PubMed

    Forsman, Zac H; Concepcion, Gregory T; Haverkort, Roxanne D; Shaw, Ross W; Maragos, James E; Toonen, Robert J

    2010-12-02

    M. dilatata, M. flabellata, and M. patula and 80 other scleractinian corals were petitioned to be listed under the US Endangered Species Act (ESA), which would have major conservation implications. One of the difficulties with this evaluation is that reproductive boundaries between morphologically defined coral species are often permeable, and morphology can be wildly variable. We examined genetic and morphological variation in Hawaiian Montipora with a suite of molecular markers (mitochondrial: COI, CR, Cyt-B, 16S, ATP6; nuclear: ATPsβ, ITS) and microscopic skeletal measurements. Mitochondrial markers and the ITS region revealed four distinct clades: I) M. patula/M. verrilli, II) M. cf. incrassata, III) M. capitata, IV) M. dilatata/M. flabellata/M. cf. turgescens. These clades are likely to occur outside of Hawai'i according to mitochondrial control region haplotypes from previous studies. The ATPsβ intron data showed a pattern often interpreted as resulting from hybridization and introgression; however, incomplete lineage sorting may be more likely since the multicopy nuclear ITS region was consistent with the mitochondrial data. Furthermore, principal components analysis (PCA) of skeletal microstructure was concordant with the mitochondrial clades, while nominal taxa overlapped. The size and shape of verrucae or papillae contributed most to identifying groups, while colony-level morphology was highly variable. It is not yet clear if these species complexes represent population-level variation or incipient speciation (CA<1MYA), two alternatives that have very different conservation implications. This study highlights the difficulty in understanding the scale of genetic and morphological variation that corresponds to species as opposed to population-level variation, information that is essential for conservation and for understanding coral biodiversity.

  10. Mitotic index and size of symbiotic algae in Caribbean Reef corals

    NASA Astrophysics Data System (ADS)

    Wilkerson, F. P.; Kobayashi, D.; Muscatine, L.

    1988-05-01

    Size and frequency of division were determined for zooxanthellae from nine scleractinian coral species collected in February, 1983 at Discovery Bay, Jamaica, from four depths over a 51 m bathymetric range. Mean diameters of zooxanthellae ranged from 6.4 to 12.6 μm. Small zooxanthellae were found in Madracis mirabilis, Eusmilia fastigiata and Dendrogyra cylindrus whereas larger cells were seen in Agaricia agaricites, Porites astreoides, Montastrea cavernosa and Acropora cervicornis. Zooxanthellae division was not phased over a diel cycle. The percentage of zooxanthellae in a paired stage of cytokinesis (mitotic index or MI) was highly variable and ranged from 1.1% to 14.1%. Values measured in E. fastigiata and D. cylindrus were greater than in the other corals. MI was higher in branch tips of A. cervicornis than in branch bases. Daily average MI was negatively correlated with mean cell diameter and for a majority of the coral species increased with habitat depth. MI values were used to estimate specific growth rates and generation times for zooxanthellae in vivo for comparison with other dinoflagellates.

  11. Intra-skeletal calcite in a live-collected Porites sp.: Impact on environmental proxies and potential formation process

    NASA Astrophysics Data System (ADS)

    Lazareth, Claire E.; Soares-Pereira, Caroline; Douville, Eric; Brahmi, Chloé; Dissard, Delphine; Le Cornec, Florence; Thil, François; Gonzalez-Roubaud, Cécile; Caquineau, Sandrine; Cabioch, Guy

    2016-03-01

    Geochemical proxies measured in the carbonate skeleton of tropical coral Porites sp. have commonly been used to reconstruct sea surface temperature (SST) and more recently seawater pH. Nevertheless, both reconstructed SST and pH depend on the preservation state of the skeleton, here made of aragonite; i.e., diagenetic processes and its related effects should be limited. In this study, we report on the impact of the presence of intra-skeletal calcite on the skeleton geochemistry of a live-collected Porites sp. The Porites skeleton preservation state was analyzed using X-ray diffraction and scanning electron microscopy. Sr/Ca, Mg/Ca, U/Ca, Ba/Ca, Li/Mg, and B/Ca ratios were measured at a monthly and yearly resolution using quadrupole ICP-MS and multi-collector ICP-MS. The δ11B signatures and the calcite percentages were acquired at a yearly timescale. The coral colony presents two parts, one with less than 3% calcite (referred to as "no-calcite" skeleton), the other one, corresponding to the skeleton formed during the last 4 years of growth, with calcite percentages varying from 13% to 32% (referred to as "with calcite" skeleton). This intra-skeletal calcite replaces partly or completely numerous centers of calcification (COCs). All investigated geochemical tracers are significantly impacted by the presence of calcite. The reconstructed SST decreases by about 0.1 °C per calcite-percent as inferred from the Sr/Ca ratio. Such impact reaches up to 0.26 °C per calcite-percent for temperature deduced from the Li/Mg ratio. So, less than 5% of such intra-skeletal calcite does not prevent SST reconstructions using Sr/Ca ratio, but the percentage and type of calcite have to be determined before fine SST interpretation. Seawater pH reconstruction inferred from boron isotopes drop by about -0.011 pH-unit per calcite-percent. Such sensitivity to calcite presence is particularly dramatic for fine paleo-pH reconstructions. Here we suggest that after being brought to shallow

  12. Effects of offshore oil drilling on Philippine reef corals.

    USGS Publications Warehouse

    Hudson, J.H.; Shinn, E.A.; Robbin, D.M.

    1982-01-01

    An offshore drilling site in an area of extensive live-coral bottom off NW Palawan Island, Philippines, was examined 15 months after well completion. Porites lutea growth rates showed that little suppression of head coral growth could be attributed to drilling. Diver observation, however, together with analysis of sampling transect photomosaics, revealed 70-90% reduction in foliose, branching, and plate-like corals in an iron-stained area that extended out from the wellheads in a 115 X 85-m ellipse.-from Authors

  13. Two new species and a new record of Scale-worms (Polychaeta) from Southwest Atlantic deep-sea coral mounds .

    PubMed

    Miranda, Vinícius Da Rocha; Brasil, Ana Claudia Dos Santos

    2014-08-22

    Two new species of scale-worms, Harmothoe ruthae sp. nov. (Polynoidae) and Pholoides sinepapillatus sp. nov. (Sigalionidae) are described. In addition, we expand the description of Harmothoe gilchristi and extend its distribution to the Southwest Atlantic. The three species were found among the species of corals Lophelia pertusa, Solenosmilia variabilis, Enallopsammia rostrata, Madrepora oculata and Errina sp., a total of 257 samples of these corals were taken between 570 m and 1040 m depth, at the North-East coast of Rio de Janeiro, Brazil. 

  14. Characterisation of an atypical manifestation of black band disease on Porites lutea in the Western Indian Ocean

    PubMed Central

    Wilkinson, David A.; Schleyer, Michael H.; Chabanet, Pascale; Quod, Jean-Pascal; Tortosa, Pablo

    2016-01-01

    Recent surveys conducted on Reunion Island coral reefs revealed an atypical manifestation of black band disease on the main framework building coral, Porites lutea. This BBD manifestation (PorBBD) presented a thick lighter-colored band, which preceded the typical BBD lesion. Whilst BBD aetiology has been intensively described worldwide, it remains unclear if corals with apparently similar lesions across coral reefs are affected by the same pathogens. Therefore, a multidisciplinary approach involving field surveys, gross lesion monitoring, histopathology and 454-pyrosequencing was employed to provide the first comprehensive characterization of this particular manifestation. Surveys conducted within two geomorphological zones over two consecutive summers and winters showed spatial and seasonal patterns consistent with those found for typical BBD. Genetic analyses suggested an uncharacteristically high level of Vibrio spp. bacterial infection within PorBBD. However, microscopic analysis revealed high densities of cyanobacteria, penetrating the compromised tissue as well as the presence of basophilic bodies resembling bacterial aggregates in the living tissue, adjacent to the bacterial mat. Additionally, classical BBD-associated cyanobacterial strains, genetically related to Pseudoscillatoria coralii and Roseofilum reptotaenium were identified and isolated and the presence of sulfate-reducers or sulfide-oxidizers such as Desulfovibrio and Arcobacter, previously shown to be associated with anoxic microenvironment within typical BBD was also observed, confirming that PorBBD is a manifestation of classical BBD. PMID:27441106

  15. Incongruence between morphotypes and genetically delimited species in the coral genus Stylophora: phenotypic plasticity, morphological convergence, morphological stasis or interspecific hybridization?

    PubMed Central

    2011-01-01

    Background Morphological data suggest that, unlike most other groups of marine organisms, scleractinian corals of the genus Stylophora are more diverse in the western Indian Ocean and in the Red Sea than in the central Indo-Pacific. However, the morphology of corals is often a poor predictor of their actual biodiversity: hence, we conducted a genetic survey of Stylophora corals collected in Madagascar, Okinawa, the Philippines and New Caledonia in an attempt to find out the true number of species in these various locations. Results A molecular phylogenetic analysis of the mitochondrial ORF and putative control region concurs with a haploweb analysis of nuclear ITS2 sequences in delimiting three species among our dataset: species A and B are found in Madagascar whereas species C occurs in Okinawa, the Philippines and New Caledonia. Comparison of ITS1 sequences from these three species with data available online suggests that species C is also found on the Great Barrier Reef, in Malaysia, in the South China Sea and in Taiwan, and that a distinct species D occurs in the Red Sea. Shallow-water morphs of species A correspond to the morphological description of Stylophora madagascarensis, species B presents the morphology of Stylophora mordax, whereas species C comprises various morphotypes including Stylophora pistillata and Stylophora mordax. Conclusions Genetic analysis of the coral genus Stylophora reveals species boundaries that are not congruent with morphological traits. Of the four hypotheses that may explain such discrepancy (phenotypic plasticity, morphological stasis, morphological convergence, and interspecific hybridization), the first two appear likely to play a role but the fourth one is rejected since mitochondrial and nuclear markers yield congruent species delimitations. The position of the root in our molecular phylogenies suggests that the center of origin of Stylophora is located in the western Indian Ocean, which probably explains why this genus

  16. Recent origin and semi-permeable species boundaries in the scleractinian coral genus Stylophora from the Red Sea

    PubMed Central

    Arrigoni, Roberto; Benzoni, Francesca; Terraneo, Tullia I.; Caragnano, Annalisa; Berumen, Michael L.

