Diseases of corals with particular reference to Indian reefs

Digital Repository Service at National Institute of Oceanography (India)

Ravindran, J.; Raghukumar, C.

Diseases are one of the factors that change the structure and functioning of coral-reef communities as they cause irreversible damage to the corals Reports on coral diseases describe the etiological agents responsible for the disease and in a few...

Distribution and abundance of elkhorn coral, Acropora palmata, and prevalence of white-band disease at Buck Island Reef National Monument, St. Croix, US Virgin Islands

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Mayor, Philippe A.; Rogers, Caroline S.; Hillis-Starr, Zandy M.

2006-05-01

In the 1970s and 1980s elkhorn coral, Acropora palmata, declined dramatically throughout the Caribbean primarily due to white-band disease (WBD). In 2005, elkhorn coral was proposed for listing as threatened under the US Endangered Species Act. WBD was first documented at Buck Island Reef National Monument (BIRNM). Together with hurricanes WBD reduced live elkhorn coral coverage by probably over 90%. In the past decade some recovery has been observed at BIRNM. This study assessed the distribution and abundance of elkhorn coral and estimated the prevalence of WBD at the monument. Within an area of 795 ha, we estimated 97,232 134,371 (95% confidence limits) elkhorn coral colonies with any dimension of connected live tissue greater than one meter, about 3% of which were infected by WBD. Despite some recovery, the elkhorn coral density remains low and WBD may continue to present a threat to the elkhorn coral population.

Metatranscriptome analysis of the reef-building coral Orbicella faveolata indicates holobiont response to coral disease

KAUST Repository

Daniels, Camille Arian

2015-09-11

White Plague Disease (WPD) is implicated in coral reef decline in the Caribbean and is characterized by microbial community shifts in coral mucus and tissue. Studies thus far have focused on assessing microbial communities or the identification of specific pathogens, yet few have addressed holobiont response across metaorganism compartments in coral disease. Here, we report on the first metatranscriptomic assessment of the coral host, algal symbiont, and microbial compartment in order to survey holobiont structure and function in healthy and diseased samples from Orbicella faveolata collected at reef sites off Puerto Rico. Our data indicate holobiont-wide as well as compartment-specific responses to WPD. Gene expression changes in the diseased coral host involved proteins playing a role in innate immunity, cytoskeletal integrity, cell adhesion, oxidative stress, chemical defense, and retroelements. In contrast, the algal symbiont showed comparatively few expression changes, but of large magnitude, of genes related to stress, photosynthesis, and metal transport. Concordant with the coral host response, the bacterial compartment showed increased abundance of heat shock proteins, genes related to oxidative stress, DNA repair, and potential retroelement activity. Importantly, analysis of the expressed bacterial gene functions establishes the participation of multiple bacterial families in WPD pathogenesis and also suggests a possible involvement of viruses and/or phages in structuring the bacterial assemblage. In this study, we implement an experimental approach to partition the coral holobiont and resolve compartment- and taxa-specific responses in order to understand metaorganism function in coral disease.

Metatranscriptome analysis of the reef-buidling coral Orbicella faveolata indicates holobiont response to coral disease

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Camille eDaniels

2015-09-01

Full Text Available White Plague Disease (WPD is implicated in coral reef decline in the Caribbean and is characterized by microbial community shifts in coral mucus and tissue. Studies thus far have focused on assessing microbial communities or the identification of specific pathogens, yet few have addressed holobiont response across metaorganism compartments in coral disease. Here, we report on the first metatranscriptomic assessment of the coral host, algal symbiont, and microbial compartment in order to survey holobiont structure and function in healthy and diseased samples from Orbicella faveolata collected at reef sites off Puerto Rico. Our data indicate metaorganism-wide as well as compartment-specific responses to WPD. Gene expression changes in the diseased coral host involved proteins playing a role in innate immunity, cytoskeletal integrity, cell adhesion, oxidative stress, chemical defense, and retroelements. In contrast, the algal symbiont showed comparatively few expression changes, but of large magnitude, of genes related to stress, photosynthesis, and metal transport. Concordant with the coral host response, the bacterial compartment showed increased abundance of heat shock proteins, genes related to oxidative stress, DNA repair, and potential retroelement activity. Importantly, analysis of the expressed bacterial gene functions establishes the participation of multiple bacterial families in WPD pathogenesis and also suggests a possible involvement of viruses and/or phages in structuring the bacterial assemblage. In this study, we implement an experimental approach to partition the coral holobiont and resolve compartment- and taxa-specific responses in order to understand metaorganism function in coral disease.

Metatranscriptome analysis of the reef-building coral Orbicella faveolata indicates holobiont response to coral disease

KAUST Repository

Daniels, Camille Arian; Baumgarten, Sebastian; Yum, Lauren; Michell, Craig; Bayer, Till; Arif, Chatchanit; Roder, Cornelia; Weil, Ernesto; Voolstra, Christian R.

2015-01-01

White Plague Disease (WPD) is implicated in coral reef decline in the Caribbean and is characterized by microbial community shifts in coral mucus and tissue. Studies thus far have focused on assessing microbial communities or the identification of specific pathogens, yet few have addressed holobiont response across metaorganism compartments in coral disease. Here, we report on the first metatranscriptomic assessment of the coral host, algal symbiont, and microbial compartment in order to survey holobiont structure and function in healthy and diseased samples from Orbicella faveolata collected at reef sites off Puerto Rico. Our data indicate holobiont-wide as well as compartment-specific responses to WPD. Gene expression changes in the diseased coral host involved proteins playing a role in innate immunity, cytoskeletal integrity, cell adhesion, oxidative stress, chemical defense, and retroelements. In contrast, the algal symbiont showed comparatively few expression changes, but of large magnitude, of genes related to stress, photosynthesis, and metal transport. Concordant with the coral host response, the bacterial compartment showed increased abundance of heat shock proteins, genes related to oxidative stress, DNA repair, and potential retroelement activity. Importantly, analysis of the expressed bacterial gene functions establishes the participation of multiple bacterial families in WPD pathogenesis and also suggests a possible involvement of viruses and/or phages in structuring the bacterial assemblage. In this study, we implement an experimental approach to partition the coral holobiont and resolve compartment- and taxa-specific responses in order to understand metaorganism function in coral disease.

Plastic waste associated with disease on coral reefs.

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Lamb, Joleah B; Willis, Bette L; Fiorenza, Evan A; Couch, Courtney S; Howard, Robert; Rader, Douglas N; True, James D; Kelly, Lisa A; Ahmad, Awaludinnoer; Jompa, Jamaluddin; Harvell, C Drew

2018-01-26

Plastic waste can promote microbial colonization by pathogens implicated in outbreaks of disease in the ocean. We assessed the influence of plastic waste on disease risk in 124,000 reef-building corals from 159 reefs in the Asia-Pacific region. The likelihood of disease increases from 4% to 89% when corals are in contact with plastic. Structurally complex corals are eight times more likely to be affected by plastic, suggesting that microhabitats for reef-associated organisms and valuable fisheries will be disproportionately affected. Plastic levels on coral reefs correspond to estimates of terrestrial mismanaged plastic waste entering the ocean. We estimate that 11.1 billion plastic items are entangled on coral reefs across the Asia-Pacific and project this number to increase 40% by 2025. Plastic waste management is critical for reducing diseases that threaten ecosystem health and human livelihoods. Copyright © 2018, The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Disturbance driven colony fragmentation as a driver of a coral disease outbreak.

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Marilyn E Brandt

Full Text Available In September of 2010, Brewer's Bay reef, located in St. Thomas (U.S. Virgin Islands, was simultaneously affected by abnormally high temperatures and the passage of a hurricane that resulted in the mass bleaching and fragmentation of its coral community. An outbreak of a rapid tissue loss disease among coral colonies was associated with these two disturbances. Gross lesion signs and lesion progression rates indicated that the disease was most similar to the Caribbean coral disease white plague type 1. Experiments indicated that the disease was transmissible through direct contact between colonies, and five-meter radial transects showed a clustered spatial distribution of disease, with diseased colonies being concentrated within the first meter of other diseased colonies. Disease prevalence and the extent to which colonies were bleached were both significantly higher on unattached colony fragments than on attached colonies, and disease occurred primarily on fragments found in direct contact with sediment. In contrast to other recent studies, disease presence was not related to the extent of bleaching on colonies. The results of this study suggest that colony fragmentation and contact with sediment played primary roles in the initial appearance of disease, but that the disease was capable of spreading among colonies, which suggests secondary transmission is possible through some other, unidentified mechanism.

Bacterial profiling of White Plague Disease across corals and oceans indicates a conserved and distinct disease microbiome

KAUST Repository

Roder, C.

2014-01-29

Coral diseases are characterized by microbial community shifts in coral mucus and tissue, but causes and consequences of these changes are vaguely understood due to the complexity and dynamics of coral-associated bacteria. We used 16S rRNA gene microarrays to assay differences in bacterial assemblages of healthy and diseased colonies displaying White Plague Disease (WPD) signs from two closely related Caribbean coral species, Orbicella faveolata and Orbicella franksi. Analysis of differentially abundant operational taxonomic units (OTUs) revealed strong differences between healthy and diseased specimens, but not between coral species. A subsequent comparison to data from two Indo-Pacific coral species (Pavona duerdeni and Porites lutea) revealed distinct microbial community patterns associated with ocean basin, coral species and health state. Coral species were clearly separated by site, but also, the relatedness of the underlying bacterial community structures resembled the phylogenetic relationship of the coral hosts. In diseased samples, bacterial richness increased and putatively opportunistic bacteria were consistently more abundant highlighting the role of opportunistic conditions in structuring microbial community patterns during disease. Our comparative analysis shows that it is possible to derive conserved bacterial footprints of diseased coral holobionts that might help in identifying key bacterial species related to the underlying etiopathology. Furthermore, our data demonstrate that similar-appearing disease phenotypes produce microbial community patterns that are consistent over coral species and oceans, irrespective of the putative underlying pathogen. Consequently, profiling coral diseases by microbial community structure over multiple coral species might allow the development of a comparative disease framework that can inform on cause and relatedness of coral diseases. 2013 The Authors Molecular Ecology John Wiley & Sons Ltd.

THE CONDITION OF CORAL REEFS IN SOUTH FLORIDA (2000) USING CORAL DISEASE AND BLEACHING AS INDICATORS

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The destruction for coral reef habitats is occurring at unprecedented levels. Coral disease epizootics in the Southwestern Atlantic have lead to coral replacement by turf algae, prompting a call to classify some coral species as endangered. In addition, a massive bleaching event ...

Anthropogenic mortality on coral reefs in Caribbean Panama predates coral disease and bleaching.

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Cramer, Katie L; Jackson, Jeremy B C; Angioletti, Christopher V; Leonard-Pingel, Jill; Guilderson, Thomas P

2012-06-01

Caribbean reef corals have declined precipitously since the 1980s due to regional episodes of bleaching, disease and algal overgrowth, but the extent of earlier degradation due to localised historical disturbances such as land clearing and overfishing remains unresolved. We analysed coral and molluscan fossil assemblages from reefs near Bocas del Toro, Panama to construct a timeline of ecological change from the 19th century-present. We report large changes before 1960 in coastal lagoons coincident with extensive deforestation, and after 1960 on offshore reefs. Striking changes include the demise of previously dominant staghorn coral Acropora cervicornis and oyster Dendrostrea frons that lives attached to gorgonians and staghorn corals. Reductions in bivalve size and simplification of gastropod trophic structure further implicate increasing environmental stress on reefs. Our paleoecological data strongly support the hypothesis, from extensive qualitative data, that Caribbean reef degradation predates coral bleaching and disease outbreaks linked to anthropogenic climate change. © 2012 Blackwell Publishing Ltd/CNRS.

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

KAUST Repository

Roder, Cornelia

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.

Words matter: Recommendations for clarifying coral disease nomenclature and terminology

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Rogers, Caroline S.

2010-01-01

Coral diseases have caused significant losses on Caribbean reefs and are becoming a greater concern in the Pacific. Progress in coral disease research requires collaboration and communication among experts from many different disciplines. The lack of consistency in the use of terms and names in the recent scientific literature reflects the absence of an authority for naming coral diseases, a lack of consensus on the meaning of even some of the most basic terms as they apply to corals, and imprecision in the use of descriptive words. The lack of consensus partly reflects the complexity of this newly emerging field of research. Establishment of a nomenclature committee under the Coral Disease and Health Consortium (CDHC) could lead to more standardized definitions and could promote use of appropriate medical terminology for describing and communicating disease conditions in corals. This committee could also help to define disease terminology unique to corals where existing medical terminology is not applicable. These efforts will help scientists communicate with one another and with the general public more effectively. Scientists can immediately begin to reduce some of the confusion simply by explicitly defining the words they are using. In addition, digital photographs can be posted on the CDHC website and included in publications to document the macroscopic (gross) signs of the conditions observed on coral colonies along with precisely written characterizations and descriptions.

Global coral disease prevalence associated with sea temperature anomalies and local factors.

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Ruiz-Moreno, Diego; Willis, Bette L; Page, A Cathie; Weil, Ernesto; Cróquer, Aldo; Vargas-Angel, Bernardo; Jordan-Garza, Adán Guillermo; Jordán-Dahlgren, Eric; Raymundo, Laurie; Harvell, C Drew

2012-09-12

Coral diseases are taking an increasing toll on coral reef structure and biodiversity and are important indicators of declining health in the oceans. We implemented standardized coral disease surveys to pinpoint hotspots of coral disease, reveal vulnerable coral families and test hypotheses about climate drivers from 39 locations worldwide. We analyzed a 3 yr study of coral disease prevalence to identify links between disease and a range of covariates, including thermal anomalies (from satellite data), location and coral cover, using a Generalized Linear Mixed Model. Prevalence of unhealthy corals, i.e. those with signs of known diseases or with other signs of compromised health, exceeded 10% on many reefs and ranged to over 50% on some. Disease prevalence exceeded 10% on 20% of Caribbean reefs and 2.7% of Pacific reefs surveyed. Within the same coral families across oceans, prevalence of unhealthy colonies was higher and some diseases were more common at sites in the Caribbean than those in the Pacific. The effects of high disease prevalence are potentially extensive given that the most affected coral families, the acroporids, faviids and siderastreids, are among the major reef-builders at these sites. The poritids and agaricids stood out in the Caribbean as being the most resistant to disease, even though these families were abundant in our surveys. Regional warm temperature anomalies were strongly correlated with high disease prevalence. The levels of disease reported here will provide a much-needed local reference point against which to compare future change.

Chronic nutrient enrichment increases prevalence and severity of coral disease and bleaching.

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Vega Thurber, Rebecca L; Burkepile, Deron E; Fuchs, Corinne; Shantz, Andrew A; McMinds, Ryan; Zaneveld, Jesse R

2014-02-01

Nutrient loading is one of the strongest drivers of marine habitat degradation. Yet, the link between nutrients and disease epizootics in marine organisms is often tenuous and supported only by correlative data. Here, we present experimental evidence that chronic nutrient exposure leads to increases in both disease prevalence and severity and coral bleaching in scleractinian corals, the major habitat-forming organisms in tropical reefs. Over 3 years, from June 2009 to June 2012, we continuously exposed areas of a coral reef to elevated levels of nitrogen and phosphorus. At the termination of the enrichment, we surveyed over 1200 scleractinian corals for signs of disease or bleaching. Siderastrea siderea corals within enrichment plots had a twofold increase in both the prevalence and severity of disease compared with corals in unenriched control plots. In addition, elevated nutrient loading increased coral bleaching; Agaricia spp. of corals exposed to nutrients suffered a 3.5-fold increase in bleaching frequency relative to control corals, providing empirical support for a hypothesized link between nutrient loading and bleaching-induced coral declines. However, 1 year later, after nutrient enrichment had been terminated for 10 months, there were no differences in coral disease or coral bleaching prevalence between the previously enriched and control treatments. Given that our experimental enrichments were well within the ranges of ambient nutrient concentrations found on many degraded reefs worldwide, these data provide strong empirical support to the idea that coastal nutrient loading is one of the major factors contributing to the increasing levels of both coral disease and coral bleaching. Yet, these data also suggest that simple improvements to water quality may be an effective way to mitigate some coral disease epizootics and the corresponding loss of coral cover in the future. © 2013 John Wiley & Sons Ltd.

Hawaiʻi Coral Disease database (HICORDIS: species-specific coral health data from across the Hawaiian archipelago

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Jamie M. Caldwell

2016-09-01

Full Text Available The Hawaiʻi Coral Disease database (HICORDIS houses data on colony-level coral health condition observed across the Hawaiian archipelago, providing information to conduct future analyses on coral reef health in an era of changing environmental conditions. Colonies were identified to the lowest taxonomic classification possible (species or genera, measured and assessed for visual signs of health condition. Data were recorded for 286,071 coral colonies surveyed on 1819 transects at 660 sites between 2005 and 2015. The database contains observations for 60 species from 22 genera with 21 different health conditions. The goals of the HICORDIS database are to: i provide open access, quality controlled and validated coral health data assembled from disparate surveys conducted across Hawaiʻi; ii facilitate appropriate crediting of data; and iii encourage future analyses of coral reef health. In this article, we describe and provide data from the HICORDIS database. The data presented in this paper were used in the research article “Satellite SST-based Coral Disease Outbreak Predictions for the Hawaiian Archipelago” (Caldwell et al., 2016 [1]. Keywords: Marine biology, Coral, Reefs, Disease, Hawaii

Biomedical and veterinary science can increase our understanding of coral disease

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Work, Thierry M.; Richardson, Laurie L.; Reynolds, T.L.; Willis, Bette L.

2008-01-01

A balanced approach to coral disease investigation is critical for understanding the global decline of corals. Such an approach should involve the proper use of biomedical concepts, tools, and terminology to address confusion and promote clarity in the coral disease literature. Investigating disease in corals should follow a logical series of steps including identification of disease, systematic morphologic descriptions of lesions at the gross and cellular levels, measurement of health indices, and experiments to understand disease pathogenesis and the complex interactions between host, pathogen, and the environment. This model for disease investigation is widely accepted in the medical, veterinary and invertebrate pathology disciplines. We present standard biomedical rationale behind the detection, description, and naming of diseases and offer examples of the application of Koch's postulates to elucidate the etiology of some infectious diseases. Basic epidemiologic concepts are introduced to help investigators think systematically about the cause(s) of complex diseases. A major goal of disease investigation in corals and other organisms is to gather data that will enable the establishment of standardized case definitions to distinguish among diseases. Concepts and facts amassed from empirical studies over the centuries by medical and veterinary pathologists have standardized disease investigation and are invaluable to coral researchers because of the robust comparisons they enable; examples of these are given throughout this paper. Arguments over whether coral diseases are caused by primary versus opportunistic pathogens reflect the lack of data available to prove or refute such hypotheses and emphasize the need for coral disease investigations that focus on: characterizing the normal microbiota and physiology of the healthy host; defining ecological interactions within the microbial community associated with the host; and investigating host immunity, host

A Framework for Responding to Coral Disease Outbreaks that Facilitates Adaptive Management

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Beeden, Roger; Maynard, Jeffrey A.; Marshall, Paul A.; Heron, Scott F.; Willis, Bette L.

2012-01-01

Predicted increases in coral disease outbreaks associated with climate change have implications for coral reef ecosystems and the people and industries that depend on them. It is critical that coral reef managers understand these implications and have the ability to assess and reduce risk, detect and contain outbreaks, and monitor and minimise impacts. Here, we present a coral disease response framework that has four core components: (1) an early warning system, (2) a tiered impact assessment program, (3) scaled management actions and (4) a communication plan. The early warning system combines predictive tools that monitor the risk of outbreaks of temperature-dependent coral diseases with in situ observations provided by a network of observers who regularly report on coral health and reef state. Verified reports of an increase in disease prevalence trigger a tiered response of more detailed impact assessment, targeted research and/or management actions. The response is scaled to the risk posed by the outbreak, which is a function of the severity and spatial extent of the impacts. We review potential management actions to mitigate coral disease impacts and facilitate recovery, considering emerging strategies unique to coral disease and more established strategies to support reef resilience. We also describe approaches to communicating about coral disease outbreaks that will address common misperceptions and raise awareness of the coral disease threat. By adopting this framework, managers and researchers can establish a community of practice and can develop response plans for the management of coral disease outbreaks based on local needs. The collaborations between managers and researchers we suggest will enable adaptive management of disease impacts following evaluating the cost-effectiveness of emerging response actions and incrementally improving our understanding of outbreak causation.

Identification of Antipathogenic Bacterial Coral Symbionts Against Porites Ulcerative White Spots Disease

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Sa'adah, Nor; Sabdono, Agus; Diah Permata Wijayanti, dan

2018-02-01

Coral reef ecosystems are ecosystems that are vulnerable and susceptible to damage due to the exploitation of ocean resources. One of the factors that cause coral damage is the disease that attacks the coral. Porites Ulcerative White Spots (PUWS) is a coral disease found in Indonesia and attacks the coral genera Porites allegedly caused by pathogenic microbial attacks. The purpose of this study was to identify the symbiotic bacteria on healthy coral that have antipatogenic potency against PUWS. The method used in this research was descriptive explorative. Sampling was done in Kemujan Island, Karimunjawa. Bacteria were isolated from healthy coral and coral affected by PUWS disease. Streak method was used to purify coral bacteria, while overlay and agar diffusion were used to test antipathogenic activity. Bacterial identification was carried out based on polyphasic approach. The results of this study showed that coral bacterial symbionts have antipathogenic activity against PUWS disease. The selected bacteria NM 1.2, NM 1.3 and KPSH 5. NM1.2 were closely related to Pseudoalteromonas piscicida, Pseudoalteromonas flavipulchra and Bacillus flexus, respectively.

How microbial community composition regulates coral disease development.

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Justin Mao-Jones

2010-03-01

Full Text Available Reef coral cover is in rapid decline worldwide, in part due to bleaching (expulsion of photosynthetic symbionts and outbreaks of infectious disease. One important factor associated with bleaching and in disease transmission is a shift in the composition of the microbial community in the mucus layer surrounding the coral: the resident microbial community-which is critical to the healthy functioning of the coral holobiont-is replaced by pathogenic microbes, often species of Vibrio. In this paper we develop computational models for microbial community dynamics in the mucus layer in order to understand how the surface microbial community responds to changes in environmental conditions, and under what circumstances it becomes vulnerable to overgrowth by pathogens. Some of our model's assumptions and parameter values are based on Vibrio spp. as a model system for other established and emerging coral pathogens. We find that the pattern of interactions in the surface microbial community facilitates the existence of alternate stable states, one dominated by antibiotic-producing beneficial microbes and the other pathogen-dominated. A shift to pathogen dominance under transient stressful conditions, such as a brief warming spell, may persist long after environmental conditions have returned to normal. This prediction is consistent with experimental findings that antibiotic properties of Acropora palmata mucus did not return to normal long after temperatures had fallen. Long-term loss of antibiotic activity eliminates a critical component in coral defense against disease, giving pathogens an extended opportunity to infect and spread within the host, elevating the risk of coral bleaching, disease, and mortality.

How microbial community composition regulates coral disease development.

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Mao-Jones, Justin; Ritchie, Kim B; Jones, Laura E; Ellner, Stephen P

2010-03-30

Reef coral cover is in rapid decline worldwide, in part due to bleaching (expulsion of photosynthetic symbionts) and outbreaks of infectious disease. One important factor associated with bleaching and in disease transmission is a shift in the composition of the microbial community in the mucus layer surrounding the coral: the resident microbial community-which is critical to the healthy functioning of the coral holobiont-is replaced by pathogenic microbes, often species of Vibrio. In this paper we develop computational models for microbial community dynamics in the mucus layer in order to understand how the surface microbial community responds to changes in environmental conditions, and under what circumstances it becomes vulnerable to overgrowth by pathogens. Some of our model's assumptions and parameter values are based on Vibrio spp. as a model system for other established and emerging coral pathogens. We find that the pattern of interactions in the surface microbial community facilitates the existence of alternate stable states, one dominated by antibiotic-producing beneficial microbes and the other pathogen-dominated. A shift to pathogen dominance under transient stressful conditions, such as a brief warming spell, may persist long after environmental conditions have returned to normal. This prediction is consistent with experimental findings that antibiotic properties of Acropora palmata mucus did not return to normal long after temperatures had fallen. Long-term loss of antibiotic activity eliminates a critical component in coral defense against disease, giving pathogens an extended opportunity to infect and spread within the host, elevating the risk of coral bleaching, disease, and mortality.

Coral disease following massive bleaching in 2005 causes 60% decline in coral cover on reefs in the US Virgin Islands

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Miller, J.; Muller, E.; Rogers, C.; Waara, R.; Atkinson, A.; Whelan, K.R.T.; Patterson, M.; Witcher, B.

2009-01-01

In the northeast Caribbean, doldrum-like conditions combined with elevated water temperatures in the summer/fall 2005 created the most severe coral bleaching event ever documented within this region. Video monitoring of 100 randomly chosen, permanent transects at five study sites in the US Virgin Islands revealed over 90% of the scleractinian coral cover showed signs of thermal stress by paling or becoming completely white. Lower water temperatures in October allowed some re-coloring of corals; however, a subsequent unprecedented regional outbreak of coral disease affected all sites. Five known diseases or syndromes were recorded; however, most lesions showed signs similar to white plague. Nineteen scleractinian species were affected by disease, with >90% of the disease-induced lesions occurring on the genus Montastraea. The disease outbreak peaked several months after the onset of bleaching at all sites but did not occur at the same time. The mean number of disease-induced lesions increased 51-fold and the mean area of disease-associated mortality increased 13-fold when compared with pre-bleaching disease levels. In the 12 months following the onset of bleaching, coral cover declined at all sites (average loss: 51.5%, range: 42.4-61.8%) reducing the five-site average from 21.4% before bleaching to 10.3% with most mortality caused by white plague disease, not bleaching. Continued losses through October 2007 reduced the average coral cover of the five sites to 8.3% (average 2-year loss: 61.1%, range: 53.0-79.3%). Mean cover by M. annularis (complex) decreased 51%, Colpophyllia natans 78% and Agaricia agaricites 87%. Isolated disease outbreaks have been documented before in the Virgin Islands, but never as widespread or devastating as the one that occurred after the 2005 Caribbean coral-bleaching event. This study provides insight into the effects of continued seawater warming and subsequent coral bleaching events in the Caribbean and highlights the need to

Viruses: agents of coral disease?

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Davy, S K; Burchett, S G; Dale, A L; Davies, P; Davy, J E; Muncke, C; Hoegh-Guldberg, O; Wilson, W H

2006-03-23

The potential role of viruses in coral disease has only recently begun to receive attention. Here we describe our attempts to determine whether viruses are present in thermally stressed corals Pavona danai, Acropora formosa and Stylophora pistillata and zoanthids Zoanthus sp., and their zooxanthellae. Heat-shocked P. danai, A. formosa and Zoanthus sp. all produced numerous virus-like particles (VLPs) that were evident in the animal tissue, zooxanthellae and the surrounding seawater; VLPs were also seen around heat-shocked freshly isolated zooxanthellae (FIZ) from P. danai and S. pistillata. The most commonly seen VLPs were tail-less, hexagonal and about 40 to 50 nm in diameter, though a diverse range of other VLP morphotypes (e.g. rounded, rod-shaped, droplet-shaped, filamentous) were also present around corals. When VLPs around heat-shocked FIZ from S. pistillata were added to non-stressed FIZ from this coral, they resulted in cell lysis, suggesting that an infectious agent was present; however, analysis with transmission electron microscopy provided no clear evidence of viral infection. The release of diverse VLPs was again apparent when flow cytometry was used to enumerate release by heat-stressed A. formosa nubbins. Our data support the infection of reef corals by viruses, though we cannot yet determine the precise origin (i.e. coral, zooxanthellae and/or surface microbes) of the VLPs seen. Furthermore, genome sequence data are required to establish the presence of viruses unequivocally.

Multiple mechanisms of transmission of the Caribbean coral disease white plague

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Clemens, E.; Brandt, M. E.

2015-12-01

White plague is one of the most devastating coral diseases in the Caribbean, and yet important aspects of its epidemiology, including how the disease transmits, remain unknown. This study tested potential mechanisms and rates of transmission of white plague in a laboratory setting. Transmission mechanisms including the transport of water, contact with macroalgae, and predation via corallivorous worms and snails were tested on the host species Orbicella annularis. Two of the tested mechanisms were shown to transmit disease: water transport and the corallivorous snail Coralliophila abbreviata. Between these transmission mechanisms, transport of water between a diseased coral and a healthy coral resulted in disease incidence significantly more frequently in exposed healthy corals. Transmission via water transport also occurred more quickly and was associated with higher rates of tissue loss (up to 3.5 cm d-1) than with the corallivorous snail treatment. In addition, water that was in contact with diseased corals but was filtered with a 0.22-μm filter prior to being introduced to apparently healthy corals also resulted in the transmission of disease signs, but at a much lower rate than when water was not filtered. This study has provided important information on the transmission potential of Caribbean white plague disease and highlights the need for a greater understanding of how these processes operate in the natural environment.

Patterns of coral disease across the Hawaiian archipelago: relating disease to environment.

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Greta S Aeby

Full Text Available 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 Por

Patterns of coral disease across the Hawaiian Archipelago: Relating disease to environment

Science.gov (United States)

Aeby, G.S.; Williams, G.J.; Franklin, E.C.; Kenyon, J.; Cox, E.F.; Coles, S.; Work, Thierry 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

Link between sewage-derived nitrogen pollution and coral disease severity in Guam

International Nuclear Information System (INIS)

Redding, Jamey E.; Myers-Miller, Roxanna L.; Baker, David M.; Fogel, Marilyn; Raymundo, Laurie J.; Kim, Kiho

2013-01-01

Highlights: • We evaluated sources of nitrogen pollution in coastal waters of Guam. • Stable isotope analyses showed the dominance of sewage-derived nitrogen. • Nitrogen inputs correlated with coral disease severity. • Planned population increase on Guam will exacerbate impact of coral diseases. -- Abstract: The goals of this study were to evaluate the contribution of sewage-derived N to reef flat communities in Guam and to assess the impact of N inputs on coral disease. We used stable isotope analysis of macroalgae and a soft coral, sampled bimonthly, as a proxy for N dynamics, and surveyed Porites spp., a dominant coral taxon on Guam’s reefs, for white syndrome disease severity. Results showed a strong influence of sewage-derived N in nearshore waters, with δ 15 N values varying as a function of species sampled, site, and sampling date. Increases in sewage-derived N correlated significantly with increases in the severity of disease among Porites spp., with δ 15 N values accounting for more than 48% of the variation in changes in disease severity. The anticipated military realignment and related population increase in Guam are expected to lead to increased white syndrome infections and other coral diseases

ROLE OF CORAL DISEASES AND ANTHROPOGENIC STRESSORS ON TROPIC MARINE CORAL REEFS

Science.gov (United States)

Stony (scleractinian) and soft (octocorals) corals throughout the Western Atlantic have been affected by several fatal diseases in the last two decades. In many locations the communities have not recovered from these diseases and the ecosystem has permanently changed. Several hyp...

Temporal Sampling of White Band Disease Infected Corals Reveals Complex and Dynamic Bacterial Communities

Science.gov (United States)

Gignoux-Wolfsohn, S.; Vollmer, S. V.; Aronson, F. M.

2016-02-01

White band disease (WBD) is a coral disease that is currently decimating populations of the endangered staghorn coral, Acropora cervicornis and elkhorn coral, A. palmata across the Caribbean. Since it was first reported in 1979, WBD has killed 95% of these critical reef-building Caribbean corals. WBD is infectious; it can be transmitted through the water column or by a corallivorous snail. While previous research shows that WBD is likely caused by bacteria, identification of a specific pathogen or pathogens has remained elusive. Much of the difficulty of understanding the etiology of the disease comes from a lack of information about how existing bacterial communities respond to disease and separating initial from secondary colonizers. In order to address this lack of information, we performed a fully-crossed tank infection experiment. We exposed healthy corals from two different sites to disease and healthy (control) homogenates from both sites, replicating genotype across tanks. We sampled every coral at three time points: before inoculation with the homogenate, after inoculation, and when the coral showed signs of disease. We then performed 16S rRNA gene sequencing on the Illumina HiSeq 2000. We saw significant differences between time points and disease state. Interestingly, at the first time point (time one) we observed differences between genotypes: every fragment from some genotypes was dominated by Endozoicomonas, while other genotypes were not dominated by one family. At time two we saw an increase in abundance of Alteromonadaceae and Flavobacteriaceae in all corals, and a larger increase in disease-exposed corals. At time three, we saw another increase in Flavobacteriaceae abundance in diseased corals, as well as an introduction of Francisella to diseased corals. While Flavobacteriaceae and Francisella were proposed as potential pathogens, their increase at time three suggests they may be secondary colonizers or opportunists. In genotypes that were

Genetic Signature of Resistance to White Band Disease in the Caribbean Staghorn Coral Acropora cervicornis.

Directory of Open Access Journals (Sweden)

Silvia Libro

Full Text Available Coral reefs are declining worldwide due to multiple factors including rising sea surface temperature, ocean acidification, and disease outbreaks. Over the last 30 years, White Band Disease (WBD alone has killed up to 95% of the Caribbean`s dominant shallow-water corals--the staghorn coral Acropora cervicornis and the elkhorn coral A. palmata. Both corals are now listed on the US Endangered Species Act, and while their recovery has been slow, recent transmission surveys indicate that more than 5% of staghorn corals are disease resistant. Here we compared transcriptome-wide gene expression between resistant and susceptible staghorn corals exposed to WBD using in situ transmission assays. We identified constitutive gene expression differences underlying disease resistance that are independent from the immune response associated with disease exposure. Genes involved in RNA interference-mediated gene silencing, including Argonaute were up-regulated in resistant corals, whereas heat shock proteins (HSPs were down-regulated. Up-regulation of Argonaute proteins indicates that post-transcriptional gene silencing plays a key, but previously unsuspected role in coral immunity and disease resistance. Constitutive expression of HSPs has been linked to thermal resilience in other Acropora corals, suggesting that the down-regulation of HSPs in disease resistant staghorn corals may confer a dual benefit of thermal resilience.

Genetic Signature of Resistance to White Band Disease in the Caribbean Staghorn Coral Acropora cervicornis.

Science.gov (United States)

Libro, Silvia; Vollmer, Steven V

2016-01-01

Coral reefs are declining worldwide due to multiple factors including rising sea surface temperature, ocean acidification, and disease outbreaks. Over the last 30 years, White Band Disease (WBD) alone has killed up to 95% of the Caribbean`s dominant shallow-water corals--the staghorn coral Acropora cervicornis and the elkhorn coral A. palmata. Both corals are now listed on the US Endangered Species Act, and while their recovery has been slow, recent transmission surveys indicate that more than 5% of staghorn corals are disease resistant. Here we compared transcriptome-wide gene expression between resistant and susceptible staghorn corals exposed to WBD using in situ transmission assays. We identified constitutive gene expression differences underlying disease resistance that are independent from the immune response associated with disease exposure. Genes involved in RNA interference-mediated gene silencing, including Argonaute were up-regulated in resistant corals, whereas heat shock proteins (HSPs) were down-regulated. Up-regulation of Argonaute proteins indicates that post-transcriptional gene silencing plays a key, but previously unsuspected role in coral immunity and disease resistance. Constitutive expression of HSPs has been linked to thermal resilience in other Acropora corals, suggesting that the down-regulation of HSPs in disease resistant staghorn corals may confer a dual benefit of thermal resilience.

Corals hosting symbiotic hydrozoans are less susceptible to predation and disease

KAUST Repository

Montano, Simone

2017-12-20

In spite of growing evidence that climate change may dramatically affect networks of interacting species, whether-and to what extent-ecological interactions can mediate species\\' responses to disturbances is an open question. Here we show how a largely overseen association such as that between hydrozoans and scleractinian corals could be possibly associated with a reduction in coral susceptibility to ever-increasing predator and disease outbreaks. We examined 2455 scleractinian colonies (from both Maldivian and the Saudi Arabian coral reefs) searching for non-random patterns in the occurrence of hydrozoans on corals showing signs of different health conditions (i.e. bleaching, algal overgrowth, corallivory and different coral diseases). We show that, after accounting for geographical, ecological and co-evolutionary factors, signs of disease and corallivory are significantly lower in coral colonies hosting hydrozoans than in hydrozoan-free ones. This finding has important implications for our understanding of the ecology of coral reefs, and for their conservation in the current scenario of global change, because it suggests that symbiotic hydrozoans may play an active role in protecting their scleractinian hosts from stresses induced by warming water temperatures.

Direct and indirect effects of a new disease of alcyonacean soft corals

Science.gov (United States)

Slattery, M.; Renegar, D. A.; Gochfeld, D. J.

2013-09-01

Alcyonacean soft corals form major components of the biomass and biodiversity on many shallow Indo-Pacific reefs. In spite of the observed increase in marine diseases worldwide, disease has rarely been reported from this taxonomic group. Here, we describe a chronic tissue loss disease affecting soft corals of the genus Sinularia on reefs in Guam. The disease presents as a diffuse wrinkling of the otherwise smooth fingers, followed by tissue sloughing, necrosis, and disintegration. Until a cause has been confirmed, we propose the name Sinularia Tissue Loss Disease. This disease was first observed at low prevalence (Disease prevalence is now significantly greater in the hybrid (11-12 %) than in either parent species (2-3 %). Histological examination of healthy and affected tissues of hybrid soft corals demonstrates a loss of structural integrity, increased densities of amoebocytes and inclusion of unidentified foreign eukaryotic cells that resemble oocysts, in the diseased tissues. The presence of disease is associated with reduced concentrations of cellular protein levels, although lipids and carbohydrates were unaffected. Results from a common garden transplant experiment indicate that disease also has an indirect effect on hybrid soft corals by increasing rates of butterflyfish predation over the levels found on healthy hybrids or on healthy and diseased parent species. Our results indicate that interactions between the parent and hybrid soft coral populations are more dynamic than previously reported. Loss of hybrid soft corals on already degraded back-reefs of Guam could have significant repercussions for these reef communities.

Sediment and turbidity associated with offshore dredging increase coral disease prevalence on nearby reefs.

Science.gov (United States)

Pollock, F Joseph; Lamb, Joleah B; Field, Stuart N; Heron, Scott F; Schaffelke, Britta; Shedrawi, George; Bourne, David G; Willis, Bette L

2014-01-01

In recent decades, coral reef ecosystems have declined to the extent that reefs are now threatened globally. While many water quality parameters have been proposed to contribute to reef declines, little evidence exists conclusively linking specific water quality parameters with increased disease prevalence in situ. Here we report evidence from in situ coral health surveys confirming that chronic exposure to dredging-associated sediment plumes significantly increase the prevalence of white syndromes, a devastating group of globally important coral diseases. Coral health surveys were conducted along a dredging-associated sediment plume gradient to assess the relationship between sedimentation, turbidity and coral health. Reefs exposed to the highest number of days under the sediment plume (296 to 347 days) had two-fold higher levels of disease, largely driven by a 2.5-fold increase in white syndromes, and a six-fold increase in other signs of compromised coral health relative to reefs with little or no plume exposure (0 to 9 days). Multivariate modeling and ordination incorporating sediment exposure level, coral community composition and cover, predation and multiple thermal stress indices provided further confirmation that sediment plume exposure level was the main driver of elevated disease and other compromised coral health indicators. This study provides the first evidence linking dredging-associated sedimentation and turbidity with elevated coral disease prevalence in situ. Our results may help to explain observed increases in global coral disease prevalence in recent decades and suggest that minimizing sedimentation and turbidity associated with coastal development will provide an important management tool for controlling coral disease epizootics.

Disease and stress-induced mortality of corals in Indian reefs and observations on bleaching of corals in the Andamans

Digital Repository Service at National Institute of Oceanography (India)

Ravindran, J.; Raghukumar, C.; Raghukumar, S.

A study was carried out in the Lakshadweep and Andaman islands and the Gulf of Kutch to assess the health of corals in Indian reefs. Disease, predation and stress were the major factors of coral mortality. Death caused by diseases - the black band...

RNA-Seq of the Caribbean reef-building coral Orbicella faveolata (Scleractinia-Merulinidae under bleaching and disease stress expands models of coral innate immunity

Directory of Open Access Journals (Sweden)

David A. Anderson

2016-02-01

Full Text Available Climate change-driven coral disease outbreaks have led to widespread declines in coral populations. Early work on coral genomics established that corals have a complex innate immune system, and whole-transcriptome gene expression studies have revealed mechanisms by which the coral immune system responds to stress and disease. The present investigation expands bioinformatic data available to study coral molecular physiology through the assembly and annotation of a reference transcriptome of the Caribbean reef-building coral, Orbicella faveolata. Samples were collected during a warm water thermal anomaly, coral bleaching event and Caribbean yellow band disease outbreak in 2010 in Puerto Rico. Multiplex sequencing of RNA on the Illumina GAIIx platform and de novo transcriptome assembly by Trinity produced 70,745,177 raw short-sequence reads and 32,463 O. faveolata transcripts, respectively. The reference transcriptome was annotated with gene ontologies, mapped to KEGG pathways, and a predicted proteome of 20,488 sequences was generated. Protein families and signaling pathways that are essential in the regulation of innate immunity across Phyla were investigated in-depth. Results were used to develop models of evolutionarily conserved Wnt, Notch, Rig-like receptor, Nod-like receptor, and Dicer signaling. O. faveolata is a coral species that has been studied widely under climate-driven stress and disease, and the present investigation provides new data on the genes that putatively regulate its immune system.