    2016-01-01

    Reticulate evolution, introgressive hybridisation, and phenotypic plasticity have been documented in scleractinian corals and have challenged our ability to interpret speciation processes. Stylophora is a key model system in coral biology and physiology, but genetic analyses have revealed that cryptic lineages concealed by morphological stasis exist in the Stylophora pistillata species complex. The Red Sea represents a hotspot for Stylophora biodiversity with six morphospecies described, two of which are regionally endemic. We investigated Stylophora species boundaries from the Red Sea and the associated Symbiodinium by sequencing seven DNA loci. Stylophora morphospecies from the Red Sea were not resolved based on mitochondrial phylogenies and showed nuclear allele sharing. Low genetic differentiation, weak isolation, and strong gene flow were found among morphospecies although no signals of genetic recombination were evident among them. Stylophora mamillata harboured Symbiodinium clade C whereas the other two Stylophora morphospecies hosted either Symbiodinium clade A or C. These evolutionary patterns suggest that either gene exchange occurs through reticulate evolution or that multiple ecomorphs of a phenotypically plastic species occur in the Red Sea. The recent origin of the lineage leading to the Red Sea Stylophora may indicate an ongoing speciation driven by environmental changes and incomplete lineage sorting. PMID:27713475

  17. Allopatric divergence and speciation in coral reef fish: the three-spot dascyllus, Dascyllus trimaculatus, species complex.

    PubMed

    Leray, Matthieu; Beldade, Ricardo; Holbrook, Sally J; Schmitt, Russell J; Planes, Serge; Bernardi, Giacomo

    2010-05-01

    Long pelagic larval phases and the absence of physical barriers impede rapid speciation and contrast the high diversity observed in marine ecosystems such as coral reefs. In this study, we used the three-spot dascyllus (Dascyllus trimaculatus) species complex to evaluate speciation modes at the spatial scale of the Indo-Pacific. The complex includes four recognized species and four main color morphs that differ in distribution. Previous studies of the group using mitochondrial DNA revealed a noncongruence between color morphs and genetic groupings; with two of the color morphs grouped together and one color morph separated into three clades. Using extensive geographic sampling of 563 individuals and a combination of mitochondrial DNA sequences and 13 nuclear microsatellites, we defined population/species boundaries and inferred different speciation modes. The complex is composed of seven genetically distinct entities, some of which are distinct morphologically. Despite extensive dispersal abilities and an apparent lack of barriers, observed genetic partitions are consistent with allopatric speciation. However, ecological pressure, assortative mating, and sexual selection, were likely important during periods of geographical isolation. This study therefore suggests that primarily historical factors later followed by ecological factors caused divergence and speciation in this group of coral reef fish.

  18. Recent origin and semi-permeable species boundaries in the scleractinian coral genus Stylophora from the Red Sea.

    PubMed

    Arrigoni, Roberto; Benzoni, Francesca; Terraneo, Tullia I; Caragnano, Annalisa; Berumen, Michael L

    2016-10-07

    Reticulate evolution, introgressive hybridisation, and phenotypic plasticity have been documented in scleractinian corals and have challenged our ability to interpret speciation processes. Stylophora is a key model system in coral biology and physiology, but genetic analyses have revealed that cryptic lineages concealed by morphological stasis exist in the Stylophora pistillata species complex. The Red Sea represents a hotspot for Stylophora biodiversity with six morphospecies described, two of which are regionally endemic. We investigated Stylophora species boundaries from the Red Sea and the associated Symbiodinium by sequencing seven DNA loci. Stylophora morphospecies from the Red Sea were not resolved based on mitochondrial phylogenies and showed nuclear allele sharing. Low genetic differentiation, weak isolation, and strong gene flow were found among morphospecies although no signals of genetic recombination were evident among them. Stylophora mamillata harboured Symbiodinium clade C whereas the other two Stylophora morphospecies hosted either Symbiodinium clade A or C. These evolutionary patterns suggest that either gene exchange occurs through reticulate evolution or that multiple ecomorphs of a phenotypically plastic species occur in the Red Sea. The recent origin of the lineage leading to the Red Sea Stylophora may indicate an ongoing speciation driven by environmental changes and incomplete lineage sorting.

  19. Comparative Use of a Caribbean Mesophotic Coral Ecosystem and Association with Fish Spawning Aggregations by Three Species of Shark.

    PubMed

    Pickard, Alexandria E; Vaudo, Jeremy J; Wetherbee, Bradley M; Nemeth, Richard S; Blondeau, Jeremiah B; Kadison, Elizabeth A; Shivji, Mahmood S

    2016-01-01

    Understanding of species interactions within mesophotic coral ecosystems (MCEs; ~ 30-150 m) lags well behind that for shallow coral reefs. MCEs are often sites of fish spawning aggregations (FSAs) for a variety of species, including many groupers. Such reproductive fish aggregations represent temporal concentrations of potential prey that may be drivers of habitat use by predatory species, including sharks. We investigated movements of three species of sharks within a MCE and in relation to FSAs located on the shelf edge south of St. Thomas, United States Virgin Islands. Movements of 17 tiger (Galeocerdo cuvier), seven lemon (Negaprion brevirostris), and six Caribbean reef (Carcharhinus perezi) sharks tagged with acoustic transmitters were monitored within the MCE using an array of acoustic receivers spanning an area of 1,060 km2 over a five year period. Receivers were concentrated around prominent grouper FSAs to monitor movements of sharks in relation to these temporally transient aggregations. Over 130,000 detections of telemetered sharks were recorded, with four sharks tracked in excess of 3 years. All three shark species were present within the MCE over long periods of time and detected frequently at FSAs, but patterns of MCE use and orientation towards FSAs varied both spatially and temporally among species. Lemon sharks moved over a large expanse of the MCE, but concentrated their activities around FSAs during grouper spawning and were present within the MCE significantly more during grouper spawning season. Caribbean reef sharks were present within a restricted portion of the MCE for prolonged periods of time, but were also absent for long periods. Tiger sharks were detected throughout the extent of the acoustic array, with the MCE representing only portion of their habitat use, although a high degree of individual variation was observed. Our findings indicate that although patterns of use varied, all three species of sharks repeatedly utilized the MCE and

  20. Comparative Use of a Caribbean Mesophotic Coral Ecosystem and Association with Fish Spawning Aggregations by Three Species of Shark

    PubMed Central

    Pickard, Alexandria E.; Vaudo, Jeremy J.; Wetherbee, Bradley M.; Nemeth, Richard S.; Blondeau, Jeremiah B.; Kadison, Elizabeth A.; Shivji, Mahmood S.

    2016-01-01

    Understanding of species interactions within mesophotic coral ecosystems (MCEs; ~ 30–150 m) lags well behind that for shallow coral reefs. MCEs are often sites of fish spawning aggregations (FSAs) for a variety of species, including many groupers. Such reproductive fish aggregations represent temporal concentrations of potential prey that may be drivers of habitat use by predatory species, including sharks. We investigated movements of three species of sharks within a MCE and in relation to FSAs located on the shelf edge south of St. Thomas, United States Virgin Islands. Movements of 17 tiger (Galeocerdo cuvier), seven lemon (Negaprion brevirostris), and six Caribbean reef (Carcharhinus perezi) sharks tagged with acoustic transmitters were monitored within the MCE using an array of acoustic receivers spanning an area of 1,060 km2 over a five year period. Receivers were concentrated around prominent grouper FSAs to monitor movements of sharks in relation to these temporally transient aggregations. Over 130,000 detections of telemetered sharks were recorded, with four sharks tracked in excess of 3 years. All three shark species were present within the MCE over long periods of time and detected frequently at FSAs, but patterns of MCE use and orientation towards FSAs varied both spatially and temporally among species. Lemon sharks moved over a large expanse of the MCE, but concentrated their activities around FSAs during grouper spawning and were present within the MCE significantly more during grouper spawning season. Caribbean reef sharks were present within a restricted portion of the MCE for prolonged periods of time, but were also absent for long periods. Tiger sharks were detected throughout the extent of the acoustic array, with the MCE representing only portion of their habitat use, although a high degree of individual variation was observed. Our findings indicate that although patterns of use varied, all three species of sharks repeatedly utilized the MCE

  1. Success in Competition for Space in Two Invasive Coral Species in the western Atlantic – Tubastraea micranthus and T. coccinea

    PubMed Central

    Sammarco, Paul W.; Porter, Scott A.; Genazzio, Melissa; Sinclair, James

    2015-01-01

    Invasion success by an alien species is dependent upon rate of reproduction, growth, mortality, physical characteristics of the environment, and successful competition for resources with native species. For sessile, epibenthic marine species, one critical resource is space. We examined competitive success in two invasive Indo-Pacific corals involved in competition for space in the northern Gulf of Mexico—Tubastraea coccinea and T. micranthus—on up to 13 offshore oil/gas platforms south of the Mississippi River. Still-capture photos of thousands of overgrowth interactions between the target corals and other sessile epibenthic fauna were analyzed from ROV videos collected at 8–183 m depth. T. micranthus was observed overgrowing >90% of all sessile epibenthic species which it encountered. Frequencies of competitive success varied significantly between platforms. T. coccinea was competitively superior to all competitors pooled, at the 60% level. There was little variability between T. coccinea populations. T. coccinea encountered the following species most frequently—the encrusting sponges Xestospongia sp. (with the commensal Parazoanthus catenularis), X. carbonaria, Dictyonella funicularis, Mycale carmigropila, Phorbas amaranthus, and Haliclona vansoesti—and was found to be, on average, competitively superior to them. Both T. micranthus and T. coccinea appear to be good competitors for space against these species in the northern Gulf of Mexico. Competitive success in T. micranthus was highest in the NE part of the study area, and lowest in the SW area near the Mississippi River plume. T. coccinea’s competitive success peaked in the SW study area. This suggests that variation in competitive success both within and between populations of these species may be due to differences in local environmental factors. PMID:26684321

  2. Toxicity of Deepwater Horizon Source Oil and the Chemical Dispersant, Corexit® 9500, to Coral Larvae

    PubMed Central

    Goodbody-Gringley, Gretchen; Wetzel, Dana L.; Gillon, Daniel; Pulster, Erin; Miller, Allison; Ritchie, Kim B.

    2013-01-01

    Acute catastrophic events can cause significant damage to marine environments in a short time period and may have devastating long-term impacts. In April 2010 the BP-operated Deepwater Horizon (DWH) offshore oil rig exploded, releasing an estimated 760 million liters of crude oil into the Gulf of Mexico. This study examines the potential effects of oil spill exposure on coral larvae of the Florida Keys. Larvae of the brooding coral, Porites astreoides, and the broadcast spawning coral, Montastraea faveolata, were exposed to multiple concentrations of BP Horizon source oil (crude, weathered and WAF), oil in combination with the dispersant Corexit® 9500 (CEWAF), and dispersant alone, and analyzed for behavior, settlement, and survival. Settlement and survival of P. astreoides and M. faveolata larvae decreased with increasing concentrations of WAF, CEWAF and Corexit® 9500, however the degree of the response varied by species and solution. P. astreoides larvae experienced decreased settlement and survival following exposure to 0.62 ppm source oil, while M. faveolata larvae were negatively impacted by 0.65, 1.34 and 1.5 ppm, suggesting that P. astreoides larvae may be more tolerant to WAF exposure than M. faveolata larvae. Exposure to medium and high concentrations of CEWAF (4.28/18.56 and 30.99/35.76 ppm) and dispersant Corexit® 9500 (50 and 100 ppm), significantly decreased larval settlement and survival for both species. Furthermore, exposure to Corexit® 9500 resulted in settlement failure and complete larval mortality after exposure to 50 and 100 ppm for M. faveolata and 100 ppm for P. astreoides. These results indicate that exposure of coral larvae to oil spill related contaminants, particularly the dispersant Corexit® 9500, has the potential to negatively impact coral settlement and survival, thereby affecting the resilience and recovery of coral reefs following exposure to oil and dispersants. PMID:23326298

  3. A new gall crab species (Brachyura, Cryptochiridae) associated with the free-living coral Trachyphyllia geoffroyi (Scleractinia, Merulinidae)

    PubMed Central

    van der Meij, Sancia E.T.

    2015-01-01

    Abstract A new species of gall crab is described from the free-living stony coral Trachyphyllia geoffroyi. Specimens were collected during field work in Lembeh Strait (Indonesia) and off Kudat (Malaysian Borneo). This new species, here named Lithoscaptus semperi sp. n., is the ninth species assigned to the genus. It can be separated from its congeners by not having the internal orbital angle extending beyond the external orbital angle, and by the stout female P2 merus with prominent distomesial projection. In addition, the carapace surface appears smooth, despite having small tubercles on the anterior half, and is without noticeable spines, other than those on the frontal margin. The distinctive carapace pattern in life is a diagnostic character in male specimens. PMID:25987871

  4. Southern hemisphere deep-water stylasterid corals including a new species, Errinalabrosa sp. n. (Cnidaria, Hydrozoa, Stylasteridae), with notes on some symbiotic scalpellids (Cirripedia, Thoracica, Scalpellidae).

    PubMed

    Pica, Daniela; Cairns, Stephen D; Puce, Stefania; Newman, William A

    2015-01-01

    A number of stylasterid corals are known to act as host species and create refuges for a variety of mobile and sessile organisms, which enhances their habitat complexity. These include annelids, anthozoans, cirripeds, copepods, cyanobacteria, echinoderms, gastropods, hydroids and sponges. Here we report the first evidence of a diverse association between stylasterids and scalpellid pedunculate barnacles and describe a new stylasterid species, Errinalabrosa, from the Tristan da Cunha Archipelago. Overall, five stylasterid species are found to host eight scalpellid barnacles from several biogeographic regions in the southern hemisphere (Southern Ocean, temperate South America and the southern Indo-Pacific realms). There is an apparent lack of specificity in this kind of association and different grades of reaction to the symbiosis have been observed in the coral. These records suggest that the association between pedunculate barnacles and hard stylasterid corals has a wide distribution among different biogeographic realms and that it is relatively rare and confined largely to deep water.

  5. Southern hemisphere deep-water stylasterid corals including a new species, Errina labrosa sp. n. (Cnidaria, Hydrozoa, Stylasteridae), with notes on some symbiotic scalpellids (Cirripedia, Thoracica, Scalpellidae)

    PubMed Central

    Pica, Daniela; Cairns, Stephen D.; Puce, Stefania; Newman, William A.

    2015-01-01

    Abstract A number of stylasterid corals are known to act as host species and create refuges for a variety of mobile and sessile organisms, which enhances their habitat complexity. These include annelids, anthozoans, cirripeds, copepods, cyanobacteria, echinoderms, gastropods, hydroids and sponges. Here we report the first evidence of a diverse association between stylasterids and scalpellid pedunculate barnacles and describe a new stylasterid species, Errina labrosa, from the Tristan da Cunha Archipelago. Overall, five stylasterid species are found to host eight scalpellid barnacles from several biogeographic regions in the southern hemisphere (Southern Ocean, temperate South America and the southern Indo-Pacific realms). There is an apparent lack of specificity in this kind of association and different grades of reaction to the symbiosis have been observed in the coral. These records suggest that the association between pedunculate barnacles and hard stylasterid corals has a wide distribution among different biogeographic realms and that it is relatively rare and confined largely to deep water. PMID:25632246

  6. Effects of frequent fish predation on corals in Hawaii

    NASA Astrophysics Data System (ADS)

    Jayewardene, D.; Donahue, M. J.; Birkeland, C.

    2009-06-01

    The abundance of lesions from fish bites on corals was quantified at nine shallow reefs in the main Hawaiian Islands. There were on average 117 bite scars m-2 on Pocillopora meandrina tissue from the barred filefish Cantherhines dumerilii, 69 bites m-2 on Porites compressa tissue, and 4 bites m-2 on Porites lobata tissue from the spotted puffer Arothron meleagris. Across sites, the frequency of A. meleagris bites on P. compressa per unit area of living coral cover declined exponentially with increasing coral cover. P. compressa nubbins in two size classes (1-2 cm and 4-5 cm) were transplanted onto six study reefs. Nubbins in the small size class were entirely removed by bites from A. meleagris, while nubbins ≥4 cm were only partially consumed, leaving them able to recover. At sites with abundant P. compressa, predation had little effect on transplanted nubbins; at sites where P. compressa comprised less than 5% of living cover, all nubbins were preyed upon. A. meleagris bite lesions on P. compressa were monitored through time and fully recovered in 42 ± 4 days. A model of the risk of over-predation (a second predation event before the first is healed) decreased exponentially with increasing coral cover and increased linearly with increasing lesion healing time. The increased risk of over-predation at low coral cover could indicate an Allee effect limiting the recovery of coral populations if coral cover is substantially reduced by natural or anthropogenic disturbances.

  7. Growing coral larger and faster: micro-colony-fusion as a strategy for accelerating coral cover.

    PubMed

    Forsman, Zac H; Page, Christopher A; Toonen, Robert J; Vaughan, David

    2015-01-01

    Fusion is an important life history strategy for clonal organisms to increase access to shared resources, to compete for space, and to recover from disturbance. For reef building corals, fragmentation and colony fusion are key components of resilience to disturbance. Observations of small fragments spreading tissue and fusing over artificial substrates prompted experiments aimed at further characterizing Atlantic and Pacific corals under various conditions. Small (∼1-3 cm(2)) fragments from the same colony spaced regularly over ceramic tiles resulted in spreading at rapid rates (e.g., tens of square centimeters per month) followed by isogenic fusion. Using this strategy, we demonstrate growth, in terms of area encrusted and covered by living tissue, of Orbicella faveolata, Pseudodiploria clivosa, and Porites lobata as high as 63, 48, and 23 cm(2) per month respectively. We found a relationship between starting and ending size of fragments, with larger fragments growing at a faster rate. Porites lobata showed significant tank effects on rates of tissue spreading indicating sensitivity to biotic and abiotic factors. The tendency of small coral fragments to encrust and fuse over a variety of surfaces can be exploited for a variety of applications such as coral cultivation, assays for coral growth, and reef restoration.

  8. Growing coral larger and faster: micro-colony-fusion as a strategy for accelerating coral cover

    PubMed Central

    Page, Christopher A.; Toonen, Robert J.; Vaughan, David

    2015-01-01

    Fusion is an important life history strategy for clonal organisms to increase access to shared resources, to compete for space, and to recover from disturbance. For reef building corals, fragmentation and colony fusion are key components of resilience to disturbance. Observations of small fragments spreading tissue and fusing over artificial substrates prompted experiments aimed at further characterizing Atlantic and Pacific corals under various conditions. Small (∼1–3 cm2) fragments from the same colony spaced regularly over ceramic tiles resulted in spreading at rapid rates (e.g., tens of square centimeters per month) followed by isogenic fusion. Using this strategy, we demonstrate growth, in terms of area encrusted and covered by living tissue, of Orbicella faveolata, Pseudodiploria clivosa, and Porites lobata as high as 63, 48, and 23 cm2 per month respectively. We found a relationship between starting and ending size of fragments, with larger fragments growing at a faster rate. Porites lobata showed significant tank effects on rates of tissue spreading indicating sensitivity to biotic and abiotic factors. The tendency of small coral fragments to encrust and fuse over a variety of surfaces can be exploited for a variety of applications such as coral cultivation, assays for coral growth, and reef restoration. PMID:26500822

  9. Detection of polyketide synthase and nonribosomal peptide synthetase biosynthetic genes from antimicrobial coral-associated actinomycetes.

    PubMed

    Li, Jie; Dong, Jun-De; Yang, Jian; Luo, Xiong-Ming; Zhang, Si

    2014-10-01

    The diversity and properties of actinobacteria, predominant residents in coral holobionts, have been rarely documented. In this study, we aimed to explore the species diversity, antimicrobial activities and biosynthetic potential of culturable actinomycetes within the tissues of the scleractinian corals Porites lutea, Galaxea fascicularis and Acropora millepora from the South China Sea. A total of 70 strains representing 13 families and 15 genera of actinobacteria were isolated. The antimicrobial activity and biosynthetic potential of fifteen representative filamentous actinomycetes were estimated. Crude fermentation extracts of 6 strains exhibited comparable or greater activities against Vibrio alginolyticus than ciprofloxacin. Seven of the 15 actinomycetes strains possess type I polyketide synthases (PKS-I) and/or nonribosomal peptide synthetases (NRPS) genes. Nine tested strains possess type II polyketide synthases (PKS-II). Phylogenetic analysis based on 16S rRNA gene sequences indicated that these PKS and NRPS gene screening positive strains belong to genera Nocardiopsis, Pseudonocardia, Streptomyces, Micromonospora, Amycolatopsis and Prauserella. One PKS-I and four NRPS fragments showed <70% similarity to their closest relatives, which suggested the novelty of these genes. This study helps uncover the genetic capacity of stony coral-associated actinomycetes to produce bioactive molecules.

  10. Do the shuffle: Changes in Symbiodinium consortia throughout juvenile coral development.

    PubMed

    Reich, Hannah G; Robertson, Deborah L; Goodbody-Gringley, Gretchen

    2017-01-01

    Previous studies of symbiotic associations between scleractinians corals and Symbiodinium have demonstrated that the consortium of symbionts can change in response to environmental conditions. However, less is known about symbiont shuffling during early coral development, particularly in brooding species. This study examined whether Symbiodinium consortia (1) varied in Porites astreoides on shallow (10m) and upper mesophotic (30m) reefs, (2) changed during coral development, and (3) influenced growth of juveniles in different environments. Symbiodinium ITS2 sequences were amplified using universal primers and analyzed using phylotype-specific primers designed for phylotypes A, B, and C. Adults from both depths were found to host only phylotype A, phylotypes A and B, or phylotypes A, B, and C and the frequency of the phylotype composition did not vary with depth. However, phylotype A was the dominant symbiont that was vertically transmitted to the planulae. The presence of phylotypes B and C was detected in the majority of juveniles when transplanted onto the shallow and upper mesophotic reefs whereas only phylotype A was detected in the majority of juveniles reared in outdoor aquaria. In addition, growth of juvenile P. astreoides harboring different combinations of Symbiodinium phylotypes did not vary when transplanted to different reef zones. However, juveniles reared in in situ reef environments grew faster than those reared in ex situ outdoor aquaria. These results show that Symbiodinium consortia change during development of P. astreoides and are influenced by environmental conditions.