Contemporary white-band disease in Caribbean corals driven by climate change

Science.gov (United States)

Randall, C. J.; van Woesik, R.

2015-04-01

Over the past 40 years, two of the dominant reef-building corals in the Caribbean, Acropora palmata and Acropora cervicornis, have experienced unprecedented declines. That loss has been largely attributed to a syndrome commonly referred to as white-band disease. Climate change-driven increases in sea surface temperature (SST) have been linked to several coral diseases, yet, despite decades of research, the attribution of white-band disease to climate change remains unknown. Here we hindcasted the potential relationship between recent ocean warming and outbreaks of white-band disease on acroporid corals. We quantified eight SST metrics, including rates of change in SST and contemporary thermal anomalies, and compared them with records of white-band disease on A. palmata and A. cervicornis from 473 sites across the Caribbean, surveyed from 1997 to 2004. The results of our models suggest that decades-long climate-driven changes in SST, increases in thermal minima, and the breach of thermal maxima have all played significant roles in the spread of white-band disease. We conclude that white-band disease has been strongly coupled with thermal stresses associated with climate change, which has contributed to the regional decline of these once-dominant reef-building corals.

White plague-like coral disease in remote reefs of the Western Caribbean

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Juan A Sánchez

2010-05-01

Full Text Available The health of coral reef communities has been decreasing over the last 50 years, due the negative effects of human activities combined with other natural processes. We present documentation of a White Plague Disease (WPD outbreak in the Serrana Bank, an isolated Western Caribbean atoll with presumably inexistent pollutant inputs from local human settlements. In addition, this study summarizes seven years of observations on diseased corals in the nearby island of San Andrés, which in contrast is one of the most populated islands of the Caribbean. There was a massive coral mortality in the atoll lagoon (14°27’53.24", 80°14’22.27" W, and 12m depth due to WPD on May 4 of 2003. Seventeen species were found dead or largely affected by the disease. The information resulting from GPS and manta-tow transects revealed that approximately 5.8ha of reticulate Montastraea spp. patch reefs were lethally affected by the disease in the atoll. On May 8 of the same year we observed and calculated a mean coral cover of 7.03% (SD± 2.44, a mean diseased coral tissue cover of 5.5% (SD± 1.1 and a 13.4% (SD± 8.05 of recently dead coral covered with a thin filamentous algae layer; approximately 73% of mortalities caused by the disease occurred before the end of the outbreak. A rough estimate of 18.9% in recent coral cover reduction can be attributed to WPD. This represents about 82% of the total coral cover decline since 1995. Semi-enclosed environments such as atoll lagoons and the reticulate patch-reefs of Montastraea spp. seem to be particularly vulnerable to this kind of coral disease, which constitute an alert to increase the monitoring of the same kind of atoll environments. The WPD has been present in the area of the nearby island of San Andrés at a low prevalence level, with sporadic increasing peaks of disease proliferation. The peaks observed during 1999 and 2004 comprised increases of 266% and 355% respectively, suggesting an alarming progression of

Immunity to community: what can immune pathways tell us about disease patterns in corals?

Science.gov (United States)

Mydlarz, L. D.; Fuess, L.; Pinzon, J. C.; Weil, E.

2016-02-01

Predicting species composition and abundances is one of the most fundamental questions in ecology. This question is even more pressing in marine ecology and coral reefs since communities are changing at a rapid pace due to climate-related changes. Increases in disease prevalence and severity are just some of the consequences of these environmental changes. Particularly in coral reef ecosystems, diseases are increasing and driving region-wide population collapses. It has become clear, however, that not all reefs or coral species are affected by disease equally. In fact, the Caribbean is a concentrated area for diseases. The patterns in which disease manifests itself on an individual reef are also proving interesting, as not all coral species are affected by disease equally. Some species are host to different diseases, but seem to successfully fight them reducing mortality. Other species are disproportionately infected on any given reef and experience high mortality due to disease. We are interested in the role immunity can play in directing these patterns and are evaluating coral immunity using several novel approaches. We exposed 4 species of corals with different disease susceptibilities to immune stimulators and quantified of coral immunity using a combination of full transcriptome sequencing and protein activity assays for gene to phenotype analysis. We also mapped gene expression changes onto immune pathways (i.e. melanin-cascade, antimicrobial peptide synthesis, complement cascade, lectin-opsonization) to evaluate expression of immune pathways between species. In our preliminary data we found many immune genes in the disease susceptible Orbicella faveolata underwent changes in gene expression opposite of the predictions and may disply `dysfunctional' patterns of expression. We will present expression data for 4 species of coral and assess how these transcriptional and protein immune responses are related to disease susceptibility in nature, thus scaling up

Distributed Database Access in the LHC Computing Grid with CORAL

CERN Document Server

Molnár, Z; Düllmann, D; Giacomo, G; Kalkhof, A; Valassi, A; CERN. Geneva. IT Department

2009-01-01

The CORAL package is the LCG Persistency Framework foundation for accessing relational databases. From the start CORAL has been designed to facilitate the deployment of the LHC experiment database applications in a distributed computing environment. In particular we cover - improvements to database service scalability by client connection management - platform-independent, multi-tier scalable database access by connection multiplexing, caching - a secure authentication and authorisation scheme integrated with existing grid services. We will summarize the deployment experience from several experiment productions using the distributed database infrastructure, which is now available in LCG. Finally, we present perspectives for future developments in this area.

Assessing the Effects of Disease and Bleaching on Florida Keys Corals by Fitting Population Models to Data

Science.gov (United States)

Coral diseases have increased in frequency over the past few decades and have important influences on the structure and composition of coral reef communities. However, there is limited information on the etiologies of many coral diseases, and pathways via which coral diseases ar...

Modeling the Impact of White-Plague Coral Disease in Climate Change Scenarios.

Directory of Open Access Journals (Sweden)

Assaf Zvuloni

2015-06-01

Full Text Available Coral reefs are in global decline, with coral diseases increasing both in prevalence and in space, a situation that is expected only to worsen as future thermal stressors increase. Through intense surveillance, we have collected a unique and highly resolved dataset from the coral reef of Eilat (Israel, Red Sea, that documents the spatiotemporal dynamics of a White Plague Disease (WPD outbreak over the course of a full season. Based on modern statistical methodologies, we develop a novel spatial epidemiological model that uses a maximum-likelihood procedure to fit the data and assess the transmission pattern of WPD. We link the model to sea surface temperature (SST and test the possible effect of increasing temperatures on disease dynamics. Our results reveal that the likelihood of a susceptible coral to become infected is governed both by SST and by its spatial location relative to nearby infected corals. The model shows that the magnitude of WPD epidemics strongly depends on demographic circumstances; under one extreme, when recruitment is free-space regulated and coral density remains relatively constant, even an increase of only 0.5°C in SST can cause epidemics to double in magnitude. In reality, however, the spatial nature of transmission can effectively protect the community, restricting the magnitude of annual epidemics. This is because the probability of susceptible corals to become infected is negatively associated with coral density. Based on our findings, we expect that infectious diseases having a significant spatial component, such as Red-Sea WPD, will never lead to a complete destruction of the coral community under increased thermal stress. However, this also implies that signs of recovery of local coral communities may be misleading; indicative more of spatial dynamics than true rehabilitation of these communities. In contrast to earlier generic models, our approach captures dynamics of WPD both in space and time, accounting for

Human pathogen shown to cause disease in the threatened eklhorn coral Acropora palmata.

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Kathryn Patterson Sutherland

Full Text Available Coral reefs are in severe decline. Infections by the human pathogen Serratia marcescens have contributed to precipitous losses in the common Caribbean elkhorn coral, Acropora palmata, culminating in its listing under the United States Endangered Species Act. During a 2003 outbreak of this coral disease, called acroporid serratiosis (APS, a unique strain of the pathogen, Serratia marcescens strain PDR60, was identified from diseased A. palmata, human wastewater, the non-host coral Siderastrea siderea and the corallivorous snail Coralliophila abbreviata. In order to examine humans as a source and other marine invertebrates as vectors and/or reservoirs of the APS pathogen, challenge experiments were conducted with A. palmata maintained in closed aquaria to determine infectivity of strain PDR60 from reef and wastewater sources. Strain PDR60 from wastewater and diseased A. palmata caused disease signs in elkhorn coral in as little as four and five days, respectively, demonstrating that wastewater is a definitive source of APS and identifying human strain PDR60 as a coral pathogen through fulfillment of Koch's postulates. A. palmata inoculated with strain PDR60 from C. abbreviata showed limited virulence, with one of three inoculated fragments developing APS signs within 13 days. Strain PDR60 from non-host coral S. siderea showed a delayed pathogenic effect, with disease signs developing within an average of 20 days. These results suggest that C. abbreviata and non-host corals may function as reservoirs or vectors of the APS pathogen. Our results provide the first example of a marine "reverse zoonosis" involving the transmission of a human pathogen (S. marcescens to a marine invertebrate (A. palmata. These findings underscore the interaction between public health practices and environmental health indices such as coral reef survival.

Human pathogen shown to cause disease in the threatened eklhorn coral Acropora palmata.

Science.gov (United States)

Sutherland, Kathryn Patterson; Shaban, Sameera; Joyner, Jessica L; Porter, James W; Lipp, Erin K

2011-01-01

Coral reefs are in severe decline. Infections by the human pathogen Serratia marcescens have contributed to precipitous losses in the common Caribbean elkhorn coral, Acropora palmata, culminating in its listing under the United States Endangered Species Act. During a 2003 outbreak of this coral disease, called acroporid serratiosis (APS), a unique strain of the pathogen, Serratia marcescens strain PDR60, was identified from diseased A. palmata, human wastewater, the non-host coral Siderastrea siderea and the corallivorous snail Coralliophila abbreviata. In order to examine humans as a source and other marine invertebrates as vectors and/or reservoirs of the APS pathogen, challenge experiments were conducted with A. palmata maintained in closed aquaria to determine infectivity of strain PDR60 from reef and wastewater sources. Strain PDR60 from wastewater and diseased A. palmata caused disease signs in elkhorn coral in as little as four and five days, respectively, demonstrating that wastewater is a definitive source of APS and identifying human strain PDR60 as a coral pathogen through fulfillment of Koch's postulates. A. palmata inoculated with strain PDR60 from C. abbreviata showed limited virulence, with one of three inoculated fragments developing APS signs within 13 days. Strain PDR60 from non-host coral S. siderea showed a delayed pathogenic effect, with disease signs developing within an average of 20 days. These results suggest that C. abbreviata and non-host corals may function as reservoirs or vectors of the APS pathogen. Our results provide the first example of a marine "reverse zoonosis" involving the transmission of a human pathogen (S. marcescens) to a marine invertebrate (A. palmata). These findings underscore the interaction between public health practices and environmental health indices such as coral reef survival.

Genetic susceptibility, colony size, and water temperature drive white-pox disease on the coral Acropora palmata.

Science.gov (United States)

Muller, Erinn M; van Woesik, Robert

2014-01-01

Outbreaks of coral diseases are one of the greatest threats to reef corals in the Caribbean, yet the mechanisms that lead to coral diseases are still largely unknown. Here we examined the spatial-temporal dynamics of white-pox disease on Acropora palmata coral colonies of known genotypes. We took a Bayesian approach, using Integrated Nested Laplace Approximation algorithms, to examine which covariates influenced the presence of white-pox disease over seven years. We showed that colony size, genetic susceptibility of the coral host, and high-water temperatures were the primary tested variables that were positively associated with the presence of white-pox disease on A. palmata colonies. Our study also showed that neither distance from previously diseased individuals, nor colony location, influenced the dynamics of white-pox disease. These results suggest that white-pox disease was most likely a consequence of anomalously high water temperatures that selectively compromised the oldest colonies and the most susceptible coral genotypes.

Genetic susceptibility, colony size, and water temperature drive white-pox disease on the coral Acropora palmata.

Directory of Open Access Journals (Sweden)

Erinn M Muller

Full Text Available Outbreaks of coral diseases are one of the greatest threats to reef corals in the Caribbean, yet the mechanisms that lead to coral diseases are still largely unknown. Here we examined the spatial-temporal dynamics of white-pox disease on Acropora palmata coral colonies of known genotypes. We took a Bayesian approach, using Integrated Nested Laplace Approximation algorithms, to examine which covariates influenced the presence of white-pox disease over seven years. We showed that colony size, genetic susceptibility of the coral host, and high-water temperatures were the primary tested variables that were positively associated with the presence of white-pox disease on A. palmata colonies. Our study also showed that neither distance from previously diseased individuals, nor colony location, influenced the dynamics of white-pox disease. These results suggest that white-pox disease was most likely a consequence of anomalously high water temperatures that selectively compromised the oldest colonies and the most susceptible coral genotypes.

Ecological aspects of the distribution of reef corals in the Netherlands Antilles

NARCIS (Netherlands)

Bak, Rolf P.M.

1975-01-01

The vertical and horizontal patterns of the distribution of corals and coral reefs (to a depth of 90 m) are discussed in relation to the environmental factors: geomorphology of the bottom, available substrate, light, turbidity, sedimentation, water movement and temperature. There is a general

A survey of cellular reactions to environmental stress and disease in Caribbean scleractinian corals

Science.gov (United States)

Peters, Esther C.

1984-03-01

Despite growing concern about the demise of coral reefs in many areas of the world, few studies have investigated the possibility that bacteria- or virus-caused diseases may be important agents in the disappearance of living coral tissue from reefs, and that their occurrence and transmission may be influenced by natural or man-made changes in water quality, particularly increased sedimentation and turbidity. One forereef site off St. Croix, U. S. Virgin Islands, and three shallow-water reef sites off Puerto Rico were examined for variations in coral composition, local environmental conditions, and the presence of possible diseases in the stony corals. Visual observations were supplemented with standard histopathological examination under the light microscope of tissues from 257 specimens (representing 9 genera and 13 species), along with additional samples obtained from the Netherlands Antilles, the Grenadines, the Florida Keys and the Smithsonian Coral Reef Microcosm. This procedure proved to be necessary to accurately determine the condition of the colony, to detect the presence of microorganisms, and to correlate tissue health and microparasite infestations with apparent symptoms. These lesions varied with the species and the site. For example, off Guayanilla Bay, three species showed increased or decreased mucosecretory cell development, and another exhibited an unusual microparasite, which may be related to the chronic sedimentation at this site. Although colonies of several species showed signs of “white band disease” at five locations, bacterial colonies composed of Gram-negative rods were present only in acroporid tissues from the relatively pristine St. Croix site and the Netherlands Antilles. The distribution and possible mode of occurrence of these and other diseases and microparasite infestations suggest that acute changes in microhabitat conditions or injuries to individual colonies may be as important to the development of some of these lesions as

Modeling the Impact of White-Plague Coral Disease in Climate Change Scenarios

NARCIS (Netherlands)

Zvuloni, A.; Artzy-Randrup, Y.; Katriel, G.; Loya, Y.; Stone, L.

2015-01-01

Coral reefs are in global decline, with coral diseases increasing both in prevalence and in space, a situation that is expected only to worsen as future thermal stressors increase. Through intense surveillance, we have collected a unique and highly resolved dataset from the coral reef of Eilat

Genetic Susceptibility, Colony Size, and Water Temperature Drive White-Pox Disease on the Coral Acropora palmata

OpenAIRE

Muller, Erinn M.; van Woesik, Robert

2014-01-01

Outbreaks of coral diseases are one of the greatest threats to reef corals in the Caribbean, yet the mechanisms that lead to coral diseases are still largely unknown. Here we examined the spatial-temporal dynamics of white-pox disease on Acropora palmata coral colonies of known genotypes. We took a Bayesian approach, using Integrated Nested Laplace Approximation algorithms, to examine which covariates influenced the presence of white-pox disease over seven years. We showed that colony size, g...

Analysis of the coral associated bacterial community structures in healthy and diseased corals from off-shore of southern Taiwan.

Science.gov (United States)

Chiou, Shu-Fen; Kuo, Jimmy; Wong, Tit-Yee; Fan, Tung-Yung; Tew, Kwee Siong; Liu, Jong-Kang

2010-07-01

The methods of denaturing gradient gel electrophoresis (DGGE) and DNA sequencing were used to analyze the ribotypes of microbial communities associated with corals. Both healthy and diseased coral of different species were collected at three locations off the southern coast of Taiwan. Ribotyping results suggested that the microbial communities were diverse. The microbial community profiles, even among the same species of corals from different geographical locations, differ significantly. The coral-associated bacterial communities contain many bacteria common to the habitants of various invertebrates. However, some bacteria were unexpected. The presence of some unusual species, such as Staphylococcus, Clostridium and Legionella, associated with corals that were likely the results of human activities. Human activities, such as thermal pollution from the nearby nuclear plant, active fishing and tourism industries in the region might have all contributed to the change in bacterial communities and the death of coral colonies around the region.

White plague disease outbreak in a coral reef at Los Roques National Park, Venezuela.

Science.gov (United States)

Croquer, Aldo; Pauls, Sheila M; Zubillaga, Ainhoa L

2003-06-01

Coral diseases have been reported as a major problem affecting Caribbean coral reefs. During August 2000, a coral mortality event of White Plague Disease-II (WPD-II) was observed at Madrizqui Reef in Los Roques National Park, Venezuela. This disease was identified as the major cause of coral mortality, affecting 24% of all colonies surveyed (n = 1 439). Other diseases such as Black Band Disease (BBD), Yellow Blotch Disease (YBD), Dark Spots Disease (DSD) and White Band Disease (WBD) were also recorded, but showed a lower incidence (0.14-0.97%). Two depth intervals, D1 (5.5-6.5 m) and D2 (9-9.5 m) were surveyed with two sets of three band transects 50 x 2 m long, placed parallel to the long axis of the reef. All healthy and injured corals, along each band transect, were counted and identified to species level. Additionally, all diseases and recent mortality that were still identifiable on each colony also were recorded. The incidence of colonies affected by WPD-II ranged from 12.8 to 33% among transects, where thirteen species of scleractinian corals showed several degrees of mortality. The species most affected were Montastraea annularis (39.13%), M. faveolata (26.67%), M. franksi (9.86%), Stephanocoenia intersepta (7.25%), Colpophyllia natans (6.96%), Diploria labyrinthiformis (2.99%), Mycetophyllia aliciae (2.03%), M. cavernosa (1.74%), and D. strigosa (1.45%). WPD-II was more common in the deeper strata (9-9.5 m), where 63% of the surveyed colonies were affected, although the disease was present along the entire reef. Presently, it is imperative to determine how fast the disease is spreading across the reef, how the disease spreads across the affected colonies and what the long-term effects on the reef will be.

Spatiotemporal patterns of coral disease prevalence on Heron Island, Great Barrier Reef, Australia

Science.gov (United States)

Haapkylä, J.; Melbourne-Thomas, J.; Flavell, M.; Willis, B. L.

2010-12-01

Despite increasing research effort on coral diseases, little is known about factors driving disease dynamics on the Great Barrier Reef (GBR). This is the first study to investigate the temporal patterns of coral disease prevalence and potential drivers of disease around Heron Island, in the southern Capricorn Bunker sector of the GBR. Surveys were conducted in two austral summers and three winters between November 2007 and August 2009 on six sites around the island. Six diseases were detected: brown band syndrome (BrB), growth anomalies (GA), ulcerative white spots (UWS), white syndrome (WS), skeletal eroding band disease (SEB) and black band disease (BBD). The lowest overall mean disease prevalence was 1.87 ± 0.75% (mean ± SE) in November 2007 and the highest 4.22 ± 1.72% in August 2008. There was evidence of seasonality for two diseases: BrB and UWS. This is the first study to report a higher prevalence of BrB in the winter. BrB had a prevalence of 3.29 ± 0.58% in August 2008 and 1.53 ± 0.28% in August 2009, while UWS was the most common syndrome in the summer with a prevalence of 1.12 ± 0.31% in November 2007 and 2.67 ± 0.52% prevalence in January 2008. The prevalence of GAs and SEB did not depend on the season, although the prevalence of GAs increased throughout the study period. WS had a slightly higher prevalence in the summer, but its overall prevalence was low (disease prevalence (12% of Acropora and 3.3% of Montipora species were diseased respectively). These results highlight the correlations between coral disease prevalence, seasonally varying environmental parameters and coral community composition. Given that diseases are likely to reduce the resilience of corals, seasonal patterns in disease prevalence deserve further research.

Metatranscriptome Sequencing of a Reef-building Coral Elucidates Holobiont Community Gene Functions in Health and Disease

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Timberlake, S.; Helbig, T.; Fernando, S.; Penn, K.; Alm, E.; Thompson, F.; Thompson, J. R.

2012-12-01

The coral reefs of the Abrolhos Bank of Brazil play a vital ecological role in the health of the Southern Atlantic Ocean, but accelerating rates of disease, particularly white plague, threaten this ecosystem. Thus, an understanding of white plague disease and diagnostic tests for it are urgently needed. The coral animal is associated with a distinct microbiome, a diverse assemblage of eukaryotes, bacteria, and viruses. That these microbes have a great influence on the health of the coral has been long known, however, most of their functions are still mysterious. While recent studies have contrasted healthy and white-plague-associated communities, the causative agents and mechanisms of the disease remain unknown. We collected fragments of healthy and diseased corals, as well as post-disease skeleton, from 12 colonies of the genus Mussismilia, the major component of the reef structure in the Abrolhos bank, and increasingly, a victim of white-plague disease. Fragments were flash-frozen in situ, and prepped for culture-free high throughput sequencing of gene transcripts with the Illumina II-G. While the membership of the microbial communities associated with coral has been previously described, the a coral holobiont community's gene function has, to date, never been assayed by this powerful approach. We designed a bioinformatics pipeline to analyze the short-read data from this complex sample: identifying the functions of genes expressed in the holobiont, and describing the active community's taxonomic composition. We show that gene functions expressed by the coral's bacterial assemblage are distinct from those of the underlying skeleton, and we highlight differences in the disease samples. We find that gene markers for the dissimilatory sulfate reduction pathway more abundant in the disease state, and we further quantify this difference with qPCR. Finally, we report the abundant expression of highly repetitive transcripts in the diseased coral samples, and highlight

Distribution and structure of the southernmost Caribbean coral reefs: golfo de Urabá, Colombia

Directory of Open Access Journals (Sweden)

J. M. Díaz

2000-09-01

Full Text Available The Gulf of Urabá represents the southernmost portion of the Caribbean Sea. Due to the large amounts of sediment and freshwater discharged by the Atrato river and several minor streams, water conditions in the area are far from being optimal for coral settlement and growth. However, fringing and patch reefs are developed along the rocky shores of the northwest margin of the Gulf. Based on field observations performed at 44 sites (12 of them assessed quantitatively, interpretation of air photography of the area and depth profiles, the distribution, structure and zonation of the reefs are described. Classification analysis of the 12 sample sites yielded four coral assemblages: Diploria strigosa, crustose algae, Siderastrea siderea, Agaricia spp., and mixed massive corals. Other two assemblages, dominated respectively by Millepora complanata and thickets of Acropora palmata were noticed during reconnaissance dives. The distribution of these zones within the reef seems likely to be mainly controlled by wave exposure, bottom topography, sedimentation, and light penetration. Reef development, coral diversity and live coral cover increase along the coast in a SE-NW direction, with an evident maximum near to the cove of Sapzurro, suggesting an overall improvement of conditions for coral growth and settlement in that direction. A total of 33 species of hard corals were recorded during the survey. It is apparent that the live coral cover, particularly of foliose and branching species, has notably declined recently.

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

KAUST Repository

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

2014-01-01

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

The relationship between gorgonian coral (Cnidaria: Gorgonacea) diseases and African dust storms

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Weir-Brush, J. R.; Garrison, V.H.; Smith, G.W.; Shinn, E.A.

2004-01-01

The number of reports of coral diseases has increased throughout the world in the last 20 years. Aspergillosis, which primarily affects Gorgonia ventalina and G. flabellum, is one of the few diseases to be characterized. This disease is caused by Aspergillus sydowii, a terrestrial fungus with a worldwide distribution. Upon infection, colonies may lose tissue, and ultimately, mortality may occur if the infection is not sequestered. The spores of A. sydowii are African dust storms transport and deposit pathogens, we collected air samples from both dust storms and periods of nondust in St. John, U.S. Virgin Islands. Because we focused on fungal pathogens and used A. sydowii as a model, we isolated and cultured fungi on various types of media. Fungi including Aspergillus spp. were isolated from air samples taken from dust events and non-dust events. Twenty-three separate cultures and seven genera were isolated from dust event samples whereas eight cultures from five genera were isolated from non-dust air samples. Three isolates from the Virgin Islands dust event samples morphologically identified as Aspergillus spp. produced signs of aspergillosis in seafans, and the original pathogens were re-isolated from those diseased seafans fulfilling Koch's Postulates. This research supports the hypothesis that African dust storms transport across the Atlantic Ocean and deposit potential coral pathogens in the Caribbean.

Distribution of Mysidium integrum (Tattersall) (Crustacea-mysidacea) in Venezuelan coral habitats

NARCIS (Netherlands)

Zoppi de Roa, Evelyn; Pedro Alonso, G.

1997-01-01

ZOPPI DE ROA, EVELYN & PEDRO ALONSO G.: Distribution of Mysidium integrum (Tattersall) (Crustacea: Mysidacea) in Venezuelan coral habitats. Studies Nat. Hist. Caribbean Region 73, Amsterdam 1997: 55-62. This paper reports the occurrence, distribution and some ecological aspects of mysids in six

Deep-sea scleractinian coral age and depth distributions in the northwest Atlantic for the last 225,000 years

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Robinson, L.F.; Adkins, J.F.; Scheirer, D.S.; Fernandez, D.P.; Gagnon, A.; Waller, R.G.

2007-01-01

Deep-sea corals have grown for over 200,000 yrs on the New England Seamounts in the northwest Atlantic, and this paper describes their distribution both with respect to depth and time. Many thousands of fossil scleractinian corals were collected on a series of cruises from 2003-2005; by contrast, live ones were scarce. On these seamounts, the depth distribution of fossil Desmophyllum dianthus (Esper, 1794) is markedly different to that of the colonial scleractinian corals, extending 750 m deeper in the water column to a distinct cut-off at 2500 m. This cut-off is likely to be controlled by the maximum depth of a notch-shaped feature in the seamount morphology. The ages of D. dianthus corals as determined by U-series measurements range from modern to older than 200,000 yrs. The age distribution is not constant over time, and most corals have ages from the last glacial period. Within the glacial period, increases in coral population density at Muir and Manning Seamounts coincided with times at which large-scale ocean circulation changes have been documented in the deep North Atlantic. Ocean circulation changes have an effect on coral distributions, but the cause of the link is not known. ?? 2007 Rosenstiel School of Marine and Atmospheric Science of the University of Miami.

Colony size-frequency distribution of pocilloporid juvenile corals along a natural environmental gradient in the Red Sea

KAUST Repository

Lozano-Cortes, Diego

2015-10-29

Coral colony size-frequency distributions can be used to assess population responses to local environmental conditions and disturbances. In this study, we surveyed juvenile pocilloporids, herbivorous fish densities, and algal cover in the central and southern Saudi Arabian Red Sea. We sampled nine reefs with different disturbance histories along a north–south natural gradient of physicochemical conditions (higher salinity and wider temperature fluctuations in the north, and higher turbidity and productivity in the south). Since coral populations with negatively skewed size-frequency distributions have been associated with unfavorable environmental conditions, we expected to find more negative distributions in the southern Red Sea, where corals are potentially experiencing suboptimal conditions. Although juvenile coral and parrotfish densities differed significantly between the two regions, mean colony size and size-frequency distributions did not. Results suggest that pocilloporid colony size-frequency distribution may not be an accurate indicator of differences in biological or oceanographic conditions in the Red Sea.

Colony size-frequency distribution of pocilloporid juvenile corals along a natural environmental gradient in the Red Sea.

Science.gov (United States)

Lozano-Cortés, Diego F; Berumen, Michael L

2016-04-30

Coral colony size-frequency distributions can be used to assess population responses to local environmental conditions and disturbances. In this study, we surveyed juvenile pocilloporids, herbivorous fish densities, and algal cover in the central and southern Saudi Arabian Red Sea. We sampled nine reefs with different disturbance histories along a north-south natural gradient of physicochemical conditions (higher salinity and wider temperature fluctuations in the north, and higher turbidity and productivity in the south). Since coral populations with negatively skewed size-frequency distributions have been associated with unfavorable environmental conditions, we expected to find more negative distributions in the southern Red Sea, where corals are potentially experiencing suboptimal conditions. Although juvenile coral and parrotfish densities differed significantly between the two regions, mean colony size and size-frequency distributions did not. Results suggest that pocilloporid colony size-frequency distribution may not be an accurate indicator of differences in biological or oceanographic conditions in the Red Sea. Copyright © 2015 Elsevier Ltd. All rights reserved.

AFSC/RACE/GAP/Rooper: Deep sea coral and sponge distribution

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National Oceanic and Atmospheric Administration, Department of Commerce — As part of a series of ongoing research projects, the AFSC has been mapping and modeling the distribution of deep-sea coral and sponge communities throughout Alaska....

Assessing the spatial distribution of coral bleaching using small unmanned aerial systems

Science.gov (United States)

Levy, Joshua; Hunter, Cynthia; Lukacazyk, Trent; Franklin, Erik C.

2018-06-01

Small unmanned aerial systems (sUAS) are an affordable, effective complement to existing coral reef monitoring and assessment tools. sUAS provide repeatable low-altitude, high-resolution photogrammetry to address fundamental questions of spatial ecology and community dynamics for shallow coral reef ecosystems. Here, we qualitatively describe the use of sUAS to survey the spatial characteristics of coral cover and the distribution of coral bleaching across patch reefs in Kānéohe Bay, Hawaii, and address limitations and anticipated technology advancements within the field of UAS. Overlapping sub-decimeter low-altitude aerial reef imagery collected during the 2015 coral bleaching event was used to construct high-resolution reef image mosaics of coral bleaching responses on four Kānéohe Bay patch reefs, totaling 60,000 m2. Using sUAS imagery, we determined that paled, bleached and healthy corals on all four reefs were spatially clustered. Comparative analyses of data from sUAS imagery and in situ diver surveys found as much as 14% difference in coral cover values between survey methods, depending on the size of the reef and area surveyed. When comparing the abundance of unhealthy coral (paled and bleached) between sUAS and in situ diver surveys, we found differences in cover from 1 to 49%, depending on the depth of in situ surveys, the percent of reef area covered with sUAS surveys and patchiness of the bleaching response. This study demonstrates the effective use of sUAS surveys for assessing the spatial dynamics of coral bleaching at colony-scale resolutions across entire patch reefs and evaluates the complementarity of data from both sUAS and in situ diver surveys to more accurately characterize the spatial ecology of coral communities on reef flats and slopes.

Virus-host interactions and their roles in coral reef health and disease.

Science.gov (United States)

Thurber, Rebecca Vega; Payet, Jérôme P; Thurber, Andrew R; Correa, Adrienne M S

2017-04-01

Coral reefs occur in nutrient-poor shallow waters, constitute biodiversity and productivity hotspots, and are threatened by anthropogenic disturbance. This Review provides an introduction to coral reef virology and emphasizes the links between viruses, coral mortality and reef ecosystem decline. We describe the distinctive benthic-associated and water-column- associated viromes that are unique to coral reefs, which have received less attention than viruses in open-ocean systems. We hypothesize that viruses of bacteria and eukaryotes dynamically interact with their hosts in the water column and with scleractinian (stony) corals to influence microbial community dynamics, coral bleaching and disease, and reef biogeochemical cycling. Last, we outline how marine viruses are an integral part of the reef system and suggest that the influence of viruses on reef function is an essential component of these globally important environments.

Cyanotoxins from black band disease of corals and from other coral reef environments.

Science.gov (United States)

Gantar, Miroslav; Sekar, Raju; Richardson, Laurie L

2009-11-01

Many cyanobacteria produce cyanotoxins, which has been well documented from freshwater environments but not investigated to the same extent in marine environments. Cyanobacteria are an obligate component of the polymicrobial disease of corals known as black band disease (BBD). Cyanotoxins were previously shown to be present in field samples of BBD and in a limited number of BBD cyanobacterial cultures. These toxins were suggested as one of the mechanisms contributing to BBD-associated coral tissue lysis and death. In this work, we tested nine cyanobacterial isolates from BBD and additionally nine isolated from non-BBD marine sources for their ability to produce toxins. The presence of toxins was determined using cell extracts of laboratory grown cyanobacterial cultures using ELISA and the PP2A assay. Based on these tests, it was shown that cyanobacterial toxins belonging to the microcystin/nodularin group were produced by cyanobacteria originating from both BBD and non-BBD sources. Several environmental factors that can be encountered in the highly dynamic microenvironment of BBD were tested for their effect on both cyanobacterial growth yield and rate of toxin production using two of the BBD isolates of the genera Leptolyngbya and Geitlerinema. While toxin production was the highest under mixotrophic conditions (light and glucose) for the Leptolyngbya isolate, it was highest under photoautotrophic conditions for the Geitlerinema isolate. Our results show that toxin production among marine cyanobacteria is more widespread than previously documented, and we present data showing three marine cyanobacterial genera (Phormidium, Pseudanabaena, and Spirulina) are newly identified as cyanotoxin producers. We also show that cyanotoxin production by BBD cyanobacteria can be affected by environmental factors that are present in the microenvironment associated with this coral disease.

Microbiome variation in corals with distinct depth distribution ranges across a shallow-mesophotic gradient (15-85 m)

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Glasl, Bettina; Bongaerts, Pim; Elisabeth, Nathalie H.; Hoegh-Guldberg, Ove; Herndl, Gerhard J.; Frade, Pedro R.

2017-06-01

Mesophotic coral ecosystems (MCEs) are generally poorly studied, and our knowledge of lower MCEs (below 60 m depth) is largely limited to visual surveys. Here, we provide a first detailed assessment of the prokaryotic community associated with scleractinian corals over a depth gradient to the lower mesophotic realm (15-85 m). Specimens of three Caribbean coral species exhibiting differences in their depth distribution ranges ( Agaricia grahamae, Madracis pharensis and Stephanocoenia intersepta) were collected with a manned submersible on the island of Curaçao, and their prokaryotic communities assessed using 16S rRNA gene sequencing analysis. Corals with narrower depth distribution ranges (depth-specialists) were associated with a stable prokaryotic community, whereas corals with a broader niche range (depth-generalists) revealed a higher variability in their prokaryotic community. The observed depth effects match previously described patterns in Symbiodinium depth zonation. This highlights the contribution of structured microbial communities over depth to the coral's ability to colonize a broader depth range.

Predation scars may influence host susceptibility to pathogens: evaluating the role of corallivores as vectors of coral disease.

Science.gov (United States)

Nicolet, K J; Chong-Seng, K M; Pratchett, M S; Willis, B L; Hoogenboom, M O

2018-03-27

Infectious diseases not regulated by host density, such as vector-borne diseases, have the potential to drive population declines and extinctions. Here we test the vector potential of the snail Drupella sp. and butterflyfish Chaetodon plebeius for two coral diseases, black band (BBD) and brown band (BrB) disease. Drupella transmitted BrB to healthy corals in 40% of cases immediately following feeding on infected corals, and even in 12% of cases 12 and 24 hours following feeding. However, Drupella was unable to transmit BBD in either transmission treatment. In a field experiment testing the vector potential of naturally-occurring fish assemblages, equivalent numbers of caged and uncaged coral fragments became infected with either BrB, BBD or skeletal eroding band, indicating that corallivorous fish were unlikely to have caused transmission. In aquaria, C. plebeius did not transmit either BBD or BrB, even following extended feeding on both infected and healthy nubbins. A literature review confirmed only four known coral disease vectors, all invertebrates, corroborating our conclusion that polyp-feeding fishes are unlikely to be vectors of coral diseases. This potentially because polyp-feeding fishes produce shallow lesions, not allowing pathogens to invade coral tissues. In contrast, corallivorous invertebrates that create deeper feeding scars increase pathogens transmission.

Experimental antibiotic treatment identifies potential pathogens of white band disease in the endangered Caribbean coral Acropora cervicornis.

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Sweet, M J; Croquer, A; Bythell, J C

2014-08-07

Coral diseases have been increasingly reported over the past few decades and are a major contributor to coral decline worldwide. The Caribbean, in particular, has been noted as a hotspot for coral disease, and the aptly named white syndromes have caused the decline of the dominant reef building corals throughout their range. White band disease (WBD) has been implicated in the dramatic loss of Acropora cervicornis and Acropora palmata since the 1970s, resulting in both species being listed as critically endangered on the International Union for Conservation of Nature Red list. The causal agent of WBD remains unknown, although recent studies based on challenge experiments with filtrate from infected hosts concluded that the disease is probably caused by bacteria. Here, we report an experiment using four different antibiotic treatments, targeting different members of the disease-associated microbial community. Two antibiotics, ampicillin and paromomycin, arrested the disease completely, and by comparing with community shifts brought about by treatments that did not arrest the disease, we have identified the likely candidate causal agent or agents of WBD. Our interpretation of the experimental treatments is that one or a combination of up to three specific bacterial types, detected consistently in diseased corals but not detectable in healthy corals, are likely causal agents of WBD. In addition, a histophagous ciliate (Philaster lucinda) identical to that found consistently in association with white syndrome in Indo-Pacific acroporas was also consistently detected in all WBD samples and absent in healthy coral. Treatment with metronidazole reduced it to below detection limits, but did not arrest the disease. However, the microscopic disease signs changed, suggesting a secondary role in disease causation for this ciliate. In future studies to identify a causal agent of WBD via tests of Henle-Koch's postulates, it will be vital to experimentally control for populations

Changes in Caribbean coral disease prevalence after the 2005 bleaching event.

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Cróquer, Aldo; Weil, Ernesto

2009-11-16

Bleaching events and disease epizootics have increased during the past decades, suggesting a positive link between these 2 causes in producing coral mortality. However, studies to test this hypothesis, integrating a broad range of hierarchical spatial scales from habitats to distant localities, have not been conducted in the Caribbean. In this study, we examined links between bleaching intensity and disease prevalence collected from 6 countries, 2 reef sites for each country, and 3 habitats within each reef site (N = 6 x 2 x 3 = 36 site-habitat combinations) during the peak of bleaching in 2005 and a year after, in 2006. Patterns of disease prevalence and bleaching were significantly correlated (Rho = 0.58, p = 0.04). Higher variability in disease prevalence after bleaching occurred among habitats at each particular reef site, with a significant increase in prevalence recorded in 4 of the 10 site-habitats where bleaching was intense and a non-significant increase in disease prevalence in 18 out of the 26 site-habitats where bleaching was low to moderate. A significant linear correlation was found (r = 0.89, p = 0.008) between bleaching and the prevalence of 2 virulent diseases (yellow band disease and white plague) affecting the Montastraea species complex. Results of this study suggest that if bleaching events become more intense and frequent, disease-related mortality of Caribbean coral reef builders could increase, with uncertain effects on coral reef resilience.

Disease outbreaks, bleaching and a cyclone drive changes in coral assemblages on an inshore reef of the Great Barrier Reef

Science.gov (United States)

Haapkylä, J.; Melbourne-Thomas, J.; Flavell, M.; Willis, B. L.

2013-09-01

Coral disease is a major threat to the resilience of coral reefs; thus, understanding linkages between disease outbreaks and disturbances predicted to increase with climate change is becoming increasingly important. Coral disease surveys conducted twice yearly between 2008 and 2011 at a turbid inshore reef in the central Great Barrier Reef spanned two disturbance events, a coral bleaching event in 2009 and a severe cyclone (cyclone `Yasi') in 2011. Surveys of coral cover, community structure and disease prevalence throughout this 4-yr study provide a unique opportunity to explore cumulative impacts of disturbance events and disease for inshore coral assemblages. The principal coral disease at the study site was atramentous necrosis (AtN), and it primarily affected the key inshore, reef-building coral Montipora aequituberculata. Other diseases detected were growth anomalies, white syndrome and brown band syndrome. Diseases affected eight coral genera, although Montipora was, by far, the genus mostly affected. The prevalence of AtN followed a clear seasonal pattern, with disease outbreaks occurring only in wet seasons. Mean prevalence of AtN on Montipora spp. (63.8 % ± 3.03) was three- to tenfold greater in the wet season of 2009, which coincided with the 2009 bleaching event, than in other years. Persistent wet season outbreaks of AtN combined with the impacts of bleaching and cyclone events resulted in a 50-80 % proportional decline in total coral cover. The greatest losses of branching and tabular acroporids occurred following the low-salinity-induced bleaching event of 2009, and the greatest losses of laminar montiporids occurred following AtN outbreaks in 2009 and in 2011 following cyclone Yasi. The shift to a less diverse coral assemblage and the concomitant loss of structural complexity are likely to have long-term consequences for associated vertebrate and invertebrate communities on Magnetic Island reefs.