  11. Do the shuffle: Changes in Symbiodinium consortia throughout juvenile coral development

    PubMed Central

    Reich, Hannah G.; Robertson, Deborah L.; Goodbody-Gringley, Gretchen

    2017-01-01

    Previous studies of symbiotic associations between scleractinians corals and Symbiodinium have demonstrated that the consortium of symbionts can change in response to environmental conditions. However, less is known about symbiont shuffling during early coral development, particularly in brooding species. This study examined whether Symbiodinium consortia (1) varied in Porites astreoides on shallow (10m) and upper mesophotic (30m) reefs, (2) changed during coral development, and (3) influenced growth of juveniles in different environments. Symbiodinium ITS2 sequences were amplified using universal primers and analyzed using phylotype-specific primers designed for phylotypes A, B, and C. Adults from both depths were found to host only phylotype A, phylotypes A and B, or phylotypes A, B, and C and the frequency of the phylotype composition did not vary with depth. However, phylotype A was the dominant symbiont that was vertically transmitted to the planulae. The presence of phylotypes B and C was detected in the majority of juveniles when transplanted onto the shallow and upper mesophotic reefs whereas only phylotype A was detected in the majority of juveniles reared in outdoor aquaria. In addition, growth of juvenile P. astreoides harboring different combinations of Symbiodinium phylotypes did not vary when transplanted to different reef zones. However, juveniles reared in in situ reef environments grew faster than those reared in ex situ outdoor aquaria. These results show that Symbiodinium consortia change during development of P. astreoides and are influenced by environmental conditions. PMID:28182684

  12. Severe impact and subsequent recovery of a coral assemblage following the 1997-8 El Niño event: a 17-year study from Bahia, Brazil.

    PubMed

    Kelmo, Francisco; Attrill, Martin J

    2013-01-01

    The coral reefs of northern Bahia evolved in isolation from other Atlantic systems and under conditions of high environmental stress, particularly high turbidity. We have monitored the scleractinian assemblage of four shallow bank reefs (Praia do Forte, Itacimirim, Guarajuba and Abai) annually for 17 years since 1995, collecting quantitative data on diversity and density of coral colonies. As the sampling period included the 1997-8 El Niño event, the most severe on record, for the first time these results allow a quantitative assessment of the long-term impact of this major environmental stressor on such a coral assemblage. After El Niño, most species showed significantly reduced densities of colonies, this decline occurring for the subsequent two years without evidence of any new settlement until 2001. From 2000 to 2007 the species Porites astreoides went unrecorded. Recovery was slow, and multivariate analysis revealed that assemblages had not returned to the pre-El Niño state until 2011. It therefore took 13 years for full recovery of the coral assemblage to occur, which has consequences for reef systems if such El-Niño events become more frequent in the future.

  13. Severe Impact and Subsequent Recovery of a Coral Assemblage following the 1997–8 El Niño Event: A 17-Year Study from Bahia, Brazil

    PubMed Central

    Kelmo, Francisco; Attrill, Martin J.

    2013-01-01

    The coral reefs of northern Bahia evolved in isolation from other Atlantic systems and under conditions of high environmental stress, particularly high turbidity. We have monitored the scleractinian assemblage of four shallow bank reefs (Praia do Forte, Itacimirim, Guarajuba and Abai) annually for 17 years since 1995, collecting quantitative data on diversity and density of coral colonies. As the sampling period included the 1997–8 El Niño event, the most severe on record, for the first time these results allow a quantitative assessment of the long-term impact of this major environmental stressor on such a coral assemblage. After El Niño, most species showed significantly reduced densities of colonies, this decline occurring for the subsequent two years without evidence of any new settlement until 2001. From 2000 to 2007 the species Porites astreoides went unrecorded. Recovery was slow, and multivariate analysis revealed that assemblages had not returned to the pre-El Niño state until 2011. It therefore took 13 years for full recovery of the coral assemblage to occur, which has consequences for reef systems if such El-Niño events become more frequent in the future. PMID:23741459

  14. Multi-species Coral Sr/Ca-Based Sea-Surface Temperature Reconstruction Using Orbicella faveolata and Siderastrea siderea from Dry Tortugas National Park, FL

    NASA Astrophysics Data System (ADS)

    Flannery, J. A.; Richey, J. N.; Thirumalai, K.; Poore, R. Z.

    2015-12-01

    Massive coral skeletons provide an important geologic archive of climate information over the past several centuries, due to their annual banding patterns and longevity. The ratio of strontium to calcium (Sr/Ca) in coral skeletons is dependent on the temperature of the seawater at the time of growth and, therefore, provides a powerful proxy of historic sea-surface temperature (SST). This study used cores from two modern coral colonies—Orbicella faveolata (formerly Montastraea faveolata) and Siderastrea siderea—collected from the Dry Tortugas National Park, Florida (DRTO), located in the southern Gulf of Mexico. The corals were subsampled at monthly resolution and Sr/Ca determinations were made using ICP-OES. Sr/Ca was calibrated to SST using previously-published calibration equations specific to each species. Both the O. faveolata (1893-2008) and S. siderea (1837-2012) records have well-defined annual cycles of Sr/Ca, which suggest a seasonal SST range of ~10-15°C: a range consistent with in situ instrumental SST records from DRTO. Our reconstructions of mean annual Sr/Ca-based SST and Sr/Ca variability from the two coral species show similar multi-decadal trends and strong coherency through overlapping time intervals. We investigated the intervals of divergence among the three independent DRTO records (two different species), and found that sudden drops in linear extension in S. siderea likely skewed the mean annual temperature record. This result underscores the importance of using multiple-coral geochemical records when reconstructing regional climate. A stacked record of SST derived from the three different coral colonies growing at DRTO from 1837-2008 showed a distinct trend toward cooler mean annual Sr/Ca-based SST from the late 1950s to the late 1960s, which coincides with a cooling trend found in several other Northern Hemisphere temperature reconstructions, and is likely linked to variability of the Atlantic Multi-decadal Oscillation.

  15. Coral Sr-U thermometry

    NASA Astrophysics Data System (ADS)

    DeCarlo, Thomas M.; Gaetani, Glenn A.; Cohen, Anne L.; Foster, Gavin L.; Alpert, Alice E.; Stewart, Joseph A.

    2016-06-01

    Coral skeletons archive past climate variability with unrivaled temporal resolution. However, extraction of accurate temperature information from coral skeletons has been limited by "vital effects," which confound, and sometimes override, the temperature dependence of geochemical proxies. We present a new approach to coral paleothermometry based on results of abiogenic precipitation experiments interpreted within a framework provided by a quantitative model of the coral biomineralization process. DeCarlo et al. (2015a) investigated temperature and carbonate chemistry controls on abiogenic partitioning of Sr/Ca and U/Ca between aragonite and seawater and modeled the sensitivity of skeletal composition to processes occurring at the site of calcification. The model predicts that temperature can be accurately reconstructed from coral skeleton by combining Sr/Ca and U/Ca ratios into a new proxy, which we refer to hereafter as the Sr-U thermometer. Here we test the model predictions with measured Sr/Ca and U/Ca ratios of 14 Porites sp. corals collected from the tropical Pacific Ocean and the Red Sea, with a subset also analyzed using the boron isotope (δ11B) pH proxy. Observed relationships among Sr/Ca, U/Ca, and δ11B agree with model predictions, indicating that the model accounts for the key features of the coral biomineralization process. By calibrating to instrumental temperature records, we show that Sr-U captures 93% of mean annual temperature variability (26-30°C) and has a standard deviation of prediction of 0.5°C, compared to 1°C using Sr/Ca alone. The Sr-U thermometer may offer significantly improved reliability for reconstructing past ocean temperatures from coral skeletons.

  16. Ornamental Marine Species Culture in the Coral Triangle: Seahorse Demonstration Project in the Spermonde Islands, Sulawesi, Indonesia

    NASA Astrophysics Data System (ADS)

    Williams, Susan L.; Janetski, Noel; Abbott, Jessica; Blankenhorn, Sven; Cheng, Brian; Crafton, R. Eliot; Hameed, Sarah O.; Rapi, Saipul; Trockel, Dale

    2014-12-01

    Ornamental marine species (`OMS') provide valuable income for developing nations in the Indo-Pacific Coral Triangle, from which most of the specimens are exported. OMS culture can help diversify livelihoods in the region, in support of management and conservation efforts to reduce destructive fishing and collection practices that threaten coral reef and seagrass ecosystems. Adoption of OMS culture depends on demonstrating its success as a livelihood, yet few studies of OMS culture exist in the region. We present a case study of a land-based culture project for an endangered seahorse ( Hippocampus barbouri) in the Spermonde Islands, Sulawesi, Indonesia. The business model demonstrated that culturing can increase family income by seven times. A Strengths Weaknesses Opportunities Threats (SWOT) analysis indicated good collaboration among diverse stakeholders and opportunities for culturing non-endangered species and for offshoot projects, but complicated permitting was an issue as were threats of market flooding and production declines. The OMS international market is strong, Indonesian exporters expressed great interest in cultured product, and Indonesia is the largest exporting country for H. barbouri. Yet, a comparison of Indonesia ornamental marine fish exports to fish abundance in a single local market indicated that OMS culture cannot replace fishing livelihoods. Nevertheless, seahorse and other OMS culture can play a role in management and conservation by supplementing and diversifying the fishing and collecting livelihoods in the developing nations that provide the majority of the global OMS.

  17. Ornamental marine species culture in the coral triangle: seahorse demonstration project in the Spermonde Islands, Sulawesi, Indonesia.

    PubMed

    Williams, Susan L; Janetski, Noel; Abbott, Jessica; Blankenhorn, Sven; Cheng, Brian; Crafton, R Eliot; Hameed, Sarah O; Rapi, Saipul; Trockel, Dale

    2014-12-01

    Ornamental marine species ('OMS') provide valuable income for developing nations in the Indo-Pacific Coral Triangle, from which most of the specimens are exported. OMS culture can help diversify livelihoods in the region, in support of management and conservation efforts to reduce destructive fishing and collection practices that threaten coral reef and seagrass ecosystems. Adoption of OMS culture depends on demonstrating its success as a livelihood, yet few studies of OMS culture exist in the region. We present a case study of a land-based culture project for an endangered seahorse (Hippocampus barbouri) in the Spermonde Islands, Sulawesi, Indonesia. The business model demonstrated that culturing can increase family income by seven times. A Strengths Weaknesses Opportunities Threats (SWOT) analysis indicated good collaboration among diverse stakeholders and opportunities for culturing non-endangered species and for offshoot projects, but complicated permitting was an issue as were threats of market flooding and production declines. The OMS international market is strong, Indonesian exporters expressed great interest in cultured product, and Indonesia is the largest exporting country for H. barbouri. Yet, a comparison of Indonesia ornamental marine fish exports to fish abundance in a single local market indicated that OMS culture cannot replace fishing livelihoods. Nevertheless, seahorse and other OMS culture can play a role in management and conservation by supplementing and diversifying the fishing and collecting livelihoods in the developing nations that provide the majority of the global OMS.