The ecology of 'Acroporid white syndrome', a coral disease from the southern Great Barrier Reef.

Directory of Open Access Journals (Sweden)

George Roff

Full Text Available Outbreaks of coral disease have increased worldwide over the last few decades. Despite this, remarkably little is known about the ecology of disease in the Indo-Pacific Region. Here we report the spatiotemporal dynamics of a coral disease termed 'Acroporid white syndrome' observed to affect tabular corals of the genus Acropora on the southern Great Barrier Reef. The syndrome is characterised by rapid tissue loss initiating in the basal margins of colonies, and manifests as a distinct lesion boundary between apparently healthy tissue and exposed white skeleton. Surveys of eight sites around Heron Reef in 2004 revealed a mean prevalence of 8.1±0.9%, affecting the three common species (Acropora cytherea, A. hyacinthus, A. clathrata and nine other tabular Acropora spp. While all sizes of colonies were affected, white syndrome disproportionately affected larger colonies of tabular Acroporids (>80 cm. The prevalence of white syndrome was strongly related to the abundance of tabular Acroporids within transects, yet the incidence of the syndrome appears unaffected by proximity to other colonies, suggesting that while white syndrome is density dependant, it does not exhibit a strongly aggregated spatial pattern consistent with previous coral disease outbreaks. Acroporid white syndrome was not transmitted by either direct contact in the field or by mucus in aquaria experiments. Monitoring of affected colonies revealed highly variable rates of tissue loss ranging from 0 to 1146 cm(-2 week(-1, amongst the highest documented for a coral disease. Contrary to previous links between temperature and coral disease, rates of tissue loss in affected colonies increased threefold during the winter months. Given the lack of spatial pattern and non-infectious nature of Acroporid white syndrome, further studies are needed to determine causal factors and longer-term implications of disease outbreaks on the Great Barrier Reef.

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

Science.gov (United States)

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.

The presence of the cyanobacterial toxin microcystin in black band disease of corals.

Science.gov (United States)

Richardson, Laurie L; Sekar, Raju; Myers, Jamie L; Gantar, Miroslav; Voss, Joshua D; Kaczmarsky, Longin; Remily, Elizabeth R; Boyer, Gregory L; Zimba, Paul V

2007-07-01

Black band disease (BBD) is a migrating, cyanobacterial dominated, sulfide-rich microbial mat that moves across coral colonies lysing coral tissue. While it is known that BBD sulfate-reducing bacteria contribute to BBD pathogenicity by production of sulfide, additional mechanisms of toxicity may be involved. Using HPLC/MS, the cyanotoxin microcystin was detected in 22 field samples of BBD collected from five coral species on nine reefs of the wider Caribbean (Florida Keys and Bahamas). Two cyanobacterial cultures isolated from BBD, Geitlerinema and Leptolyngbya sp. contained microcystin based on HPLC/MS, with toxic activity confirmed using the protein phosphatase inhibition assay. The gene mcyA from the microcystin synthesis complex was detected in two field samples and from both BBD cyanobacterial cultures. Microcystin was not detected in six BBD samples from a different area of the Caribbean (St Croix, USVI) and the Philippines, suggesting regional specificity for BBD microcystin. This is the first report of the presence of microcystin in a coral disease.

Diversity and distribution of Actinobacteria associated with reef coral Porites lutea

Science.gov (United States)

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

Do elevated nutrients and organic carbon on Philippine reefs increase the prevalence of coral disease?

Science.gov (United States)

Kaczmarsky, L.; Richardson, L. L.

2011-03-01

Characterizations of Philippine coral diseases are very limited. The two most common, ulcerative white spot disease (UWS) and massive Porites growth anomalies (MPGA), target the genus Porites, a dominant reef-building genus. This is the first investigation in the Philippines to detect positive correlations between coral disease, nutrient levels, and organic carbon. A total of 5,843 Porites colonies were examined. Water and sediment samples were collected for analyses of nutrients (total nitrogen and phosphorus) and total organic carbon at 15 sites along a 40.5 km disease gradient, which was previously shown to positively correlate with human population levels. Results suggest that outbreaks of UWS and MPGAs are driven by elevated nutrient and organic carbon levels. Although the variables analyzed could be proxies for other causative agents (e.g., high sediment levels), the results provide quantitative evidence linking relatively higher coral disease prevalence to an anthropogenically impacted environment.

Bacterial profiling of White Plague Disease across corals and oceans indicates a conserved and distinct disease microbiome

KAUST Repository

Roder, C.; Arif, C.; Daniels, C.; Weil, E.; Voolstra, Christian R.

2014-01-01

microarrays to assay differences in bacterial assemblages of healthy and diseased colonies displaying White Plague Disease (WPD) signs from two closely related Caribbean coral species, Orbicella faveolata and Orbicella franksi. Analysis of differentially

Antibacterial Activity of Marine and Black Band Disease Cyanobacteria against Coral-Associated Bacteria

Science.gov (United States)

Gantar, Miroslav; Kaczmarsky, Longin T.; Stanić, Dina; Miller, Aaron W.; Richardson, Laurie L.

2011-01-01

Black band disease (BBD) of corals is a cyanobacteria-dominated polymicrobial disease that contains diverse populations of heterotrophic bacteria. It is one of the most destructive of coral diseases and is found globally on tropical and sub-tropical reefs. We assessed ten strains of BBD cyanobacteria, and ten strains of cyanobacteria isolated from other marine sources, for their antibacterial effect on growth of heterotrophic bacteria isolated from BBD, from the surface mucopolysaccharide layer (SML) of healthy corals, and three known bacterial coral pathogens. Assays were conducted using two methods: co-cultivation of cyanobacterial and bacterial isolates, and exposure of test bacteria to (hydrophilic and lipophilic) cyanobacterial cell extracts. During co-cultivation, 15 of the 20 cyanobacterial strains tested had antibacterial activity against at least one of the test bacterial strains. Inhibition was significantly higher for BBD cyanobacteria when compared to other marine cyanobacteria. Lipophilic extracts were more active than co-cultivation (extracts of 18 of the 20 strains were active) while hydrophilic extracts had very limited activity. In some cases co-cultivation resulted in stimulation of BBD and SML bacterial growth. Our results suggest that BBD cyanobacteria are involved in structuring the complex polymicrobial BBD microbial community by production of antimicrobial compounds. PMID:22073011

Disease prevalence and snail predation associated with swell-generated damage on the threatened coral, Acropora palmata (Lamarck

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Allan Joseph Bright

2016-05-01

Full Text Available Disturbances such as tropical storms cause coral mortality and reduce coral cover as a direct result of physical damage. Storms can be one of the most important disturbances in coral reef ecosystems, and it is crucial to understand their long-term impacts on coral populations. The primary objective of this study was to determine trends in disease prevalence and snail predation on damaged and undamaged colonies of the threatened coral species, Acropora palmata, following an episode of heavy ocean swells in the US Virgin Islands (USVI. At three sites on St. Thomas and St. John, colonies of A. palmata were surveyed monthly over one year following a series of large swells in March 2008 that fragmented 30 to 93% of colonies on monitored reefs. Post-disturbance surveys conducted from April 2008 through March 2009 showed that swell-generated damage to A. palmata caused negative indirect effects that compounded the initial direct effects of physical disturbance. During the 12 months after the swell event, white pox disease prevalence was 41% higher for colonies that sustained damage from the swells than for undamaged colonies (df = 207, p = 0.01 with greatest differences in disease prevalence occurring during warm water months. In addition, the corallivorous snail, Coralliophila abbreviata, was 46% more abundant on damaged corals than undamaged corals during the 12 months after the swell event (df = 207, p = 0.006.

Disease prevalence and snail predation associated with swell-generated damage on the threatened coral, Acropora palmata (Lamarck)

Science.gov (United States)

Bright, Allan J.; Rogers, Caroline S.; Brandt, Marilyn E.; Muller, Erinn; Smith, Tyler B.

2016-01-01

Disturbances such as tropical storms cause coral mortality and reduce coral cover as a direct result of physical damage. Storms can be one of the most important disturbances in coral reef ecosystems, and it is crucial to understand their long-term impacts on coral populations. The primary objective of this study was to determine trends in disease prevalence and snail predation on damaged and undamaged colonies of the threatened coral species, Acropora palmata, following an episode of heavy ocean swells in the US Virgin Islands (USVI). At three sites on St. Thomas and St. John, colonies of A. palmata were surveyed monthly over 1 year following a series of large swells in March 2008 that fragmented 30–93% of colonies on monitored reefs. Post-disturbance surveys conducted from April 2008 through March 2009 showed that swell-generated damage to A. palmata caused negative indirect effects that compounded the initial direct effects of physical disturbance. During the 12 months after the swell event, white pox disease prevalence was 41% higher for colonies that sustained damage from the swells than for undamaged colonies (df = 207, p = 0.01) with greatest differences in disease prevalence occurring during warm water months. In addition, the corallivorous snail, Coralliophila abbreviata, was 46% more abundant on damaged corals than undamaged corals during the 12 months after the swell event (df = 207, p = 0.006).

Natural Product Chemistry of Gorgonian Corals of the Family Plexauridae Distributed in the Indo-Pacific Ocean

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Ping-Jyun Sung

2012-11-01

Full Text Available The structures, names, bioactivities and references of 105 natural products obtained from gorgonian corals belonging to the family Plexauridae with an Indo-Pacific distribution are described in this review. All compounds mentioned in this review were obtained from gorgonian corals belonging to the genera Astrogorgia, Bebryce, Echinomuricea, Euplexaura and Menella.

Coral transcriptome and bacterial community profiles reveal distinct Yellow Band Disease states in Orbicella faveolata

KAUST Repository

Closek, Collin J.

2014-06-20

Coral diseases impact reefs globally. Although we continue to describe diseases, little is known about the etiology or progression of even the most common cases. To examine a spectrum of coral health and determine factors of disease progression we examined Orbicella faveolata exhibiting signs of Yellow Band Disease (YBD), a widespread condition in the Caribbean. We used a novel combined approach to assess three members of the coral holobiont: the coral-host, associated Symbiodinium algae, and bacteria. We profiled three conditions: (1) healthy-appearing colonies (HH), (2) healthy-appearing tissue on diseased colonies (HD), and (3) diseased lesion (DD). Restriction fragment length polymorphism analysis revealed health state-specific diversity in Symbiodinium clade associations. 16S ribosomal RNA gene microarrays (PhyloChips) and O. faveolata complimentary DNA microarrays revealed the bacterial community structure and host transcriptional response, respectively. A distinct bacterial community structure marked each health state. Diseased samples were associated with two to three times more bacterial diversity. HD samples had the highest bacterial richness, which included components associated with HH and DD, as well as additional unique families. The host transcriptome under YBD revealed a reduced cellular expression of defense- and metabolism-related processes, while the neighboring HD condition exhibited an intermediate expression profile. Although HD tissue appeared visibly healthy, the microbial communities and gene expression profiles were distinct. HD should be regarded as an additional (intermediate) state of disease, which is important for understanding the progression of YBD. © 2014 International Society for Microbial Ecology. All rights reserved.

Temporal and spatial distributions of cold-water corals in the Drake Passage: insights from the last 35,000 years

Science.gov (United States)

Margolin, Andrew R.; Robinson, Laura F.; Burke, Andrea; Waller, Rhian G.; Scanlon, Kathryn M.; Roberts, Mark L.; Auro, Maureen E.; van de Flierdt, Tina

2014-01-01

Scleractinian corals have a global distribution ranging from shallow tropical seas to the depths of the Southern Ocean. Although this distribution is indicative of the corals having a tolerance to a wide spectrum of environmental conditions, individual species seem to be restricted to a much narrower range of ecosystem variables. One way to ascertain the tolerances of corals, with particular focus on the potential impacts of changing climate, is to reconstruct their growth history across a range of environmental regimes. This study examines the spatial and temporal distribution of the solitary scleractinian corals Desmophyllum dianthus, Gardineria antarctica, Balanophyllia malouinensis, Caryophyllia spp. and Flabellum spp. from five sites in the Drake Passage which cross the major frontal zones. A rapid reconnaissance radiocarbon method was used to date more than 850 individual corals. Coupled with U-Th dating, an age range of present day back to more than 100 thousand years was established for corals in the region. Within this age range there are distinct changes in the temporal and spatial distributions of these corals, both with depth and latitude, and on millennial timescales. Two major patterns that emerge are: (1) D. dianthus populations show clear variability in their occurrence through time depending on the latitudinal position within the Drake Passage. North of the Subantarctic Front, D. dianthus first appears in the late deglaciation (~17,000 years ago) and persists to today. South of the Polar Front, in contrast, early deglacial periods, with a few modern occurrences. A seamount site between the two fronts exhibits characteristics similar to both the northern and southern sites. This shift across the frontal zones within one species cannot yet be fully explained, but it is likely to be linked to changes in surface productivity, subsurface oxygen concentrations, and carbonate saturation state. (2) at locations where multiple genera were dated, differences

Spectral response of the coral rubble, living corals, and dead corals: study case on the Spermonde Archipelago, Indonesia

Science.gov (United States)

Nurdin, Nurjannah; Komatsu, Teruhisa; Yamano, Hiroya; Arafat, Gulam; Rani, Chair; Akbar AS, M.

2012-10-01

Coral reefs play important ecological services such as providing foods, biodiversity, nutrient recycling etc. for human society. On the other hand, they are threatened by human impacts such as illegal fishing and environmental changes such as rises of sea water temperature and sea level due to global warming. Thus, it is very important to monitor dynamic spatial distributions of coral reefs and related habitats such as coral rubble, dead coral, bleached corals, seagrass, etc. Hyperspectral data, in particular, offer high potential for characterizing and mapping coral reefs because of their capability to identify individual reef components based on their detailed spectral response. We studied the optical properties by measuring in situ spectra of living corals, dead coral and coral rubble covered with algae. Study site was selected in Spermonde archipelago, South Sulawesi, Indonesia because this area is included in the highest diversity of corals in the world named as Coral Triangle, which is recognized as the global centre of marine biodiversity and a global priority for conservation. Correlation analysis and cluster analysis support that there are distinct differences in reflectance spectra among categories. Common spectral characteristic of living corals, dead corals and coral rubble covered with algae was a reflectance minimum at 674 nm. Healthy corals, dead coral covered with algae and coral rubble covered with algae showed high similarity of spectral reflectance. It is estimated that this is due to photsynthetic pigments.

SPATIAL HETEROGENEITY OF PHOTOSYNTHETIC ACTIVITY WITHIN DISEASED CORALS FROM THE GREAT BARRIER REEF

DEFF Research Database (Denmark)

Roff, George; Ulstrup, Karin Elizabeth; Fine, Maoz

2008-01-01

Morphological diagnosis and descriptions of seven disease-like syndromes affecting scleractinian corals were characterized from the southern Great Barrier Reef (GBR). Chl a fluorescence of PSII was measured using an Imaging-PAM (pulse amplitude modulated) fluorometer, enabling visualization...... with white patch syndrome appeared to impact primarily on the symbiotic dinoflagellates, as evidenced by declines in minimum fluorescence (F0) and maximum quantum yield (Fv/Fm), with no indication of degeneration in the host tissues. Our results suggest that for the majority of coral syndromes from the GBR......, pathogenesis occurs in the host tissue, while the impact on the zooxanthellae populations residing in affected corals is minimal....

Algae as reservoirs for coral pathogens.

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Michael J Sweet

Full Text Available Benthic algae are associated with coral death in the form of stress and disease. It's been proposed that they release exudates, which facilitate invasion of potentially pathogenic microbes at the coral-algal interface, resulting in coral disease. However, the original source of these pathogens remains unknown. This study examined the ability of benthic algae to act as reservoirs of coral pathogens by characterizing surface associated microbes associated with major Caribbean and Indo-Pacific algal species/types and by comparing them to potential pathogens of two dominant coral diseases: White Syndrome (WS in the Indo-Pacific and Yellow Band Disease (YBD in the Caribbean. Coral and algal sampling was conducted simultaneously at the same sites to avoid spatial effects. Potential pathogens were defined as those absent or rare in healthy corals, increasing in abundance in healthy tissues adjacent to a disease lesion, and dominant in disease lesions. Potentially pathogenic bacteria were detected in both WS and YBD and were also present within the majority of algal species/types (54 and 100% for WS and YBD respectively. Pathogenic ciliates were associated only with WS and not YBD lesions and these were also present in 36% of the Indo-Pacific algal species. Although potential pathogens were associated with many algal species, their presence was inconsistent among replicate algal samples and detection rates were relatively low, suggestive of low density and occurrence. At the community level, coral-associated microbes irrespective of the health of their host differed from algal-associated microbes, supporting that algae and corals have distinctive microbial communities associated with their tissue. We conclude that benthic algae are common reservoirs for a variety of different potential coral pathogens. However, algal-associated microbes alone are unlikely to cause coral death. Initial damage or stress to the coral via other competitive mechanisms is

Fungi and their role in corals and coral reef ecosystems

Digital Repository Service at National Institute of Oceanography (India)

Raghukumar, C.; Ravindran, J.

fungal hyphae have on corals, their mechanism of penetration and the role their enzymes play in this process. 3.2. Fungi as pathogens in reef ecosystems Besides natural disasters and climate warming, diseases have contributed to coral decline... defence mechanisms against predation, biofouling, diseases, environmental perturbations and other stressors. These chemicals are either synthesized by the organisms themselves or their endobiontic microorganisms. If these valuable compounds...

Abundance and Multilocus Sequence Analysis of Vibrio Bacteria Associated with Diseased Elkhorn Coral (Acropora palmata) of the Florida Keys.

Science.gov (United States)

Kemp, Keri M; Westrich, Jason R; Alabady, Magdy S; Edwards, Martinique L; Lipp, Erin K

2018-01-15

The critically endangered elkhorn coral ( Acropora palmata ) is affected by white pox disease (WPX) throughout the Florida Reef Tract and wider Caribbean. The bacterium Serratia marcescens was previously identified as one etiologic agent of WPX but is no longer consistently detected in contemporary outbreaks. It is now believed that multiple etiologic agents cause WPX; however, to date, no other potential pathogens have been thoroughly investigated. This study examined the association of Vibrio bacteria with WPX occurrence from August 2012 to 2014 at Looe Key Reef in the Florida Keys, USA. The concentration of cultivable Vibrio was consistently greater in WPX samples than in healthy samples. The abundance of Vibrio bacteria relative to total bacteria was four times higher in samples from WPX lesions than in adjacent apparently healthy regions of diseased corals based on quantitative PCR (qPCR). Multilocus sequence analysis (MLSA) was used to assess the diversity of 69 Vibrio isolates collected from diseased and apparently healthy A. palmata colonies and the surrounding seawater. Vibrio species with known pathogenicity to corals were detected in both apparently healthy and diseased samples. While the causative agent(s) of contemporary WPX outbreaks remains elusive, our results suggest that Vibrio spp. may be part of a nonspecific heterotrophic bacterial bloom rather than acting as primary pathogens. This study highlights the need for highly resolved temporal sampling in situ to further elucidate the role of Vibrio during WPX onset and progression. IMPORTANCE Coral diseases are increasing worldwide and are now considered a major contributor to coral reef decline. In particular, the Caribbean has been noted as a coral disease hot spot, owing to the dramatic loss of framework-building acroporid corals due to tissue loss diseases. The pathogenesis of contemporary white pox disease (WPX) outbreaks in Acropora palmata remains poorly understood. This study investigates the

Fitness consequences of habitat variability, trophic position, and energy allocation across the depth distribution of a coral-reef fish

Science.gov (United States)

Goldstein, E. D.; D'Alessandro, E. K.; Sponaugle, S.

2017-09-01

Environmental clines such as latitude and depth that limit species' distributions may be associated with gradients in habitat suitability that can affect the fitness of an organism. With the global loss of shallow-water photosynthetic coral reefs, mesophotic coral ecosystems ( 30-150 m) may be buffered from some environmental stressors, thereby serving as refuges for a range of organisms including mobile obligate reef dwellers. Yet habitat suitability may be diminished at the depth boundary of photosynthetic coral reefs. We assessed the suitability of coral-reef habitats across the majority of the depth distribution of a common demersal reef fish ( Stegastes partitus) ranging from shallow shelf (SS, restrict foraging. Fish in MP environments had a broader diet niche, higher trophic position, and higher muscle C:N ratios compared to shallower environments. High C:N ratios suggest increased tissue lipid content in fish in MP habitats that coincided with higher investment in reproduction based on gonado-somatic index. These results suggest that peripheral MP reefs are suitable habitats for demersal reef fish and may be important refuges for organisms common on declining shallow coral reefs.

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

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Alejandra Verde

2016-07-01

Full Text Available 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.

Occurrence and distribution of soft corals (Octocorallia: Alcyonacea) from the Andaman and Nicobar Islands

Digital Repository Service at National Institute of Oceanography (India)

Jayasree, V.; Bhat, K.L.; Parulekar, A.H.

with resistance to harsh environments and life history parameters. Competitive interaction with other benthic reef-organisms also plays a major role in the distribution of soft corals in the Andaman and Nicobar Islands....

Host tolerance, not symbiont tolerance, determines the distribution of coral species in relation to their environment at a Central Pacific atoll

Science.gov (United States)

Wicks, L. C.; Gardner, J. P. A.; Davy, S. K.

2012-06-01

Tolerance of environmental variables differs between corals and their dinoflagellate symbionts ( Symbiodinium spp.), controlling the holobiont's (host and symbiont combined) resilience to environmental stress. However, the ecological role that environmental variables play in holobiont distribution remains poorly understood. We compared the drivers of symbiont and coral species distributions at Palmyra Atoll, a location with a range of reef environments from low to high sediment concentrations (1-52 g dry weight m-2 day-1). We observed uniform holobiont partnerships across the atoll (e.g. Montipora spp. with Symbiodinium type C15 at all sites). Multivariate analysis revealed that field-based estimates of settling sediment predominantly explained the spatial variation of coral species among sites ( P coral rather than Symbiodinium physiology. The data highlight the importance of host tolerance to environmental stressors, which should be considered simultaneously with symbiont sensitivity when considering the impact of variations in environmental conditions on coral communities.

Trade-offs in disease and bleaching susceptibility among two color morphs of the Hawaiian reef coral, Montipora capitata

Science.gov (United States)

Shore-Maggio, Amanda; Callahan, Sean M.; Aeby, Greta S.

2018-06-01

Two threats impacting coral reefs are bleaching and disease, and differential susceptibility to both exists among and within coral taxa. Bleaching resistance is commonly linked to the clade of endosymbiotic Symbiodinium, but may come at a cost to other biological traits. Montipora capitata is an Indo-Pacific reef-building coral with two color morphs, red and orange, which harbor different clades of Symbiodinium. We explored whether these color morphs displayed differences in bleaching/disease susceptibility and other biological traits (growth rate, reproductive output, and lipid content). We found a trade-off between disease and bleaching susceptibility. The orange morph had significantly higher disease prevalence, whereas the red morph had significantly higher bleaching prevalence. Thermal stress experiments found that bleaching and loss of photochemical efficiency occurred significantly faster in the red morph, but at normal temperatures, the red morph had a significantly higher growth rate. Higher abundance of the red morph in the field suggests that disease resistance is a more successful strategy in the absence of thermal stress events. The orange morph may better tolerate increases in sea temperatures, but may not persist due to decreased growth rate and increased disease susceptibility. Trade-offs in response to stressors highlight the need to consider local and global threats to coral reefs.

Predicting drivers and distributions of deep-sea ecosystems: A cold-water coral case study

DEFF Research Database (Denmark)

Mohn, Christian; Rengstorf, Anna; Brown, Colin

2015-01-01

pertusa as a case study (Rengstorf et al., 2014). The study shows that predictive models incorporating hydrodynamic variables perform significantly better than models based on terrain parameters only. They are a potentially powerful tool to improve our understanding of deep-sea ecosystem functioning......, facilitating species distribution modelling with high spatial detail. In this study, we used high resolution data (250 m grid size) from a newly developed hydrodynamic model to explore linkages between key physical drivers and occurrences of the cold-water coral Lophelia pertusa in selected areas of the NE...... and to provide decision support for marine spatial planning and conservation in the deep sea. Mohn et al., 2014.Linking benthic hydrodynamics and cold water coral occurrences: A high-resolution model study at three cold-water coral provinces in the NE Atlantic. Progress in Oceanography 122, 92-104. Rengstorf et...

Distribution, behavior, and condition of herbivorous fishes on coral reefs track algal resources.

Science.gov (United States)

Tootell, Jesse S; Steele, Mark A

2016-05-01

Herbivore distribution can impact community structure and ecosystem function. On coral reefs, herbivores are thought to play an important role in promoting coral dominance, but how they are distributed relative to algae is not well known. Here, we evaluated whether the distribution, behavior, and condition of herbivorous fishes correlated with algal resource availability at six sites in the back reef environment of Moorea, French Polynesia. Specifically, we tested the hypotheses that increased algal turf availability would coincide with (1) increased biomass, (2) altered foraging behavior, and (3) increased energy reserves of herbivorous fishes. Fish biomass and algal cover were visually estimated along underwater transects; behavior of herbivorous fishes was quantified by observations of focal individuals; fish were collected to assess their condition; and algal turf production rates were measured on standardized tiles. The best predictor of herbivorous fish biomass was algal turf production, with fish biomass increasing with algal production. Biomass of herbivorous fishes was also negatively related to sea urchin density, suggesting competition for limited resources. Regression models including both algal turf production and urchin density explained 94 % of the variation in herbivorous fish biomass among sites spread over ~20 km. Behavioral observations of the parrotfish Chlorurus sordidus revealed that foraging area increased as algal turf cover decreased. Additionally, energy reserves increased with algal turf production, but declined with herbivorous fish density, implying that algal turf is a limited resource for this species. Our findings support the hypothesis that herbivorous fishes can spatially track algal resources on coral reefs.

Effects of herbicides on coral and seasonal distribution in water and sediments collected from rivers and coral reefs of the Ryukyu Archipelago, Japan

Science.gov (United States)

Kaneshiro, A.; Fujimura, H.; Oomori, T.; Gima, S.; Suzuki, Y.; Casareto, B. E.; Higuchi, T.; Sagawa, T.

2011-12-01

Introduction Coral reefs are subjected to artificial chemicals such as herbicide and pesticides. Diuron [N'-(3, 4-dichlorophenyl)-N, N-dimethylurea] is one of the active constituent contained in a herbicide. Although acute effects of diuron on coral are reported by several researchers, longer-period toxicity with lower level concentration and synergistic effect between the herbicide and soil sedimentation from river water have not been studied. We investigated the concentration level, distribution, seasonal variation and accumulation of several herbicides and pesticides in coral reef and river in Ishigaki Island and Okinawa Island, and estimated the rates of carbon production of calcification and photosynthesis to access the effects of herbicides on coral. Materials and Methods Water and sediment samples were collected from Todoroki river and Shiraho coral reef in Ishigaki Island and several rivers from Okinawa Island in August 2010 to August 2011. Diuron and other active constituents were extracted using a solid-phase column and measured with a liquid chromatography-tandem mass spectrometry (LC-MS/MS). Corals for the experiment were collected from Okinawa Island and incubated in glass bottles. Seawater adjusted several concentrations of herbicide was continuously supplied to the bottles. Coral calcification and photosynthesis were estimated based on the change in total alkalinity and pH during a few hours when we temporary cease the water flow. Results and Discussion Higher diuron of 563 ng/L in water and 26 μg/kg in sediment was detected at the headwater of the Todoroki river in Ishigaki. in June. Sugarcane plantation is prevailing in Todoroki river area and rainwater can tend to gather topographically to upstream of the river. The higher concentration at the headwater decreased to 23 ng/L toward the river mouth. On the whole, the concentrations were higher during summer and lower in the other seasons in Ishigaki. On the other hand, seasonal variation was not

INVENTORY AND DISTRIBUTION OF MOLLUSC IN CORAL REEF OF BACAN ISLAND WATERS, NORTH MALUKU PROVINCE

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Hendrik A.W. Cappenberg

2017-11-01

Full Text Available Bacan Island waters of North Maluku Province consisted of three main tropical ecosystems, namely mangrove, seagrass, and coral reef with the highest marine biodiversity. Mollusc is a group of marine fauna that most of them associated with coral reef.  However, little is known about their information in the Bacan Island due to lack of study conducted there. The purpose of this study is to observe the diversity and distribution of mollusc fauna in the coral reef flat of Bacan Island. Mollusc inventory was done using Rapid Reef Resource Assessment (RRA method by snorkling in the reefs of east coast (25 sites and west coast (10 sites of Bacan Island. The molluscs found were directly identified into species level and recorded.  Results of inventory show that there are 47 species belong to 19 families with the family of Muricidae is the highest diversity (6 species, while the lowest are Buccinidae, Bursidae, Haliotidae, Olividae, Cardiidae, Isognomonidae and Spondylidae, respectively with only 1 species in each of those families. The highest species number of mollusc was distributed along the east coast of the island (40 species, and the lowest one was in the west coast (37 species. Some species such as Tridacna spp., Pinctada margaritifera and Pteria penguin are important species, because they have economical values. Keywords:       biodiversity, molluscs, coral reef, Bacan Island, North Maluku

Distribution and covering percentage of sponge (Porifera in different coral reef condition and depth in Barranglompo Island, South Sulawesi

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SUHARYANTO

2008-07-01

Full Text Available In 1996, four specieses of sponge namely Auletta sp., Callyspongia pseudoreticulata, Callyspongia sp., and Halichondria sp. have been potentially identified as bacteriside for fishery commodities. Nevertheless, information on sponge distribution, its covering percentage, and its habitate are still very little. Observation on distribution and abundance of sponge was conducted in the Southeastern and the Northwestern part of Barranglompo Island, South Sulawesi, using scuba diving set and under water writting tools. At first, coral reef condition in 3 and 10 m depths up to 100 m length of shore line were observed in both stations, using “lifeform method”. Then distribution and covering percentage of sponge, biotic and abiotic factor in 3, 6, 9, and 12 m depths in both stations were examined using “square transect method”. The result showed that different coral reef condition qualitatively causes different of sponge species distribution, but quantitatively not significantly different (P>0,05 on its covering percentage. It was also found that generally sponge grows better at the dead coral where no other biotic organism around.

Utilization of mucus from the coral Acropora palmata by the pathogen Serratia marcescens and by environmental and coral commensal bacteria.

Science.gov (United States)

Krediet, Cory J; Ritchie, Kim B; Cohen, Matthew; Lipp, Erin K; Sutherland, Kathryn Patterson; Teplitski, Max

2009-06-01

In recent years, diseases of corals caused by opportunistic pathogens have become widespread. How opportunistic pathogens establish on coral surfaces, interact with native microbiota, and cause disease is not yet clear. This study compared the utilization of coral mucus by coral-associated commensal bacteria ("Photobacterium mandapamensis" and Halomonas meridiana) and by opportunistic Serratia marcescens pathogens. S. marcescens PDL100 (a pathogen associated with white pox disease of Acroporid corals) grew to higher population densities on components of mucus from the host coral. In an in vitro coculture on mucus from Acropora palmata, S. marcescens PDL100 isolates outgrew coral isolates. The white pox pathogen did not differ from other bacteria in growth on mucus from a nonhost coral, Montastraea faveolata. The ability of S. marcescens to cause disease in acroporid corals may be due, at least in part, to the ability of strain PDL100 to build to higher population numbers within the mucus surface layer of its acroporid host. During growth on mucus from A. palmata, similar glycosidase activities were present in coral commensal bacteria, in S. marcescens PDL100, and in environmental and human isolates of S. marcescens. The temporal regulation of these activities during growth on mucus, however, was distinct in the isolates. During early stages of growth on mucus, enzymatic activities in S. marcescens PDL100 were most similar to those in coral commensals. After overnight incubation on mucus, enzymatic activities in a white pox pathogen were most similar to those in pathogenic Serratia strains isolated from human mucosal surfaces.

Pyrosequencing of the bacteria associated with Platygyra carnosus corals with skeletal growth anomalies reveals differences in bacterial community composition in apparently healthy and diseased tissues

Directory of Open Access Journals (Sweden)

Jenny Chun-Yee Ng

2015-10-01

Full Text Available Corals are rapidly declining globally due to coral diseases. Skeletal growth anomalies (SGA or coral tumors are a group of coral diseases that affect coral reefs worldwide, including Hong Kong waters in the Indo-Pacific region. To better understand how bacterial communities may vary in corals with SGA, for the first time, we examined the bacterial composition associated with the apparently healthy and the diseased tissues of SGA-affected Platgyra carnosus using 16S ribosomal rRNA gene pyrosequencing. Taxonomic analysis revealed Proteobacteria, Bacteroidetes, Cyanobacteria, and Actinobacteria as the main phyla in both the apparently healthy and the diseased tissues. A significant difference in the bacterial community composition was observed between the two conditions at the OTU level. Diseased tissues were associated with higher abundances of Acidobacteria and Gemmatimonadetes, and a lower abundance of Spirochaetes. Several OTUs belonging to Rhodobacteraceae, Rhizobiales, Gammaproteobacteria, and Cytophaga-Flavobacterium-Bacteroidetes (CFB were strongly associated with the diseased tissues. These groups of bacteria may contain potential pathogens involved with the development of SGA or opportunistic secondary or tertiary colonizers that proliferated upon the health-compromised coral host. We suggest that these bacterial groups to be further studied based on inoculation experiments and testing of Koch’s postulates in efforts to understand the etiology and progression of SGA.

Linking Wave Forcing to Coral Cover and Structural Complexity Across Coral Reef Flats

Science.gov (United States)

Harris, D. L.; Rovere, A.; Parravicini, V.; Casella, E.

2015-12-01

The hydrodynamic regime is a significant component in the geomorphic and ecological development of coral reefs. The energy gradients and flow conditions generated by the breaking and transformation of waves across coral reef crests and flats drive changes in geomorphic structure, and coral growth form and distribution. One of the key aspects in regulating the wave energy propagating across reef flats is the rugosity or roughness of the benthic substrate. Rugosity and structural complexity of coral reefs is also a key indicator of species diversity, ecological functioning, and reef health. However, the links between reef rugosity, coral species distribution and abundance, and hydrodynamic forcing are poorly understood. In this study we examine this relationship by using high resolution measurement of waves in the surf zone and coral reef benthic structure.Pressure transducers (logging at 4 Hz) were deployed in cross reef transects at two sites (Tiahura and Ha'apiti reef systems) in Moorea, French Polynesia with wave characteristics determined on a wave by wave basis. A one dimensional hydrodynamic model (XBeach) was calibrated from this data to determine wave processes on the reef flats under average conditions. Transects of the reef benthic structure were conducted using photographic analysis and the three dimensional reef surface was constructed using structure from motion procedures. From this analysis reef rugosity, changes in coral genus and growth form, and across reef shifts in benthic community were determined. The results show clear changes in benthic assemblages along wave energy gradients with some indication of threshold values of wave induced bed shear stress above which live coral cover was reduced. Reef rugosity was shown to be significantly along the cross-reef transect which has important implications for accurate assessment of wave dissipation across coral reef flats. Links between reef rugosity and coral genus were also observed and may indicate

Bacterial community structure associated with white band disease in the elkhorn coral Acropora palmata determined using culture-independent 16S rRNA techniques.

Science.gov (United States)

Pantos, Olga; Bythell, John C

2006-03-23

Culture-independent molecular (16S ribosomal RNA) techniques showed distinct differences in bacterial communities associated with white band disease (WBD) Type I and healthy elkhorn coral Acropora palmata. Differences were apparent at all levels, with a greater diversity present in tissues of diseased colonies. The bacterial community associated with remote, non-diseased coral was distinct from the apparently healthy tissues of infected corals several cm from the disease lesion. This demonstrates a whole-organism effect from what appears to be a localised disease lesion, an effect that has also been recently demonstrated in white plague-like disease in star coral Montastraea annularis. The pattern of bacterial community structure changes was similar to that recently demonstrated for white plague-like disease and black band disease. Some of the changes are likely to be explained by the colonisation of dead and degrading tissues by a micro-heterotroph community adapted to the decomposition of coral tissues. However, specific ribosomal types that are absent from healthy tissues appear consistently in all samples of each of the diseases. These ribotypes are closely related members of a group of alpha-proteobacteria that cause disease, notably juvenile oyster disease, in other marine organisms. It is clearly important that members of this group are isolated for challenge experiments to determine their role in the diseases.

CRED REA Coral Health and Disease Assessment at Guam, Marianas Archipelago in 2007

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 10 sites at...

Environmental distribution of coral-associated relatives of apicomplexan parasites

Czech Academy of Sciences Publication Activity Database

Janouškovec, J.; Horák, Aleš; Barott, K. L.; Rohwer, F. L.; Keeling, P. J.

2013-01-01

Roč. 7, č. 2 (2013), s. 444-447 ISSN 1751-7362 Institutional support: RVO:60077344 Keywords : apicomplexan-related lineages * Chromera * coral symbionts * coral reef ecosystem Subject RIV: EH - Ecology, Behaviour Impact factor: 9.267, year: 2013

A New Perspective: Assessing the Spatial Distribution of Coral Bleaching with Unmanned Low Altitude Remote Sensing Systems

Science.gov (United States)

Levy, J.; Franklin, E. C.; Hunter, C. L.

2016-12-01

Coral reefs are biodiversity hotspots that are vital to the function of global economic and biological processes. Coral bleaching is a significant contributor to the global decline of reefs and can impact an expansive reef area over short timescales. In order to understand the dynamics of coral bleaching and how these stress events impact reef ecosystems, it is important to conduct rapid bleaching surveys at functionally important spatial scales. Due to the inherent heterogeneity, size, and in some cases, remoteness of coral reefs, it is difficult to routinely monitor coral bleaching dynamics before, during, and after bleaching. Additionally, current in situ survey methods only collect snippets of discrete reef data over small reef areas, which are unable to accurately represent the reef as a whole. We present a new technique using small unmanned aerial systems (sUAS) as cost effective, efficient monitoring tools that target small to intermediate-scale reef dynamics to understand the spatial distribution of bleached coral colonies during the 2015 bleaching event on patch reefs in Kaneohe Bay, Oahu. Overlapping low altitude aerial images were collected at four reefs during the bleaching period and processed using Structure-from-Motion techniques to produce georeferenced and spatially accurate orthomosaics of complete reef areas. Mosaics were analyzed using manual and heuristic neural network classification schemes to identify comprehensive populations of bleached and live coral on each patch reef. We found that bleached colonies had random and clumped distributions on patch reefs in Kaneohe Bay depending on local environmental conditions. Our work demonstrates that sUAS provide a low cost, efficient platform that can rapidly and repeatedly collect high-resolution imagery (1 cm/pixel) and map large areas of shallow reef ecosystems (5 hectares). This study proves the feasibility of utilizing sUAS as a tool to collect spatially rich reef data that will provide reef

Spatial distribution and abundance of nonindigenous coral genus Tubastraea (Cnidaria, Scleractinia around Ilha Grande, Brazil

Directory of Open Access Journals (Sweden)

A. F. Paula

Full Text Available The distribution and abundance of azooxanthellate coral Tubastraea Lesson, 1829 were examined at different depths and their slope preference was measured on rocky shores on Ilha Grande, Brazil. Tubastraea is an ahermatypic scleractinian nonindigenous to Brazil, which probably arrived on a ship's hull or oil platform in the late 1980's. The exotic coral was found along a great geographic range of the Canal Central of Ilha Grande, extending over a distance of 25 km. The abundance of Tubastraea was quantified by depth, using three different sampling methods: colony density, visual estimation and intercept points (100 for percentage of cover. Tubastraea showed ample tolerance to temperature and desiccation since it was found more abundantly in very shallow waters (0.1-0.5 m, despite the fact that hard substratum is available at greater depths at all the stations sampled. At most sites, 1 to 5 colonies per 0.25 m² were found most frequently, but occasionally more than 50 colonies were found per 0.25 m², indicating a somewhat gregarious spatial distribution for this coral. The coral Tubastraea was found to occupy slopes of every possible angle in the Canal Central of Ilha Grande, but more colonies were found occupying slopes of 80 to 100°. Therefore, its insensitivity to angles of recruitment and its tolerance for different depths makes it an organism with great ecological tolerance, with a potential to colonize new areas and increase its current range in Brazil's coastal waters.

Habitat selection, facilitation, and biotic settlement cues affect distribution and performance of coral recruits in French Polynesia.

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Price, Nichole

2010-07-01

Habitat selection can determine the distribution and performance of individuals if the precision with which sites are chosen corresponds with exposure to risks or resources. Contrastingly, facilitation can allow persistence of individuals arriving by chance and potentially maladapted to local abiotic conditions. For marine organisms, selection of a permanent attachment site at the end of their larval stage or the presence of a facilitator can be a critical determinant of recruitment success. In coral reef ecosystems, it is well known that settling planula larvae of reef-building corals use coarse environmental cues (i.e., light) for habitat selection. Although laboratory studies suggest that larvae can also use precise biotic cues produced by crustose coralline algae (CCA) to select attachment sites, the ecological consequences of biotic cues for corals are poorly understood in situ. In a field experiment exploring the relative importance of biotic cues and variability in habitat quality to recruitment of hard corals, pocilloporid and acroporid corals recruited more frequently to one species of CCA, Titanoderma prototypum, and significantly less so to other species of CCA; these results are consistent with laboratory assays from other studies. The provision of the biotic cue accurately predicted coral recruitment rates across habitats of varying quality. At the scale of CCA, corals attached to the "preferred" CCA experienced increased survivorship while recruits attached elsewhere had lower colony growth and survivorship. For reef-building corals, the behavioral selection of habitat using chemical cues both reduces the risk of incidental mortality and indicates the presence of a facilitator.

Utilization of Mucus from the Coral Acropora palmata by the Pathogen Serratia marcescens and by Environmental and Coral Commensal Bacteria▿ †

Science.gov (United States)

Krediet, Cory J.; Ritchie, Kim B.; Cohen, Matthew; Lipp, Erin K.; Sutherland, Kathryn Patterson; Teplitski, Max

2009-01-01

In recent years, diseases of corals caused by opportunistic pathogens have become widespread. How opportunistic pathogens establish on coral surfaces, interact with native microbiota, and cause disease is not yet clear. This study compared the utilization of coral mucus by coral-associated commensal bacteria (“Photobacterium mandapamensis” and Halomonas meridiana) and by opportunistic Serratia marcescens pathogens. S. marcescens PDL100 (a pathogen associated with white pox disease of Acroporid corals) grew to higher population densities on components of mucus from the host coral. In an in vitro coculture on mucus from Acropora palmata, S. marcescens PDL100 isolates outgrew coral isolates. The white pox pathogen did not differ from other bacteria in growth on mucus from a nonhost coral, Montastraea faveolata. The ability of S. marcescens to cause disease in acroporid corals may be due, at least in part, to the ability of strain PDL100 to build to higher population numbers within the mucus surface layer of its acroporid host. During growth on mucus from A. palmata, similar glycosidase activities were present in coral commensal bacteria, in S. marcescens PDL100, and in environmental and human isolates of S. marcescens. The temporal regulation of these activities during growth on mucus, however, was distinct in the isolates. During early stages of growth on mucus, enzymatic activities in S. marcescens PDL100 were most similar to those in coral commensals. After overnight incubation on mucus, enzymatic activities in a white pox pathogen were most similar to those in pathogenic Serratia strains isolated from human mucosal surfaces. PMID:19395569

Reconnaissance dating: a new radiocarbon method applied to assessing the temporal distribution of Southern Ocean deep-sea corals

Science.gov (United States)

Burke, Andrea; Robinson, Laura F.; McNichol, Ann P.; Jenkins, William J.; Scanlon, Kathryn M.; Gerlach, Dana S.

2010-01-01

We have developed a rapid 'reconnaissance' method of preparing graphite for 14C/12C analysis. Carbonate (~15 mg) is combusted using an elemental analyzer and the resulting CO2 is converted to graphite using a sealed tube zinc reduction method. Over 85% (n=45 replicates on twenty-one individual corals) of reconnaissance ages measured on corals ranging in age from 500 to 33,000 radiocarbon years (Ryr) are within two standard deviations of ages generated using standard hydrolysis methods on the same corals, and all reconnaissance ages are within 300 Ryr of the standard hydrolysis ages. Replicate measurements on three individual aragonitic corals yielded ages of 1076±35 Ryr (standard deviation; n=5), 10,739±47 Ryr (n=8), and 40,146±3500 Ryr (n=9). No systematic biases were found using different cleaning methods or variable sample sizes. Analysis of 13C/12C was made concurrently with the 14C/12C measurement to correct for natural fractionation and for fractionation during sample processing and analysis. This technique provides a new, rapid method for making accurate, percent-level 14C/12C analyses that may be used to establish the rates and chronology of earth system processes where survey-type modes of age estimation are desirable. For example, applications may include creation of sediment core-top maps, preliminary age models for sediment cores, and growth rate studies of marine organisms such as corals or mollusks. We applied the reconnaissance method to more than 100 solitary deep-sea corals collected in the Drake Passage in the Southern Ocean to investigate their temporal and spatial distribution. The corals used in this study are part of a larger sample set, and the subset that was dated was chosen based on species as opposed to preservation state, so as to exclude obvious temporal biases. Similar to studies in other regions, the distribution of deep-sea corals is not constant through time across the Drake Passage. Most of the corals from the Burdwood Bank

Beneficial Microorganisms for Corals (BMC): Proposed Mechanisms for Coral Health and Resilience.

Science.gov (United States)

Peixoto, Raquel S; Rosado, Phillipe M; Leite, Deborah Catharine de Assis; Rosado, Alexandre S; Bourne, David G

2017-01-01

The symbiotic association between the coral animal and its endosymbiotic dinoflagellate partner Symbiodinium is central to the success of corals. However, an array of other microorganisms associated with coral (i.e., Bacteria, Archaea, Fungi, and viruses) have a complex and intricate role in maintaining homeostasis between corals and Symbiodinium . Corals are sensitive to shifts in the surrounding environmental conditions. One of the most widely reported responses of coral to stressful environmental conditions is bleaching. During this event, corals expel Symbiodinium cells from their gastrodermal tissues upon experiencing extended seawater temperatures above their thermal threshold. An array of other environmental stressors can also destabilize the coral microbiome, resulting in compromised health of the host, which may include disease and mortality in the worst scenario. However, the exact mechanisms by which the coral microbiome supports coral health and increases resilience are poorly understood. Earlier studies of coral microbiology proposed a coral probiotic hypothesis, wherein a dynamic relationship exists between corals and their symbiotic microorganisms, selecting for the coral holobiont that is best suited for the prevailing environmental conditions. Here, we discuss the microbial-host relationships within the coral holobiont, along with their potential roles in maintaining coral health. We propose the term BMC (Beneficial Microorganisms for Corals) to define (specific) symbionts that promote coral health. This term and concept are analogous to the term Plant Growth Promoting Rhizosphere (PGPR), which has been widely explored and manipulated in the agricultural industry for microorganisms that inhabit the rhizosphere and directly or indirectly promote plant growth and development through the production of regulatory signals, antibiotics and nutrients. Additionally, we propose and discuss the potential mechanisms of the effects of BMC on corals, suggesting

Variation in size frequency distribution of coral populations under different fishing pressures in two contrasting locations in the Indian Ocean.

Science.gov (United States)

Grimsditch, G; Pisapia, C; Huck, M; Karisa, J; Obura, D; Sweet, M

2017-10-01

This study aimed to assess how the size-frequency distributions of coral genera varied between reefs under different fishing pressures in two contrasting Indian Ocean locations (the Maldives and East Africa). Using generalized linear mixed models, we were able to demonstrate that complex interactions occurred between coral genera, coral size class and fishing pressure. In both locations, we found Acropora coral species to be more abundant in non-fished compared to fished sites (a pattern which was consistent for nearly all the assessed size classes). Coral genera classified as 'stress tolerant' showed a contrasting pattern i.e. were higher in abundance in fished compared to non-fished sites. Site specific variations were also observed. For example, Maldivian reefs exhibited a significantly higher abundance in all size classes of 'competitive' corals compared to East Africa. This possibly indicates that East African reefs have already been subjected to higher levels of stress and are therefore less suitable environments for 'competitive' corals. This study also highlights the potential structure and composition of reefs under future degradation scenarios, for example with a loss of Acropora corals and an increase in dominance of 'stress tolerant' and 'generalist' coral genera. Copyright © 2017. Published by Elsevier Ltd.

Uptake and distribution of organo-iodine in deep-sea corals.

Science.gov (United States)

Prouty, Nancy G; Roark, E Brendan; Mohon, Leslye M; Chang, Ching-Chih

2018-07-01

Understanding iodine concentration, transport, and bioavailability is essential in evaluating iodine's impact to the environment and its effectiveness as an environmental biogeotracer. While iodine and its radionuclides have proven to be important tracers in geologic and biologic studies, little is known about transport of this element to the deep sea and subsequent uptake in deep-sea coral habitats. Results presented here on deep-sea black coral iodine speciation and iodine isotope variability provides key information on iodine behavior in natural and anthropogenic environments, and its geochemical pathway in the Gulf of Mexico. Organo-iodine is the dominant iodine species in the black corals, demonstrating that binding of iodine to organic matter plays an important role in the transport and transfer of iodine to the deep-sea corals. The identification of growth bands captured in high-resolution scanning electron images (SEM) with synchronous peaks in iodine variability suggest that riverine delivery of terrestrial-derived organo-iodine is the most plausible explanation to account for annual periodicity in the deep-sea coral geochemistry. Whereas previous studies have suggested the presence of annual growth rings in deep-sea corals, this present study provides a mechanism to explain the formation of annual growth bands. Furthermore, deep-sea coral ages based on iodine peak counts agree well with those ages derived from radiocarbon ( 14 C) measurements. These results hold promise for developing chronologies independent of 14 C dating, which is an essential component in constraining reservoir ages and using radiocarbon as a tracer of ocean circulation. Furthermore, the presence of enriched 129 I/ 127 I ratios during the most recent period of skeleton growth is linked to nuclear weapons testing during the 1960s. The sensitivity of the coral skeleton to record changes in surface water 129 I composition provides further evidence that iodine composition and isotope

Uptake and distribution of organo-iodine in deep-sea corals

Science.gov (United States)

Prouty, Nancy G.; Roark, E. Brendan; Mohon, Leslye M.; Chang, Ching-Chih

2018-01-01

Understanding iodine concentration, transport, and bioavailability is essential in evaluating iodine's impact to the environment and its effectiveness as an environmental biogeotracer. While iodine and its radionuclides have proven to be important tracers in geologic and biologic studies, little is known about transport of this element to the deep sea and subsequent uptake in deep-sea coral habitats. Results presented here on deep-sea black coral iodine speciation and iodine isotope variability provides key information on iodine behavior in natural and anthropogenic environments, and its geochemical pathway in the Gulf of Mexico. Organo-iodine is the dominant iodine species in the black corals, demonstrating that binding of iodine to organic matter plays an important role in the transport and transfer of iodine to the deep-sea corals. The identification of growth bands captured in high-resolution scanning electron images (SEM) with synchronous peaks in iodine variability suggest that riverine delivery of terrestrial-derived organo-iodine is the most plausible explanation to account for annual periodicity in the deep-sea coral geochemistry. Whereas previous studies have suggested the presence of annual growth rings in deep-sea corals, this present study provides a mechanism to explain the formation of annual growth bands. Furthermore, deep-sea coral ages based on iodine peak counts agree well with those ages derived from radiocarbon (14C) measurements. These results hold promise for developing chronologies independent of 14C dating, which is an essential component in constraining reservoir ages and using radiocarbon as a tracer of ocean circulation. Furthermore, the presence of enriched 129I/127I ratios during the most recent period of skeleton growth is linked to nuclear weapons testing during the 1960s. The sensitivity of the coral skeleton to record changes in surface water 129I composition provides further evidence that iodine composition and isotope

Sharing the slope: depth partitioning of agariciid corals and associated

NARCIS (Netherlands)

Bongaerts, P.; Frade, P.R.; Ogier, J.J.; Hay, K.B.; van Bleijswijk, J.; Englebert, N.; Vermeij, M.J.A.; Bak, R.P.M.; Visser, P.M.; Hoegh-Guldberg, O.

2013-01-01

Background: Scleractinian corals and their algal endosymbionts (genus Symbiodinium) exhibit distinct bathymetric distributions on coral reefs. Yet, few studies have assessed the evolutionary context of these ecological distributions by exploring the genetic diversity of closely related coral species

ETIOLOGY OF WHITE POX, A LETHAL DISEASE OF THE CARIBBEAN ELKHORN CORAL, ACROPORA PALMATA.

Science.gov (United States)

Populations of the shallow-water Caribbean elkhorn coral, Acropora palmata, are being decimated by white pox disease, with losses in the Florida Keys typically in excess of 70%. Tissue loss is rapid, averaging 2.5 cm2 day-1. A bacterium isolated from diseased A. palmata was shown...

Distribution of gall crabs inhabiting mushroom corals on Semporna reefs, Malaysia

NARCIS (Netherlands)

van der Meij, Sancia E. T.; Hoeksema, Bert W.

Coral reef cryptofauna forms an important component of tropical marine biodiversity, consisting primarily of invertebrates dwelling in and on corals. During a survey carried out around the Semporna peninsula (Sabah, NE Borneo), the occurrence of gall crabs inhabiting mushroom corals was examined on

The carbonate mineralogy and distribution of habitat-forming deep-sea corals in the southwest pacific region

Science.gov (United States)

Bostock, Helen C.; Tracey, Dianne M.; Currie, Kim I.; Dunbar, Gavin B.; Handler, Monica R.; Mikaloff Fletcher, Sara E.; Smith, Abigail M.; Williams, Michael J. M.

2015-06-01

to Ωaragonite of 0.7. With this tolerance for some carbonate undersaturation it is unclear how deep sea habitat-forming corals might respond to future ocean acidification. It is likely that some species/genera will cope better than others. However, future changes in oxygen concentrations and food availability, are also going to have a strong influence on the depth and spatial distribution of deep-sea corals in the southwest Pacific.

Vertical water mass structure in the North Atlantic influences the bathymetric distribution of species in the deep-sea coral genus Paramuricea

Science.gov (United States)

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 understood. Environmental factors, especially depth-related variables including water mass properties, are thought to considerably affect the realized distribution of deep-sea corals. These factors are governed by local and regional oceanographic conditions that directly influence the dispersal of larvae, and therefore affect the ultimate distribution of adult corals. We used molecular barcoding of mitochondrial and nuclear sequences to identify species of octocorals in the genus Paramuricea collected from the Labrador Sea to the Grand Banks of Newfoundland, Canada at depths of 150-1500 m. The results of this study revealed overlapping bathymetric distributions of the Paramuricea species present off the eastern Canadian coast, including the presence of a few cryptic species previously designated as Paramuricea placomus. The distribution of Paramuricea species in the western North Atlantic differs from the Gulf of Mexico, where five Paramuricea species exhibit strong segregation by depth. The different patterns of Paramuricea species in these contrasting biogeographic regions provide insight into how water mass structure may shape species distribution. Investigating Paramuricea prevalence and distribution in conjunction with oceanographic conditions can help demonstrate the factors that generate and maintain deep-sea biodiversity.

CRED REA Coral Health and Disease Assessment at Saipan Island, Marianas Archipelago in 2007

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 8 sites at...

CRED REA Coral Health and Disease Assessment at Uracas Island, Marianas Archipelago in 2007

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 3 sites at...

CRED REA Coral Health and Disease Assessment at Asuncion Island, Marianas Archipelago in 2007

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 3 sites at...

CRED REA Coral Health and Disease Assessment at Rose Island, American Samoa in 2008

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 12 sites at...

CRED REA Coral Health and Disease Assessment at Sarigan Island, Marianas Archipelago in 2007

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 3 sites at...

CRED REA Coral Health and Disease Assessment at Tinian Island, Marianas Archipelago in 2007

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 5 sites at...

CRED REA Coral Health and Disease Assessment at Guguan Island, Marianas Archipelago in 2007

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 3 sites at...

CRED REA Coral Health and Disease Assessment at Swains Atoll, American Samoa in 2008

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 8 sites at...

CRED REA Coral Health and Disease Assessment at Pagan Island, Marianas Archipelago in 2007

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 9 sites at...

CRED REA Coral Health and Disease Assessment at Aguijan Island, Marianas Archipelago in 2007

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 1 sites at...

CRED REA Coral Health and Disease Assessment at Alamagan Island, Marianas Archipelago in 2007

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 3 sites at...

CRED REA Coral Health and Disease Assessment at Agrihan Island, Marianas Archipelago in 2007

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 3 sites at...

CRED REA Coral Health and Disease Assessment at Tutuila Island, American Samoa in 2008

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 23 sites at...

Seasonal prevalence of white plague like disease on the endemic Brazilian reef coral Mussismilia braziliensis Prevalencia estacional de la enfermedad de la plaga blanca en el coral endémico de Brasil Mussismilia braziliensis

Directory of Open Access Journals (Sweden)

Ronaldo Francini-Filho

2010-01-01

Full Text Available The reef coral Mussismilia braziliensis Verril, 1968 is endemic to the eastern Brazilian coast, representing a major reef-building species in the region. This coral is threatened by extinction due to the recent proliferation of a white-plague like (WPL disease. Despite its severe impacts, the environmental factors leading to outbreaks of WPL disease are still poorly understood. This study describes the seasonal prevalence of WPL disease on M. braziliensis in the Abrolhos Bank, on the southern coast of Bahia Brazil. In situ estimates showed that WPL disease was about 4.5 times more prevalent in summer (January 2007, mean sea surface temperature 27.4°C than in winter (July 2007, 25.0°C. This result suggests that the prevalence of WPL disease in M. braziliensis is temperature-dependent, supporting the hypothesis that warmer oceans are facilitating the proliferation of coral diseases worldwide.El coral Mussismilia braziliensis Verril, 1968 es endémico de la costa este de Brasil y representa una de las principales especies constructoras de arrecifes coralinos en dicha region. Este coral se encuentra bajo la amenaza de extincion debido la reciente propagacion de la enfermedad llamada la plaga blanca (PB. Pese los fuertes impactos, los factores ambientales responsables por epidemias de la PB aún son poco conocidos. En este estudio se describe la prevalencia estacional de la PB en M. braziliensis en el Banco de Abrolhos, ubicado en la costa sur de Bahia, Brasil. Estimaciones in situ comprueban que la prevalencia de esta molestia ha sido cerca de 4,5 veces mayor en verano (enero de 2007, temperatura media del agua superficial del mar 27,4°C, que en invierno (julio de 2007; 25,0°C. Este resultado sugiere que la prevalencia de la enfermedad PB en M. braziliensis es dependiente de la temperatura, reforzando la hipótesis de que los océanos mas cálidos estén facilitando la propagacion de enfermedades coralígenas en todo el mundo.

CRED REA Coral Health and Disease Assessment at Rota Island, Marianas Archipelago in 2007

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 6 sites at Rota...

CRED REA Coral Health and Disease Assessment at Oahu, Main Hawaiian Islands in 2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 2 sites at Oahu...

CRED REA Coral Health and Disease Assessment at Maug Island, Marianas Archipelago in 2007

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 9 sites at Maug...

Multi-scale approach for predicting fish species distributions across coral reef seascapes.

Directory of Open Access Journals (Sweden)

Simon J Pittman

Full Text Available 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

Agents of coral mortality on reef formations of the Colombian Pacific.

Science.gov (United States)

Navas-Camacho, Raúl; Rodríguez-Ramírez, Alberto; Reyes-Nivia, María Catalina

2010-05-01

The National Monitoring System for Coral Reefs of Colombia (SIMAC) monitors the impact of some of the most important agents of coral tissue loss (bleaching and/or disease) in the Colombian Pacific coral formations since 1998. Physiological bleaching is among the main results of stress in the area. Signs of coral diseases resembling bacterial bleaching such as White Plague and White Band, were observed in Malpelo and Gorgona islands. Damage to the Pacific gorgonian Pacifigorgia spp., similar to those produced by Aspergillosis in Caribbean corals, was detected in Utria Bay. The presence of tumors in colonies of massive corals was also recorded. Even though coral diseases are globally widespread, their occurrence in American Pacific reefs has been poorly documented to date.

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

Science.gov (United States)

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.

Colony size-frequency distribution of pocilloporid juvenile corals along a natural environmental gradient in the Red Sea

KAUST Repository

Lozano-Corté s, Diego; Berumen, Michael L.

2015-01-01

Coral colony size-frequency distributions can be used to assess population responses to local environmental conditions and disturbances. In this study, we surveyed juvenile pocilloporids, herbivorous fish densities, and algal cover in the central

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

Directory of Open Access Journals (Sweden)

Greta S Aeby

2011-02-01

Full Text Available 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.

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

Science.gov (United States)

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

Lectins stain cells differentially in the coral, Montipora capitata

Science.gov (United States)

Work, Thierry M.; Farah, Yael

2014-01-01

A limitation in our understanding of coral disease pathology and cellular pathogenesis is a lack of reagents to characterize coral cells. We evaluated the utility of plant lectins to stain tissues of a dominant coral, Montipora capitata, from Hawaii. Of 22 lectins evaluated, nine of these stained structures in the upper or basal body wall of corals. Specific structures revealed by lectins that were not considered distinct or evident on routine hematoxylin and eosin sections of coral tissues included apical and basal granules in gastrodermis and epidermis, cnidoglandular tract and actinopharynx cell surface membranes, capsules of mature holotrichous isorhizas, and perivitelline and periseminal cells. Plant lectins could prove useful to further our understanding of coral physiology, anatomy, cell biology, and disease pathogenesis.

CRED REA Coral Health and Disease Assessment at Hawaii Island, Main Hawaiian Islands in 2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 17 sites at...

CRED REA Coral Health and Disease Assessment at Molokai Island, Main Hawaiian Islands in 2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 3 sites at...

CRED REA Coral Health and Disease Assessment at Midway Atoll, Northwestern Hawaiian Islands in 2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 9 sites at...

CRED REA Coral Health and Disease Assessment at Ofu-Olosega Island, American Samoa in 2008

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 10 sites at...

CRED REA Coral Health and Disease Assessment at Lehua Rock, Main Hawaiian Islands in 2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 3 sites at...

CRED REA Coral Health and Disease Assessment at Maui Island, Main Hawaiian Islands in 2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 11 sites at...

CRED REA Coral Health and Disease Assessment at Necker Island, Northwestern Hawaiian Islands in 2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 2 sites at...

CRED REA Coral Health and Disease Assessment at Lisianski Island, Northwestern Hawaiian Islands in 2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 9 sites at...

CRED REA Coral Health and Disease Assessment at Laysan Island, Northwestern Hawaiian Islands in 2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 3 sites at...

CRED REA Coral Health and Disease Assessment at Kaula Rock, Main Hawaiian Islands in 2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 2 sites at...

CRED REA Coral Health and Disease Assessment at Niihau Island, Main Hawaiian Islands in 2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 6 sites at...

CRED REA Coral Health and Disease Assessment at Lanai Island, Main Hawaiian Islands in 2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 6 sites at...

Agents of coral mortality on reef formations of the Colombian Pacific

Directory of Open Access Journals (Sweden)

Raúl Navas-Camacho

2010-05-01

Full Text Available The National Monitoring System for Coral Reefs of Colombia (SIMAC monitors the impact of some of the most important agents of coral tissue loss (bleaching and/or disease in the Colombian Pacific coral formations since 1998. Physiological bleaching is among the main results of stress in the area. Signs of coral diseases resembling bacterial bleaching such as White Plague and White Band, were observed in Malpelo and Gorgona islands. Damage to the Pacific gorgonian Pacifigorgia spp., similar to those produced by Aspergillosis in Caribbean corals, was detected in Utría Bay. The presence of tumors in colonies of massive corals was also recorded. Even though coral diseases are globally widespread, their occurrence in American Pacific reefs has been poorly documented to date. Rev. Biol. Trop. 58 (Suppl. 1: 133-138. Epub 2010 May 01.

CRED REA Coral Health and Disease Assessment at Kure Atoll, Northwestern Hawaiian Islands in 2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 9 sites at Kure...

Distribution of cold-water corals in the Whittard Canyon, NE Atlantic Ocean

OpenAIRE

Morris, Kirsty J.; Tyler, Paul A.; Masson, Doug G.; Huvenne, Veerle A.I.; Rogers, Alex D.

2013-01-01

The deep-sea floor occupies about 60% of the surface of the planet and is covered mainly by fine sediments. Most studies of deep-sea benthic fauna therefore have concentrated on soft sediments with little sampling of hard substrata, such as rocky outcrops in submarine canyons. Here we assess the distribution and abundance of cold-water corals within the Whittard Canyon (NE Atlantic) using video footage from the ROV Isis. Abundances per 100 m of video transect were calculated and mapped using ...

CRED REA Coral Health and Disease Assessment at Ta'u Island, American Samoa in 2008

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 9 sites at Ta'u...

Temporal dynamics of black band disease affecting pillar coral ( Dendrogyra cylindrus) following two consecutive hyperthermal events on the Florida Reef Tract

Science.gov (United States)

Lewis, Cynthia L.; Neely, Karen L.; Richardson, Laurie L.; Rodriguez-Lanetty, Mauricio

2017-06-01

Black band disease (BBD) affects many coral species worldwide and is considered a major contributor to the decline of reef-building coral. On the Florida Reef Tract BBD is most prevalent during summer and early fall when water temperatures exceed 29 °C. BBD is rarely reported in pillar coral ( Dendrogyra cylindrus) throughout the Caribbean, and here we document for the first time the appearance of the disease in this species on Florida reefs. The highest monthly BBD prevalence in the D. cylindrus population were 4.7% in 2014 and 6.8% in 2015. In each year, BBD appeared immediately following a hyperthermal bleaching event, which raises concern as hyperthermal seawater anomalies become more frequent.

Diversity and distribution of symbiodinium associated with seven common coral species in the Chagos Archipelago, central Indian Ocean.

Directory of Open Access Journals (Sweden)

Sung-Yin Yang

Full Text Available 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.

Forecasting decadal changes in sea surface temperatures and coral bleaching within a Caribbean coral reef

Science.gov (United States)

Li, Angang; Reidenbach, Matthew A.

2014-09-01

Elevated sea surface temperature (SST) caused by global warming is one of the major threats to coral reefs. While increased SST has been shown to negatively affect the health of coral reefs by increasing rates of coral bleaching, how changes to atmospheric heating impact SST distributions, modified by local flow environments, has been less understood. This study aimed to simulate future water flow patterns and water surface heating in response to increased air temperature within a coral reef system in Bocas del Toro, Panama, located within the Caribbean Sea. Water flow and SST were modeled using the Delft3D-FLOWcomputer simulation package. Locally measured physical parameters, including bathymetry, astronomic tidal forcing, and coral habitat distribution were input into the model and water flow, and SST was simulated over a four-month period under present day, as well as projected warming scenarios in 2020s, 2050s, and 2080s. Changes in SST, and hence the thermal stress to corals, were quantified by degree heating weeks. Results showed that present-day reported bleaching sites were consistent with localized regions of continuous high SST. Regions with highest SST were located within shallow coastal sites adjacent to the mainland or within the interior of the bay, and characterized by low currents with high water retention times. Under projected increases in SSTs, shallow reef areas in low flow regions were found to be hot spots for future bleaching.

Comparative Profiling of coral symbiont communities from the Caribbean, Indo-Pacific, and Arabian Seas

KAUST Repository

Arif, Chatchanit

2014-12-01

Coral reef ecosystems are in rapid decline due to global and local anthropogenic factors. Being among the most diverse ecosystems on Earth, a loss will decrease species diversity, and remove food source for people along the coast. The coral together with its symbionts (i.e. Symbiodinium, bacteria, and other microorganisms) is called the ‘coral holobiont’. The coral host offers its associated symbionts suitable habitats and nutrients, while Symbiodinium and coral-associated bacteria provide the host with photosynthates and vital nutrients. Association of corals with certain types of Symbiodinium and bacteria confer coral stress tolerance, and lack or loss of these symbionts coincides with diseased or bleached corals. However, a detailed understanding of the coral holobiont diversity and structure in regard to diseases and health states or across global scales is missing. This dissertation addressed coral-associated symbiont diversity, specifically of Symbiodinium and bacteria, in various coral species from different geographic locations and different health states. The main aims were (1) to expand the scope of existing technologies, (2) to establish a standardized framework to facilitate comparison of symbiont assemblages over coral species and sites, (3) to assess Symbiodinium diversity in the Arabian Seas, and (4) to elucidate whether coral health states have conserved bacterial footprints. In summary, a next generation sequencing pipeline for Symbiodinium diversity typing of the ITS2 marker is developed and applied to describe Symbiodinium diversity in corals around the Arabian Peninsula. The data show that corals in the Arabian Seas are dominated by a single Symbiodinium type, but harbor a rich variety of types in low abundant. Further, association with different Symbiodinium types is structured according to geographic locations. In addition, the application of 16S rRNA gene microarrays to investigate how differences in microbiome structure relate to

Distribution and bioavailability of cadmium in ornithogenic coral-sand sediments of the Xisha archipelago, South China Sea

International Nuclear Information System (INIS)

Liu Xiaodong; Lou Chuangneng; Xu Liqiang; Sun Liguang

2012-01-01

Total cadmium (Cd) concentrations in four ornithogenic coral-sand sedimentary profiles displayed a strong positive correlation with guano-derived phosphorus, but had no correlation with plant-originated organic matter in the top sediments. These results indicate that the total Cd distributions were predominantly controlled by guano input. Bioavailable Cd and zinc (Zn) had a greater input rate in the top sediments with respect to total Cd and total Zn, and a positive correlation with total organic carbon (TOC) derived from plant humus. Multi-regression analysis showed that the total Cd and TOC explained over 80% of the variation of bioavailable Cd, suggesting that both guano and plant inputs could significantly influence the distribution of bioavailable Cd, and that plant biocycling processes contribute more to the recent increase of bioavailable Cd. A pollution assessment indicates that the Yongle archipelago is moderately to strongly polluted with guano-derived Cd. - Guano and plant biocycling processes can exert different influences on the distributions of total Cd and bioavailable Cd in coral-sand ornithogenic sediments.

From cholera to corals: Viruses as drivers of virulence in a major coral bacterial pathogen

KAUST Repository

Weynberg, Karen D.

2015-12-08

Disease is an increasing threat to reef-building corals. One of the few identified pathogens of coral disease is the bacterium Vibrio coralliilyticus. In Vibrio cholerae, infection by a bacterial virus (bacteriophage) results in the conversion of non-pathogenic strains to pathogenic strains and this can lead to cholera pandemics. Pathogenicity islands encoded in the V. cholerae genome play an important role in pathogenesis. Here we analyse five whole genome sequences of V. coralliilyticus to examine whether virulence is similarly driven by horizontally acquired elements. We demonstrate that bacteriophage genomes encoding toxin genes with homology to those found in pathogenic V. cholerae are integrated in V. coralliilyticus genomes. Virulence factors located on chromosomal pathogenicity islands also exist in some strains of V. coralliilyticus. The presence of these genetic signatures indicates virulence in V. coralliilyticus is driven by prophages and other horizontally acquired elements. Screening for pathogens of coral disease should target conserved regions in these elements.

From cholera to corals: Viruses as drivers of virulence in a major coral bacterial pathogen

KAUST Repository

Weynberg, Karen D.; Voolstra, Christian R.; Neave, Matthew J.; Buerger, Patrick; van Oppen, Madeleine J. H.

2015-01-01

Disease is an increasing threat to reef-building corals. One of the few identified pathogens of coral disease is the bacterium Vibrio coralliilyticus. In Vibrio cholerae, infection by a bacterial virus (bacteriophage) results in the conversion of non-pathogenic strains to pathogenic strains and this can lead to cholera pandemics. Pathogenicity islands encoded in the V. cholerae genome play an important role in pathogenesis. Here we analyse five whole genome sequences of V. coralliilyticus to examine whether virulence is similarly driven by horizontally acquired elements. We demonstrate that bacteriophage genomes encoding toxin genes with homology to those found in pathogenic V. cholerae are integrated in V. coralliilyticus genomes. Virulence factors located on chromosomal pathogenicity islands also exist in some strains of V. coralliilyticus. The presence of these genetic signatures indicates virulence in V. coralliilyticus is driven by prophages and other horizontally acquired elements. Screening for pathogens of coral disease should target conserved regions in these elements.

CRED REA Coral Health and Disease Assessment at Johnston Atoll, Pacific Remote Island Areas in 2008

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 6 sites at...

CRED REA Coral Health and Disease Assessment at Jarvis Island, Pacific Remote Island Areas in 2008

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 9 sites at...

CRED REA Coral Health and Disease Assessment at Wake Atoll, Pacific Remote Island Areas in 2007

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 12 sites at...

CRED REA Coral Health and Disease Assessment at Kingman Reef, Pacific Remote Island Areas in 2008

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 11 sites at...

CRED REA Coral Health and Disease Assessment at French Frigate Shoals, Northwestern Hawaiian Islands in 2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 10 sites at...

Coral health on reefs near mining sites in New Caledonia.

Science.gov (United States)

Heintz, T; Haapkylä, J; Gilbert, A

2015-07-23

Coral health data are poorly documented in New Caledonia, particularly from reefs chronically subject to anthropogenic and natural runoff. We investigated patterns of coral disease and non-disease conditions on reefs situated downstream of mining sites off the coast of New Caledonia. Surveys were conducted in March 2013 at 2 locations along the west coast and 2 locations along the east coast of the main island. Only 2 coral diseases were detected: growth anomalies and white syndrome. The most prevalent signs of compromised health at each location were sediment damage and algal overgrowth. These results support earlier findings that sedimentation and turbidity are major threats to in-shore reefs in New Caledonia. The Poritidae-dominated west coast locations were more subject to sediment damage, algal overgrowth and growth anomalies compared to the Acroporidae-dominated east coast locations. If growth form and resistance of coral hosts influence these results, differences in environmental conditions including hydro-dynamism between locations may also contribute to these outputs. Our results highlight the importance of combining coral health surveys with measurements of coral cover when assessing the health status of a reef, as reefs with high coral cover may have a high prevalence of corals demonstrating signs of compromised health.

Adaptation of cyanobacteria to the sulfide-rich microenvironment of black band disease of coral.

Science.gov (United States)

Myers, Jamie L; Richardson, Laurie L

2009-02-01

Black band disease (BBD) is a cyanobacteria-dominated microbial mat that migrates across living coral colonies lysing coral tissue and leaving behind exposed coral skeleton. The mat is sulfide-rich due to the presence of sulfate-reducing bacteria, integral members of the BBD microbial community, and the sulfide they produce is lethal to corals. The effect of sulfide, normally toxic to cyanobacteria, on the photosynthetic capabilities of five BBD cyanobacterial isolates of the genera Geitlerinema (3), Leptolyngbya (1), and Oscillatoria (1) and six non-BBD cyanobacteria of the genera Leptolyngbya (3), Pseudanabaena (2), and Phormidium (1) was examined. Photosynthetic experiments were performed by measuring the photoincorporation of [(14)C] NaHCO(3) under the following conditions: (1) aerobic (no sulfide), (2) anaerobic with 0.5 mM sulfide, and (3) anaerobic with 0.5 mM sulfide and 10 microM 3-(3',4'-dichlorophenyl)-1,1-dimethylurea (DCMU). All five BBD cyanobacterial isolates tolerated sulfide by conducting sulfide-resistant oxygenic photosynthesis. Five of the non-BBD cyanobacterial isolates did not tolerate sulfide, although one Pseudanabaena isolate continued to photosynthesize in the presence of sulfide at a considerably reduced rate. None of the isolates conducted anoxygenic photosynthesis with sulfide as an electron donor. This is the first report on the physiology of a culture of Oscillatoria sp. found globally in BBD.

Big Data Approaches To Coral-Microbe Symbiosis

Science.gov (United States)

Zaneveld, J.; Pollock, F. J.; McMinds, R.; Smith, S.; Payet, J.; Hanna, B.; Welsh, R.; Foster, A.; Ohdera, A.; Shantz, A. A.; Burkepile, D. E.; Maynard, J. A.; Medina, M.; Vega Thurber, R.

2016-02-01

Coral reefs face increasing challenges worldwide, threatened by overfishing and nutrient pollution, which drive growth of algal competitors of corals, and periods of extreme temperature, which drive mass coral bleaching. I will discuss two projects that examine how coral's complex relationships with microorganisms affect the response of coral colonies and coral species to environmental challenge. Microbiological studies have documented key roles for coral's microbial symbionts in energy harvest and defense against pathogens. However, the evolutionary history of corals and their microbes is little studied. As part of the Global Coral Microbiome Project, we are characterizing bacterial, archaeal, fungal, and Symbiodinium diversity across >1400 DNA samples from all major groups of corals, collected from 15 locations worldwide. This collection will allow us to ask how coral- microbe associations evolved over evolutionary time, and to determine whether microbial symbiosis helps predict the relative vulnerability of certain coral species to environmental stress. In the second project, we experimentally characterized how the long-term effects of human impacts such as overfishing and nutrient pollution influence coral-microbe symbiosis. We conducted a three-year field experiment in the Florida Keys applying nutrient pollution or simulated overfishing to reef plots, and traced the effects on reef communities, coral microbiomes, and coral health. The results show that extremes of temperature and algal competition destabilize coral microbiomes, increasing pathogen blooms, coral disease, and coral death. Surprisingly, these local stressors interacted strongly with thermal stress: the greatest microbiome disruption, and >80% of coral mortality happened in the hottest periods. Thus, overfishing and nutrient pollution may interact with increased climate-driven episodes of sub-bleaching thermal stress to increase coral mortality by disrupt reef communities down to microbial scales.

Phylogenetic diversity of actinobacteria associated with soft coral Alcyonium gracllimum and stony coral Tubastraea coccinea in the East China Sea.

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Yang, Shan; Sun, Wei; Tang, Cen; Jin, Liling; Zhang, Fengli; Li, Zhiyong

2013-07-01

Actinobacteria are widely distributed in the marine environment. To date, few studies have been performed to explore the coral-associated Actinobacteria, and little is known about the diversity of coral-associated Actinobacteria. In this study, the actinobacterial diversity associated with one soft coral Alcyonium gracllimum and one stony coral Tubastraea coccinea collected from the East China Sea was investigated using both culture-independent and culture-dependent approaches. A total of 19 actinobacterial genera were detected in these two corals, among which nine genera (Corynebacterium, Dietzia, Gordonia, Kocuria, Microbacterium, Micrococcus, Mycobacterium, Streptomyces, and Candidatus Microthrix) were common, three genera (Cellulomonas, Dermatophilus, and Janibacter) were unique to the soft coral, and seven genera (Brevibacterium, Dermacoccus, Leucobacter, Micromonospora, Nocardioides, Rhodococcus, and Serinicoccus) were unique to the stony coral. This finding suggested that highly diverse Actinobacteria were associated with different types of corals. In particular, five actinobacterial genera (Cellulomonas, Dermacoccus, Gordonia, Serinicoccus, and Candidatus Microthrix) were recovered from corals for the first time, extending the known diversity of coral-associated Actinobacteria. This study shows that soft and stony corals host diverse Actinobacteria and can serve as a new source of marine actinomycetes.

Complex interactions between potentially pathogenic, opportunistic, and resident bacteria emerge during infection on a reef-building coral.

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Gignoux-Wolfsohn, Sarah A; Aronson, Felicia M; Vollmer, Steven V

2017-07-01

Increased bacterial diversity on diseased corals can obscure disease etiology and complicate our understanding of pathogenesis. To untangle microbes that may cause white band disease signs from microbes responding to disease, we inoculated healthy Acropora cervicornis corals with an infectious dose from visibly diseased corals. We sampled these dosed corals and healthy controls over time for sequencing of the bacterial 16S region. Endozoicomonas were associated with healthy fragments from 4/10 colonies, dominating microbiomes before dosing and decreasing over time only in corals that displayed disease signs, suggesting a role in disease resistance. We grouped disease-associated bacteria by when they increased in abundance (primary vs secondary) and whether they originated in the dose (colonizers) or the previously healthy corals (responders). We found that all primary responders increased in all dosed corals regardless of final disease state and are therefore unlikely to cause disease signs. In contrast, primary colonizers in the families Pasteurellaceae and Francisellaceae increased solely in dosed corals that ultimately displayed disease signs, and may be infectious foreign bacteria involved in the development of disease signs. Moving away from a static comparison of diseased and healthy bacterial communities, we provide a framework to identify key players in other coral diseases. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

PATHOGENECITY OF GROUPER SLEEPY DISEASE IRIDOVIRUS (GSDIV: Megalocytivirus, FAMILY Iridoviridae TO CORAL TROUT GROUPER Plectrophomus leopardus

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Ketut Mahardika

2009-12-01

Full Text Available Grouper sleepy disease iridovirus (GSDIV, a member of the genus Megalocytivirus in the family Iridoviridae, has been known to cause large scale mortalities resulting in severe economic losses in grouper industries in south-east Asia including Indonesia. In this study, experimental infection of coral trout grouper Plectrophomus indicus with GSDIV was performed to evaluate the viral pathogenecity to this fish species. After virus exposure, the mortalities of coral trout grouper injected with primary and 10-1 dilution of spleen homogenates derived from tiger grouper Epinephelus fuscoguttatus were 100% and 90%, respectively. Histopathology revealed that moribund fish receiving GSDIV inoculum displayed massive formation of enlarged cells in the spleen and hematopoitic tissues. Under electron microscopy, the enlarged cells were observed as inclusion body bearing cells (IBCs and necrotic cells allowing virus propagation within an intracytoplasmic virus assembly site (VAS. GSDIV virions were 167-200 nm in size. These findings confirmed that GSDIV has severe pathogenicity to coral trout grouper and IBCs as well as necrotic cells were determined to be the pathognomonic sign of megalocytivirus-infected coral trout grouper.