  18. Comparison of archaeal and bacterial communities in two sponge species and seawater from an Indonesian coral reef environment.

    PubMed

    Polónia, Ana Rita Moura; Cleary, Daniel Francis Richard; Freitas, Rossana; Coelho, Francisco José Riso da Costa; de Voogd, Nicole Joy; Gomes, Newton Carlos Marcial

    2016-10-01

    Most existing coral reef studies have focused on a single biotope and a single domain (Archaea or Bacteria). Few coral reef studies have explored the archaeal and bacterial community simultaneously. In this study, we compare the diversity and composition of archaeal and bacterial communities in seawater and two closely related sponge species (Stylissa carteri and Stylissa massa) in the Berau reef system, Indonesia. A 16S rRNA gene barcoded pyrosequencing approach was used to test to what extent seawater, S. carteri and S. massa host compositionally distinct communities of Archaea and Bacteria. Proteobacteria dominated the bacterial communities of all three studied biotopes whereas Euryarchaeota was the most abundant archaeal phylum in seawater and Crenarchaeota the most abundant archaeal phylum in both Stylissa species. Biotopes explained 56% and 53% of the variation in archaeal and bacterial composition respectively and there was significant congruence between the composition of archaeal and bacterial communities. These results suggest that the processes that drive bacterial composition within the studied biotopes may be fundamentally similar to those that drive archaeal composition.

  19. Community change and evidence for variable warm-water temperature adaptation of corals in Northern Male Atoll, Maldives.

    PubMed

    McClanahan, T R; Muthiga, N A

    2014-03-15

    This study provides a descriptive analysis of the North Male, Maldives seven years after the 1998 bleaching disturbance to determine the state of the coral community composition, the recruitment community, evidence for recovery, and adaptation to thermal stress. Overall, hard coral cover recovered at a rate commonly reported in the literature but with high spatial variability and shifts in taxonomic composition. Massive Porites, Pavona, Synarea, and Goniopora were unusually common in both the recruit and adult communities. Coral recruitment was low and some coral taxa, namely Tubipora, Seriatopora, and Stylophora, were rarer than expected. A study of the bleaching response to a thermal anomaly in 2005 indicated that some taxa, including Leptoria, Platygyra, Favites, Fungia, Hydnophora, and Galaxea astreata, bleached as predicted while others, including Acropora, Pocillopora, branching Porites, Montipora, Stylophora, and Alveopora, bleached less than predicted. This indicates variable-adaptation potentials among the taxa and considerable potential for ecological reorganization of the coral community.

  20. Scleractinian corals cultured in low Mg/Ca seawater form aragonite skeleton

    NASA Astrophysics Data System (ADS)

    Stolarski, Jaroslaw; Reynaud, Stéphanie; Ferrier-Pages, Christine; Janiszewska, Katarzyna; Domart-Coulon, Isabelle; Beraud, Eric; Marrocchi, Yves; Mazur, Maciej; Szlachetko, Jakub; Meibom, Anders

    2010-05-01

    concentration or by increasing the Ca concentration. In our experiments, we did both. Before the corals were exposed to low Mg/Ca ASW conditions, they were labeled with 86Sr for 3 days, following procedures described in Houlbreque et al. (GRL 2009: doi:10.1029/2008GL036782), in order to precisely define the skeletal growth front at the start of the experiment. 86Sr labeled corals were transferred to aquaria with ASW with Mg/Ca = 2. In the experiment in which a low Mg/Ca ratio was obtained by lowering the Mg concentration, the corals immediately died, presumably because Mg is an element required in metabolism. In the experiment in which the low Mg/Ca ratio was obtained by increasing the Ca concentration, the corals appeared unstressed (tentacles extended) and they were kept alive for 30 days. Subsequent NanoSIMS imaging showed that the 86Sr-labelled growth front in Porites, Pavona, and Galaxea had been overgrown by a ca. 10-20 μm newly formed skeleton. The 86Sr label was not incorporated into Acropora specimens, most likely because skeleton formation had ceased during handling, perhaps because of stress or sickness in this species. Micro-raman mapping demonstrated an exclusively aragonitic mineralogy of the skeleton formed in the low Mg/Ca ASW. This indicates that scleractinian corals form their skeleton under a biologically control that renders the skeletal mineralogy insensitive to even large variations in the Mg/Ca ratio of the ambient seawater. Additional experimental observations, not mentioned here due to length limitations, will be presented at the meeting.

  1. Two new species of the genus Anisomysis (Anisomysis) (Crustacea, Mysida, Mysidae) from coral reef waters in Thailand.

    PubMed

    Moriya, Mitsuyasu; Srinui, Khwanruan; Sawamoto, Shozo

    2015-01-01

    Two new species of Anisomysis Hansen, 1910 (Mysida, Mysidae), Anisomysis (Anisomysis) spinaintus sp. n. and Anisomysis (Anisomysis) phuketensis sp. n., from coral-reef waters in Thailand are described. Anisomysis (Anisomysis) spinaintus, collected in the Chaolao Beach, Chanthaburi Province, is distinguished from the closely allied species Anisomysis (Anisomysis) incisa Tattersall, 1936, and Anisomysis (Anisomysis) hawaiiensis Murano, 1995, by the presence of 6-9 spines on the apical cleft of telson, which are absent in the latter two allied species. The new species can also be distinguished from Anisomysis (Anisomysis) aikawai Ii, 1964, by the presence of a deep telson cleft and a large number of spines on the lateral margin of telson. Anisomysis (Anisomysis) phuketensis sp. n., collected in Ko Lon, Phuket, is distinguished from the allied species Anisomysis (Anisomysis) robustispina Panampunnayil, 1984, by having a short telson and a pair of long spines on the apical part of the telson. Keys to the subgenera and species of Anisomysis, including the two new species, are presented.

  2. Draft Genome Sequence of a Novel Luteimonas sp. Strain from Coral Mucus, Hawai‘i

    PubMed Central

    Miller, James M.; Rowley, Sonia J.

    2016-01-01

    Luteimonas sp. strain JM171 was cultivated from mucus collected around the coral Porites lobata. The JM171 draft genome of 2,992,353 bp contains 2,672 protein-coding open reading frames, 45 tRNA coding regions, and encodes a putative globin-coupled diguanylate cyclase, JmGReg. PMID:27811107

  3. A sea water barrier to coral gene flow.

    PubMed

    Lessios, H A

    2012-11-01

    Land is not the only barrier to dispersal encountered by marine organisms. For sedentary shallow water species, there is an additional, marine barrier, 5000 km of uninterrupted deep-water stretch between the central and the eastern Pacific. This expanse of water, known as the ‘Eastern Pacific Barrier’, has been separating faunas of the two oceanic regions since the beginning of the Cenozoic. Species with larvae that cannot stay in the plankton for the time it takes to cross between the two sides have been evolving independently. That the eastern Pacific does not share species with the rest of the Pacific was obvious to naturalists two centuries ago (Darwin 1860). Yet, this rule has exceptions. A small minority of species are known to straddle the Eastern Pacific Barrier. One such exception is the scleractinian coral Porites lobata (Fig. 1). This species is spread widely throughout the Indo-Pacific, where it is one of the major reef-builders, but it is also encountered in the eastern Pacific. Are eastern and central Pacific populations of this coral connected by gene flow? In this issue of Molecular Ecology, Baums et al. (2012) use microsatellite data to answer this question. They show that P. lobata populations in the eastern Pacific are cut off from genetic influx from the rest of the Pacific. Populations within each of the two oceanic regions are genetically connected (though those in the Hawaiian islands are also isolated). Significantly, the population in the Clipperton Atoll, the westernmost island in the eastern Pacific, genetically groups with populations from the central Pacific, suggesting that crossing the Eastern Pacific Barrier by P. lobata propagules does occasionally occur.

  4. Colony-specific investigations reveal highly variable responses among individual corals to ocean acidification and warming.

    PubMed

    Kavousi, Javid; Reimer, James Davis; Tanaka, Yasuaki; Nakamura, Takashi

    2015-08-01

    As anthropogenic climate change is an ongoing concern, scientific investigations on its impacts on coral reefs are increasing. Although impacts of combined ocean acidification (OA) and temperature stress (T) on reef-building scleractinian corals have been studied at the genus, species and population levels, there are little data available on how individual corals respond to combined OA and anomalous temperatures. In this study, we exposed individual colonies of Acropora digitifera, Montipora digitata and Porites cylindrica to four pCO2-temperature treatments including 400 μatm-28 °C, 400 μatm-31 °C, 1000 μatm-28 °C and 1000 μatm-31 °C for 26 days. Physiological parameters including calcification, protein content, maximum photosynthetic efficiency, Symbiodinium density, and chlorophyll content along with Symbiodinium type of each colony were examined. Along with intercolonial responses, responses of individual colonies versus pooled data to the treatments were investigated. The main results were: 1) responses to either OA or T or their combination were different between individual colonies when considering physiological functions; 2) tolerance to either OA or T was not synonymous with tolerance to the other parameter; 3) tolerance to both OA and T did not necessarily lead to tolerance of OA and T combined (OAT) at the same time; 4) OAT had negative, positive or no impacts on physiological functions of coral colonies; and 5) pooled data were not representative of responses of all individual colonies. Indeed, the pooled data obscured actual responses of individual colonies or presented a response that was not observed in any individual. From the results of this study we recommend improving experimental designs of studies investigating physiological responses of corals to climate change by complementing them with colony-specific examinations.

  5. The relationship between physical and biological habitat conditions and hermatypic coral recruits abundance within insular reefs (Colombian Caribbean).