Repopulation of Zooxanthellae in the Caribbean corals Montastraea annularis and M. faveolata following experimental and disease-associated bleaching.

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Toller, W W; Rowan, R; Knowlton, N

2001-12-01

Caribbean corals of the Montastraea annularis species complex associate with four taxa of symbiotic dinoflagellates (zooxanthellae; genus Symbiodinium) in ecologically predictable patterns. To investigate the resilience of these host-zooxanthella associations, we conducted field experiments in which we experimentally reduced the numbers of zooxanthellae (by transplanting to shallow water or by shading) and then allowed treated corals to recover. When depletion was not extreme, recovering corals generally contained the same types of zooxanthellae as they did prior to treatment. After severe depletion, however, recovering corals were always repopulated by zooxanthellae atypical for their habitat (and in some cases atypical for the coral species). These unusual zooxanthellar associations were often (but not always) established in experimentally bleached tissues even when adjacent tissues were untreated. Atypical zooxanthellae were also observed in bleached tissues of unmanipulated Montastraea with yellow-blotch disease. In colonies where unusual associations were established, the original taxa of zooxanthellae were not detected even 9 months after the end of treatment. These observations suggest that zooxanthellae in Montastraea range from fugitive opportunists and stress-tolerant generalists (Symbiodinium A and E) to narrowly adapted specialists (Symbiodinium B and C), and may undergo succession.

Life on the edge: corals in mangroves and climate change

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Rogers, Caroline S.; Herlan, James J.

2012-01-01

Coral diseases have played a major role in the degradation of coral reefs in the Caribbean, including those in the US Virgin Islands (USVI). In 2005, bleaching affected reefs throughout the Caribbean, and was especially severe on USVI reefs. Some corals began to regain their color as water temperatures cooled, but an outbreak of disease (primarily white plague) led to losses of over 60% of the total live coral cover. Montastraea annularis, the most abundant coral, was disproportionately affected, and decreased in relative abundance. The threatened species Acropora palmata bleached for the first time on record in the USVI but suffered less bleaching and less mortality from disease than M. annularis. Acropora palmata and M. annularis are the two most significant species in the USVI because of their structural role in the architecture of the reefs, the large size of their colonies, and their complex morphology. The future of the USVI reefs depends largely on their fate. Acropora palmata is more likely to recover than M. annularis for many reasons, including its faster growth rate, and its lower vulnerability to bleaching and disease.

Biogeography of azooxanthellate corals in the Caribbean and surrounding areas

Science.gov (United States)

Dawson, J.

2002-04-01

Biogeographic patterns for azooxanthellate corals are not as well known as those of zooxanthellate (primarily reef-building) corals. I analyzed occurrences of 129 species of azooxanthellate corals in 19 geopolitical regions in the Caribbean and surrounding areas. I performed an unweighted pair-group method with arithmetic averages (UPGMA) cluster analysis using Bray-Curtis' similarity measure on the complete data set and shallow- and deep-water subsets of the data. The results indicate two provinces, each with a widespread (tropical and subtropical distributions) component to its fauna. One province has a tropical and primarily insular component to it, while the other has a subtropical and primarily continental component. By contrast, zooxanthellate corals have a uniform faunal composition throughout the Caribbean. Moreover, zooxanthellate corals have half as many species in the Caribbean as the azooxanthellate corals even though their global diversities are equal. These differences in diversity and geographic distribution patterns should be considered when developing conservation strategies.

Caribbean corals house shared and host-specific microbial symbionts over time and space.

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Chu, Nathaniel D; Vollmer, Steven V

2016-08-01

The rise of coral diseases has triggered a surge of interest in coral microbial communities. But to fully understand how the coral microbiome may cause or respond to disease, we must first understand structure and variation in the healthy coral microbiome. We used 16S rRNA sequencing to characterize the microbiomes of 100 healthy coral colonies from six Caribbean coral species (Acropora cervicornis, A. palmata, Diploria labyrinthiformis, Diploria strigosa, Porites astreoides and P. furcata) across four reefs and three time points over 1 year. We found host species to be the strongest driver of coral microbiome structure across site and time. Analysis of the core microbiome revealed remarkable similarity in the bacterial taxa represented across coral hosts and many bacterial phylotypes shared across all corals sampled. Some of these widespread bacterial taxa have been identified in Pacific corals, indicating that a core coral microbiome may extend across oceans. Core bacterial phylotypes that were unique to each coral were taxonomically diverse, suggesting that different coral hosts provide persistent, divergent niches for bacteria. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

CRED REA Coral Health and Disease Assessment at at Palmyra Atoll, Pacific Remote Island Areas in 2008

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National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 14 sites at...

CRED REA Coral Health and Disease Assessment at Pearl and Hermes Atoll, Northwestern Hawaiian Islands in 2006

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National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 13 sites at...

Environmental drivers of distribution and reef development of the Mediterranean coral Cladocora caespitosa

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Chefaoui, Rosa M.; Casado-Amezúa, Pilar; Templado, José

2017-12-01

Cladocora caespitosa is the only Mediterranean scleractinian similar to tropical reef-building corals. While this species is part of the recent fossil history of the Mediterranean Sea, it is currently considered endangered due to its decline during the last decades. Environmental factors affecting the distribution and persistence of extensive bank reefs of this endemic species across its whole geographic range are poorly understood. In this study, we examined the environmental response of C. caespitosa and its main types of assemblages using ecological niche modeling and ordination analysis. We also predicted other suitable areas for the occurrence of the species and assessed the conservation effectiveness of Mediterranean marine protected areas (MPAs) for this coral. We found that phosphate concentration and wave height were factors affecting both the occurrence of this versatile species and the distribution of its extensive bioconstructions in the Mediterranean Sea. A set of factors (diffuse attenuation coefficient, calcite and nitrate concentrations, mean wave height, sea surface temperature, and shape of the coast) likely act as environmental barriers preventing the species from expansion to the Atlantic Ocean and the Black Sea. Uncertainties in our large-scale statistical results and departures from previous physiological and ecological studies are also discussed under an integrative perspective. This study reveals that Mediterranean MPAs encompass eight of the ten banks and 16 of the 21 beds of C. caespitosa. Preservation of water clarity by avoiding phosphate discharges may improve the protection of this emblematic species.

Mapping cold-water coral habitats at different scales within the Northern Ionian Sea (Central Mediterranean: an assessment of coral coverage and associated vulnerability.

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Alessandra Savini

Full Text Available In this study, we mapped the distribution of Cold-Water Coral (CWC habitats on the northern Ionian Margin (Mediterranean Sea, with an emphasis on assessing coral coverage at various spatial scales over an area of 2,000 km(2 between 120 and 1,400 m of water depth. Our work made use of a set of data obtained from ship-based research surveys. Multi-scale seafloor mapping data, video inspections, and previous results from sediment samples were integrated and analyzed using Geographic Information System (GIS-based tools. Results obtained from the application of spatial and textural analytical techniques to acoustic meso-scale maps (i.e. a Digital Terrain Model (DTM of the seafloor at a 40 m grid cell size and associated terrain parameters and large-scale maps (i.e. Side-Scan Sonar (SSS mosaics of 1 m in resolution ground-truthed using underwater video observations were integrated and revealed that, at the meso-scale level, the main morphological pattern (i.e. the aggregation of mound-like features associated with CWC habitat occurrences was widespread over a total area of 600 km(2. Single coral mounds were isolated from the DTM and represented the geomorphic proxies used to model coral distributions within the investigated area. Coral mounds spanned a total area of 68 km(2 where different coral facies (characterized using video analyses and mapped on SSS mosaics represent the dominant macro-habitat. We also mapped and classified anthropogenic threats that were identifiable within the examined videos, and, here, discuss their relationship to the mapped distribution of coral habitats and mounds. The combined results (from multi-scale habitat mapping and observations of the distribution of anthropogenic threats provide the first quantitative assessment of CWC coverage for a Mediterranean province and document the relevant role of seafloor geomorphology in influencing habitat vulnerability to different types of human pressures.

Mapping cold-water coral habitats at different scales within the Northern Ionian Sea (Central Mediterranean): an assessment of coral coverage and associated vulnerability.

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Savini, Alessandra; Vertino, Agostina; Marchese, Fabio; Beuck, Lydia; Freiwald, André

2014-01-01

In this study, we mapped the distribution of Cold-Water Coral (CWC) habitats on the northern Ionian Margin (Mediterranean Sea), with an emphasis on assessing coral coverage at various spatial scales over an area of 2,000 km(2) between 120 and 1,400 m of water depth. Our work made use of a set of data obtained from ship-based research surveys. Multi-scale seafloor mapping data, video inspections, and previous results from sediment samples were integrated and analyzed using Geographic Information System (GIS)-based tools. Results obtained from the application of spatial and textural analytical techniques to acoustic meso-scale maps (i.e. a Digital Terrain Model (DTM) of the seafloor at a 40 m grid cell size and associated terrain parameters) and large-scale maps (i.e. Side-Scan Sonar (SSS) mosaics of 1 m in resolution ground-truthed using underwater video observations) were integrated and revealed that, at the meso-scale level, the main morphological pattern (i.e. the aggregation of mound-like features) associated with CWC habitat occurrences was widespread over a total area of 600 km(2). Single coral mounds were isolated from the DTM and represented the geomorphic proxies used to model coral distributions within the investigated area. Coral mounds spanned a total area of 68 km(2) where different coral facies (characterized using video analyses and mapped on SSS mosaics) represent the dominant macro-habitat. We also mapped and classified anthropogenic threats that were identifiable within the examined videos, and, here, discuss their relationship to the mapped distribution of coral habitats and mounds. The combined results (from multi-scale habitat mapping and observations of the distribution of anthropogenic threats) provide the first quantitative assessment of CWC coverage for a Mediterranean province and document the relevant role of seafloor geomorphology in influencing habitat vulnerability to different types of human pressures.

Unseen players shape benthic competition on coral reefs.

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Barott, Katie L; Rohwer, Forest L

2012-12-01

Recent work has shown that hydrophilic and hydrophobic organic matter (OM) from algae disrupts the function of the coral holobiont and promotes the invasion of opportunistic pathogens, leading to coral morbidity and mortality. Here we refer to these dynamics as the (3)DAM [dissolved organic matter (DOM), direct contact, disease, algae and microbes] model. There is considerable complexity in coral-algae interactions; turf algae and macroalgae promote heterotrophic microbial overgrowth of coral, macroalgae also directly harm the corals via hydrophobic OM, whereas crustose coralline algae generally encourage benign microbial communities. In addition, complex flow patterns transport OM and pathogens from algae to downstream corals, and direct algal contact enhances their delivery. These invisible players (microbes, viruses, and OM) are important drivers of coral reefs because they have non-linear responses to disturbances and are the first to change in response to perturbations, providing near real-time trajectories for a coral reef, a vital metric for conservation and restoration. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

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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

Human sewage identified as likely source of white pox disease of the threatened Caribbean elkhorn coral, Acropora palmata.

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Sutherland, Kathryn Patterson; Porter, James W; Turner, Jeffrey W; Thomas, Brian J; Looney, Erin E; Luna, Trevor P; Meyers, Meredith K; Futch, J Carrie; Lipp, Erin K

2010-05-01

Caribbean elkhorn coral, Acropora palmata, has been decimated in recent years, resulting in the listing of this species as threatened under the United States Endangered Species Act. A major contributing factor in the decline of this iconic species is white pox disease. In 2002, we identified the faecal enterobacterium, Serratia marcescens, as an etiological agent for white pox. During outbreaks in 2003 a unique strain of S. marcescens was identified in both human sewage and white pox lesions. This strain (PDR60) was also identified from corallivorious snails (Coralliophila abbreviata), reef water, and two non-acroporid coral species, Siderastrea siderea and Solenastrea bournoni. Identification of PDR60 in sewage, diseased Acropora palmata and other reef invertebrates within a discrete time frame suggests a causal link between white pox and sewage contamination on reefs and supports the conclusion that humans are a likely source of this disease.

PhyloChip™ microarray comparison of sampling methods used for coral microbial ecology

Science.gov (United States)

Kellogg, Christina A.; Piceno, Yvette M.; Tom, Lauren M.; DeSantis, Todd Z.; Zawada, David G.; Andersen, Gary L.

2012-01-01

Interest in coral microbial ecology has been increasing steadily over the last decade, yet standardized methods of sample collection still have not been defined. Two methods were compared for their ability to sample coral-associated microbial communities: tissue punches and foam swabs, the latter being less invasive and preferred by reef managers. Four colonies of star coral, Montastraea annularis, were sampled in the Dry Tortugas National Park (two healthy and two with white plague disease). The PhyloChip™ G3 microarray was used to assess microbial community structure of amplified 16S rRNA gene sequences. Samples clustered based on methodology rather than coral colony. Punch samples from healthy and diseased corals were distinct. All swab samples clustered closely together with the seawater control and did not group according to the health state of the corals. Although more microbial taxa were detected by the swab method, there is a much larger overlap between the water control and swab samples than punch samples, suggesting some of the additional diversity is due to contamination from water absorbed by the swab. While swabs are useful for noninvasive studies of the coral surface mucus layer, these results show that they are not optimal for studies of coral disease.

CRED REA Coral Health and Disease Assessment at Howland Island, Phoenix Islands, Pacific Remote Island Areas in 2008

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 5 sites around...

CRED REA Coral Health and Disease Assessment at Baker Island, Phoenix Islands, Pacific Remote Island Areas in 2008

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 4 sites around...

Bleaching, disease and recovery in the threatened scleractinian coral Acropora palmata in St. John, US Virgin Islands: 2003-2010

Science.gov (United States)

Rogers, C.S.; Muller, E.M.

2012-01-01

A long-term study of the scleractinian coral Acropora palmata in the US Virgin Islands (USVI) showed that diseases, particularly white pox, are limiting the recovery of this threatened species. Colonies of A. palmata in Haulover Bay, within Virgin Islands National Park, St. John, were examined monthly in situ for signs of disease and other stressors from January 2003 through December 2009. During the study, 89.9 % of the colonies (n = 69) exhibited disease, including white pox (87 %), white band (13 %), and unknown (9 %). Monthly disease prevalence ranged from 0 to 57 %, and disease was the most significant cause of complete colony mortality (n = 17). A positive correlation was found between water temperature and disease prevalence, but not incidence. Annual average disease prevalence and incidence remained constant during the study. Colonies generally showed an increase in the estimated amount of total living tissue from growth, but 25 (36.2 %) of the colonies died. Acropora palmata bleached in the USVI for the first time during the 2005 Caribbean bleaching event. Only one of the 23 colonies that bleached appeared to die directly from bleaching. In 2005, corals that bleached had greater disease prevalence than those that did not bleach. Just over half (52 %) of the colonies incurred some physical damage. Monitoring of fragments (broken branches) that were generated by physical damage through June 2007 showed that 46.1 % died and 28.4 % remained alive; the fragments that attached to the substrate survived longer than those that did not. Recent surveys showed an increase in the total number of colonies within the reef area, formed from both asexual and sexual reproduction. Genotype analysis of 48 of the originally monitored corals indicated that 43 grew from sexual recruits supporting the conclusion that both asexual and sexual reproduction are contributing to an increase in colony density at this site.

Bleaching, disease and recovery in the threatened scleractinian coral Acropora palmata in St. John, US Virgin Islands: 2003-2010

Science.gov (United States)

Rogers, C. S.; Muller, E. M.

2012-09-01

A long-term study of the scleractinian coral Acropora palmata in the US Virgin Islands (USVI) showed that diseases, particularly white pox, are limiting the recovery of this threatened species. Colonies of A. palmata in Haulover Bay, within Virgin Islands National Park, St. John, were examined monthly in situ for signs of disease and other stressors from January 2003 through December 2009. During the study, 89.9 % of the colonies ( n = 69) exhibited disease, including white pox (87 %), white band (13 %), and unknown (9 %). Monthly disease prevalence ranged from 0 to 57 %, and disease was the most significant cause of complete colony mortality ( n = 17). A positive correlation was found between water temperature and disease prevalence, but not incidence. Annual average disease prevalence and incidence remained constant during the study. Colonies generally showed an increase in the estimated amount of total living tissue from growth, but 25 (36.2 %) of the colonies died. Acropora palmata bleached in the USVI for the first time during the 2005 Caribbean bleaching event. Only one of the 23 colonies that bleached appeared to die directly from bleaching. In 2005, corals that bleached had greater disease prevalence than those that did not bleach. Just over half (52 %) of the colonies incurred some physical damage. Monitoring of fragments (broken branches) that were generated by physical damage through June 2007 showed that 46.1 % died and 28.4 % remained alive; the fragments that attached to the substrate survived longer than those that did not. Recent surveys showed an increase in the total number of colonies within the reef area, formed from both asexual and sexual reproduction. Genotype analysis of 48 of the originally monitored corals indicated that 43 grew from sexual recruits supporting the conclusion that both asexual and sexual reproduction are contributing to an increase in colony density at this site.

Large-scale coral recruitment patterns on Mona Island, Puerto Rico: evidence of a transitional community trajectory after massive coral bleaching and mortality

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Edwin A. Hernández-Delgado

2014-09-01

Full Text Available Coral reefs have largely declined across the northeastern Caribbean following the 2005 massive bleaching event. Climate change-related sea surface warming and coral disease outbreaks of a white plague-like syndrome and of yellow band disease (YBD have caused significant coral decline affecting massive reef building species (i.e., Orbicella annularis species complex which show no apparent signs of recovery through larval sexual recruitment. We addressed coral recruit densities across three spur and groove reef locations along the western shelf of remote Mona Island, Puerto Rico: Punta Capitán (PCA, Pasa de Las Carmelitas (PLC, and Las Carmelitas-South (LCS. Data were collected during November 2012 along 93 haphazard transects across three depth zones (<5m, 5-10m, 10-15m. A total of 32 coral species (9 octocorals, 1 hydrocoral, 22 scleractinians were documented among the recruit community. Communities had low densities and dominance by short-lived brooder species seven years after the 2005 event. Mean coral recruit density ranged from 1.2 to 10.5/m2 at PCA, 6.3 to 7.2/m² at LCS, 4.5 to 9.5/m² at PLC. Differences in coral recruit community structure can be attributed to slight variation in percent macroalgal cover and composition as study sites had nearly similar benthic spatial heterogeneity. Dominance by ephemeral coral species was widespread. Recovery of largely declining massive reef-building species such as the O. annularis species complex was limited or non-existent. The lack of recovery could be the combined result of several mechanisms involving climate change, YBD disease, macroalgae, fishing, urchins and Mona Island’s reefs limited connectivity to other reef systems. There is also for rehabilitation of fish trophic structure, with emphasis in recovering herbivore guilds and depleted populations of D. antillarum. Failing to recognize the importance of ecosystem-based management and resilience rehabilitation may deem remote coral reefs

Predicted deep-sea coral habitat suitability for the U.S. West coast.

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John M Guinotte

Full Text Available Regional scale habitat suitability models provide finer scale resolution and more focused predictions of where organisms may occur. Previous modelling approaches have focused primarily on local and/or global scales, while regional scale models have been relatively few. In this study, regional scale predictive habitat models are presented for deep-sea corals for the U.S. West Coast (California, Oregon and Washington. Model results are intended to aid in future research or mapping efforts and to assess potential coral habitat suitability both within and outside existing bottom trawl closures (i.e. Essential Fish Habitat (EFH and identify suitable habitat within U.S. National Marine Sanctuaries (NMS. Deep-sea coral habitat suitability was modelled at 500 m×500 m spatial resolution using a range of physical, chemical and environmental variables known or thought to influence the distribution of deep-sea corals. Using a spatial partitioning cross-validation approach, maximum entropy models identified slope, temperature, salinity and depth as important predictors for most deep-sea coral taxa. Large areas of highly suitable deep-sea coral habitat were predicted both within and outside of existing bottom trawl closures and NMS boundaries. Predicted habitat suitability over regional scales are not currently able to identify coral areas with pin point accuracy and probably overpredict actual coral distribution due to model limitations and unincorporated variables (i.e. data on distribution of hard substrate that are known to limit their distribution. Predicted habitat results should be used in conjunction with multibeam bathymetry, geological mapping and other tools to guide future research efforts to areas with the highest probability of harboring deep-sea corals. Field validation of predicted habitat is needed to quantify model accuracy, particularly in areas that have not been sampled.

Vertical and horizontal distribution of Desmophyllum dianthus in Comau Fjord, Chile: a cold-water coral thriving at low pH.

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Fillinger, Laura; Richter, Claudio

2013-01-01

Cold-water corals provide an important habitat for a rich fauna along the continental margins and slopes. Although these azooxanthellate corals are considered particularly sensitive to ocean acidification, their responses to natural variations in pH and aragonite saturation are largely unknown due to the difficulty of studying their ecology in deep waters. Previous SCUBA investigations have shown an exceptionally shallow population of the cold-water coral Desmophyllum dianthus in near-surface waters of Comau Fjord, a stratified 480 m deep basin in northern Chilean Patagonia with suboxic deep waters. Here, we use a remotely operated vehicle to quantitatively investigate the distribution of D. dianthus and its physico-chemical drivers in so far uncharted naturally acidified waters. Remarkably, D. dianthus was ubiquitous throughout the fjord, but particularly abundant between 20 and 280 m depth in a pH range of 8.4 to 7.4. The persistence of individuals in aragonite-undersaturated waters suggests that present-day D. dianthus in Comau Fjord may show pre-acclimation or pre-adaptation to conditions of ocean acidification predicted to reach over 70% of the known deep-sea coral locations by the end of the century.

Vertical and horizontal distribution of Desmophyllum dianthus in Comau Fjord, Chile: a cold-water coral thriving at low pH

Directory of Open Access Journals (Sweden)

Laura Fillinger

2013-10-01

Full Text Available Cold-water corals provide an important habitat for a rich fauna along the continental margins and slopes. Although these azooxanthellate corals are considered particularly sensitive to ocean acidification, their responses to natural variations in pH and aragonite saturation are largely unknown due to the difficulty of studying their ecology in deep waters. Previous SCUBA investigations have shown an exceptionally shallow population of the cold-water coral Desmophyllum dianthus in near-surface waters of Comau Fjord, a stratified 480 m deep basin in northern Chilean Patagonia with suboxic deep waters. Here, we use a remotely operated vehicle to quantitatively investigate the distribution of D. dianthus and its physico-chemical drivers in so far uncharted naturally acidified waters. Remarkably, D. dianthus was ubiquitous throughout the fjord, but particularly abundant between 20 and 280 m depth in a pH range of 8.4 to 7.4. The persistence of individuals in aragonite-undersaturated waters suggests that present-day D. dianthus in Comau Fjord may show pre-acclimation or pre-adaptation to conditions of ocean acidification predicted to reach over 70% of the known deep-sea coral locations by the end of the century.

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.

Science.gov (United States)

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. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

CORAL CONDITION: HOW TO FATHOM THE DECLINE OF CORAL REEF ECOSYSTEMS

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Coral reefs have experienced unprecedented levels of bleaching, disease and mortality during the last three decades. The goal of EPA-ORD research is to identify the culpable stressors in different species, reefs and regions using integrated field and laboratory studies.

The Role of Shipyard Pollutants in Structuring Coral Reef Microbial Communities: Monitoring Environmental Change and the Potential Causes of Coral Disease

Science.gov (United States)

2006-06-01

718 plant cell wall polysaccharides and simplified quantitative determination of their 719 neutral monosaccharides by gas-liquid chromatography. JAgr...analyses of amino acid and monosaccharide composition were used to determine how coral mucus varied among the sampled coral colonies. The 615 N value of... polysaccharides , and lipids that comprise 52 coral mucus make it a suitable environment for microbial growth (Ducklow, 1979a, 53 1979b; Ferrier-Pages

Coral Reef Remote Sensing: Helping Managers Protect Reefs in a Changing Climate

Science.gov (United States)

Eakin, C.; Liu, G.; Li, J.; Muller-Karger, F. E.; Heron, S. F.; Gledhill, D. K.; Christensen, T.; Rauenzahn, J.; Morgan, J.; Parker, B. A.; Skirving, W. J.; Nim, C.; Burgess, T.; Strong, A. E.

2010-12-01

Climate change and ocean acidification are already having severe impacts on coral reef ecosystems. Warming oceans have caused corals to bleach, or expel their symbiotic algae (zooxanthellae) with alarming frequency and severity and have contributed to a rise in coral infectious diseases. Ocean acidification is reducing the availability of carbonate ions needed by corals and many other marine organisms to build structural components like skeletons and shells and may already be slowing the coral growth. These two impacts are already killing corals and slowing reef growth, reducing biodiversity and the structure needed to provide crucial ecosystem services. NOAA’s Coral Reef Watch (CRW) uses a combination of satellite data, in situ observations, and models to provide coral reef managers, scientists, and others with information needed to monitor threats to coral reefs. The advance notice provided by remote sensing and models allows resource managers to protect corals, coral reefs, and the services they provide, although managers often encounter barriers to implementation of adaptation strategies. This talk will focus on application of NOAA’s satellite and model-based tools that monitor the risk of mass coral bleaching on a global scale, ocean acidification in the Caribbean, and coral disease outbreaks in selected regions, as well as CRW work to train managers in their use, and barriers to taking action to adapt to climate change. As both anthropogenic CO2 and temperatures will continue to rise, local actions to protect reefs are becoming even more important.

Mesophotic coral-reef environments depress the reproduction of the coral Paramontastraea peresi in the Red Sea

Science.gov (United States)

Feldman, Bar; Shlesinger, Tom; Loya, Yossi

2018-03-01

With more than 450 studied species, coral reproduction is a well-known research field. However, the vast majority of coral reproduction research has focused exclusively on shallow reefs. The incentive for the present study was: (1) the recent accelerated global degradation of coral reefs; (2) the growing interest in mesophotic coral ecosystems (MCEs; 30-120 m depth) and their potential to serve as a larval source for shallow reefs; and (3) the lack of information on MCE coral reproduction. Here, we compare the reproduction and ecology of the depth-generalist coral Paramontastraea peresi between shallow (5-10 m) and mesophotic (40-45 m) habitats in the Gulf of Eilat/Aqaba, Red Sea. Field surveys were conducted to assess the living cover, abundance, and size frequency distribution of P. peresi. Four to six colonies from each habitat were sampled monthly between April 2015 and January 2017, and the gametogenesis cycles, fecundity, and oocyte sizes were measured. The reproductive cycle in the MCEs was shorter than in the shallow reef. Despite having larger polyps, the mesophotic colonies contained significantly smaller and fewer oocytes per polyp. In spite of the relatively stable environmental conditions of the MCEs, which may contribute to coral survival, scarcity of sunlight is probably a major energetic impediment to investment in reproduction by P. peresi at mesophotic depths. Further intensive reproductive studies in mesophotic reefs are thus required to assess the ability of corals in this environment to reproduce and constitute a larval source for depleted shallow-water reefs.

The ;Sardinian cold-water coral province; in the context of the Mediterranean coral ecosystems

Science.gov (United States)

Taviani, M.; Angeletti, L.; Canese, S.; Cannas, R.; Cardone, F.; Cau, A.; Cau, A. B.; Follesa, M. C.; Marchese, F.; Montagna, P.; Tessarolo, C.

2017-11-01

A new cold-water coral (CWC) province has been identified in the Mediterranean Sea in the Capo Spartivento canyon system offshore the southern coast of Sardinia. The 'Sardinia cold-water coral province' is characterized in the Nora canyon by a spectacular coral growth dominated by the branching scleractinian Madrepora oculata at a depth of 380-460 m. The general biohermal frame is strengthened by the common occurrence of the solitary scleractinian Desmophyllum dianthus and the occasional presence of Lophelia pertusa. As documented by Remotely Operated Vehicle survey, this area is a hotspot of megafaunal diversity hosting among other also live specimens of the deep oyster Neopycnodonte zibrowii. The new coral province is located between the central Mediterranean CWC provinces (Bari Canyon, Santa Maria di Leuca, South Malta) and the western and northern ones (Melilla, Catalan-Provençal-Ligurian canyons). As for all the best developed CWC situations in the present Mediterranean Sea, the new Sardinian province is clearly influenced by Levantine Intermediate Water which appears to be a main driver for CWC distribution and viability in this basin.

Occurrence and distribution of Polycyclic aromatic hydrocarbons (PAHs) in seawater, sediments and corals from Hainan Island, China.

Science.gov (United States)

Xiang, Nan; Jiang, Chunxia; Yang, Tinghan; Li, Ping; Wang, Haihua; Xie, Yanli; Li, Sennan; Zhou, Hailong; Diao, Xiaoping

2018-05-15

The levels of 16 US EPA priority polycyclic aromatic hydrocarbons (PAHs) were investigated in corals, ambient seawater and sediments of Hainan Island, China, using gas chromatography - mass spectrometry (GC-MS). The total PAHs (∑PAHs) concentrations ranged from 273.79 to 407.82ng/L in seawater. Besides, the concentrations of ∑PAHs in corals 333.88-727.03ng/g dw) were markedly (P corals. The highest concentration of ∑PAHs was detected at site S2 in Pavona decussate, which also bore the highest ∑PAHs levels in both seawater and sediments. The massive corals were more enriched with PAHs than the branching corals. Although 2 and 3-ring PAHs were predominant and accounted for 69.27-80.46% of the ∑PAHs in corals and ambient environment, the levels of high molecular weight (HMW) PAHs (4-6 ring) in corals also demonstrated their potential dangers for corals and organisms around coral reefs. Biota-sediment accumulation factor (BSAF) refers to an index of the pollutant absorbed by aquatic organisms from the surrounding sediments. The poor correlation between log BSAF and log K ow (hydrophobicity) indicated that PAHs in corals maybe not bioaccumulate from the ambient sediments but through pathways like absorbing from seawater, symbiosis, and feeding. Based on our data, long-term ecological monitoring in typical coral reef ecosystems combined with ecotoxicological tests of PAHs on corals is necessary to determine the impacts of PAHs on coral reefs. Copyright © 2018 Elsevier Inc. All rights reserved.

Epimicrobiota associated with the decay and recovery of Orbicella corals exhibiting Dark Spot Syndrome

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Julie L Meyer

2016-06-01

Full Text Available Dark Spot Syndrome (DSS is one of the most common diseases of boulder corals in the Caribbean. It presents as sunken brown lesions in coral tissue, which can spread quickly over coral colonies. With this study, we tested the hypothesis that similar to other coral diseases, DSS is a dysbiosis characterized by global shifts in the coral microbiome. Because Black Band Disease (BBD was sometimes found following DSS lesions, we also tested the hypothesis that DSS is a precursor of BBD. To track disease initiation and progression 24 coral colonies were tagged. Of them five Orbicella annularis corals and three O. faveolata corals exhibited DSS lesions at tagging. Microbiota of lesions and apparently healthy tissues from DSS-affected corals over the course of 18 months were collected. Final visual assessment showed that five of eight corals incurred substantial tissue loss while two corals remained stable and one appeared to recover from DSS lesions. Illumina sequencing of the V6 region of bacterial 16S rRNA genes demonstrated no significant differences in bacterial community composition associated with healthy tissue or DSS lesions. The epimicrobiomes of both healthy tissue and DSS lesions contained high relative abundances of Operational Taxonomic Units (OTUs assigned to Halomonas, an unclassified gammaproteobacterial genus, Moritella, an unclassified Rhodobacteraceae genus, Renibacterium, Pseudomonas, and Acinetobacter. The relative abundance of bacterial taxa was not significantly different between samples when grouped by tissue type (healthy tissue vs. DSS lesion, coral species, collection month, or the overall outcome of DSS-affected corals (substantial tissue loss vs. stable/recovered. Two of the tagged corals with substantial tissue loss also developed BBD during the 18-month sampling period. The bacterial community of the BBD layer was distinct from both healthy tissue and DSS lesions, with high relative abundances of the presumed BBD pathogen

Spatial distribution of benthic macroorganisms on reef flats at Porto de Galinhas Beach (northeastern Brazil, with special focus on corals and calcified hydroids

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Juliana Imenis Barradas

2010-06-01

Full Text Available Despite their ecological and social-economic importance, coral reefs are under constant threat and thus require proper management practices. Data on the spatial structure of these ecosystems are essential for good quality conservation projects in such areas. This study aimed to quantitatively analyze the spatial distribution of benthic macroorganisms from the reef environment of Porto de Galinhas Beach, with special focus on its corals and calcified hydroids. Reef flats of the area were surveyed by scuba diving, using 10m line transects. A high cover of macroalgae was verified, averaging 53% of the observations. Zoanthids were the second most representative group (11%. A total of 173 colonies of corals and calcified hydroids were observed and 40% of these colonies were partially or totally bleached.

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

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Roberta M Bonaldo

Full Text Available 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.

Distinct Bacterial Communities Associated with Massive and Branching Scleractinian Corals and Potential Linkages to Coral Susceptibility to Thermal or Cold Stress

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Jiayuan Liang

2017-06-01

Full Text Available It is well known that different coral species have different tolerances to thermal or cold stress, which is presumed to be related to the density of Symbiodinium. However, the intrinsic factors between stress-tolerant characteristics and coral-associated bacteria are rarely studied. In this study, 16 massive coral and 9 branching coral colonies from 6 families, 10 genera, and 18 species were collected at the same time and location (Xinyi Reef in the South China Sea to investigate the bacterial communities. The results of an alpha diversity analysis showed that bacterial diversities associated with massive corals were generally higher than those with branching corals at different taxonomic levels (phylum, class, order, and so on. In addition, hierarchical clustering tree and PCoA analyses showed that coral species were clustered into two large groups according to the similarity of bacterial communities. Group I consisted of massive Goniastrea, Plesiastrea, Leptastrea, Platygyra, Echinopora, Porites, and Leptoria, and group II consisted of branching Acropora and Pocillopora. These findings suggested that both massive corals and branching corals have their own preference for the choice of associated bacteria, which may be involved in observed differences in thermal/cold tolerances. Further analysis found that 55 bacterial phyla, including 43 formally described phyla and 12 candidate phyla, were detected in these coral species. Among them, 52 phyla were recovered from the massive coral group, and 46 phyla were recovered from the branching coral group. Formally described coral pathogens have not been detected in these coral species, suggesting that they are less likely to be threatened by disease in this geographic area. This study highlights a clear relationship between the high complexity of bacterial community associated with coral, skeletal morphology of coral and potentially tolerances to thermal or cold stress.

Metagenomic analysis indicates that stressors induce production of herpes-like viruses in the coral Porites compressa

OpenAIRE

Vega Thurber, Rebecca L.; Barott, Katie L.; Hall, Dana; Liu, Hong; Rodriguez-Mueller, Beltran; Desnues, Christelle; Edwards, Robert A.; Haynes, Matthew; Angly, Florent E.; Wegley, Linda; Rohwer, Forest L.

2008-01-01

During the last several decades corals have been in decline and at least one-third of all coral species are now threatened with extinction. Coral disease has been a major contributor to this threat, but little is known about the responsible pathogens. To date most research has focused on bacterial and fungal diseases; however, viruses may also be important for coral health. Using a combination of empirical viral metagenomics and real-time PCR, we show that Porites compressa corals contain a s...

Coral pathogens identified for White Syndrome (WS epizootics in the Indo-Pacific.

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Meir Sussman

Full Text Available BACKGROUND: White Syndrome (WS, a general term for scleractinian coral diseases with acute signs of advancing tissue lesions often resulting in total colony mortality, has been reported from numerous locations throughout the Indo-Pacific, constituting a growing threat to coral reef ecosystems. METHODOLOGY/PRINCIPAL FINDINGS: Bacterial isolates were obtained from corals displaying disease signs at three ws outbreak sites: Nikko Bay in the Republic of Palau, Nelly Bay in the central Great Barrier Reef (GBR and Majuro Atoll in the Republic of the Marshall Islands, and used in laboratory-based infection trials to satisfy Henle-Koch's postulates, Evan's rules and Hill's criteria for establishing causality. Infected colonies produced similar signs to those observed in the field following exposure to bacterial concentrations of 1x10(6 cells ml(-1. Phylogenetic 16S rRNA gene analysis demonstrated that all six pathogens identified in this study were members of the gamma-Proteobacteria family Vibrionacae, each with greater than 98% sequence identity with the previously characterized coral bleaching pathogen Vibrio coralliilyticus. Screening for proteolytic activity of more than 150 coral derived bacterial isolates by a biochemical assay and specific primers for a Vibrio family zinc-metalloprotease demonstrated a significant association between the presence of isolates capable of proteolytic activity and observed disease signs. CONCLUSION/SIGNIFICANCE: This is the first study to provide evidence for the involvement of a unique taxonomic group of bacterial pathogens in the aetiology of Indo-Pacific coral diseases affecting multiple coral species at multiple locations. Results from this study strongly suggest the need for further investigation of bacterial proteolytic enzymes as possible virulence factors involved in Vibrio associated acute coral infections.

Caribbean yellow band disease compromises the activity of catalase and glutathione S-transferase in the reef-building coral Orbicella faveolata exposed to anthracene.

Science.gov (United States)

Montilla, Luis Miguel; Ramos, Ruth; García, Elia; Cróquer, Aldo

2016-05-03

Healthy and diseased corals are threatened by different anthropogenic sources, such as pollution, a problem expected to become more severe in the near future. Despite the fact that coastal pollution and coral diseases might represent a serious threat to coral reef health, there is a paucity of controlled experiments showing whether the response of diseased and healthy corals to xenobiotics differs. In this study, we exposed healthy and Caribbean yellow band disease (CYBD)-affected Orbicella faveolata colonies to 3 sublethal concentrations of anthracene to test if enzymatic responses to this hydrocarbon were compromised in CYBD-affected tissues. For this, a 2-factorial fully orthogonal design was used in a controlled laboratory bioassay, using tissue condition (2 levels: apparently healthy and diseased) and pollutant concentration (4 levels: experimental control, 10, 30 and 100 ppb concentration) as fixed factors. A permutation-based ANOVA (PERMANOVA) was used to test the effects of condition and concentration on the specific activity of 3 enzymatic biomarkers: catalase, glutathione S-transferase, and glutathione peroxidase. We found a significant interaction between the concentration of anthracene and the colony condition for catalase (Pseudo-F = 3.84, df = 3, p < 0.05) and glutathione S-transferase (Pseudo-F = 3.29, df = 3, p < 0.05). Moreover, our results indicated that the enzymatic response to anthracene in CYBD-affected tissues was compromised, as the activity of these enzymes decreased 3- to 4-fold compared to healthy tissues. These results suggest that under a potential scenario of increasing hydrocarbon coastal pollution, colonies of O. faveolata affected with CYBD might become more vulnerable to the deleterious effects of chemical pollution.

Permanent 'phase shifts' or reversible declines in coral cover? Lack of recovery of two coral reefs in St. John, US Virgin Islands

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Rogers, C.S.; Miller, J.

2006-01-01

Caribbean coral reefs have changed dramatically in the last 3 to 4 decades, with significant loss of coral cover and increases in algae. Here we present trends in benthic cover from 1989 to 2003 at 2 reefs (Lameshur Reef and Newfound Reef) off St. John, US Virgin Islands (USVI). Coral cover has declined in the fore-reef zones at both sites, and no recovery is evident. At Lameshur Reef, Hurricane Hugo (1989) caused significant physical damage and loss of coral. We suggest that macroalgae rapidly colonized new substrate made available by this storm and have hindered or prevented growth of adult corals, as well as settlement and survival of new coral recruits. Overfishing of herbivorous fishes in the USVI and loss of shelter for these fishes because of major storms has presumably reduced the levels of herbivory that formerly controlled algal abundance. Coral cover declined at Newfound Reef from 1999 to 2000, most likely because of coral diseases. The trends that we have documented, loss of coral followed by no evidence of recovery, appear similar to findings from other studies in the Caribbean. We need to focus on functional shifts in the resilience of coral reefs that result in their inability to recover from natural and human-caused stressors. ?? Inter-Research 2006.

Ecological Processes and Contemporary Coral Reef Management

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Angela Dikou

2010-05-01

Full Text Available Top-down controls of complex foodwebs maintain the balance among the critical groups of corals, algae, and herbivores, thus allowing the persistence of corals reefs as three-dimensional, biogenic structures with high biodiversity, heterogeneity, resistance, resilience and connectivity, and the delivery of essential goods and services to societies. On contemporary reefs world-wide, however, top-down controls have been weakened due to reduction in herbivory levels (overfishing or disease outbreak while bottom-up controls have increased due to water quality degradation (increase in sediment and nutrient load and climate forcing (seawater warming and acidification leading to algal-dominated alternate benthic states of coral reefs, which are indicative of a trajectory towards ecological extinction. Management to reverse common trajectories of degradation for coral reefs necessitates a shift from optimization in marine resource use and conservation towards building socio-economic resilience into coral reef systems while attending to the most manageable human impacts (fishing and water quality and the global-scale causes (climate change.