    PubMed

    Bernal-Sotelo, Katherine; Acosta, Alberto

    2012-09-01

    Little evidence exists on the dependence between the presence and abundance of juvenile hermatypic corals and the conditions of their habitats, despite that juveniles contribute with the understanding of the community structure and its reproductive success. To assess this, the abundance of nine species of juvenile corals was correlated with eight macro-habitat (location of the reef on shelf, depth) and micro-habitat (type and inclination of the substrate, exposure to light, texture and amount of sediment accumulated on bottom, potential growth area for juveniles) conditions. Sampling was conducted in four insular coral reefs in the Colombian Caribbean: two oceanic and two continental reefs (influenced by large rivers), covering a total of 600m2 and the distribution of corals on a vertical gradient. Contingency tables and coefficients (magnitude) and multiple correspondence analyses were used to evaluate the dependency ratios for each species. The results showed that Agaricia tenuifolia displayed the most robust pattern of dependence (two high and two moderate), significant for juveniles present at a high frequency in continental reefs, devoid of potential area for juvenile growth (surrounded by macroalgae), and covering horizontal substrates exposed to light. The juveniles were associated with a habitat of moderate to high bottom accumulation of extremely fine sediment. Porites astreoides presented four moderate dependencies; ocean reefs between 2-16m depths, a high frequency of juveniles on horizontal substrates, exposed to light, non-sedimented and occupied by competitors. Siderastrea siderea displayed three moderate dependences for juveniles in cryptic zones, inclined substrate and devoid of competitors. A. lamarcki, Leptoseris cucullata and A. agaricites presented two moderate dependences; these species share high abundance of juveniles in habitats with no sediment, exposed to light and occupied by competitors (except A. agaricites). The P. porites, Favia

  6. Variability of Symbiodinium Communities in Waters, Sediments, and Corals of Thermally Distinct Reef Pools in American Samoa

    PubMed Central

    Cunning, Ross; Yost, Denise M.; Guarinello, Marisa L.; Putnam, Hollie M.; Gates, Ruth D.

    2015-01-01

    Reef-building corals host assemblages of symbiotic algae (Symbiodinium spp.) whose diversity and abundance may fluctuate under different conditions, potentially facilitating acclimatization to environmental change. The composition of free-living Symbiodinium in reef waters and sediments may also be environmentally labile and may influence symbiotic assemblages by mediating supply and dispersal. The magnitude and spatial scales of environmental influence over Symbiodinium composition in different reef habitat compartments are, however, not well understood. We used pyrosequencing to compare Symbiodinium in sediments, water, and ten coral species between two backreef pools in American Samoa with contrasting thermal environments. We found distinct compartmental assemblages of clades A, C, D, F, and/or G Symbiodinium types, with strong differences between pools in water, sediments, and two coral species. In the pool with higher and more variable temperatures, abundance of various clade A and C types differed compared to the other pool, while abundance of D types was lower in sediments but higher in water and in Pavona venosa, revealing an altered habitat distribution and potential linkages among compartments. The lack of between-pool effects in other coral species was due to either low overall variability (in the case of Porites) or high within-pool variability. Symbiodinium communities in water and sediment also showed within-pool structure, indicating that environmental influences may operate over multiple, small spatial scales. This work suggests that Symbiodinium composition is highly labile in reef waters, sediments, and some corals, but the underlying drivers and functional consequences of this plasticity require further testing with high spatial resolution biological and environmental sampling. PMID:26713847

  7. Polyphyly and hidden species among Hawai'i's dominant mesophotic coral genera, Leptoseris and Pavona (Scleractinia: Agariciidae).

    PubMed

    Luck, Daniel G; Forsman, Zac H; Toonen, Robert J; Leicht, Sarah J; Kahng, Samuel E

    2013-01-01

    Widespread polyphyly in stony corals (order Scleractinia) has prompted efforts to revise their systematics through approaches that integrate molecular and micromorphological evidence. To date, these approaches have not been comprehensively applied to the dominant genera in mesophotic coral ecosystems (MCEs) because several species in these genera occur primarily at depths that are poorly explored and from which sample collections are limited. This study is the first integrated morphological and molecular systematic analysis of the genera Leptoseris and Pavona to examine material both from shallow-water reefs (<30 m) and from mid- to lower-MCEs (>60 m). Skeletal and tissue samples were collected throughout the Hawaiian Archipelago between 2-127 m. A novel mitochondrial marker (cox1-1-rRNA intron) was sequenced for 70 colonies, and the micromorphologies of 94 skeletons, plus selected type material, were analyzed. The cox1-1-rRNA intron resolved 8 clades, yet Leptoseris and Pavona were polyphyletic. Skeletal micromorphology, especially costal ornamentation, showed strong correspondence and discrete differences between mitochondrial groups. One putative new Leptoseris species was identified and the global depth range of the genus Pavona was extended to 89 m, suggesting that the diversity of mesophotic scleractinians has been underestimated. Examination of species' depth distributions revealed a pattern of depth zonation: Species common in shallow-water were absent or rare >40 m, whereas others occurred only >60 m. These patterns emphasize the importance of integrated systematic analyses and more comprehensive sampling by depth in assessing the connectivity and diversity of MCEs.

  8. Coral bleaching: Thermal adaptation in reef coral symbionts

    NASA Astrophysics Data System (ADS)

    Rowan, Rob

    2004-08-01

    Many corals bleach as a result of increased seawater temperature, which causes them to lose their vital symbiotic algae (Symbiodinium spp.) - unless these symbioses are able to adapt to global warming, bleaching threatens coral reefs worldwide. Here I show that some corals have adapted to higher temperatures, at least in part, by hosting specifically adapted Symbiodinium. If other coral species can host these or similar Symbiodinium taxa, they might adapt to warmer habitats relatively easily.

  9. Patterns of species range evolution in Indo-Pacific reef assemblages reveal the Coral Triangle as a net source of transoceanic diversity

    PubMed Central

    Evans, Sean M.; McKenna, Caroline; Simpson, Stephen D.; Tournois, Jennifer

    2016-01-01

    The Coral Triangle in the Indo-Pacific is a region renowned for exceptional marine biodiversity. The area could have acted as a ‘centre of origin’ where speciation has been prolific or a ‘centre of survival’ by providing refuge during major environmental shifts such as sea-level changes. The region could also have acted as a ‘centre of accumulation’ for species with origins outside of the Coral Triangle, owing to it being at a central position between the Indian and Pacific oceans. Here, we investigated support for these hypotheses using population-level DNA sequence-based reconstructions of the range evolution of 45 species (314 populations) of Indo-Pacific reef-associated organisms. Our results show that populations undergoing the most ancient establishment were significantly more likely to be closer to the centre of the Coral Triangle than to peripheral locations. The data are consistent with the Coral Triangle being a net source of coral-reef biodiversity for the Indo-Pacific region, suggesting that the region has acted primarily as a centre of survival, a centre of origin or both. These results provide evidence of how a key location can influence the large-scale distributions of biodiversity over evolutionary timescales. PMID:27330168

  10. Unexpected cryptic species diversity in the widespread coral Seriatopora hystrix masks spatial-genetic patterns of connectivity.

    PubMed

    Warner, Patricia A; van Oppen, Madeleine J H; Willis, Bette L

    2015-06-01

    Mounting evidence of cryptic species in a wide range of taxa highlights the need for careful analyses of population genetic data sets to unravel within-species diversity from potential interspecies relationships. Here, we use microsatellite loci and hierarchical clustering analysis to investigate cryptic diversity in sympatric and allopatric (separated by 450 km) populations of the widespread coral Seriatopora hystrix on the Great Barrier Reef. Structure analyses delimited unique genetic clusters that were confirmed by phylogenetic and extensive population-level analyses. Each of four sympatric yet distinct genetic clusters detected within S. hystrix demonstrated greater genetic cohesion across regional scales than between genetic clusters within regions (<10 km). Moreover, the magnitude of genetic differentiation between different clusters (>0.620 G"ST ) was similar to the difference between S. hystrix clusters and the congener S. caliendrum (mean G"ST 0.720). Multiple lines of evidence, including differences in habitat specificity, mitochondrial identity, Symbiodinium associations and morphology, corroborate the nuclear genetic evidence that these distinct clusters constitute different species. Hierarchical clustering analysis combined with more traditional population genetic methods provides a powerful approach for delimiting species and should be regularly applied to ensure that ecological and evolutionary patterns interpreted for single species are not confounded by the presence of cryptic species.

  11. Assessing the ecological effects of human impacts on coral reefs in Bocas del Toro, Panama.

    PubMed

    Seemann, Janina; González, Cindy T; Carballo-Bolaños, Rodrigo; Berry, Kathryn; Heiss, Georg A; Struck, Ulrich; Leinfelder, Reinhold R

    2014-03-01

    Environmental and biological reef monitoring was conducted in Almirante Bay (Bahía Almirante) in Bocas del Toro, Panama, to assess impacts from anthropogenic developments. An integrated monitoring investigated how seasonal temperature stress, turbidity, eutrophication and physical impacts threatened reef health and biodiversity throughout the region. Environmental parameters such as total suspended solids [TSS], carbon isotopes (δ(13)C), C/N ratios, chlorophyll a, irradiance, secchi depth, size fractions of the sediments and isotope composition of dissolved inorganic carbon [DIC] of the water were measured throughout the years 2010 and 2011 and were analysed in order to identify different impact sources. Compared to data from Collin et al. (Smithsonian Contributions to the Marine Sciences 38:324-334, 2009) chlorophyll a has doubled at sites close to the city and the port Almirante (from 0.46-0.49 to 0.78-0.97 μg l(-1)) and suspension load increased, visible by a decrease in secchi depth values. Visibility decreased from 9-13 m down to 4 m at the bay inlet Boca del Drago, which is strongly exposed to river run off and dredging for the shipping traffic. Eutrophication and turbidity levels seemed to be the determining factor for the loss of hard coral diversity, most significant at chlorophyll a levels higher than 0.5 μg l(-1) and TSS levels higher than 4.7 mg l(-1). Hard coral cover within the bay has also declined, at some sites down to <10 % with extremely low diversities (7 hard coral species). The hard coral species Porites furcata dominated the reefs in highly impacted areas and showed a strong recovery after bleaching and a higher tolerance to turbidity and eutrophication compared to other hard coral species in the bay. Serious overfishing was detected in the region by a lack of adult and carnivorous fish species, such as grunts, snappers and groupers. Study sites less impacted by anthropogenic activities and/or those with local protection showed a

  12. Patterns of bacteria-host associations suggest different ecological strategies between two reef building cold-water coral species

    NASA Astrophysics Data System (ADS)

    Meistertzheim, Anne.-Leila; Lartaud, Franck; Arnaud-Haond, Sophie; Kalenitchenko, Dimitri; Bessalam, Manon; Le Bris, Nadine; Galand, Pierre E.

    2016-08-01

    Cold-water corals (CWC) are main ecosystem engineers of the deep sea, and their reefs constitute hot-spots of biodiversity. However, their ecology remains poorly understood, particularly, the nature of the holobiont formed by corals with their associated bacterial communities. Here, we analyzed Madrepora oculata and Lophelia pertusa samples, collected from one location in a Mediterranean canyon in two different seasons (autumn and spring), in order to test for species specificity and temporal stability of the host-bacteria associations. The 16S rRNA sequencing revealed host-specific patterns of bacterial communities associated with L. pertusa and M. oculata, both in terms of community composition and diversity. All analyzed M. oculata polyps exhibited temporally and spatially similar bacterial communities dominated by haplotypes homologous to the known cnidarians-associated genus Endozoicomonas. In contrast, the bacterial communities associated with L. pertusa varied among polyps from the same colony, as well as among distinct colonies and between seasons. While the resilient consortium formed by M. oculata and its bacterial community fit the definition of holobiont, the versatility of the L. pertusa microbiome suggests that this association is more influenced by the environmental conditions or nutritional status. Our results thus highlight distinct host/microbes association strategies for these two closely related Scleractinians sharing the same habitat, suggesting distinct sensitivity to environmental change.