Lithifying Microbes Associated to Coral Rubbles

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Beltran, Y.

2015-12-01

Microbial communities taking part in calcium carbonate lithification processes are particularly relevant to coral reef formation in as much as this lithification allows the stabilization of secondary reef structure. This second framework promotes long-term permanence of the reef, favoring the establishment of macro-reef builders, including corals. The reef-bacterial crusts formed by microbial communities are composed of magnesium calcite. Although prokaryotes are not proper calcifiers, carbonate precipitation can be induced by their metabolic activity and EPS production. Coral reefs are rapidly declining due to several variables associated to environmental change. Specifically in the Caribbean, stony coral Acropora palmata have suffered damage due to diseases, bleaching and storms. Some reports show that in highly disturbed areas wide ridges of reef rubbles are formed by biological and physical lithification. In this study we explore microbial diversity associated to lithified rubbles left after the great decline of reef-building A. palmata.

Warm-water coral reefs and climate change.

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Spalding, Mark D; Brown, Barbara E

2015-11-13

Coral reefs are highly dynamic ecosystems that are regularly exposed to natural perturbations. Human activities have increased the range, intensity, and frequency of disturbance to reefs. Threats such as overfishing and pollution are being compounded by climate change, notably warming and ocean acidification. Elevated temperatures are driving increasingly frequent bleaching events that can lead to the loss of both coral cover and reef structural complexity. There remains considerable variability in the distribution of threats and in the ability of reefs to survive or recover from such disturbances. Without significant emissions reductions, however, the future of coral reefs is increasingly bleak. Copyright © 2015, American Association for the Advancement of Science.

Evolutionary insights into scleractinian corals using comparative genomic hybridizations.

KAUST Repository

Aranda, Manuel

2012-09-21

Coral reefs belong to the most ecologically and economically important ecosystems on our planet. Yet, they are under steady decline worldwide due to rising sea surface temperatures, disease, and pollution. Understanding the molecular impact of these stressors on different coral species is imperative in order to predict how coral populations will respond to this continued disturbance. The use of molecular tools such as microarrays has provided deep insight into the molecular stress response of corals. Here, we have performed comparative genomic hybridizations (CGH) with different coral species to an Acropora palmata microarray platform containing 13,546 cDNA clones in order to identify potentially rapidly evolving genes and to determine the suitability of existing microarray platforms for use in gene expression studies (via heterologous hybridization).

Evolutionary insights into scleractinian corals using comparative genomic hybridizations.

KAUST Repository

Aranda, Manuel; DeSalvo, Michael K; Bayer, Till; Medina, Monica; Voolstra, Christian R.

2012-01-01

Coral reefs belong to the most ecologically and economically important ecosystems on our planet. Yet, they are under steady decline worldwide due to rising sea surface temperatures, disease, and pollution. Understanding the molecular impact of these stressors on different coral species is imperative in order to predict how coral populations will respond to this continued disturbance. The use of molecular tools such as microarrays has provided deep insight into the molecular stress response of corals. Here, we have performed comparative genomic hybridizations (CGH) with different coral species to an Acropora palmata microarray platform containing 13,546 cDNA clones in order to identify potentially rapidly evolving genes and to determine the suitability of existing microarray platforms for use in gene expression studies (via heterologous hybridization).

Weak prezygotic isolating mechanisms in threatened Caribbean Acropora corals.

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Nicole D Fogarty

Full Text Available The Caribbean corals, Acropora palmata and A. cervicornis, recently have undergone drastic declines primarily as a result of disease. Previous molecular studies have demonstrated that these species form a hybrid (A. prolifera that varies in abundance throughout the range of the parental distribution. There is variable unidirectional introgression across loci and sites of A. palmata genes flowing into A. cervicornis. Here we examine the efficacy of prezygotic reproductive isolating mechanisms within these corals including spawning times and choice and no-choice fertilization crosses. We show that these species have subtly different mean but overlapping spawning times, suggesting that temporal isolation is likely not an effective barrier to hybridization. We found species-specific differences in gametic incompatibilities. Acropora palmata eggs were relatively resistant to hybridization, especially when conspecific sperm are available to outcompete heterospecific sperm. Acropora cervicornis eggs demonstrated no evidence for gametic incompatibility and no evidence of reduced viability after aging four hours. This asymmetry in compatibility matches previous genetic data on unidirectional introgression.

Weak prezygotic isolating mechanisms in threatened Caribbean Acropora corals.

Science.gov (United States)

Fogarty, Nicole D; Vollmer, Steven V; Levitan, Don R

2012-01-01

The Caribbean corals, Acropora palmata and A. cervicornis, recently have undergone drastic declines primarily as a result of disease. Previous molecular studies have demonstrated that these species form a hybrid (A. prolifera) that varies in abundance throughout the range of the parental distribution. There is variable unidirectional introgression across loci and sites of A. palmata genes flowing into A. cervicornis. Here we examine the efficacy of prezygotic reproductive isolating mechanisms within these corals including spawning times and choice and no-choice fertilization crosses. We show that these species have subtly different mean but overlapping spawning times, suggesting that temporal isolation is likely not an effective barrier to hybridization. We found species-specific differences in gametic incompatibilities. Acropora palmata eggs were relatively resistant to hybridization, especially when conspecific sperm are available to outcompete heterospecific sperm. Acropora cervicornis eggs demonstrated no evidence for gametic incompatibility and no evidence of reduced viability after aging four hours. This asymmetry in compatibility matches previous genetic data on unidirectional introgression.

New directions in coral reef microbial ecology.

Science.gov (United States)

Garren, Melissa; Azam, Farooq

2012-04-01

Microbial processes largely control the health and resilience of coral reef ecosystems, and new technologies have led to an exciting wave of discovery regarding the mechanisms by which microbial communities support the functioning of these incredibly diverse and valuable systems. There are three questions at the forefront of discovery: What mechanisms underlie coral reef health and resilience? How do environmental and anthropogenic pressures affect ecosystem function? What is the ecology of microbial diseases of corals? The goal is to understand the functioning of coral reefs as integrated systems from microbes and molecules to regional and ocean-basin scale ecosystems to enable accurate predictions of resilience and responses to perturbations such as climate change and eutrophication. This review outlines recent discoveries regarding the microbial ecology of different microenvironments within coral ecosystems, and highlights research directions that take advantage of new technologies to build a quantitative and mechanistic understanding of how coral health is connected through microbial processes to its surrounding environment. The time is ripe for natural resource managers and microbial ecologists to work together to create an integrated understanding of coral reef functioning. In the context of long-term survival and conservation of reefs, the need for this work is immediate. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

Global microbialization of coral reefs.

Science.gov (United States)

Haas, Andreas F; Fairoz, Mohamed F M; Kelly, Linda W; Nelson, Craig E; Dinsdale, Elizabeth A; Edwards, Robert A; Giles, Steve; Hatay, Mark; Hisakawa, Nao; Knowles, Ben; Lim, Yan Wei; Maughan, Heather; Pantos, Olga; Roach, Ty N F; Sanchez, Savannah E; Silveira, Cynthia B; Sandin, Stuart; Smith, Jennifer E; Rohwer, Forest

2016-04-25

Microbialization refers to the observed shift in ecosystem trophic structure towards higher microbial biomass and energy use. On coral reefs, the proximal causes of microbialization are overfishing and eutrophication, both of which facilitate enhanced growth of fleshy algae, conferring a competitive advantage over calcifying corals and coralline algae. The proposed mechanism for this competitive advantage is the DDAM positive feedback loop (dissolved organic carbon (DOC), disease, algae, microorganism), where DOC released by ungrazed fleshy algae supports copiotrophic, potentially pathogenic bacterial communities, ultimately harming corals and maintaining algal competitive dominance. Using an unprecedented data set of >400 samples from 60 coral reef sites, we show that the central DDAM predictions are consistent across three ocean basins. Reef algal cover is positively correlated with lower concentrations of DOC and higher microbial abundances. On turf and fleshy macroalgal-rich reefs, higher relative abundances of copiotrophic microbial taxa were identified. These microbial communities shift their metabolic potential for carbohydrate degradation from the more energy efficient Embden-Meyerhof-Parnas pathway on coral-dominated reefs to the less efficient Entner-Doudoroff and pentose phosphate pathways on algal-dominated reefs. This 'yield-to-power' switch by microorganism directly threatens reefs via increased hypoxia and greater CO2 release from the microbial respiration of DOC.

Trend in coral-algal phase shift in the Mandapam group of islands, Gulf of Mannar Marine Biosphere Reserve, India

Science.gov (United States)

Machendiranathan, M.; Senthilnathan, L.; Ranith, R.; Saravanakumar, A.; Thangaradjou, T.; Choudhry, S. B.; Sasamal, S. K.

2016-12-01

The present study revealed proliferation of macro-algae modifying coral reef ecosystems in a different manner due to diseases and sedimentations in the Mandapam group of islands in the Gulf of Mannar. Benthic surveys were conducted with major attack of seven coral reefs diseases with high sedimentation rate, nine species of fleshy macro-algae ( Turbinaria ornata, Turbinaria conaides, Caulerpa scalpelliformis, Caulerpa racemosa, Kappaphycus alvarezii, Padina gymnosphora, Sargassum wightii, Ulva reticulata and Calurpa lentillifera) proliferation against major corals life forms (Acropora branching, Acropora digitate, Acropora tabulate, coral massive, coral submassive, coral foliose and coral encrusting). The results confirm that diseased corals most favor to macro-algae growth (15.27%) rather than the sedimentation covered corals (8.24 %). In the degradation of coral life forms, massive corals were more highly damaged (7.05%) than any other forms. Within a short period of time (May to September), coral coverage shrank to 17.4% from 21.9%, macro-algae increased 23.51% and the average sedimentation rate attained 77.52 mg cm-2d-1 with persisting coral reef diseases of 17.59%. The Pearson correlation showed that the coral cover decreased with increasing macro-algae growth, which was statistically significant ( r = -0.774, n = 100, P K. alvarezii, P. gymnosphora and C. lentillifera increased with percentages of 6.0, 5.8, 5.7, 4.9, 4.2, 3.7, 2.7 and 1.9, respectively. If this trend continues, the next generation of new recruit corals will undoubtedly lead to a phase shift in Gulf of Mannar corals.

Turning up the heat: increasing temperature and coral bleaching at the high latitude coral reefs of the Houtman Abrolhos Islands.

Science.gov (United States)

Abdo, David A; Bellchambers, Lynda M; Evans, Scott N

2012-01-01

Coral reefs face increasing pressures particularly when on the edge of their distributions. The Houtman Abrolhos Islands (Abrolhos) are the southernmost coral reef system in the Indian Ocean, and one of the highest latitude reefs in the world. These reefs have a unique mix of tropical and temperate marine fauna and flora and support 184 species of coral, dominated by Acropora species. A significant La Niña event during 2011 produced anomalous conditions of increased temperature along the whole Western Australian coastline, producing the first-recorded widespread bleaching of corals at the Abrolhos. We examined long term trends in the marine climate at the Abrolhos using historical sea surface temperature data (HadISST data set) from 1900-2011. In addition in situ water temperature data for the Abrolhos (from data loggers installed in 2008, across four island groups) were used to determine temperature exposure profiles. Coupled with the results of coral cover surveys conducted annually since 2007; we calculated bleaching thresholds for monitoring sites across the four Abrolhos groups. In situ temperature data revealed maximum daily water temperatures reached 29.54°C in March 2011 which is 4.2°C above mean maximum daily temperatures (2008-2010). The level of bleaching varied across sites with an average of ∼12% of corals bleached. Mortality was high, with a mean ∼50% following the 2011 bleaching event. Prior to 2011, summer temperatures reached a mean (across all monitoring sites) of 25.1°C for 2.5 days. However, in 2011 temperatures reached a mean of 28.1°C for 3.3 days. Longer term trends (1900-2011) showed mean annual sea surface temperatures increase by 0.01°C per annum. Long-term temperature data along with short-term peaks in 2011, outline the potential for corals to be exposed to more frequent bleaching risk with consequences for this high latitude coral reef system at the edge of its distribution.

Is proximity to land-based sources of coral stressors an appropriate measure of risk to coral reefs? An example from the Florida Reef Tract.

Science.gov (United States)

Lirman, Diego; Fong, Peggy

2007-06-01

Localized declines in coral condition are commonly linked to land-based sources of stressors that influence gradients of water quality, and the distance to sources of stressors is commonly used as a proxy for predicting the vulnerability and future status of reef resources. In this study, we evaluated explicitly whether proximity to shore and connections to coastal bays, two measures of potential land-based sources of disturbance, influence coral community and population structure, and the abundance, distribution, and condition of corals within patch reefs of the Florida Reef Tract. In the Florida Keys, long-term monitoring has documented significant differences in water quality along a cross-shelf gradient. Inshore habitats exhibit higher levels of nutrients (DIN and TP), TOC, turbidity, and light attenuation, and these levels decrease with increasing distance from shore and connections to tidal bays. In clear contrast to these patterns of water quality, corals on inshore patch reefs exhibited significantly higher coral cover, higher growth rates, and lower partial mortality rates than those documented in similar offshore habitats. Coral recruitment rates did not differ between inshore and offshore habitats. Corals on patch reefs closest to shore had well-spread population structures numerically dominated by intermediate to large colonies, while offshore populations showed narrower size-distributions that become increasingly positively skewed. Differences in size-structure of coral populations were attributed to faster growth and lower rates of partial mortality at inshore habitats. While the underlying causes for the favorable condition of inshore coral communities are not yet known, we hypothesize that the ability of corals to shift their trophic mode under adverse environmental conditions may be partly responsible for the observed patterns, as shown in other reef systems. This study, based on data collected from a uniform reef habitat type and coral species

Nitrogen cycling in corals: the key to understanding holobiont functioning?

KAUST Repository

Rädecker, Nils

2015-04-01

Corals are animals that form close mutualistic associations with endosymbiotic photosynthetic algae of the genus Symbiodinium. Together they provide the calcium carbonate framework of coral reef ecosystems. The importance of the microbiome (i.e., bacteria, archaea, fungi, and viruses) to holobiont functioning has only recently been recognized. Given that growth and density of Symbiodinium within the coral host is highly dependent on nitrogen availability, nitrogen-cycling microbes may be of fundamental importance to the stability of the coral–algae symbiosis and holobiont functioning, in particular under nutrient-enriched and -depleted scenarios. We summarize what is known about nitrogen cycling in corals and conclude that disturbance of microbial nitrogen cycling may be tightly linked to coral bleaching and disease.

Nitrogen cycling in corals: the key to understanding holobiont functioning?

KAUST Repository

Rä decker, Nils; Pogoreutz, Claudia; Voolstra, Christian R.; Wiedenmann, Jö rg; Wild, Christian

2015-01-01

Corals are animals that form close mutualistic associations with endosymbiotic photosynthetic algae of the genus Symbiodinium. Together they provide the calcium carbonate framework of coral reef ecosystems. The importance of the microbiome (i.e., bacteria, archaea, fungi, and viruses) to holobiont functioning has only recently been recognized. Given that growth and density of Symbiodinium within the coral host is highly dependent on nitrogen availability, nitrogen-cycling microbes may be of fundamental importance to the stability of the coral–algae symbiosis and holobiont functioning, in particular under nutrient-enriched and -depleted scenarios. We summarize what is known about nitrogen cycling in corals and conclude that disturbance of microbial nitrogen cycling may be tightly linked to coral bleaching and disease.

Emerging coral diseases in Kāne'ohe Bay, O'ahu, Hawai'i (USA): two major disease outbreaks of acute Montipora white syndrome.

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Aeby, Greta S; Callahan, Sean; Cox, Evelyn F; Runyon, Christina; Smith, Ashley; Stanton, Frank G; Ushijima, Blake; Work, Thierry M

2016-05-26

In March 2010 and January 2012, we documented 2 widespread and severe coral disease outbreaks on reefs throughout Kāne'ohe Bay, Hawai'i (USA). The disease, acute Montipora white syndrome (aMWS), manifested as acute and progressive tissue loss on the common reef coral M. capitata. Rapid visual surveys in 2010 revealed 338 aMWS-affected M. capitata colonies with a disease abundance of (mean ± SE) 0.02 ± 0.01 affected colonies per m of reef surveyed. In 2012, disease abundance was significantly higher (1232 aMWS-affected colonies) with 0.06 ± 0.02 affected colonies m(-1). Prior surveys found few acute tissue loss lesions in M. capitata in Ka¯ne'ohe Bay; thus, the high number of infected colonies found during these outbreaks would classify this as an emerging disease. Disease abundance was highest in the semi-enclosed region of south Kāne'ohe Bay, which has a history of nutrient and sediment impacts from terrestrial runoff and stream discharge. In 2010, tagged colonies showed an average tissue loss of 24% after 1 mo, and 92% of the colonies continued to lose tissue in the subsequent month but at a slower rate (chronic tissue loss). The host-specific nature of this disease (affecting only M. capitata) and the apparent spread of lesions between M. capitata colonies in the field suggest a potential transmissible agent. The synchronous appearance of affected colonies on multiple reefs across Kāne'ohe Bay suggests a common underlying factor. Both outbreaks occurred during the colder, rainy winter months, and thus it is likely that some parameter(s) associated with winter environmental conditions are linked to the emergence of disease outbreaks on these reefs.

Agents of coral mortality on reef formations of the Colombian Pacific

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Raúl Navas-Camacho

2010-05-01

Full Text Available The National Monitoring System for Coral Reefs of Colombia (SIMAC monitors the impact of some of the most important agents of coral tissue loss (bleaching and/or disease in the Colombian Pacific coral formations since 1998. Physiological bleaching is among the main results of stress in the area. Signs of coral diseases resembling bacterial bleaching such as White Plague and White Band, were observed in Malpelo and Gorgona islands. Damage to the Pacific gorgonian Pacifigorgia spp., similar to those produced by Aspergillosis in Caribbean corals, was detected in Utría Bay. The presence of tumors in colonies of massive corals was also recorded. Even though coral diseases are globally widespread, their occurrence in American Pacific reefs has been poorly documented to date. Rev. Biol. Trop. 58 (Suppl. 1: 133-138. Epub 2010 May 01.A través del Sistema Nacional de Monitoreo de Arrecifes Coralinos en Colombia-SIMAC se han evaluado algunos agentes de mortalidad coralina en el Pacifico Colombiano desde 1998. Uno de los principales factores que han contribuido a la pérdida de cobertura coralina han sido los eventos de blanqueamiento. No obstante, también se han observado signos que sugieren la presencia de enfermedades coralinas como el blanqueamiento bacteriano, la Plaga Blanca, la Banda Blanca, los tumores coralinos y la Aspergilosis en Pacifigorgia spp.. Aunque las enfermedades coralinas están globalmente distribuidas, su ocurrencia en el Pacifico tropical americano ha sido pobremente documentada. Esta nota incluye la ocurrencia de potenciales enfermedades coralinas en el Pacífico Colombiano.

Towards a new paleotemperature proxy from reef coral occurrences.

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Lauchstedt, Andreas; Pandolfi, John M; Kiessling, Wolfgang

2017-09-05

Global mean temperature is thought to have exceeded that of today during the last interglacial episode (LIG, ~ 125,000 yrs b.p.) but robust paleoclimate data are still rare in low latitudes. Occurrence data of tropical reef corals may provide new proxies of low latitude sea-surface temperatures. Using modern reef coral distributions we developed a geographically explicit model of sea surface temperatures. Applying this model to coral occurrence data of the LIG provides a latitudinal U-shaped pattern of temperature anomalies with cooler than modern temperatures around the equator and warmer subtropical climes. Our results agree with previously published estimates of LIG temperatures and suggest a poleward broadening of the habitable zone for reef corals during the LIG.

Behaviourally mediated phenotypic selection in a disturbed coral reef environment.

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Mark I McCormick

2009-09-01

Full Text Available Natural and anthropogenic disturbances are leading to changes in the nature of many habitats globally, and the magnitude and frequency of these perturbations are predicted to increase under climate change. Globally coral reefs are one of the most vulnerable ecosystems to climate change. Fishes often show relatively rapid declines in abundance when corals become stressed and die, but the processes responsible are largely unknown. This study explored the mechanism by which coral bleaching may influence the levels and selective nature of mortality on a juvenile damselfish, Pomacentrus amboinensis, which associates with hard coral. Recently settled fish had a low propensity to migrate small distances (40 cm between habitat patches, even when densities were elevated to their natural maximum. Intraspecific interactions and space use differ among three habitats: live hard coral, bleached coral and dead algal-covered coral. Large fish pushed smaller fish further from the shelter of bleached and dead coral thereby exposing smaller fish to higher mortality than experienced on healthy coral. Small recruits suffered higher mortality than large recruits on bleached and dead coral. Mortality was not size selective on live coral. Survival was 3 times as high on live coral as on either bleached or dead coral. Subtle behavioural interactions between fish and their habitats influence the fundamental link between life history stages, the distribution of phenotypic traits in the local population and potentially the evolution of life history strategies.

Vibrio harveyi as a causative agent of the White Syndrome in tropical stony corals.

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Luna, Gian Marco; Bongiorni, Lucia; Gili, Claudia; Biavasco, Francesca; Danovaro, Roberto

2010-02-01

We investigated bacterial assemblages associated with corals displaying symptoms of the 'White Syndrome' (WS), a general term used for indicating the appearance of bands, spots or patches of tissue loss, which is devastating wide areas of tropical ecosystems worldwide. We collected WS-diseased (n = 15) and healthy (n = 15) corals from the natural reef (Indonesia, Indian Ocean) and from four large public aquaria. By using culture-dependent and culture-independent techniques, we found that a large fraction (73%) of the investigated WS events was associated with the presence of a high bacterial abundance and, specifically, of Vibrio spp. Vibrio harveyi, a pathogen of many marine organisms and recently involved in coral Yellow Band disease, was the most represented species, being recovered from five out of 15 diseased corals. In experimental infection assays, two V. harveyi strains, isolated from diseased corals, were inoculated on a total of 62 healthy colonies of Pocillopora damicornis. WS signs appeared in 57 corals, confirming the ability of V. harveyi strains to induce the disease. We conclude that V. harveyi is one of the coral pathogens involved in the appearance of WS. However, not all of the investigated WSs were associated to V. harveyi detection, nor to other Vibrio species (such as V. coralliilyticus), which supports the hypothesis that WS is not caused exclusively by Vibrio spp., but rather can have a multifactorial aetiology, or can represent a group of diseases caused by a variety of agents. Further investigations to identify specific virulence traits will contribute to the understanding of the role of V. harveyi in WS pathogenesis. © 2009 Society for Applied Microbiology and Blackwell Publishing Ltd.

Early-phase dynamics in coral recovery following cyclone disturbance on the inshore Great Barrier Reef, Australia

Science.gov (United States)

Sato, Yui; Bell, Sara C.; Nichols, Cassandra; Fry, Kent; Menéndez, Patricia; Bourne, David G.

2018-06-01

Coral recovery (the restoration of abundance and composition of coral communities) after disturbance is a key process that determines the resilience of reef ecosystems. To understand the mechanisms underlying the recovery process of coral communities, colony abundance and size distribution were followed on reefs around Pelorus Island, located in the inshore central region of the Great Barrier Reef, following a severe tropical cyclone in 2011 that caused dramatic loss of coral communities. Permanent quadrats (600 m2) were monitored biannually between 2012 and 2016, and individual coral colonies were counted, sized and categorized into morphological types. The abundance of coral recruits and coral cover were also examined using permanent quadrats and random line intercept transects, respectively. The number of colonies in the smallest size class (4-10 cm) increased substantially during the study period, driving the recovery of coral populations. The total number of coral colonies 5 yr post-cyclone reached between 73 and 122% of pre-cyclone levels though coral cover remained between 16 and 31% of pre-cyclone levels, due to the dominance of small coral colonies in the recovering communities. Temporal transitions of coral demography (i.e., colony-size distributions) illustrated that the number of recently established coral populations overtook communities of surviving colonies. Coral recruits (coral recovery. A shift in morphological composition of coral communities was also observed, with the relative abundance of encrusting corals reduced post-cyclone in contrast to their dominance prior to the disturbance. This study identifies the fine-scale processes involved in the initial recovery of coral reefs, providing insights into the dynamics of coral demography that are essential for determining coral reef resilience following major disturbance.

The role of coral colony health state in the recovery of lesions

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Claudia P. Ruiz-Diaz

2016-01-01

Full Text Available Coral disease literature has focused, for the most part, on the etiology of the more than 35 coral afflictions currently described. Much less understood are the factors that underpin the capacity of corals to regenerate lesions, including the role of colony health. This lack of knowledge with respect to the factors that influence tissue regeneration significantly limits our understanding of the impact of diseases at the colony, population, and community level. In this study, we experimentally compared tissue regeneration capacity of diseased versus healthy fragments of Gorgonia ventalina colonies at 5 m and 12 m of depth. We found that the initial health state of colonies (i.e., diseased or healthy had a significant effect on tissue regeneration (healing. All healthy fragments exhibited full recovery regardless of depth treatment, while diseased fragments did not. Our results suggest that being diseased or healthy has a significant effect on the capacity of a sea fan colony to repair tissue, but that environmental factors associated with changes in depth, such as temperature and light, do not. We conclude that disease doesn’t just compromise vital functions such as growth and reproduction in corals but also compromises their capacity to regenerate tissue and heal lesions.

White syndrome on massive corals: A case study in Paiton power plant, East Java

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Muzaki, Farid Kamal; Saptarini, Dian; Riznawati, Aida Efrini

2017-06-01

As a stenothermal organism, coral easily affected by high-temperature cooling water discharged by a power plant into surrounding waters; which may lead to a rapid spread and transmission of coral disease, including White Syndrome. This study aimed to measure the prevalence of WS on massive corals in Paiton Power Plant waters. Research was conductedduring May 2015 at three observation stations; west and east side of water discharge canal (DB and DT) and water intake canal (WI). Observed parameters including ambient environmental variables (sea surface and bottom temperature, salinity, dissolved oxygen/DO, pH, and visibility); the cover of life corals (percent and genera composition) and prevalence of coral disease at 5 m depth. One-way ANOVA (analysis of variance, p=0.05) was performed to test the difference of coral disease prevalence from different observation stations. As the results, Coral coverage percentage in WI (85.75%), DB (60.75%), and DT (40.8%). Prevalence of WS in DB was highest (40.49±2.12% in DB, 13.53±11.5% in DT and 6.44±3.6 %, respectively). It can be assumed that prevalence of White Syndrome in those locations may be correlated to temperature which highest average temperature occurred in DB stations.

Microbial consortia of gorgonian corals from the Aleutian islands.

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Gray, Michael A; Stone, Robert P; McLaughlin, Molly R; Kellogg, Christina A

2011-04-01

Gorgonians make up the majority of corals in the Aleutian archipelago and provide critical fish habitat in areas of economically important fisheries. The microbial ecology of the deep-sea gorgonian corals Paragorgea arborea, Plumarella superba, and Cryogorgia koolsae was examined with culture-based and 16S rRNA gene-based techniques. Six coral colonies (two per species) were collected. Samples from all corals were cultured, and clone libraries were constructed from P. superba and C. koolsae. Cultured bacteria were dominated by the Gammaproteobacteria, especially Vibrionaceae, with other phyla comprising libraries showed dramatically different bacterial communities between corals of the same species collected at different sites, with no clear pattern of conserved bacterial consortia. Two of the clone libraries (one from each coral species) were dominated by Tenericutes, with Alphaproteobacteria dominating the remaining sequences. The other libraries were more diverse and had a more even distribution of bacterial phyla, showing more similarity between genera than within coral species. Here we report the first microbiological characterization of P. arborea, P. superba, and C. koolsae. FEMS Microbiology Ecology © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. No claim to original US government works.

Benthic habitat characterization and distribution from two representative sites of the deep-water SML Coral Province (Mediterranean)

Science.gov (United States)

Vertino, A.; Savini, A.; Rosso, A.; Di Geronimo, I.; Mastrototaro, F.; Sanfilippo, R.; Gay, G.; Etiope, G.

2010-03-01

Two sites (MS04 and MS06) from the Santa Maria di Leuca (SML) Coral Province were analyzed by a video and acoustic survey during the National Italian Project Apulian Plateau Bank Ecosystem Study (APLABES). Site MS04 (Atlantis Mound) is characterized by a sub-conical mound, 500 m wide and 25 m high, located at a water depth of about 650 m. Site MS06 (Yellow Chain) comprises several elongated reliefs (NNW-SSE-oriented), up to 25 m high and 500 m in maximum lateral extent, located at a depth of between 490 and 540 m. At both sites, two main mesohabitats (mound and intermound) containing several coral-bearing and -barren macrohabitats were observed in recorded videos and detected in side-scan sonographs. The coral-rich macrohabitats, characterized by densely packed colonies of the scleractinians Madrepora oculata and, secondarily, Lophelia pertusa ( M/ L), are typically restricted to the mound areas. The mud-dominated ones, almost devoid of M/L colonies, are more common within the intermound mesohabitat. However, on the most extensive mounds, both macrohabitat typologies exist. They are heterogeneously distributed on the mound surface, often showing a clear differentiation along two opposite flanks of the same topographic feature. M/ L-rich macrohabitats are preferentially located on top and along the mound northeastern flank, showing a typical step-like distribution, probably reflecting the arrangement of hard substrate outcrops. Along this flank, fan-shaped Madrepora colonies and sponges are often oriented NNW-SSE, implying, together with other evidence, a primary southwestern current flow. The hard-bottom macrohabitats of the southwestern mound flank are generally restricted to sparse exposed, subvertical to overhanging scarps as well as to heterometric boulders located at the scarp base. Their fauna is mainly characterized by small-sized organisms (such as sponges and solitary scleractinians) although m-sized boulders may locally host very large antipatharian

Gulf of Mexico Deep-Sea Coral Ecosystem Studies, 2008-2011

Science.gov (United States)

Kellogg, Christina A.

2009-01-01

Most people are familiar with tropical coral reefs, located in warm, well-illuminated, shallow waters. However, corals also exist hundreds and even thousands of meters below the ocean surface, where it is cold and completely dark. These deep-sea corals, also known as cold-water corals, have become a topic of interest due to conservation concerns over the impacts of trawling, exploration for oil and gas, and climate change. Although the existence of these corals has been known since the 1800s, our understanding of their distribution, ecology, and biology is limited due to the technical difficulties of conducting deep-sea research. DISCOVRE (DIversity, Systematics, and COnnectivity of Vulnerable Reef Ecosystems) is a new U.S. Geological Survey (USGS) program focused on deep-water coral ecosystems in the Gulf of Mexico. This integrated, multidisciplinary, international effort investigates a variety of topics related to unique and fragile deep-sea coral ecosystems from the microscopic level to the ecosystem level, including components of microbiology, population genetics, paleoecology, food webs, taxonomy, community ecology, physical oceanography, and mapping.

Major similarities in the bacterial communities associated with lesioned and healthy Fungiidae corals

KAUST Repository

Apprill, Amy; Hughen, Konrad; Mincer, Tracy

2013-01-01

Cultivation-based studies have demonstrated that yellow-band disease (YBD), a lesion-producing ailment affecting diverse species of coral, is caused by a consortium of Vibrio spp. This study takes the first cultivation-independent approach to examine the whole bacterial community associated with YBD-like lesioned corals. Two species of Fungiidae corals, Ctenactis crassa and Herpolitha limax, displaying YBD-like lesions were examined across diverse reefs throughout the Red Sea. Using a pyrosequencing approach targeting the V1-V3 regions of the SSU rRNA gene, no major differences in bacterial community composition or diversity were identified between healthy and lesioned corals of either species. Indicator species analysis did not find Vibrio significantly associated with the lesioned corals. However, operational taxonomic units belonging to the Ruegeria genus of Alphaproteobacteria and NS9 marine group of Flavobacteria were significantly associated with the lesioned corals. The most striking trend of this dataset was that reef location was found to be the most significant influence on the coral-bacterial community. It is possible that more pronounced lesion-specific bacterial signatures might have been concealed by the strong influence of environmental conditions on coral-bacteria. Overall, this study demonstrates inconsistencies between cultivation-independent and cultivation-based studies regarding the role of specific bacteria in coral diseases. © 2013 John Wiley & Sons Ltd and Society for Applied Microbiology.

Major similarities in the bacterial communities associated with lesioned and healthy Fungiidae corals

KAUST Repository

Apprill, Amy

2013-03-21

Cultivation-based studies have demonstrated that yellow-band disease (YBD), a lesion-producing ailment affecting diverse species of coral, is caused by a consortium of Vibrio spp. This study takes the first cultivation-independent approach to examine the whole bacterial community associated with YBD-like lesioned corals. Two species of Fungiidae corals, Ctenactis crassa and Herpolitha limax, displaying YBD-like lesions were examined across diverse reefs throughout the Red Sea. Using a pyrosequencing approach targeting the V1-V3 regions of the SSU rRNA gene, no major differences in bacterial community composition or diversity were identified between healthy and lesioned corals of either species. Indicator species analysis did not find Vibrio significantly associated with the lesioned corals. However, operational taxonomic units belonging to the Ruegeria genus of Alphaproteobacteria and NS9 marine group of Flavobacteria were significantly associated with the lesioned corals. The most striking trend of this dataset was that reef location was found to be the most significant influence on the coral-bacterial community. It is possible that more pronounced lesion-specific bacterial signatures might have been concealed by the strong influence of environmental conditions on coral-bacteria. Overall, this study demonstrates inconsistencies between cultivation-independent and cultivation-based studies regarding the role of specific bacteria in coral diseases. © 2013 John Wiley & Sons Ltd and Society for Applied Microbiology.

Oceanic forcing of coral reefs.

Science.gov (United States)

Lowe, Ryan J; Falter, James L

2015-01-01

Although the oceans play a fundamental role in shaping the distribution and function of coral reefs worldwide, a modern understanding of the complex interactions between ocean and reef processes is still only emerging. These dynamics are especially challenging owing to both the broad range of spatial scales (less than a meter to hundreds of kilometers) and the complex physical and biological feedbacks involved. Here, we review recent advances in our understanding of these processes, ranging from the small-scale mechanics of flow around coral communities and their influence on nutrient exchange to larger, reef-scale patterns of wave- and tide-driven circulation and their effects on reef water quality and perceived rates of metabolism. We also examine regional-scale drivers of reefs such as coastal upwelling, internal waves, and extreme disturbances such as cyclones. Our goal is to show how a wide range of ocean-driven processes ultimately shape the growth and metabolism of coral reefs.

Predicting dredging-associated effects to coral reefs in Apra Harbor, Guam - Part 2: Potential coral effects.

Science.gov (United States)

Nelson, Deborah Shafer; McManus, John; Richmond, Robert H; King, David B; Gailani, Joe Z; Lackey, Tahirih C; Bryant, Duncan

2016-03-01

Coral reefs are in decline worldwide due to anthropogenic stressors including reductions in water and substratum quality. Dredging results in the mobilization of sediments, which can stress and kill corals via increasing turbidity, tissue damage and burial. The Particle Tracking Model (PTM) was applied to predict the potential impacts of dredging-associated sediment exposure on the coral reef ecosystems of Apra Harbor, Guam. The data were interpreted using maps of bathymetry and coral abundance and distribution in conjunction with impact parameters of suspended sediment concentration (turbidity) and sedimentation using defined coral response thresholds. The results are presented using a "stoplight" model of negligible or limited impacts to coral reefs (green), moderate stress from which some corals would be expected to recover while others would not (yellow) and severe stress resulting in mortality (red). The red conditions for sediment deposition rate and suspended sediment concentration (SSC) were defined as values exceeding 25 mg cm(-2) d(-1) over any 30 day window and >20 mg/l for any 18 days in any 90 day period over a column of water greater than 2 m, respectively. The yellow conditions were defined as values >10 mg cm(-2) d(-1) and <25 mg cm(-2) d(-1) over any 30 day period, and as 20% of 3 months' concentration exceeding 10 mg/l for the deposition and SSC, respectively. The model also incorporates the potential for cumulative effects on the assumption that even sub-lethal stress levels can ultimately lead to mortality in a multi-stressor system. This modeling approach can be applied by resource managers and regulatory agencies to support management decisions related to planning, site selection, damage reduction, and compensatory mitigation. Published by Elsevier Ltd.

Coral photobiology: new light on old views.

Science.gov (United States)

Iluz, David; Dubinsky, Zvy

2015-04-01

The relationship between reef-building corals and light-harvesting pigments of zooxanthellae (Symbiodinium sp.) has been acknowledged for decades. The photosynthetic activity of the algal endocellular symbionts may provide up to 90% of the energy needed for the coral holobiont. This relationship limits the bathymetric distribution of coral reefs to the upper 100 m of tropical shorelines. However, even corals growing under high light intensities have to supplement the photosynthates translocated from the algae by predation on nutrient-rich zooplankton. New information has revealed how the fate of carbon acquired through photosynthesis differs from that secured by predation, whose rates are controlled by light-induced tentacular extension. The Goreau paradigm of "light-enhanced calcification" is being reevaluated, based on evidence that blue light stimulates coral calcification independently from photosynthesis rates. Furthermore, under dim light, calcification rates were stoichiometrically uncoupled from photosynthesis. The rates of photosynthesis of the zooxanthellae exhibit a clear endogenous rhythmicity maintained by light patterns. This daily pattern is concomitant with a periodicity of all the antioxidant protective mechanisms that wax and wane to meet the concomitant fluctuation in oxygen evolution. The phases of the moon are involved in the triggering of coral reproduction and control the spectacular annual mass-spawning events taking place in several reefs. The intensity and directionality of the underwater light field affect the architecture of coral colonies, leading to an optimization of the exposure of the zooxanthellae to light. We present a summary of major gaps in our understanding of the relationship between light and corals as a roadmap for future research. Copyright © 2014 Elsevier GmbH. All rights reserved.

Global habitat suitability for framework-forming cold-water corals.

Directory of Open Access Journals (Sweden)

Andrew J Davies

Full Text Available Predictive habitat models are increasingly being used by conservationists, researchers and governmental bodies to identify vulnerable ecosystems and species' distributions in areas that have not been sampled. However, in the deep sea, several limitations have restricted the widespread utilisation of this approach. These range from issues with the accuracy of species presences, the lack of reliable absence data and the limited spatial resolution of environmental factors known or thought to control deep-sea species' distributions. To address these problems, global habitat suitability models have been generated for five species of framework-forming scleractinian corals by taking the best available data and using a novel approach to generate high resolution maps of seafloor conditions. High-resolution global bathymetry was used to resample gridded data from sources such as World Ocean Atlas to produce continuous 30-arc second (∼1 km(2 global grids for environmental, chemical and physical data of the world's oceans. The increased area and resolution of the environmental variables resulted in a greater number of coral presence records being incorporated into habitat models and higher accuracy of model predictions. The most important factors in determining cold-water coral habitat suitability were depth, temperature, aragonite saturation state and salinity. Model outputs indicated the majority of suitable coral habitat is likely to occur on the continental shelves and slopes of the Atlantic, South Pacific and Indian Oceans. The North Pacific has very little suitable scleractinian coral habitat. Numerous small scale features (i.e., seamounts, which have not been sampled or identified as having a high probability of supporting cold-water coral habitat were identified in all ocean basins. Field validation of newly identified areas is needed to determine the accuracy of model results, assess the utility of modelling efforts to identify vulnerable marine

Molluscan assemblages on coral reefs and associated hard substrata in the northern Red Sea

Science.gov (United States)

Zuschin, M.; Hohenegger, J.; Steininger, F.

2001-09-01

Information on spatial variability and distribution patterns of organisms in coral reef environments is necessary to evaluate the increasing anthropogenic disturbance of marine environments (Richmond 1993; Wilkinson 1993; Dayton 1994). Therefore different types of subtidal, reef-associated hard substrata (reef flats, reef slopes, coral carpets, coral patches, rock grounds), each with different coral associations, were investigated to determine the distribution pattern of molluscs and their life habits (feeding strategies and substrate relations). The molluscs were strongly dominated by taxa with distinct relations to corals, and five assemblages were differentiated. The Dendropoma maxima assemblage on reef flats is a discrete entity, strongly dominated by this encrusting and suspension-feeding gastropod. All other assemblages are arranged along a substrate gradient of changing coral associations and potential molluscan habitats. The Coralliophila neritoidea- Barbatia foliata assemblage depends on the presence of Porites and shows a dominance of gastropods feeding on corals and of bivalves associated with living corals. The Chamoidea- Cerithium spp. assemblage on rock grounds is strongly dominated by encrusting bivalves. The Drupella cornus-Pteriidae assemblage occurs on Millepora- Acropora reef slopes and is strongly dominated by bivalves associated with living corals. The Barbatia setigera- Ctenoides annulata assemblage includes a broad variety of taxa, molluscan life habits and bottom types, but occurs mainly on faviid carpets and is transitional among the other three assemblages. A predicted degradation of coral coverage to rock bottoms due to increasing eutrophication and physical damage in the study area (Riegl and Piller 2000) will result in a loss of coral-associated molluscs in favor of bivalve crevice dwellers in dead coral heads and of encrusters on dead hard substrata.