  13. Growth of Western Australian corals in the anthropocene.

    PubMed

    Cooper, Timothy F; O'Leary, Rebecca A; Lough, Janice M

    2012-02-03

    Anthropogenic increases of atmospheric carbon dioxide lead to warmer sea surface temperatures and altered ocean chemistry. Experimental evidence suggests that coral calcification decreases as aragonite saturation drops but increases as temperatures rise toward thresholds optimal for coral growth. In situ studies have documented alarming recent declines in calcification rates on several tropical coral reef ecosystems. We show there is no widespread pattern of consistent decline in calcification rates of massive Porites during the 20th century on reefs spanning an 11° latitudinal range in the southeast Indian Ocean off Western Australia. Increasing calcification rates on the high-latitude reefs contrast with the downward trajectory reported for corals on Australia's Great Barrier Reef and provide additional evidence that recent changes in coral calcification are responses to temperature rather than ocean acidification.

  14. Heterotrophy in tropical scleractinian corals.

    PubMed

    Houlbrèque, Fanny; Ferrier-Pagès, Christine

    2009-02-01

    The dual character of corals, that they are both auto- and heterotrophs, was recognized early in the twentieth Century. It is generally accepted that the symbiotic association between corals and their endosymbiotic algae (called zooxanthellae) is fundamental to the development of coral reefs in oligotrophic tropical oceans because zooxanthellae transfer the major part of their photosynthates to the coral host (autotrophic nutrition). However, numerous studies have confirmed that many species of corals are also active heterotrophs, ingesting organisms ranging from bacteria to mesozooplankton. Heterotrophy accounts for between 0 and 66% of the fixed carbon incorporated into coral skeletons and can meet from 15 to 35% of daily metabolic requirements in healthy corals and up to 100% in bleached corals. Apart from this carbon input, feeding is likely to be important to most scleractinian corals, since nitrogen, phosphorus, and other nutrients that cannot be supplied from photosynthesis by the coral's symbiotic algae must come from zooplankton capture, particulate matter or dissolved compounds. A recent study showed that during bleaching events some coral species, by increasing their feeding rates, are able to maintain and restore energy reserves. This review assesses the importance and effects of heterotrophy in tropical scleractinian corals. We first provide background information on the different food sources (from dissolved organic matter to meso- and macrozooplankton). We then consider the nutritional inputs of feeding. Finally, we review feeding effects on the different physiological parameters of corals (tissue composition, photosynthesis and skeletal growth).

  15. Polyphyly and hidden species among Hawaiʻi’s dominant mesophotic coral genera, Leptoseris and Pavona (Scleractinia: Agariciidae)

    PubMed Central

    Forsman, Zac H.; Toonen, Robert J.; Leicht, Sarah J.; Kahng, Samuel E.

    2013-01-01

    Widespread polyphyly in stony corals (order Scleractinia) has prompted efforts to revise their systematics through approaches that integrate molecular and micromorphological evidence. To date, these approaches have not been comprehensively applied to the dominant genera in mesophotic coral ecosystems (MCEs) because several species in these genera occur primarily at depths that are poorly explored and from which sample collections are limited. This study is the first integrated morphological and molecular systematic analysis of the genera Leptoseris and Pavona to examine material both from shallow-water reefs (<30 m) and from mid- to lower-MCEs (>60 m). Skeletal and tissue samples were collected throughout the Hawaiian Archipelago between 2–127 m. A novel mitochondrial marker (cox1-1-rRNA intron) was sequenced for 70 colonies, and the micromorphologies of 94 skeletons, plus selected type material, were analyzed. The cox1-1-rRNA intron resolved 8 clades, yet Leptoseris and Pavona were polyphyletic. Skeletal micromorphology, especially costal ornamentation, showed strong correspondence and discrete differences between mitochondrial groups. One putative new Leptoseris species was identified and the global depth range of the genus Pavona was extended to 89 m, suggesting that the diversity of mesophotic scleractinians has been underestimated. Examination of species’ depth distributions revealed a pattern of depth zonation: Species common in shallow-water were absent or rare >40 m, whereas others occurred only >60 m. These patterns emphasize the importance of integrated systematic analyses and more comprehensive sampling by depth in assessing the connectivity and diversity of MCEs. PMID:24032091

  16. Patterns of coral disease across the Hawaiian Archipelago: Relating disease to environment

    USGS Publications Warehouse

    Aeby, G.S.; Williams, G.J.; Franklin, E.C.; Kenyon, J.; Cox, E.F.; Coles, S.; Work, T.M.

    2011-01-01

    In Hawaii, coral reefs occur across a gradient of biological (host abundance), climatic (sea surface temperature anomalies) and anthropogenic conditions from the human-impacted reefs of the main Hawaiian Islands (MHI) to the pristine reefs of the northwestern Hawaiian Islands (NWHI). Coral disease surveys were conducted at 142 sites from across the Archipelago and disease patterns examined. Twelve diseases were recorded from three coral genera (Porites, Montipora, Acropora) with Porites having the highest prevalence. Porites growth anomalies (PorGAs) were significantly more prevalent within and indicative of reefs in the MHI and Porites trematodiasis (PorTrm) was significantly more prevalent within and indicative of reefs in the NWHI. Porites tissue loss syndrome (PorTLS) was also important in driving regional differences but that relationship was less clear. These results highlight the importance of understanding disease ecology when interpreting patterns of disease occurrence. PorTrm is caused by a parasitic flatworm that utilizes multiple hosts during its life cycle (fish, mollusk and coral). All three hosts must be present for the disease to occur and higher host abundance leads to higher disease prevalence. Thus, a high prevalence of PorTrm on Hawaiian reefs would be an indicator of a healthy coral reef ecosystem. In contrast, the high occurrence of PorGAs within the MHI suggests that PorGAs are related, directly or indirectly, to some environmental co-factor associated with increased human population sizes. Focusing on the three indicator diseases (PorGAs, PorTrm, PorTLS) we used statistical modeling to examine the underlying associations between disease prevalence and 14 different predictor variables (biotic and abiotic). All three diseases showed positive associations with host abundance and negative associations with thermal stress. The association with human population density differed among disease states with PorGAs showing a positive and PorTrm showing

  17. The distribution of the thermally tolerant symbiont lineage (Symbiodinium clade D) in corals from Hawaii: correlations with host and the history of ocean thermal stress.

    PubMed

    Stat, Michael; Pochon, Xavier; Franklin, Erik C; Bruno, John F; Casey, Kenneth S; Selig, Elizabeth R; Gates, Ruth D

    2013-05-01

    Spatially intimate symbioses, such as those between scleractinian corals and unicellular algae belonging to the genus Symbiodinium, can potentially adapt to changes in the environment by altering the taxonomic composition of their endosymbiont communities. We quantified the spatial relationship between the cumulative frequency of thermal stress anomalies (TSAs) and the taxonomic composition of Symbiodinium in the corals Montipora capitata, Porites lobata, and Porites compressa across the Hawaiian archipelago. Specifically, we investigated whether thermally tolerant clade D Symbiodinium was in greater abundance in corals from sites with high frequencies of TSAs. We recovered 2305 Symbiodinium ITS2 sequences from 242 coral colonies in lagoonal reef habitats at Pearl and Hermes Atoll, French Frigate Shoals, and Kaneohe Bay, Oahu in 2007. Sequences were grouped into 26 operational taxonomic units (OTUs) with 12 OTUs associated with Montipora and 21 with Porites. Both coral genera associated with Symbiodinium in clade C, and these co-occurred with clade D in M. capitata and clade G in P. lobata. The latter represents the first report of clade G Symbiodinium in P. lobata. In M. capitata (but not Porites spp.), there was a significant correlation between the presence of Symbiodinium in clade D and a thermal history characterized by high cumulative frequency of TSAs. The endogenous community composition of Symbiodinium and an association with clade D symbionts after long-term thermal disturbance appear strongly dependent on the taxa of the coral host.

  18. The distribution of the thermally tolerant symbiont lineage (Symbiodinium clade D) in corals from Hawaii: correlations with host and the history of ocean thermal stress

    PubMed Central

    Stat, Michael; Pochon, Xavier; Franklin, Erik C; Bruno, John F; Casey, Kenneth S; Selig, Elizabeth R; Gates, Ruth D

    2013-01-01

    Spatially intimate symbioses, such as those between scleractinian corals and unicellular algae belonging to the genus Symbiodinium, can potentially adapt to changes in the environment by altering the taxonomic composition of their endosymbiont communities. We quantified the spatial relationship between the cumulative frequency of thermal stress anomalies (TSAs) and the taxonomic composition of Symbiodinium in the corals Montipora capitata, Porites lobata, and Porites compressa across the Hawaiian archipelago. Specifically, we investigated whether thermally tolerant clade D Symbiodinium was in greater abundance in corals from sites with high frequencies of TSAs. We recovered 2305 Symbiodinium ITS2 sequences from 242 coral colonies in lagoonal reef habitats at Pearl and Hermes Atoll, French Frigate Shoals, and Kaneohe Bay, Oahu in 2007. Sequences were grouped into 26 operational taxonomic units (OTUs) with 12 OTUs associated with Montipora and 21 with Porites. Both coral genera associated with Symbiodinium in clade C, and these co-occurred with clade D in M. capitata and clade G in P. lobata. The latter represents the first report of clade G Symbiodinium in P. lobata. In M. capitata (but not Porites spp.), there was a significant correlation between the presence of Symbiodinium in clade D and a thermal history characterized by high cumulative frequency of TSAs. The endogenous community composition of Symbiodinium and an association with clade D symbionts after long-term thermal disturbance appear strongly dependent on the taxa of the coral host. PMID:23762518

  19. Analysis of complete mitochondrial DNA sequences of three members of the Montastraea annularis coral species complex (Cnidaria, Anthozoa, Scleractinia)

    NASA Astrophysics Data System (ADS)

    Fukami, Hironobu; Knowlton, Nancy

    2005-11-01

    Complete mitochondrial nucleotide sequences of two individuals each of Montastraea annularis, Montastraea faveolata, and Montastraea franksi were determined. Gene composition and order differed substantially from the sea anemone Metridium senile, but were identical to that of the phylogenetically distant coral genus Acropora. However, characteristics of the non-coding regions differed between the two scleractinian genera. Among members of the M. annularis complex, only 25 of 16,134 base pair positions were variable. Sixteen of these occurred in one colony of M. franksi, which (together with additional data) indicates the existence of multiple divergent mitochondrial lineages in this species. Overall, rates of evolution for these mitochondrial genomes were extremely slow (0.03 0.04% per million years based on the fossil record of the M. annularis complex). At higher taxonomic levels, patterns of genetic divergence and synonymous/nonsynonymous substitutions suggest non-neutral and unequal rates of evolution between the two lineages to which Montastraea and Acropora belong.