Biology of corals and coral reefs

Digital Repository Service at National Institute of Oceanography (India)

Rajkumar, R.; Parulekar, A.H.

on the systematic position is presented. The general structure is depicted with illustrations. Physiology part is updated to current knowledge on reproduction, nutrition and excretion of corals. The coral reefs section begins with status of world reefs...

Distribution of Coral Reef and Seagrass Ecosystems’s Inorganic Carbon in the Waters of Beras Basah Bontang, East Kalimantan

Directory of Open Access Journals (Sweden)

Irwan Ramadhan Ritonga

2013-06-01

Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 Inorganic carbon is closely related to the calcification process (CaCO3, which is the main constituent of coral reefs or microorganisms that exist in the oceans such as foraminifera and cocolitoporit. Inorganic carbon is also closely linked to the chemical processes that occur when carbon dioxide gas (CO2 dissolved in water. The research of inorganic carbon in the waters of Beras Basah was carried out in January, February and March 2012. The purpose of this study was to understand the distribution and concentration of total inorganic carbon (CT in coral reef and seagrass ecosystems as well as the correlation of Beras Basah. The results showed that the concentration of total inorganic carbon (CT in January average 1166.503 μmol/kgSW, February average 1115.599 μmol/kgSW, and then in March the average 987.443 μmol/kgSW. Distribution patterns of total inorganic carbon (CT is vectoral, where in January, the concentration of total inorganic carbon (CT was highest in the Southeast region, was in February in the South and Southeast, while in March shifted to North region of Beras Basah Island. The concentration difference is thought to be influenced by pH and the seasons, tides, biochemical processes, and biological activity. Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 Doi: 10.12777/ijse.5.1.1-5 [How to cite this article: Ritonga, I.R., Supriharyono, and Henderarto, B. (2013. Distribution of Coral Reef and Seagrass Ecosystems’s Inorganic Carbon in the Waters of Beras Basah Bontang, East Kalimantan. International Journal of Science and Engineering, 5(1,1-6. Doi: 10.12777/ijse.5.1.1-5]  Mesophotic coral depth acclimatization is a function of host-specific symbiont physiology

KAUST Repository

Ziegler, Maren

2015-02-06

Mesophotic coral ecosystems receive increasing attention owing to their potential as deep coral refuges in times of global environmental change. Here, the mechanisms of coral holobiont photoacclimatization over a 60 m depth gradient in the central Red Sea were examined for the four coral genera Porites, Leptoseris, Pachyseris, and Podabacia. General acclimatization strategies were common to all host-symbiont combinations, e.g., Symbiodinium cell densities and photoprotective (PP) to light-harvesting pigment ratios both significantly decreased with water depth. Porites harbored Symbiodinium type C15 over the whole 60 m depth range, while Pachyseris and Podabacia had limited vertical distributions and hosted mainly Symbiodinium type C1. Symbiodinium type C15 had generally higher xanthophyll de-epoxidation rates and lower maximum quantum yields than C1, and also exhibited a strong photoacclimatory signal over depth that relates to the large distribution range of Porites. Interestingly, the coral host had an effect on Symbiodinium pigment composition. When comparing Symbiodinium type C1 in Podabacia and Pachyseris, the ß-carotene chl a−1, the peridinin chl a−1, and diadinoxanthin chl a−1 ratios were significantly different between host species. Our data support a view that depth acclimatization of corals in the mesophotics is facilitated by Symbiodinium physiology, which in turn is host-specific.

Mesophotic coral depth acclimatization is a function of host-specific symbiont physiology

KAUST Repository

Ziegler, Maren; Roder, Cornelia; Bü chel, Claudia; Voolstra, Christian R.

2015-01-01

Mesophotic coral ecosystems receive increasing attention owing to their potential as deep coral refuges in times of global environmental change. Here, the mechanisms of coral holobiont photoacclimatization over a 60 m depth gradient in the central Red Sea were examined for the four coral genera Porites, Leptoseris, Pachyseris, and Podabacia. General acclimatization strategies were common to all host-symbiont combinations, e.g., Symbiodinium cell densities and photoprotective (PP) to light-harvesting pigment ratios both significantly decreased with water depth. Porites harbored Symbiodinium type C15 over the whole 60 m depth range, while Pachyseris and Podabacia had limited vertical distributions and hosted mainly Symbiodinium type C1. Symbiodinium type C15 had generally higher xanthophyll de-epoxidation rates and lower maximum quantum yields than C1, and also exhibited a strong photoacclimatory signal over depth that relates to the large distribution range of Porites. Interestingly, the coral host had an effect on Symbiodinium pigment composition. When comparing Symbiodinium type C1 in Podabacia and Pachyseris, the ß-carotene chl a−1, the peridinin chl a−1, and diadinoxanthin chl a−1 ratios were significantly different between host species. Our data support a view that depth acclimatization of corals in the mesophotics is facilitated by Symbiodinium physiology, which in turn is host-specific.

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

Science.gov (United States)

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.

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

KAUST Repository

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

2013-01-01

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. © 2012 Elsevier Ltd.

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

KAUST Repository

Roder, Cornelia

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. © 2012 Elsevier Ltd.

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

Energy Technology Data Exchange (ETDEWEB)

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.

Evaluation of Stony Coral Indicators for Coral Reef ...

Science.gov (United States)

Colonies of reef-building stony corals at 57 stations around St. Croix, U.S. Virgin Islands were characterized by species, size and percentage of living tissue. Taxonomic, biological and physical indicators of coral condition were derived from these measurements and assessed for their response to gradients of human disturbance. The purpose of the study was to identify indicators that could be used for regulatory assessments under authority of the Clean Water Act--this requires that indicators distinguish anthropogenic disturbances from natural variation. Stony coral indicators were tested for correlation with human disturbance across gradients located on three different sides of the island. At the most intensely disturbed location, five of eight primary indicators were highly correlated with distance from the source of disturbance: Coral taxa richness, average colony size, the coefficient of variation of colony size (an indicator of colony size heterogeneity), total topographic coral surface area, and live coral surface area. An additional set of exploratory indicators related to rarity, reproductive and spawning mode, and taxonomic identity were also screened for association with disturbance at the same location. For the other two locations, there were no significant changes in indicator values and therefore no discernible effects of human activity. Coral indicators demonstrated sufficient precision to detect levels of change that would be applicable in a regio

Spirochaetes dominate the microbial community associated with the red coral Corallium rubrum on a broad geographic scale

KAUST Repository

van de Water, Jeroen A. J. M.; Melkonian, Ré my; Junca, Howard; Voolstra, Christian R.; Reynaud, Sté phanie; Allemand, Denis; Ferrier-Pagè s, Christine

2016-01-01

Mass mortality events in populations of the iconic red coral Corallium rubrum have been related to seawater temperature anomalies that may have triggered microbial disease development. However, very little is known about the bacterial community associated with the red coral. We therefore aimed to provide insight into this species’ bacterial assemblages using Illumina MiSeq sequencing of 16S rRNA gene amplicons generated from samples collected at five locations distributed across the western Mediterranean Sea. Twelve bacterial species were found to be consistently associated with the red coral, forming a core microbiome that accounted for 94.6% of the overall bacterial community. This core microbiome was particularly dominated by bacteria of the orders Spirochaetales and Oceanospirillales, in particular the ME2 family. Bacteria belonging to these orders have been implicated in nutrient cycling, including nitrogen, carbon and sulfur. While Oceanospirillales are common symbionts of marine invertebrates, our results identify members of the Spirochaetales as other important dominant symbiotic bacterial associates within Anthozoans.

Spirochaetes dominate the microbial community associated with the red coral Corallium rubrum on a broad geographic scale

KAUST Repository

van de Water, Jeroen A. J. M.

2016-06-06

Mass mortality events in populations of the iconic red coral Corallium rubrum have been related to seawater temperature anomalies that may have triggered microbial disease development. However, very little is known about the bacterial community associated with the red coral. We therefore aimed to provide insight into this species’ bacterial assemblages using Illumina MiSeq sequencing of 16S rRNA gene amplicons generated from samples collected at five locations distributed across the western Mediterranean Sea. Twelve bacterial species were found to be consistently associated with the red coral, forming a core microbiome that accounted for 94.6% of the overall bacterial community. This core microbiome was particularly dominated by bacteria of the orders Spirochaetales and Oceanospirillales, in particular the ME2 family. Bacteria belonging to these orders have been implicated in nutrient cycling, including nitrogen, carbon and sulfur. While Oceanospirillales are common symbionts of marine invertebrates, our results identify members of the Spirochaetales as other important dominant symbiotic bacterial associates within Anthozoans.

Bacterial communities of two ubiquitous Great Barrier Reef corals reveals both site- and species-specificity of common bacterial associates.

Directory of Open Access Journals (Sweden)

E Charlotte E Kvennefors

Full Text Available BACKGROUND: Coral-associated bacteria are increasingly considered to be important in coral health, and altered bacterial community structures have been linked to both coral disease and bleaching. Despite this, assessments of bacterial communities on corals rarely apply sufficient replication to adequately describe the natural variability. Replicated data such as these are crucial in determining potential roles of bacteria on coral. METHODOLOGY/PRINCIPAL FINDINGS: Denaturing Gradient Gel Electrophoresis (DGGE of the V3 region of the 16S ribosomal DNA was used in a highly replicated approach to analyse bacterial communities on both healthy and diseased corals. Although site-specific variations in the bacterial communities of healthy corals were present, host species-specific bacterial associates within a distinct cluster of gamma-proteobacteria could be identified, which are potentially linked to coral health. Corals affected by "White Syndrome" (WS underwent pronounced changes in their bacterial communities in comparison to healthy colonies. However, the community structure and bacterial ribotypes identified in diseased corals did not support the previously suggested theory of a bacterial pathogen as the causative agent of the syndrome. CONCLUSIONS/SIGNIFICANCE: This is the first study to employ large numbers of replicated samples to assess the bacterial communities of healthy and diseased corals, and the first culture-independent assessment of bacterial communities on WS affected Acroporid corals on the GBR. Results indicate that a minimum of 6 replicate samples are required in order to draw inferences on species, spatial or health-related changes in community composition, as a set of clearly distinct bacterial community profiles exist in healthy corals. Coral bacterial communities may be both site and species specific. Furthermore, a cluster of gamma-proteobacterial ribotypes may represent a group of specific common coral and marine

Calcification process dynamics in coral primary polyps as observed using a calcein incubation method

Directory of Open Access Journals (Sweden)

Yoshikazu Ohno

2017-03-01

Full Text Available Calcification processes are largely unknown in scleractinian corals. In this study, live confocal imaging was used to elucidate the spatiotemporal dynamics of the calcification process in aposymbiotic primary polyps of the coral species Acropora digitifera. The fluorophore calcein was used as a calcium deposition marker and a visible indicator of extracellular fluid distribution at the tissue-skeleton interface (subcalicoblastic medium, SCM in primary polyp tissues. Under continuous incubation in calcein-containing seawater, initial crystallization and skeletal growth were visualized among the calicoblastic cells in live primary polyp tissues. Additionally, the distribution of calcein-stained SCM and contraction movements of the pockets of SCM were captured at intervals of a few minutes. Our experimental system provided several new insights into coral calcification, particularly as a first step in monitoring the relationship between cellular dynamics and calcification in vivo. Our study suggests that coral calcification initiates at intercellular spaces, a finding that may contribute to the general understanding of coral calcification processes.

Bacteria associated with the coral Echinopora lamellosa (Esper ...

African Journals Online (AJOL)

USER

2007-12-10

Dec 10, 2007 ... with diseased corals in the Indian Ocean. However ... Indian Ocean, mucus samples were collected from healthy and apparently diseased Echinopora ..... The rising tide of ocean diseases: unsolved problems and research priorities. Front. Ecol. Environ. 2: 375-382. Harvell D, Jordan-Dahlgren E, Merkel S, ...

Forecasted coral reef decline in marine biodiversity hotspots under climate change.

Science.gov (United States)

Descombes, Patrice; Wisz, Mary S; Leprieur, Fabien; Parravicini, Valerianio; Heine, Christian; Olsen, Steffen M; Swingedouw, Didier; Kulbicki, Michel; Mouillot, David; Pellissier, Loïc

2015-01-21

Coral bleaching events threaten coral reef habitats globally and cause severe declines of local biodiversity and productivity. Related to high sea surface temperatures (SST), bleaching events are expected to increase as a consequence of future global warming. However, response to climate change is still uncertain as future low-latitude climatic conditions have no present-day analogue. Sea surface temperatures during the Eocene epoch were warmer than forecasted changes for the coming century, and distributions of corals during the Eocene may help to inform models forecasting the future of coral reefs. We coupled contemporary and Eocene coral occurrences with information on their respective climatic conditions to model the thermal niche of coral reefs and its potential response to projected climate change. We found that under the RCP8.5 climate change scenario, the global suitability for coral reefs may increase up to 16% by 2100, mostly due to improved suitability of higher latitudes. In contrast, in its current range, coral reef suitability may decrease up to 46% by 2100. Reduction in thermal suitability will be most severe in biodiversity hotspots, especially in the Indo-Australian Archipelago. Our results suggest that many contemporary hotspots for coral reefs, including those that have been refugia in the past, spatially mismatch with future suitable areas for coral reefs posing challenges to conservation actions under climate change. © 2015 John Wiley & Sons Ltd.

Loss of live coral compromises predator-avoidance behaviour in coral reef damselfish.

Science.gov (United States)

Boström-Einarsson, Lisa; Bonin, Mary C; Munday, Philip L; Jones, Geoffrey P

2018-05-17

Tropical reefs have experienced an unprecedented loss of live coral in the past few decades and the biodiversity of coral-dependent species is under threat. Many reef fish species decline in abundance as coral cover is lost, yet the mechanisms responsible for these losses are largely unknown. A commonly hypothesised cause of fish decline is the loss of shelter space between branches as dead corals become overgrown by algae. Here we tested this hypothesis by quantifying changes in predator-avoidance behaviour of a common damselfish, Pomacentrus moluccensis, before and after the death of their coral colony. Groups of P. moluccensis were placed on either healthy or degraded coral colonies, startled using a visual stimulus and their sheltering responses compared over a 7-week period. P. moluccensis stopped sheltering amongst the coral branches immediately following the death of the coral, despite the presence of ample shelter space. Instead, most individuals swam away from the dead coral, potentially increasing their exposure to predators. It appears that the presence of live coral rather than shelter per se is the necessary cue that elicits the appropriate behavioural response to potential predators. The disruption of this link poses an immediate threat to coral-associated fishes on degrading reefs.

CORAL Server and CORAL Server Proxy: Scalable Access to Relational Databases from CORAL Applications

CERN Document Server

Valassi, A; Kalkhof, A; Salnikov, A; Wache, M

2011-01-01

The CORAL software is widely used at CERN for accessing the data stored by the LHC experiments using relational database technologies. CORAL provides a C++ abstraction layer that supports data persistency for several backends and deployment models, including local access to SQLite files, direct client access to Oracle and MySQL servers, and read-only access to Oracle through the FroNTier web server and cache. Two new components have recently been added to CORAL to implement a model involving a middle tier "CORAL server" deployed close to the database and a tree of "CORAL server proxy" instances, with data caching and multiplexing functionalities, deployed close to the client. The new components are meant to provide advantages for read-only and read-write data access, in both offline and online use cases, in the areas of scalability and performance (multiplexing for several incoming connections, optional data caching) and security (authentication via proxy certificates). A first implementation of the two new c...

Sharing the slope: depth partitioning of agariciid corals and associated Symbiodinium across shallow and mesophotic habitats (2-60 m) on a Caribbean reef.

NARCIS (Netherlands)

Bongaerts, P.; Frade, P.R.; Ogier, J.J.; Hay, K.B.; van Bleijswijk, J.; Englebert, N.; Vermeij, M.J.A.; Bak, R.P.M.; Visser, P.M.; Hoegh-Guldberg, O

2013-01-01

Background Scleractinian corals and their algal endosymbionts (genus Symbiodinium) exhibit distinct bathymetric distributions on coral reefs. Yet, few studies have assessed the evolutionary context of these ecological distributions by exploring the genetic diversity of closely related coral species

Local Stressors, Resilience, and Shifting Baselines on Coral Reefs.

Science.gov (United States)

McLean, Matthew; Cuetos-Bueno, Javier; Nedlic, Osamu; Luckymiss, Marston; Houk, Peter

2016-01-01

Understanding how and why coral reefs have changed over the last twenty to thirty years is crucial for sustaining coral-reef resilience. We used a historical baseline from Kosrae, a typical small island in Micronesia, to examine changes in fish and coral assemblages since 1986. We found that natural gradients in the spatial distribution of fish and coral assemblages have become amplified, as island geography is now a stronger determinant of species abundance patterns, and habitat forming Acropora corals and large-bodied fishes that were once common on the leeward side of the island have become scarce. A proxy for fishing access best predicted the relative change in fish assemblage condition over time, and in turn, declining fish condition was the only factor correlated with declining coral condition, suggesting overfishing may have reduced ecosystem resilience. Additionally, a proxy for watershed pollution predicted modern coral assemblage condition, suggesting pollution is also reducing resilience in densely populated areas. Altogether, it appears that unsustainable fishing reduced ecosystem resilience, as fish composition has shifted to smaller species in lower trophic levels, driven by losses of large predators and herbivores. While prior literature and anecdotal reports indicate that major disturbance events have been rare in Kosrae, small localized disturbances coupled with reduced resilience may have slowly degraded reef condition through time. Improving coral-reef resilience in the face of climate change will therefore require improved understanding and management of growing artisanal fishing pressure and watershed pollution.

Local Stressors, Resilience, and Shifting Baselines on Coral Reefs.

Directory of Open Access Journals (Sweden)

Matthew McLean

Full Text Available Understanding how and why coral reefs have changed over the last twenty to thirty years is crucial for sustaining coral-reef resilience. We used a historical baseline from Kosrae, a typical small island in Micronesia, to examine changes in fish and coral assemblages since 1986. We found that natural gradients in the spatial distribution of fish and coral assemblages have become amplified, as island geography is now a stronger determinant of species abundance patterns, and habitat forming Acropora corals and large-bodied fishes that were once common on the leeward side of the island have become scarce. A proxy for fishing access best predicted the relative change in fish assemblage condition over time, and in turn, declining fish condition was the only factor correlated with declining coral condition, suggesting overfishing may have reduced ecosystem resilience. Additionally, a proxy for watershed pollution predicted modern coral assemblage condition, suggesting pollution is also reducing resilience in densely populated areas. Altogether, it appears that unsustainable fishing reduced ecosystem resilience, as fish composition has shifted to smaller species in lower trophic levels, driven by losses of large predators and herbivores. While prior literature and anecdotal reports indicate that major disturbance events have been rare in Kosrae, small localized disturbances coupled with reduced resilience may have slowly degraded reef condition through time. Improving coral-reef resilience in the face of climate change will therefore require improved understanding and management of growing artisanal fishing pressure and watershed pollution.

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

Science.gov (United States)

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.

Coral Reef Status of Navassa Island 2004

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Benthic and habitat data collected on the 2004 cruise to Navassa Islands National Wildlife Refuge. Parameters include benthic cover, coral disease prevalence,...

Turf algae-mediated coral damage in coastal reefs of Belize, Central America

KAUST Repository

Wild, Christian; Jantzen, Carin; Kremb, Stephan Georg

2014-01-01

Many coral reefs in the Caribbean experienced substantial changes in their benthic community composition during the last decades. This often resulted in phase shifts from scleractinian coral dominance to that by other benthic invertebrate or algae. However, knowledge about how the related role of coral-algae contacts may negatively affect corals is scarce. Therefore, benthic community composition, abundance of algae grazers, and the abundance and character of coral-algae contacts were assessed in situ at 13 Belizean reef sites distributed along a distance gradient to the Belizean mainland (12–70 km): Mesoamerican Barrier Reef (inshore), Turneffe Atoll (inner and outer midshore), and Lighthouse Reef (offshore). In situ surveys revealed significantly higher benthic cover by scleractinian corals at the remote Lighthouse Reef (26–29%) when compared to the other sites (4–19%). The abundance of herbivorous fish and the sea urchin Diadema antillarum significantly increased towards the offshore reef sites, while the occurrence of direct coral-algae contacts consequently increased significantly with decreasing distance to shore. About 60% of these algae contacts were harmful (exhibiting coral tissue damage, pigmentation change, or overgrowth) for corals (mainly genera Orbicella and Agaricia), particularly when filamentous turf algae were involved. These findings provide support to the hypothesis that (turf) algae-mediated coral damage occurs in Belizean coastal, near-shore coral reefs.

Turf algae-mediated coral damage in coastal reefs of Belize, Central America.

Science.gov (United States)

Wild, Christian; Jantzen, Carin; Kremb, Stephan Georg

2014-01-01

Many coral reefs in the Caribbean experienced substantial changes in their benthic community composition during the last decades. This often resulted in phase shifts from scleractinian coral dominance to that by other benthic invertebrate or algae. However, knowledge about how the related role of coral-algae contacts may negatively affect corals is scarce. Therefore, benthic community composition, abundance of algae grazers, and the abundance and character of coral-algae contacts were assessed in situ at 13 Belizean reef sites distributed along a distance gradient to the Belizean mainland (12-70 km): Mesoamerican Barrier Reef (inshore), Turneffe Atoll (inner and outer midshore), and Lighthouse Reef (offshore). In situ surveys revealed significantly higher benthic cover by scleractinian corals at the remote Lighthouse Reef (26-29%) when compared to the other sites (4-19%). The abundance of herbivorous fish and the sea urchin Diadema antillarum significantly increased towards the offshore reef sites, while the occurrence of direct coral-algae contacts consequently increased significantly with decreasing distance to shore. About 60% of these algae contacts were harmful (exhibiting coral tissue damage, pigmentation change, or overgrowth) for corals (mainly genera Orbicella and Agaricia), particularly when filamentous turf algae were involved. These findings provide support to the hypothesis that (turf) algae-mediated coral damage occurs in Belizean coastal, near-shore coral reefs.

Turf algae-mediated coral damage in coastal reefs of Belize, Central America

KAUST Repository

Wild, Christian

2014-09-16

Many coral reefs in the Caribbean experienced substantial changes in their benthic community composition during the last decades. This often resulted in phase shifts from scleractinian coral dominance to that by other benthic invertebrate or algae. However, knowledge about how the related role of coral-algae contacts may negatively affect corals is scarce. Therefore, benthic community composition, abundance of algae grazers, and the abundance and character of coral-algae contacts were assessed in situ at 13 Belizean reef sites distributed along a distance gradient to the Belizean mainland (12–70 km): Mesoamerican Barrier Reef (inshore), Turneffe Atoll (inner and outer midshore), and Lighthouse Reef (offshore). In situ surveys revealed significantly higher benthic cover by scleractinian corals at the remote Lighthouse Reef (26–29%) when compared to the other sites (4–19%). The abundance of herbivorous fish and the sea urchin Diadema antillarum significantly increased towards the offshore reef sites, while the occurrence of direct coral-algae contacts consequently increased significantly with decreasing distance to shore. About 60% of these algae contacts were harmful (exhibiting coral tissue damage, pigmentation change, or overgrowth) for corals (mainly genera Orbicella and Agaricia), particularly when filamentous turf algae were involved. These findings provide support to the hypothesis that (turf) algae-mediated coral damage occurs in Belizean coastal, near-shore coral reefs.

Uranium in coral skeletons determined by epithermal neutron activation analysis

International Nuclear Information System (INIS)

Ohde, S.; Hossain, M.M.M.; Ozaki, H.; Masuzawa, T.

2003-01-01

A simple and non-destructive method has been proposed for the routine determination of uranium by epithermal neutron activation analysis in coral skeletons. Using a cadmium capsule, about 0.1-0.2 g samples were irradiated for 6 hours in the Triga Mark II Reactor. Measurements of γ-ray ( 239 Np via 239 U) were performed with each sample and standard after cooling for about three days. Compared with a non-destructive thermal NAA, the present method was found to improve the sensitivity because it reduced the intense Compton background induced by 24 Na. Uranium in coral standards was determined within 2% of analytical precision. The data obtained for the carbonate standards are mostly consistent with reported values. The present method could be usefully applied to determine uranium contents in fossil corals from the Funafuti Atoll in the Pacific. The distribution of uranium between seawater and coral skeletons is also discussed in order to understand the environmental media in which the coral grew. (author)

The role of coral-associated bacterial communities in Australian Subtropical White Syndrome of Turbinaria mesenterina.

Science.gov (United States)

Godwin, Scott; Bent, Elizabeth; Borneman, James; Pereg, Lily

2012-01-01

Australian Subtropical White Syndrome (ASWS) is an infectious, temperature dependent disease of the subtropical coral Turbinaria mesenterina involving a hitherto unknown transmissible causative agent. This report describes significant changes in the coral associated bacterial community as the disease progresses from the apparently healthy tissue of ASWS affected coral colonies, to areas of the colony affected by ASWS lesions, to the dead coral skeleton exposed by ASWS. In an effort to better understand the potential roles of bacteria in the formation of disease lesions, the effect of antibacterials on the rate of lesion progression was tested, and both culture based and culture independent techniques were used to investigate the bacterial communities associated with colonies of T. mesenterina. Culture-independent analysis was performed using the Oligonucleotide Fingerprinting of Ribosomal Genes (OFRG) technique, which allowed a library of 8094 cloned bacterial 16S ribosomal genes to be analysed. Interestingly, the bacterial communities associated with both healthy and disease affected corals were very diverse and ASWS associated communities were not characterized by a single dominant organism. Treatment with antibacterials had a significant effect on the rate of progress of disease lesions (p = 0.006), suggesting that bacteria may play direct roles as the causative agents of ASWS. A number of potential aetiological agents of ASWS were identified in both the culture-based and culture-independent studies. In the culture-independent study an Alphaproteobacterium closely related to Roseovarius crassostreae, the apparent aetiological agent of juvenile oyster disease, was found to be significantly associated with disease lesions. In the culture-based study Vibrio harveyi was consistently associated with ASWS affected coral colonies and was not isolated from any healthy colonies. The differing results of the culture based and culture-independent studies highlight the

The role of coral-associated bacterial communities in Australian Subtropical White Syndrome of Turbinaria mesenterina.

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Scott Godwin

Full Text Available Australian Subtropical White Syndrome (ASWS is an infectious, temperature dependent disease of the subtropical coral Turbinaria mesenterina involving a hitherto unknown transmissible causative agent. This report describes significant changes in the coral associated bacterial community as the disease progresses from the apparently healthy tissue of ASWS affected coral colonies, to areas of the colony affected by ASWS lesions, to the dead coral skeleton exposed by ASWS. In an effort to better understand the potential roles of bacteria in the formation of disease lesions, the effect of antibacterials on the rate of lesion progression was tested, and both culture based and culture independent techniques were used to investigate the bacterial communities associated with colonies of T. mesenterina. Culture-independent analysis was performed using the Oligonucleotide Fingerprinting of Ribosomal Genes (OFRG technique, which allowed a library of 8094 cloned bacterial 16S ribosomal genes to be analysed. Interestingly, the bacterial communities associated with both healthy and disease affected corals were very diverse and ASWS associated communities were not characterized by a single dominant organism. Treatment with antibacterials had a significant effect on the rate of progress of disease lesions (p = 0.006, suggesting that bacteria may play direct roles as the causative agents of ASWS. A number of potential aetiological agents of ASWS were identified in both the culture-based and culture-independent studies. In the culture-independent study an Alphaproteobacterium closely related to Roseovarius crassostreae, the apparent aetiological agent of juvenile oyster disease, was found to be significantly associated with disease lesions. In the culture-based study Vibrio harveyi was consistently associated with ASWS affected coral colonies and was not isolated from any healthy colonies. The differing results of the culture based and culture-independent studies

Corals and Their Microbiomes Are Differentially Affected by Exposure to Elevated Nutrients and a Natural Thermal Anomaly

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Lu Wang

2018-03-01

Full Text Available Nutrient pollution can increase the prevalence and severity of coral disease and bleaching in ambient temperature conditions or during experimental thermal challenge. However, there have been few opportunities to study the effects of nutrient pollution during natural thermal anomalies. Here we present results from an experiment conducted during the 2014 bleaching event in the Florida Keys, USA, that exposed Agaricia sp. (Undaria and Siderastrea siderea corals to 3 types of elevated nutrients: nitrogen alone, phosphorous alone, and the combination of nitrogen and phosphorus. Overall, bleaching prevalence and severity was high regardless of treatment, but nitrogen enrichment alone both prolonged bleaching and increased coral mortality in Agaricia corals. At the same time, the elevated temperatures increased the prevalence of Dark Spot Syndrome (DSS, a disease typically associated with cold temperatures in Siderastrea siderea corals. However, nutrient exposure alone did not increase the prevalence or severity of disease, suggesting that thermal stress overwhelms the effects of nutrient pollution on this disease during such an extreme thermal event. Analysis of 78 Siderastrea siderea microbial metagenomes also showed that the thermal event was correlated with significant shifts in the composition and function of the associated microbiomes, and corals with DSS had microbiomes distinct from apparently healthy corals. In particular, we identified shifts in viral, archaeal, and fungal families. These shifts were likely driven by the extreme temperatures or other environmental co-variates occurring during the 2014 bleaching event. However, no microbial taxa were correlated with signs of DSS. Furthermore, although nutrient exposure did not affect microbial alpha diversity, it did significantly affect microbiome beta-diversity, an effect that was independent of time. These results suggest that strong thermal anomalies and local nutrient pollution both

Comparison of chemical compounds associated with sclerites from healthy and diseased sea fan corals (Gorgonia ventalina

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Carlos Toledo-Hernández

2017-08-01

Full Text Available Background The roles of gorgonian sclerites as structural components and predator deterrents have been widely studied. Yet their role as barriers against microbes has only recently been investigated, and even less is known about the diversity and roles of the chemical compounds associated with sclerites. Methods Here, we examine the semi-volatile organic compound fraction (SVOCs associated with sclerites from healthy and diseased Gorgonia ventalina sea fan corals to understand their possible role as a stress response or in defense of infection. We also measured the oxidative potential of compounds from diseased and healthy G. ventalina colonies. Results The results showed that sclerites harbor a great diversity of SVOCs. Overall, 70 compounds were identified, the majority of which are novel with unknown biological roles. The majority of SVOCs identified exhibit multiple immune-related roles including antimicrobial and radical scavenging functions. The free radical activity assays further confirmed the anti-oxidative potential of some these compounds. The anti-oxidative activity was, nonetheless, similar across sclerites regardless of the health condition of the colony, although sclerites from diseased sea fans display slightly higher anti-oxidative activity than the healthy ones. Discussion Sclerites harbor great SVOCs diversity, the majority of which are novel to sea fans or any other corals. Yet the scientific literature consulted showed that the roles of compounds found in sclerites vary from antioxidant to antimicrobial compounds. However, this study fell short in determine the origin of the SVOCs identified, undermining our capacity to determine the biological roles of the SVOCs on sclerites and sea fans.

Climate-driven coral reorganisation influences aggressive behaviour in juvenile coral-reef fishes

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Kok, Judith E.; Graham, Nicholas A. J.; Hoogenboom, Mia O.

2016-06-01

Globally, habitat degradation is altering the abundance and diversity of species in a variety of ecosystems. This study aimed to determine how habitat degradation, in terms of changing coral composition under climate change, affected abundance, species richness and aggressive behaviour of juveniles of three damselfishes ( Pomacentrus moluccensis, P. amboinensis and Dischistodus perspicillatus, in order of decreasing reliance on coral). Patch reefs were constructed to simulate two types of reefs: present-day reefs that are vulnerable to climate-induced coral bleaching, and reefs with more bleaching-robust coral taxa, thereby simulating the likely future of coral reefs under a warming climate. Fish communities were allowed to establish naturally on the reefs during the summer recruitment period. Climate-robust reefs had lower total species richness of coral-reef fishes than climate-vulnerable reefs, but total fish abundance was not significantly different between reef types (pooled across all species and life-history stages). The nature of aggressive interactions, measured as the number of aggressive chases, varied according to coral composition; on climate-robust reefs, juveniles used the substratum less often to avoid aggression from competitors, and interspecific aggression became relatively more frequent than intraspecific aggression for juveniles of the coral-obligate P. moluccensis. This study highlights the importance of coral composition as a determinant of behaviour and diversity of coral-reef fishes.

Impact of anthropogenic disturbances on the diversity of shallow stony corals in the Veracruz Reef System National Park Impacto de perturbaciones antrópicas sobre la diversidad de corales pétreos superficiales en el Parque Nacional Sistema Arrecifal veracruzano

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Carla V. Gutiérrez-Ruiz

2011-03-01

Full Text Available Anthropogenic disturbances may affect the development and maintenance of coral reefs by promoting diseases and other syndromes. In turn, this may cause local decreases in coral species diversity. In this study, we compared the prevalence of syndromes (including diseases and non-disease syndromes and the diversity of stony coral species between reefs located close (Sacrificios reef and far away (Santiaguillo reef of the port of Veracruz, Mexico. The prevalence of syndromes was higher at Sacrificios than at Santiaguillo, and it also increased with the abundance of coral colonies at the former reef. On the other hand, coral diversity was lower at Sacrificios than at Santiaguillo, suggesting that anthropogenic disturbances, besides promoting diseases and other syndromes, also lead to local decreases in species diversity.Las perturbaciones antropogénicas pueden afectar el desarrollo y mantenimiento de los arrecifes de coral mediante la promoción de las enfermedades y otros síndromes. A su vez, esto puede producir un descenso en la diversidad local de especies. En este estudio, se comparó la prevalencia de síndromes (tanto aquellos causados por enfermedades, como por otros factores y la diversidad de especies de corales pétreos entre arrecifes ubicados cerca (Sacrificios y lejos (Santiaguillo del puerto de Veracruz, México. La prevalencia de síndromes fue mayor en Sacrificios que en Santiaguillo, y también se incrementó con la abundancia de colonias de coral en Sacrificios. Por otra parte, la diversidad de corales fue menor en Sacrificios que en Santiaguillo, sugiriendo que las perturbaciones antropogénicas, además de promover las enfermedades y otros síndromes, también disminuyen localmente la diversidad de especies.

Metagenomic analysis indicates that stressors induce production of herpes-like viruses in the coral Porites compressa

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Vega Thurber, Rebecca L.; Barott, Katie L.; Hall, Dana; Liu, Hong; Rodriguez-Mueller, Beltran; Desnues, Christelle; Edwards, Robert A.; Haynes, Matthew; Angly, Florent E.; Wegley, Linda; Rohwer, Forest L.

2008-01-01

During the last several decades corals have been in decline and at least one-third of all coral species are now threatened with extinction. Coral disease has been a major contributor to this threat, but little is known about the responsible pathogens. To date most research has focused on bacterial and fungal diseases; however, viruses may also be important for coral health. Using a combination of empirical viral metagenomics and real-time PCR, we show that Porites compressa corals contain a suite of eukaryotic viruses, many related to the Herpesviridae. This coral-associated viral consortium was found to shift in response to abiotic stressors. In particular, when exposed to reduced pH, elevated nutrients, and thermal stress, the abundance of herpes-like viral sequences rapidly increased in 2 separate experiments. Herpes-like viral sequences were rarely detected in apparently healthy corals, but were abundant in a majority of stressed samples. In addition, surveys of the Nematostella and Hydra genomic projects demonstrate that even distantly related Cnidarians contain numerous herpes-like viral genes, likely as a result of latent or endogenous viral infection. These data support the hypotheses that corals experience viral infections, which are exacerbated by stress, and that herpes-like viruses are common in Cnidarians. PMID:19017800

A coral-on-a-chip microfluidic platform enabling live-imaging microscopy of reef-building corals

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Shapiro, Orr H.; Kramarsky-Winter, Esti; Gavish, Assaf R.; Stocker, Roman; Vardi, Assaf

2016-01-01

Coral reefs, and the unique ecosystems they support, are facing severe threats by human activities and climate change. Our understanding of these threats is hampered by the lack of robust approaches for studying the micro-scale interactions between corals and their environment. Here we present an experimental platform, coral-on-a-chip, combining micropropagation and microfluidics to allow direct microscopic study of live coral polyps. The small and transparent coral micropropagates are ideally suited for live-imaging microscopy, while the microfluidic platform facilitates long-term visualization under controlled environmental conditions. We demonstrate the usefulness of this approach by imaging coral micropropagates at previously unattainable spatio-temporal resolutions, providing new insights into several micro-scale processes including coral calcification, coral–pathogen interaction and the loss of algal symbionts (coral bleaching). Coral-on-a-chip thus provides a powerful method for studying coral physiology in vivo at the micro-scale, opening new vistas in coral biology. PMID:26940983

Mapping Coral Reef Resilience Indicators Using Field and Remotely Sensed Data

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Stuart Phinn

2013-03-01

Full Text Available In the face of increasing climate-related impacts on coral reefs, the integration of ecosystem resilience into marine conservation planning has become a priority. One strategy, including resilient areas in marine protected area (MPA networks, relies on information on the spatial distribution of resilience. We assess the ability to model and map six indicators of coral reef resilience—stress-tolerant coral taxa, coral generic diversity, fish herbivore biomass, fish herbivore functional group richness, density of juvenile corals and the cover of live coral and crustose coralline algae. We use high spatial resolution satellite data to derive environmental predictors and use these in random forest models, with field observations, to predict resilience indicator values at unsampled locations. Predictions are compared with those obtained from universal kriging and from a baseline model. Prediction errors are estimated using cross-validation, and the ability to map each resilience indicator is quantified as the percentage reduction in prediction error compared to the baseline model. Results are most promising (percentage reduction = 18.3% for mapping the cover of live coral and crustose coralline algae and least promising (percentage reduction = 0% for coral diversity. Our study has demonstrated one approach to map indicators of coral reef resilience. In the context of MPA network planning, the potential to consider reef resilience in addition to habitat and feature representation in decision-support software now exists, allowing planners to integrate aspects of reef resilience in MPA network development.

Photography of Coral Reefs from ISS

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Robinson, Julie A.

2009-01-01

This viewgraph presentation reviews the uses of photography from the International Space Station (ISS) in studying Earth's coral reefs. The photographs include reefs in various oceans . The photographs have uses for science in assisting NASA mapping initiatives, distribution worldwide through ReefBase, and by biologist in the field.

Coral Reef Watch, Degree Heating Weeks, 50 km

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National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Coral Reef Watch distributes Degree Heating Week products using a combination of the POES AVHRR Global Area Coverage data, and data from a climatological...

Overfishing and nutrient pollution interact with temperature to disrupt coral reefs down to microbial scales.

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Zaneveld, Jesse R; Burkepile, Deron E; Shantz, Andrew A; Pritchard, Catharine E; McMinds, Ryan; Payet, Jérôme P; Welsh, Rory; Correa, Adrienne M S; Lemoine, Nathan P; Rosales, Stephanie; Fuchs, Corinne; Maynard, Jeffrey A; Thurber, Rebecca Vega

2016-06-07

Losses of corals worldwide emphasize the need to understand what drives reef decline. Stressors such as overfishing and nutrient pollution may reduce resilience of coral reefs by increasing coral-algal competition and reducing coral recruitment, growth and survivorship. Such effects may themselves develop via several mechanisms, including disruption of coral microbiomes. Here we report the results of a 3-year field experiment simulating overfishing and nutrient pollution. These stressors increase turf and macroalgal cover, destabilizing microbiomes, elevating putative pathogen loads, increasing disease more than twofold and increasing mortality up to eightfold. Above-average temperatures exacerbate these effects, further disrupting microbiomes of unhealthy corals and concentrating 80% of mortality in the warmest seasons. Surprisingly, nutrients also increase bacterial opportunism and mortality in corals bitten by parrotfish, turning normal trophic interactions deadly for corals. Thus, overfishing and nutrient pollution impact reefs down to microbial scales, killing corals by sensitizing them to predation, above-average temperatures and bacterial opportunism.

Current status of coral reefs in the United Arab Emirates: Distribution, extent, and community structure with implications for management.

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Grizzle, Raymond E; Ward, Krystin M; AlShihi, Rashid M S; Burt, John A

2016-04-30

Coral reefs of the United Arab Emirates were once extensive, but have declined dramatically in recent decades. Marine management and policy have been hampered by outdated and inaccurate habitat maps and habitat quality information. We combined existing recent datasets with our newly mapped coral habitats to provide a current assessment of nation-wide extent, and performed quantitative surveys of communities at 23 sites to assess coral cover and composition. Over 132 km(2) of coral habitat was mapped, averaging 28.6 ± 3.8% live coral cover at surveyed sites. In the Arabian Gulf low cover, low richness Porites dominated communities characterized western Abu Dhabi, while reefs northeast of Abu Dhabi city generally contained higher richness and cover, and were dominated by merulinids (formerly faviids). Distinct communities occur in the Sea of Oman, where cover and richness were low. We provide management recommendations to enhance conservation of vulnerable coral reefs in the UAE. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

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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. © 2014 John Wiley & Sons Ltd.

Long distance dispersal and connectivity in amphi-Atlantic corals at regional and basin scales.