  20. Harryplax severus, a new genus and species of an unusual coral rubble-inhabiting crab from Guam (Crustacea, Brachyura, Christmaplacidae)

    PubMed Central

    Mendoza, Jose C. E.; Ng, Peter K. L.

    2017-01-01

    Abstract Harryplax severus, a new genus and species of coral rubble-dwelling pseudozioid crab is described from the island of Guam in the western Pacific Ocean. The unusual morphological features of its carapace, thoracic sternum, eyes, antennules, pereopods and gonopods place it in the family Christmaplacidae Naruse & Ng, 2014. A suite of characters on the cephalothorax, pleon and appendages distinguishes Harryplax severus gen. & sp. n. from the previously sole representative of the family, Christmaplax mirabilis Naruse & Ng, 2014, described from Christmas Island in the eastern Indian Ocean. This represents the first record of Christmaplacidae in the Pacific Ocean. With the discovery of a second genus, a revised diagnosis for Christmaplacidae is provided. PMID:28325962

  1. Stability of a coral reef fish community following a catastrophic storm

    NASA Astrophysics Data System (ADS)

    Walsh, William J.

    1983-08-01

    In January 1980, a severe 3 day storm struck the normally protected leeward coral reefs of Kona, Hawaii. Waves generated by the storm, which was estimated to be a once in 20 40 year occurrence, were in excess of 6 m and caused extensive reef destruction and shoreline alteration. Shallow nearshore areas were denuded of most bottom cover and marine life. Damage to corals was extensive with broken colonies of the coral Porites compressa occurring down to depths of 27 m. Pronounced algal blooms occurred in a clearly defined sequence subsequent to the storm. The patterns of both coral destruction and algal succession were similar to those described on other storm damaged reefs. Fish mortality directly attributable to the storm was slight and the few dead fishes noted were either surge zone or tide pool species. After the storm the shallow reef flat was devoid of resident fishes while deeper areas contained many fishes which had moved from shallower water. This habitat shift substantially reduced the immediate impact of the storm on the fish community. Despite considerable habitat destruction that resulted from the storm, there were no decreases in species or population abundances on five 25 m2 quadrats monitored for 23 months before and 16 months after the storm. Similarly, the numbers of triggerfish sheltering within an area increased even though the storm reduced the number of available shelter holes. The shelter and space-related carrying capacity of these areas prior to the storm may therefore not have been reached. Recolonization of evacuated areas by fishes began shortly after the storm and within 16 months many areas had regained their prestorm appearances. Large numbers of individuals remained however, in their shifted locations.

  2. Behavioural and developmental responses of predatory coral reef fish to variation in the abundance of prey

    NASA Astrophysics Data System (ADS)

    Beukers-Stewart, B. D.; Beukers-Stewart, J. S.; Jones, G. P.

    2011-09-01

    Ecological theory suggests that the behaviour, growth and abundance of predators will be strongly influenced by the abundance of prey. Predators may in turn play an important role in structuring prey populations and communities. Responses of predators to variation in prey abundance have most commonly been demonstrated in low-diversity communities where food webs are relatively simple. How predators respond in highly diverse assemblages such as in coral reef habitats is largely unknown. This study describes an experiment that examined how the movement, diet and growth of the coral reef piscivore, Cephalopholis boenak (Serranidae) responded to variation in the abundance of its prey. Predator densities were standardised on small patch reefs made from the lagoonal reef-building coral, Porites cylindrica. These patch reefs exhibited natural variation in the abundance and community structure of multiple species of prey. However, our experiment generated a relatively simple predator-prey relationship, with C. boenak primarily responding to the most abundant species of prey. Three responses of predators were observed: aggregative, functional and developmental. Thirty-one per cent of individuals moved between patch reefs during the experiment, all from areas of relatively low to high prey density. Feeding rates were higher on patch reefs of high prey density, while growth rates of fish that remained on low prey density reefs throughout the experiment were lower. Growth rates of C. boenak on the experimental reefs were also much higher than for those living on natural patch reefs over the same time period, corresponding with overall differences in prey abundance. These results suggest that local abundance, feeding rate and growth of C. boenak were closely linked to the abundance of their main prey. This combination of predatory responses is a potential mechanism behind recent observations of density-dependent mortality and population regulation of prey in coral reef fish

  3. Spatial distribution of fifty ornamental fish species on coral reefs in the Red Sea and Gulf of Aden

    PubMed Central

    Khalaf, Maroof A.; Abdallah, Mohamed

    2014-01-01

    Abstract The spatial distribution of 50 ornamental fish species from shallow water habitats on coral reefs were investigated using visual census techniques, between latitudes 11−29°N in the Red Sea, in Jordan, Egypt, Saudi Arabia, and Yemen, and in the adjacent Gulf of Aden in Djibouti. One hundred eighteen transects (each 100×5 m) were examined in 29 sites (3−8 sites per country). A total of 522,523 fish individuals were counted during this survey, with mean abundance of 4428.2 ± 87.26 individual per 500 m² transect. In terms of relative abundance (RA), the most abundant species were Blue green damselfish, Chromis viridis (RA=54.4%),followed bySea goldie, Pseudanthias squamipinnis (RA= 34.7), Whitetail dascyllus, Dascyllus aruanus (RA= 2.6%), Marginate dascyllus, Dascyllus marginatus (RA= 2.0),Red Sea eightline flasher Paracheilinus octotaenia (RA=1.0),andKlunzinger’s wrasse, Thalassoma rueppellii (0.7%). The highest number of species (S) per 500 m² transect was found on reefs at the latitude 20° in Saudi Arabia (S=21.8), and the lowest number of species was found at the latitude 15° in Djibouti (S=11.11). The highest mean abundance (8565.8) was found on reefs at latitude 20° in Saudi Arabia and the lowest mean abundance (230) was found on reefs at latitude 22°, also in Saudi Arabia. Whereas, the highest Shannon-Wiener Diversity Index was found in reefs at the latitude 22° (H`=2.4) and the lowest was found in reefs at the latitude 20° (H`=0.6). This study revealed marked differences in the structure of ornamental fish assemblages with latitudinal distribution. The data support the presence of two major biogeographic groups of fishes in the Red Sea and Gulf of Aden: the southern Red Sea and Gulf of Aden group and the group in the northern and central Red Sea. Strong correlations were found between live coral cover and the number of fish species, abundance and Shannon-Wiener Diversity indices, and the strength of these correlations varied among the

  4. Spatial distribution of fifty ornamental fish species on coral reefs in the Red Sea and Gulf of Aden.

    PubMed

    Khalaf, Maroof A; Abdallah, Mohamed

    2014-01-01

    The spatial distribution of 50 ornamental fish species from shallow water habitats on coral reefs were investigated using visual census techniques, between latitudes 11-29°N in the Red Sea, in Jordan, Egypt, Saudi Arabia, and Yemen, and in the adjacent Gulf of Aden in Djibouti. One hundred eighteen transects (each 100×5 m) were examined in 29 sites (3-8 sites per country). A total of 522,523 fish individuals were counted during this survey, with mean abundance of 4428.2 ± 87.26 individual per 500 m² transect. In terms of relative abundance (RA), the most abundant species were Blue green damselfish, Chromis viridis (RA=54.4%),followed bySea goldie, Pseudanthias squamipinnis (RA= 34.7), Whitetail dascyllus, Dascyllus aruanus (RA= 2.6%), Marginate dascyllus, Dascyllus marginatus (RA= 2.0),Red Sea eightline flasher Paracheilinus octotaenia (RA=1.0),andKlunzinger's wrasse, Thalassoma rueppellii (0.7%). The highest number of species (S) per 500 m² transect was found on reefs at the latitude 20° in Saudi Arabia (S=21.8), and the lowest number of species was found at the latitude 15° in Djibouti (S=11.11). The highest mean abundance (8565.8) was found on reefs at latitude 20° in Saudi Arabia and the lowest mean abundance (230) was found on reefs at latitude 22°, also in Saudi Arabia. Whereas, the highest Shannon-Wiener Diversity Index was found in reefs at the latitude 22° (H`=2.4) and the lowest was found in reefs at the latitude 20° (H`=0.6). This study revealed marked differences in the structure of ornamental fish assemblages with latitudinal distribution. The data support the presence of two major biogeographic groups of fishes in the Red Sea and Gulf of Aden: the southern Red Sea and Gulf of Aden group and the group in the northern and central Red Sea. Strong correlations were found between live coral cover and the number of fish species, abundance and Shannon-Wiener Diversity indices, and the strength of these correlations varied among the reefs. A

  5. Coral Sr/Ca-based sea surface temperature and air temperature variability from the inshore and offshore corals in the Seribu Islands, Indonesia.

    PubMed

    Cahyarini, Sri Yudawati; Zinke, Jens; Troelstra, Simon; Suharsono; Aldrian, Edvin; Hoeksema, B W

    2016-09-30

    The ability of massive Porites corals to faithfully record temperature is assessed. Porites corals from Kepulauan Seribu were sampled from one inshore and one offshore site and analyzed for their Sr/Ca variation. The results show that Sr/Ca of the offshore coral tracked SST, while Sr/Ca variation of the inshore coral tracked ambient air temperature. In particular, the inshore SST variation is related to air temperature anomalies of the urban center of Jakarta. The latter we relate to air-sea interactions modifying inshore SST associated with the land-sea breeze mechanism and/or monsoonal circulation. The correlation pattern of monthly coral Sr/Ca with the Niño3.4 index and SEIO-SST reveals that corals in the Seribu islands region respond differently to remote forcing. An opposite response is observed for inshore and offshore corals in response to El Niño onset, yet similar to El Niño mature phase (December to February). SEIO SSTs co-vary strongly with SST and air temperature variability across the Seribu island reef complex. The results of this study clearly indicate that locations of coral proxy record in Indonesia need to be chosen carefully in order to identify the seasonal climate response to local and remote climate and anthropogenic forcing.

  6. Vertical water mass structure in the North Atlantic influences the bathymetric distribution of species in the deep-sea coral genus Paramuricea

    NASA Astrophysics Data System (ADS)

    Radice, Veronica Z.; Quattrini, Andrea M.; Wareham, Vonda E.; Edinger, Evan N.; Cordes, Erik E.

    2016-10-01

    Deep-sea corals are the structural foundation of their ecosystems along continental margins worldwide, yet the factors driving their broad distribution are poorly