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Flavia L D Nunes

Full Text Available Among Atlantic scleractinian corals, species diversity is highest in the Caribbean, but low diversity and high endemism are observed in various peripheral populations in central and eastern Atlantic islands and along the coasts of Brazil and West Africa. The degree of connectivity between these distantly separated populations is of interest because it provides insight into processes at both evolutionary and ecological time scales, such as speciation, recruitment dynamics and the persistence of coral populations. To assess connectivity in broadly distributed coral species of the Atlantic, DNA sequence data from two nuclear markers were obtained for six coral species spanning their distributional ranges. At basin-wide scales, significant differentiation was generally observed among populations in the Caribbean, Brazil and West Africa. Concordance of patterns in connectivity among co-distributed taxa indicates that extrinsic barriers, such as the Amazon freshwater plume or long stretches of open ocean, restrict dispersal of coral larvae from region to region. Within regions, dispersal ability appears to be influenced by aspects of reproduction and life history. Two broadcasting species, Siderastrea siderea and Montastraea cavernosa, were able to maintain gene flow among populations separated by as much as 1,200 km along the coast of Brazil. In contrast, brooding species, such as Favia gravida and Siderastrea radians, had more restricted gene flow along the Brazilian coast.

Corals like it waxed: paraffin-based antifouling technology enhances coral spat survival.

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Jan Tebben

Full Text Available The early post-settlement stage is the most sensitive during the life history of reef building corals. However, few studies have examined the factors that influence coral mortality during this period. Here, the impact of fouling on the survival of newly settled coral spat of Acropora millepora was investigated by manipulating the extent of fouling cover on settlement tiles using non-toxic, wax antifouling coatings. Survival of spat on coated tiles was double that on control tiles. Moreover, there was a significant negative correlation between percentage cover of fouling and spat survival across all tiles types, suggesting that fouling in direct proximity to settled corals has detrimental effects on early post-settlement survival. While previous studies have shown that increased fouling negatively affects coral larval settlement and health of juvenile and adult corals, to the best of our knowledge, this is the first study to show a direct relationship between fouling and early post-settlement survival for a broadcast spawning scleractinian coral. The negative effects of fouling on this sensitive life history stage may become more pronounced in the future as coastal eutrophication increases. Our results further suggest that targeted seeding of coral spat on artificial surfaces in combination with fouling control could prove useful to improve the efficiency of sexual reproduction-based coral propagation for reef rehabilitation.

Extent of mangrove nursery habitats determines the geographic distribution of a coral reef fish in a South-Pacific archipelago.

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Christelle Paillon

Full Text Available Understanding the drivers of species' geographic distribution has fundamental implications for the management of biodiversity. For coral reef fishes, mangroves have long been recognized as important nursery habitats sustaining biodiversity in the Western Atlantic but there is still debate about their role in the Indo-Pacific. Here, we combined LA-ICP-MS otolith microchemistry, underwater visual censuses (UVC and mangrove cartography to estimate the importance of mangroves for the Indo-Pacific coral reef fish Lutjanus fulviflamma in the archipelago of New Caledonia. Otolith elemental compositions allowed high discrimination of mangroves and reefs with 83.8% and 98.7% correct classification, respectively. Reefs were characterized by higher concentrations of Rb and Sr and mangroves by higher concentrations of Ba, Cr, Mn and Sn. All adult L. fulviflamma collected on reefs presented a mangrove signature during their juvenile stage with 85% inhabiting mangrove for their entire juvenile life (about 1 year. The analysis of 2942 UVC revealed that the species was absent from isolated islands of the New Caledonian archipelago where mangroves were absent. Furthermore, strong positive correlations existed between the abundance of L. fulviflamma and the area of mangrove (r = 0.84 for occurrence, 0.93 for density and 0.89 for biomass. These results indicate that mangrove forest is an obligatory juvenile habitat for L. fulviflamma in New Caledonia and emphasize the potential importance of mangroves for Indo-Pacific coral reef fishes.

Echinoid associations with coral habitats differ with taxon in the deep sea and the influence of other echinoids, depth, and fishing history on their distribution

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Stevenson, Angela; Davies, Jaime S.; Williams, Alan; Althaus, Franziska; Rowden, Ashley A.; Bowden, David A.; Clark, Malcolm R.; Mitchell, Fraser J. G.

2018-03-01

Patterns of habitat use by animals and knowledge of the environmental factors affecting these spatial patterns are important for understanding the structure and dynamics of ecological communities. Both aspects are poorly known for deep-sea habitats. The present study investigates echinoid distributions within cold water coral (CWC) habitats on continental margins off France, Australia, and New Zealand. It further examines the influence of habitat-related variables that might help explain the observed distribution of echinoid taxa. Six echinoid taxa were examined from video and photographic transects to reveal taxon-specific distribution patterns and habitat-related influences. The Echinoidea were found in all habitats studied, but tended to aggregate in architecturally complex habitats associated with living cold-water corals. However, a taxon-specific investigation found that such associations were largely an artefact of the dominant taxa observed in a specific region. Despite the food and shelter resources offered to echinoids by matrix-forming coral habitats, not all taxa were associated with these habitats, and some had a random association with the habitats examined, while others displayed non-random associations. Echinoid distribution was correlated with several variables; the presence of other echinoids, depth, and fishing history were the most influential factors. This study indicates that image data can be a useful tool to detect trends in echinoid habitat associations. It also suggests that refinement of the methods, in particular with studies conducted at a more precise taxon and habitat scale, would facilitate better quantitative analyses of habitat associations and paint a more realistic picture of a population's ecology. Most deep-sea ecological studies to date have been conducted at a relatively coarse taxonomic and habitat resolution, and lack sufficient resolution to provide useful information for the conservation of vulnerable deep-sea habitats.

Evolutionary insights into scleractinian corals using comparative genomic hybridizations.

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Aranda, Manuel; DeSalvo, Michael K; Bayer, Till; Medina, Monica; Voolstra, Christian R

2012-09-21

Coral reefs belong to the most ecologically and economically important ecosystems on our planet. Yet, they are under steady decline worldwide due to rising sea surface temperatures, disease, and pollution. Understanding the molecular impact of these stressors on different coral species is imperative in order to predict how coral populations will respond to this continued disturbance. The use of molecular tools such as microarrays has provided deep insight into the molecular stress response of corals. Here, we have performed comparative genomic hybridizations (CGH) with different coral species to an Acropora palmata microarray platform containing 13,546 cDNA clones in order to identify potentially rapidly evolving genes and to determine the suitability of existing microarray platforms for use in gene expression studies (via heterologous hybridization). Our results showed that the current microarray platform for A. palmata is able to provide biological relevant information for a wide variety of coral species covering both the complex clade as well the robust clade. Analysis of the fraction of highly diverged genes showed a significantly higher amount of genes without annotation corroborating previous findings that point towards a higher rate of divergence for taxonomically restricted genes. Among the genes with annotation, we found many mitochondrial genes to be highly diverged in M. faveolata when compared to A. palmata, while the majority of nuclear encoded genes maintained an average divergence rate. The use of present microarray platforms for transcriptional analyses in different coral species will greatly enhance the understanding of the molecular basis of stress and health and highlight evolutionary differences between scleractinian coral species. On a genomic basis, we show that cDNA arrays can be used to identify patterns of divergence. Mitochondrion-encoded genes seem to have diverged faster than nuclear encoded genes in robust corals. Accordingly, this

Growth rate and age distribution of deep-sea black corals in the Gulf of Mexico

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Prouty, N.G.; Roark, E.B.; Buster, N.A.; Ross, Steve W.

2011-01-01

Black corals (order Antipatharia) are important long-lived, habitat-forming, sessile, benthic suspension feeders that are found in all oceans and are usually found in water depths greater than 30 m. Deep-water black corals are some of the slowest-growing, longest-lived deep-sea corals known. Previous age dating of a limited number of black coral samples in the Gulf of Mexico focused on extrapolated ages and growth rates based on skeletal 210Pb dating. Our results greatly expand the age and growth rate data of black corals from the Gulf of Mexico. Radiocarbon analysis of the oldest Leiopathes sp. specimen from the upper De Soto Slope at 300 m water depth indicates that these animals have been growing continuously for at least the last 2 millennia, with growth rates ranging from 8 to 22 µm yr–1. Visual growth ring counts based on scanning electron microscopy images were in good agreement with the 14C-derived ages, suggestive of annual ring formation. The presence of bomb-derived 14C in the outermost samples confirms sinking particulate organic matter as the dominant carbon source and suggests a link between the deep-sea and surface ocean. There was a high degree of reproducibility found between multiple discs cut from the base of each specimen, as well as within duplicate subsamples. Robust 14C-derived chronologies and known surface ocean 14C reservoir age constraints in the Gulf of Mexico provided reliable calendar ages with future application to the development of proxy records.

Coral lipids and environmental stress.

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Harriott, V J

1993-04-01

Environmental monitoring of coral reefs is presently limited by difficulties in recognising coral stress, other than by monitoring coral mortality over time. A recent report described an experiment demonstrating that a measured lipid index declined in shaded corals. The technique described might have application in monitoring coral health, with a decline in coral lipid index as an indicator of coral stress. The application of the technique as a practical monitoring tool was tested for two coral species from the Great Barrier Reef. Consistent with the previous results, lipid index for Pocillopora damicornis initially declined over a period of three weeks in corals maintained in filtered seawater in the dark, indicating possible utilization of lipid stored as energy reserves. However, lipid index subsequently rose to near normal levels. In contrast, lipid index of Acropora formosa increased after four weeks in the dark in filtered seawater. The results showed considerable variability in lipid content between samples from the same colony. Results were also found to be dependent on fixation times and sample weight, introducing potential error into the practical application of the technique. The method as described would be unsuitable for monitoring environmental stress in corals, but the search for a practical method to monitor coral health should continue, given its importance in coral reef management.

Occurrence of thraustochytrid fungi in corals and coral mucus

Digital Repository Service at National Institute of Oceanography (India)

Raghukumar, S.; Balasubramanian

Occurrence of thraustochytrid fungi in corals, fresh coral mucus and floating and attached mucus detritus from the Lakshadweep Islands in the Arabian Sea was studied. Corallochytrium limacisporum Raghukumar, Thraustochytrium motivum Goldstein...

African dust and the demise of Caribbean coral reefs

Science.gov (United States)

Shinn, E.A.; Smith, G.W.; Prospero, J.M.; Betzer, P.; Hayes, M.L.; Garrison, V.; Barber, R.T.

2000-01-01

The vitality of Caribbean coral reefs has undergone a continual state of decline since the late 1970s, a period of time coincidental with large increases in transatlantic dust transport. It is proposed that the hundreds of millions of tons/year of soil dust that have been crossing the Atlantic during the last 25 years could be a significant contributor to coral reef decline and may be affecting other ecosystems. Benchmark events, such as near synchronous Caribbean-wide mortalities of acroporid corals and the urchin Diadema in 1983, and coral bleaching beginning in 1987, correlate with the years of maximum dust flux into the Caribbean. Besides crustal elements, in particular Fe, Si, and aluminosilicate clays, the dust can serve as a substrate for numerous species of viable spores, especially the soil fungus Aspergillus. Aspergillus sydowii, the cause of an ongoing Caribbean-wide seafan disease, has been cultured from Caribbean air samples and used to inoculate sea fans.

Facilitation in Caribbean coral reefs: high densities of staghorn coral foster greater coral condition and reef fish composition.

Science.gov (United States)

Huntington, Brittany E; Miller, Margaret W; Pausch, Rachel; Richter, Lee

2017-05-01

Recovery of the threatened staghorn coral (Acropora cervicornis) is posited to play a key role in Caribbean reef resilience. At four Caribbean locations (including one restored and three extant populations), we quantified characteristics of contemporary staghorn coral across increasing conspecific densities, and investigated a hypothesis of facilitation between staghorn coral and reef fishes. High staghorn densities in the Dry Tortugas exhibited significantly less partial mortality, higher branch growth, and supported greater fish abundances compared to lower densities within the same population. In contrast, partial mortality, branch growth, and fish community composition did not vary with staghorn density at the three other study locations where staghorn densities were lower overall. This suggests that density-dependent effects between the coral and fish community may only manifest at high staghorn densities. We then evaluated one facilitative mechanism for such density-dependence, whereby abundant fishes sheltering in dense staghorn aggregations deliver nutrients back to the coral, fueling faster coral growth, thereby creating more fish habitat. Indeed, dense staghorn aggregations within the Dry Tortugas exhibited significantly higher growth rates, tissue nitrogen, and zooxanthellae densities than sparse aggregations. Similarly, higher tissue nitrogen was induced in a macroalgae bioassay outplanted into the same dense and sparse aggregations, confirming greater bioavailability of nutrients at high staghorn densities. Our findings inform staghorn restoration efforts, suggesting that the most effective targets may be higher coral densities than previously thought. These coral-dense aggregations may reap the benefits of positive facilitation between the staghorn and fish community, favoring the growth and survivorship of this threatened species.

The geochemistry of deep-sea coral skeletons: A review of vital effects and applications for palaeoceanography

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Robinson, Laura F.; Adkins, Jess F.; Frank, Norbert; Gagnon, Alexander C.; Prouty, Nancy G.; Brendan Roark, E.; de Flierdt, Tina van

2014-01-01

Deep-sea corals were discovered over a century ago, but it is only over recent years that focused efforts have been made to explore the history of the oceans using the geochemistry of their skeletal remains. They offer a promising archive of past oceanic environments given their global distribution, layered growth patterns, longevity and preservation as well as our ability to date them using radiometric techniques. This paper provides an overview of the current state-of-the-art in terms of geochemical approaches to using deep-sea coral skeletons to explore the history of the ocean. Deep-sea coral skeletons have a wide array of morphologies (e.g. solitary cup corals, branching colonial corals) and materials (calcite, aragonite and proteins). As such their biomineralization strategies are diverse, leading to complex geochemistry within coral skeletons. Notwithstanding these complications, progress has been made on developing methods for reconstructing the oceanographic environment in the past using trace elements and isotopic methods. Promising approaches within certain coral groups include clumped isotopes and Mg/Li for temperature reconstructions, boron isotopes and radiocarbon for carbon cycling, εNd, and radiocarbon for circulation studies and δ15N, P/Ca and Ba/Ca for nutrient tracer studies. Likewise there is now a range of techniques for dating deep-sea corals skeletons (e.g. U-series, radiocarbon), and determining their growth rates (e.g. radiocarbon and 210Pb). Dating studies on historic coral populations in the Atlantic, Southern Ocean and Pacific point to climate and environmental changes being dominant controls on coral populations over millennial and orbital timescales. This paper provides a review of a range of successes and promising approaches. It also highlights areas in which further research would likely provide new insights into biomineralization, palaeoceanography and distribution of past coral populations.

The northern limit of corals of the genus Acropora in temperate zones is determined by their resilience to cold bleaching.

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Higuchi, Tomihiko; Agostini, Sylvain; Casareto, Beatriz Estela; Suzuki, Yoshimi; Yuyama, Ikuko

2015-12-18

The distribution of corals in Japan covers a wide range of latitudes, encompassing tropical to temperate zones. However, coral communities in temperate zones contain only a small subset of species. Among the parameters that determine the distribution of corals, temperature plays an important role. We tested the resilience to cold stress of three coral species belonging to the genus Acropora in incubation experiments. Acropora pruinosa, which is the northernmost of the three species, bleached at 13 °C, but recovered once temperatures were increased. The two other species, A. hyacinthus and A. solitaryensis, which has a more southerly range than A. pruinosa, died rapidly after bleaching at 13 °C. The physiological effects of cold bleaching on the corals included decreased rates of photosynthesis, respiration, and calcification, similar to the physiological effects observed with bleaching due to high temperature stress. Contrasting hot bleaching, no increases in antioxidant enzyme activities were observed, suggesting that reactive oxygen species play a less important role in bleaching under cold stress. These results confirmed the importance of resilience to cold stress in determining the distribution and northern limits of coral species, as cold events causing coral bleaching and high mortality occur regularly in temperate zones.

Comparing deep-sea fish fauna between coral and non-coral "megahabitats" in the Santa Maria di Leuca cold-water coral province (Mediterranean Sea.

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Gianfranco D'Onghia

Full Text Available Two experimental longline surveys were carried out in the Santa Maria di Leuca (SML cold-water coral province (Mediterranean Sea during May-June and September-October 2010 to investigate the effect of corals on fish assemblages. Two types of "megahabitat" characterized by the virtual absence of fishing were explored. One was characterized by complex topography including mesohabitats with carbonate mounds and corals. The other type of megahabitat, although characterized by complex topographic features, lacks carbonate mounds and corals. The fishing vessel was equipped with a 3,000 m monofilament longline with 500 hooks and snoods of 2.5 m in length. A total of 9 hauls, using about 4,500 hooks, were carried out both in the coral megahabitat and in the non-coral megahabitat during each survey. The fish Leucoraja fullonica and Pteroplatytrygon violacea represent new records for the SML coral province. The coral by-catch was only obtained in the coral megahabitat in about 55% of the stations investigated in both surveys. The total catches and the abundance indices of several species were comparable between the two habitat typologies. The species contributing most to the dissimilarity between the two megahabitat fish assemblages were Pagellus bogaraveo, Galeus melastomus, Etmopterus spinax and Helicolenus dactylopterus for density and P. bogaraveo, Conger conger, Polyprion americanus and G. melastomus for biomass. P. bogaraveo was exclusively collected in the coral megahabitat, whereas C. conger, H. dactylopterus and P. americanus were found with greater abundance in the coral than in the non-coral megahabitat. Differences in the sizes between the two megahabitats were detected in E. spinax, G. melastomus, C. conger and H. dactylopterus. Although these differences most probably related to the presence-absence of corals, both megahabitats investigated play the role of attraction-refuge for deep-sea fish fauna, confirming the important role of the whole

Climate-change refugia: shading reef corals by turbidity.

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Cacciapaglia, Chris; van Woesik, Robert

2016-03-01

Coral reefs have recently experienced an unprecedented decline as the world's oceans continue to warm. Yet global climate models reveal a heterogeneously warming ocean, which has initiated a search for refuges, where corals may survive in the near future. We hypothesized that some turbid nearshore environments may act as climate-change refuges, shading corals from the harmful interaction between high sea-surface temperatures and high irradiance. We took a hierarchical Bayesian approach to determine the expected distribution of 12 coral species in the Indian and Pacific Oceans, between the latitudes 37°N and 37°S, under representative concentration pathway 8.5 (W m(-2) ) by 2100. The turbid nearshore refuges identified in this study were located between latitudes 20-30°N and 15-25°S, where there was a strong coupling between turbidity and tidal fluctuations. Our model predicts that turbidity will mitigate high temperature bleaching for 9% of shallow reef habitat (to 30 m depth) - habitat that was previously considered inhospitable under ocean warming. Our model also predicted that turbidity will protect some coral species more than others from climate-change-associated thermal stress. We also identified locations where consistently high turbidity will likely reduce irradiance to turbid nearshore refuges identified in this study, particularly in the northwestern Hawaiian Islands, the northern Philippines, the Ryukyu Islands (Japan), eastern Vietnam, western and eastern Australia, New Caledonia, the northern Red Sea, and the Arabian Gulf, should become part of a judicious global strategy for reef-coral persistence under climate change. © 2015 John Wiley & Sons Ltd.

Stochastic spatio-temporal model of coral cover as a function of herbivorous grazers, water quality, and coral demographics

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Neuhausler, R.; Robinson, M.; Bruna, M.

2017-12-01

Over the last 60 years we have seen an increased amount of ecological regime shifts in tropical coastal zones, from coral reefs to macroalgae dominated states, as a result of natural and anthropogenic stresses. However, these shifts are not always immediate- macroalgae are generally present in coral reefs, with their distribution regulated by herbivorous fish. This is especially true in Moorea, French Polynesia, where macroalgae are shown to flourish in spaces that provide refuge from roaming herbivores. While there are currently modeling efforts in projecting ecological regime shifts in Moorea, temporal deterministic models have been utilized, which fail to capture metastability between multiple steady states and can have issues when dealing with very small populations. To address these concerns, we build on these models to account for spatial variations and individual organisms, as well as stochasticity. Our model can project the percent cover of coral, macroalgae, and algae turf as a function of herbivorous grazers, water quality, and coral demographics. Grazers, included as individual fish (particles), evolve according to a kinetic model and interact with neighbouring benthic assemblages, represented as nodes. Water quality and coral demographics are input parameters that can vary over time, allowing our model to be run for temporally changing scenarios and to be adjusted for different reefs. We plan to engage with previous Moorea Reef Resilience Models through a comparative analysis of our models' outcomes and existing Moorea data. Coupling projective models with available data is useful for informing environmental policy and advancing the modeling field.

Fungi in Porites lutea: Association with healthy and diseased corals

Digital Repository Service at National Institute of Oceanography (India)

Ravindran, J.; Raghukumar, C.; Raghukumar, S.

It is found that fungi to occur regularly in healthy, partially dead, bleached and pink-line syndrome (PLS)-affected scleractinian coral, Porites lutea, in the reefs of Lakshadweep Islands in the Arabian Sea. Mostly terrestrial species of fungi were isolated...

Ecological States and the Resilience of Coral Reefs

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Tim McClanahan

2002-12-01

Full Text Available We review the evidence for multiple ecological states and the factors that create ecological resilience in coral reef ecosystems. There are natural differences among benthic communities along gradients of water temperature, light, nutrients, and organic matter associated with upwelling-downwelling and onshore-offshore systems. Along gradients from oligotrophy to eutrophy, plant-animal symbioses tend to decrease, and the abundance of algae and heterotrophic suspension feeders and the ratio of organic to inorganic carbon production tend to increase. Human influences such as fishing, increased organic matter and nutrients, sediments, warm water, and transportation of xenobiotics and diseases are common causes of a large number of recently reported ecological shifts. It is often the interaction of persistent and multiple synergistic disturbances that causes permanent ecological transitions, rather than the succession of individual short-term disturbances. For example, fishing can remove top-level predators, resulting in the ecological release of prey such as sea urchins and coral-eating invertebrates. When sea urchins are not common because of unsuitable habitat, recruitment limitations, and diseases, and when overfishing removes herbivorous fish, frondose brown algae can dominate. Terrigenous sediments carried onto reefs as a result of increased soil erosion largely promote the dominance of turf or articulated green algae. Elevated nutrients and organic matter can increase internal eroders of reef substratum and a mixture of filamentous algae. Local conservation actions that attempt to reduce fishing and terrestrial influences promote the high production of inorganic carbon that is necessary for reef growth. However, global climate change threatens to undermine such actions because of increased bleaching and mortality caused by warm-water anomalies, weakened coral skeletons caused by reduced aragonite availability in reef waters, and increased

Is Acropora palmata (elkhorn coral) making a comeback in the Virgin Islands?

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Rogers, Caroline S.

2000-01-01

White band disease (WBD) ravaged Acropora palmata (elkhorn coral) on many coral reefs in the Caribbean in the late 1970’s and 1980’s, including those around St. John and St. Croix, U. S. Virgin Islands—USVI (Gladfelter 1982, Rogers 1985). Quantitative data, photographs, and anecdotal observations indicate WBD killed large stands of elkhorn coral in the USVI from about 1976 until sometime in the late 1980’s. Branching Acroporid species, which are most susceptible to WBD, are also the most vulnerable to storm damage (Rogers et al. 1982). Since 1979, eight hurricanes have passed near or over the USVI. Because elkhorn coral contributed most of the living coral and determined the physical structure of many shallow reef zones, its demise dramatically altered many areas. But now, some of the reefs in the Virgin Islands once again have large, actively growing colonies of this important, reef-building species.

Disease dynamics and potential mitigation among restored and wild staghorn coral, Acropora cervicornis

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Lohr, Kathryn E.; Cameron, Caitlin M.; Williams, Dana E.; Peters, Esther C.

2014-01-01

The threatened status (both ecologically and legally) of Caribbean staghorn coral, Acropora cervicornis, has prompted rapidly expanding efforts in culture and restocking, although tissue loss diseases continue to affect populations. In this study, disease surveillance and histopathological characterization were used to compare disease dynamics and conditions in both restored and extant wild populations. Disease had devastating effects on both wild and restored populations, but dynamics were highly variable and appeared to be site-specific with no significant differences in disease prevalence between wild versus restored sites. A subset of 20 haphazardly selected colonies at each site observed over a four-month period revealed widely varying disease incidence, although not between restored and wild sites, and a case fatality rate of 8%. A tropical storm was the only discernable environmental trigger associated with a consistent spike in incidence across all sites. Lastly, two field mitigation techniques, (1) excision of apparently healthy branch tips from a diseased colony, and (2) placement of a band of epoxy fully enclosing the diseased margin, gave equivocal results with no significant benefit detected for either treatment compared to controls. Tissue condition of associated samples was fair to very poor; unsuccessful mitigation treatment samples had severe degeneration of mesenterial filament cnidoglandular bands. Polyp mucocytes in all samples were infected with suspect rickettsia-like organisms; however, no bacterial aggregates were found. No histological differences were found between disease lesions with gross signs fitting literature descriptions of white-band disease (WBD) and rapid tissue loss (RTL). Overall, our results do not support differing disease quality, quantity, dynamics, nor health management strategies between restored and wild colonies of A. cervicornis in the Florida Keys. PMID:25210660

Deep down on a Caribbean reef: lower mesophotic depths harbor a specialized coral-endosymbiont community

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Bongaerts, P.; Frade, P.R.; Hay, K.B.; Englebert, N.; Latijnhouwers, K.R.W.; Bak, R.P.M.; Vermeij, M.J.A.; Hoegh-Guldberg, O

2015-01-01

The composition, ecology and environmental conditions of mesophotic coral ecosystems near the lower limits of their bathymetric distributions remain poorly understood. Here we provide the first in-depth assessment of a lower mesophotic coral community (60-100 m) in the Southern Caribbean through

Deep down on a Caribbean reef: lower mesophotic depths harbor a specialized coral-endosymbiont community

NARCIS (Netherlands)

Bongaerts, P.; Frade, P.R.; Hay, K.B.; Englebert, N.; Latijnhouwers, K.R.W.; Bak, R.P.M.; Vermeij, M.J.A.; Hoegh-Guldberg, O.

2015-01-01

The composition, ecology and environmental conditions of mesophotic coral ecosystems near the lower limits of their bathymetric distributions remain poorly understood. Here we provide the first in-depth assessment of a lower mesophotic coral community (60–100 m) in the Southern Caribbean through

Doom and boom on a resilient reef: climate change, algal overgrowth and coral recovery.

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Guillermo Diaz-Pulido

Full Text Available Coral reefs around the world are experiencing large-scale degradation, largely due to global climate change, overfishing, diseases and eutrophication. Climate change models suggest increasing frequency and severity of warming-induced coral bleaching events, with consequent increases in coral mortality and algal overgrowth. Critically, the recovery of damaged reefs will depend on the reversibility of seaweed blooms, generally considered to depend on grazing of the seaweed, and replenishment of corals by larvae that successfully recruit to damaged reefs. These processes usually take years to decades to bring a reef back to coral dominance.In 2006, mass bleaching of corals on inshore reefs of the Great Barrier Reef caused high coral mortality. Here we show that this coral mortality was followed by an unprecedented bloom of a single species of unpalatable seaweed (Lobophora variegata, colonizing dead coral skeletons, but that corals on these reefs recovered dramatically, in less than a year. Unexpectedly, this rapid reversal did not involve reestablishment of corals by recruitment of coral larvae, as often assumed, but depended on several ecological mechanisms previously underestimated.These mechanisms of ecological recovery included rapid regeneration rates of remnant coral tissue, very high competitive ability of the corals allowing them to out-compete the seaweed, a natural seasonal decline in the particular species of dominant seaweed, and an effective marine protected area system. Our study provides a key example of the doom and boom of a highly resilient reef, and new insights into the variability and mechanisms of reef resilience under rapid climate change.

Community Structure Of Coral Reefs In Saebus Island, Sumenep District, East Java

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Rizmaadi, Mada; Riter, Johannes; Fatimah, Siti; Rifaldi, Riyan; Yoga, Arditho; Ramadhan, Fikri; Ambariyanto, Ambariyanto

2018-02-01

Increasing degradation coral reefs ecosystem has created many concerns. Reduction of this damage can only be done with good and proper management of coral reef ecosystem based on existing condition. The condition of coral reef ecosystem can be determined by assessing its community structure. This study investigates community structure of coral reef ecosystems around Saebus Island, Sumenep District, East Java, by using satellite imagery analysis and field observations. Satellite imagery analysis by Lyzenga methods was used to determine the observation stations and substrate distribution. Field observations were done by using Line Intercept Transect method at 4 stations, at the depth of 3 and 10 meters. The results showed that the percentage of coral reef coverage at the depth of 3 and 10 meters were 64.36% and 59.29%, respectively, and included in fine coverage category. This study found in total 25 genera from 13 families of corals at all stations. The most common species found were Acropora, Porites, and Pocillopora, while the least common species were Favites and Montastrea. Average value of Diversity, Uniformity and Dominancy indices were 2.94, 0.8 and 0.18 which include as medium, high, and low category, respectively. These results suggest that coral reef ecosystems around Saebus Island is in a good condition.

Thresholds for Coral Bleaching: Are Synergistic Factors and Shifting Thresholds Changing the Landscape for Management? (Invited)

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Eakin, C.; Donner, S. D.; Logan, C. A.; Gledhill, D. K.; Liu, G.; Heron, S. F.; Christensen, T.; Rauenzahn, J.; Morgan, J.; Parker, B. A.; Hoegh-Guldberg, O.; Skirving, W. J.; Strong, A. E.

2010-12-01

As carbon dioxide rises in the atmosphere, climate change and ocean acidification are modifying important physical and chemical parameters in the oceans with resulting impacts on coral reef ecosystems. Rising CO2 is warming the world’s oceans and causing corals to bleach, with both alarming frequency and severity. The frequent return of stressful temperatures has already resulted in major damage to many of the world’s coral reefs and is expected to continue in the foreseeable future. Warmer oceans also have contributed to a rise in coral infectious diseases. Both bleaching and infectious disease can result in coral mortality and threaten one of the most diverse ecosystems on Earth and the important ecosystem services they provide. Additionally, ocean acidification from rising CO2 is reducing the availability of carbonate ions needed by corals to build their skeletons and perhaps depressing the threshold for bleaching. While thresholds vary among species and locations, it is clear that corals around the world are already experiencing anomalous temperatures that are too high, too often, and that warming is exceeding the rate at which corals can adapt. This is despite a complex adaptive capacity that involves both the coral host and the zooxanthellae, including changes in the relative abundance of the latter in their coral hosts. The safe upper limit for atmospheric CO2 is probably somewhere below 350ppm, a level we passed decades ago, and for temperature is a sustained global temperature increase of less than 1.5°C above pre-industrial levels. How much can corals acclimate and/or adapt to the unprecedented fast changing environmental conditions? Any change in the threshold for coral bleaching as the result of acclimation and/or adaption may help corals to survive in the future but adaptation to one stress may be maladaptive to another. There also is evidence that ocean acidification and nutrient enrichment modify this threshold. What do shifting thresholds mean

Distributions and habitat associations of deep-water corals in Norfolk and Baltimore Canyons, Mid-Atlantic Bight, USA

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Brooke, S.D.; Watts, M.W.; Heil, A.D.; Rhode, M.; Mienis, F.; Duineveld, G.C.A.; Davies, A.J.; Ross, S.W.

2017-01-01

A multi-disciplinary study of two major submarine canyons, Baltimore Canyon and Norfolk Canyon, off the US mid-Atlantic coast focused on the ecology and biology of canyon habitats, particularly those supporting deep-sea corals. Historical data on deep-sea corals from these canyons were sparse with

A unique coral community in the mangroves of Hurricane Hole, St. John, US Virgin Islands

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Rogers, Caroline S.

2017-01-01

Corals do not typically thrive in mangrove environments. However, corals are growing on and near the prop roots of red mangrove trees in Hurricane Hole, an area within the Virgin Islands Coral Reef National Monument under the protection of the US National Park Service in St. John, US Virgin Islands. This review summarizes current knowledge of the remarkable biodiversity of this area. Over 30 scleractinian coral species, about the same number as documented to date from nearby coral reefs, grow here. No other mangrove ecosystems in the Caribbean are known to have so many coral species. This area may be a refuge from changing climate, as these corals weathered the severe thermal stress and subsequent disease outbreak that caused major coral loss on the island’s coral reefs in 2005 and 2006. Shading by the red mangrove trees reduces the stress that leads to coral bleaching. Seawater temperatures in these mangroves are more variable than those on the reefs, and some studies have shown that this variability results in corals with a greater resistance to higher temperatures. The diversity of sponges and fish is also high, and a new genus of serpulid worm was recently described. Continuing research may lead to the discovery of more new species.

A study on the recovery of Tobago's coral reefs following the 2010 mass bleaching event.

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Buglass, Salome; Donner, Simon D; Alemu I, Jahson B

2016-03-15

In 2010, severe coral bleaching was observed across the southeastern Caribbean, including the island of Tobago, where coral reefs are subject to sedimentation and high nutrient levels from terrestrial runoff. Here we examine changes in corals' colony size distributions over time (2010-2013), juvenile abundances and sedimentation rates for sites across Tobago following the 2010 bleaching event. The results indicated that since pre-bleaching coral cover was already low due to local factors and past disturbance, the 2010 event affected only particular susceptible species' population size structure and increased the proportion of small sized colonies. The low density of juveniles (mean of 5.4±6.3 juveniles/m(-2)) suggests that Tobago's reefs already experienced limited recruitment, especially of large broadcasting species. The juvenile distribution and the response of individual species to the bleaching event support the notion that Caribbean reefs are becoming dominated by weedy non-framework building taxa which are more resilient to disturbances. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

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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 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 should guard against protecting corallivorous parrotfishes appears to be unwarranted at this stage.

Implications of coral harvest and transplantation on reefs in northwestern Dominica

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Andrew W Bruckner

2010-10-01

Full Text Available 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, 3-20m 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=25cm diameter. Montastraea annularis (complex was the other dominant taxa (20.8% of all corals and colonies were larger (mean=70cm. 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 OID 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 species

Evaluation of Stony Coral Indicators for Coral Reef Management.

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Colonies of reef-building stony corals at 57 stations around St. Croix, U.S. Virgin Islands were characterized by species, size and percentage of living tissue. Taxonomic, biological and physical indicators of coral condition were derived from these measurements and assessed for ...

Coral Sr-U Thermometry

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DeCarlo, T. M.; Gaetani, G. A.; Cohen, A. L.; Foster, G. L.; Alpert, A.; Stewart, J.

2016-12-01

Coral skeletons archive the past two millennia of climate variability in the oceans with unrivaled temporal resolution. However, extracting accurate temperature information from coral skeletons is confounded by "vital effects", which often override the temperature dependence of geochemical proxies. Here, 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. We conducted laboratory experiments to test the temperature and carbonate chemistry controls on abiogenic partitioning of Sr/Ca and U/Ca between aragonite and seawater, and we 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, Sr-U. We tested the model predictions with measured Sr/Ca and U/Ca ratios of fourteen 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. We calibrated Sr-U to instrumental temperature records and found that it captures 93% of mean annual variability (26-30 °C) and predicts temperature within 0.5 °C (1 σ). Conversely, Sr/Ca alone has an error of prediction of 1 °C and often diverges from observed temperature by 3 °C or more. Many of the problems afflicting Sr/Ca - including offsets among neighboring corals and decouplings from temperature during coral stress events - are reconciled by Sr-U. By accounting for the influence of the coral biomineralization process, the Sr-U thermometer may offer significantly improved reliability for reconstructing ocean temperatures from coral

Evolutionary insights into scleractinian corals using comparative genomic hybridizations

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Aranda Manuel

2012-09-01

Full Text Available Abstract Background Coral reefs belong to the most ecologically and economically important ecosystems on our planet. Yet, they are under steady decline worldwide due to rising sea surface temperatures, disease, and pollution. Understanding the molecular impact of these stressors on different coral species is imperative in order to predict how coral populations will respond to this continued disturbance. The use of molecular tools such as microarrays has provided deep insight into the molecular stress response of corals. Here, we have performed comparative genomic hybridizations (CGH with different coral species to an Acropora palmata microarray platform containing 13,546 cDNA clones in order to identify potentially rapidly evolving genes and to determine the suitability of existing microarray platforms for use in gene expression studies (via heterologous hybridization. Results Our results showed that the current microarray platform for A. palmata is able to provide biological relevant information for a wide variety of coral species covering both the complex clade as well the robust clade. Analysis of the fraction of highly diverged genes showed a significantly higher amount of genes without annotation corroborating previous findings that point towards a higher rate of divergence for taxonomically restricted genes. Among the genes with annotation, we found many mitochondrial genes to be highly diverged in M. faveolata when compared to A. palmata, while the majority of nuclear encoded genes maintained an average divergence rate. Conclusions The use of present microarray platforms for transcriptional analyses in different coral species will greatly enhance the understanding of the molecular basis of stress and health and highlight evolutionary differences between scleractinian coral species. On a genomic basis, we show that cDNA arrays can be used to identify patterns of divergence. Mitochondrion-encoded genes seem to have diverged faster than

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

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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.

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

Science.gov (United States)

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.

Osmoadjustment in the Coral Holobiont

KAUST Repository

Röthig, Till

2017-04-01

Coral reefs are under considerable decline. The framework builders in coral reefs are scleractinian corals, which comprise so-called holobionts, consisting of cnidarian host, algal symbionts (genus Symbiodinium), and other associated microbes. Corals are commonly considered stenohaline osmoconformers, possessing limited capability to adjust to salinity changes. However, corals differ in their ability to cope with different salinities. The underlying mechanisms have not yet been addressed. To further understand putative mechanisms involved, I examined coral holobiont osmoregulation conducting a range of experiments on the coral Fungia granulosa. In my research F. granulosa from the Red Sea exhibited pronounced physiological reactions (decreased photosynthesis, cessation of calcification) upon short-term incubations (4 h) to high salinity (55). However, during a 29-day in situ salinity transect experiment, coral holobiont photosynthesis was unimpaired under high salinity (49) indicating acclimatization. F. granulosa microbiome changes after the 29-day high salinity exposure aligned with a bacterial community restructuring that putatively supports the coral salinity acclimatization (osmolyte synthesis, nutrient fixation/cycling). Long-term incubations (7 d) of cultured Symbiodinium exhibited cell growth even at ‘extreme’ salinity levels of 25 and 55. Metabolic profiles of four Symbiodinium strains exposed to increased (55) and decreased (25) salinities for 4 h indicated distinct carbohydrates and amino acids to be putatively involved in the osmoadjustment. Importantly, under high salinity the osmolyte floridoside was consistently increased. This could be corroborated in the coral model Aiptasia and in corals from the Persian/Arabian Gulf, where floridoside was also markedly increased upon short- (15 h) and long-term (>24 months) exposure to high salinity, confirming an important role of floridoside in the osmoadjustment of cnidarian holobionts. This thesis

Energetic differences between bacterioplankton trophic groups and coral reef resistance.

Science.gov (United States)

McDole Somera, Tracey; Bailey, Barbara; Barott, Katie; Grasis, Juris; Hatay, Mark; Hilton, Brett J; Hisakawa, Nao; Nosrat, Bahador; Nulton, James; Silveira, Cynthia B; Sullivan, Chris; Brainard, Russell E; Rohwer, Forest

2016-04-27

Coral reefs are among the most productive and diverse marine ecosystems on the Earth. They are also particularly sensitive to changing energetic requirements by different trophic levels. Microbialization specifically refers to the increase in the energetic metabolic demands of microbes relative to macrobes and is significantly correlated with increasing human influence on coral reefs. In this study, metabolic theory of ecology is used to quantify the relative contributions of two broad bacterioplankton groups, autotrophs and heterotrophs, to energy flux on 27 Pacific coral reef ecosystems experiencing human impact to varying degrees. The effective activation energy required for photosynthesis is lower than the average energy of activation for the biochemical reactions of the Krebs cycle, and changes in the proportional abundance of these two groups can greatly affect rates of energy and materials cycling. We show that reef-water communities with a higher proportional abundance of microbial autotrophs expend more metabolic energy per gram of microbial biomass. Increased energy and materials flux through fast energy channels (i.e. water-column associated microbial autotrophs) may dampen the detrimental effects of increased heterotrophic loads (e.g. coral disease) on coral reef systems experiencing anthropogenic disturbance. © 2016 The Author(s).

Cryobiology of coral fragments.

Science.gov (United States)

Hagedorn, Mary; Farrell, Ann; Carter, Virginia L

2013-02-01

Around the world, coral reefs are dying due to human influences, and saving habitat alone may not stop this destruction. This investigation focused on the biological processes that will provide the first steps in understanding the cryobiology of whole coral fragments. Coral fragments are a partnership of coral tissue and endosymbiotic algae, Symbiodinium sp., commonly called zooxanthellae. These data reflected their separate sensitivities to chilling and a cryoprotectant (dimethyl sulfoxide) for the coral Pocillopora damicornis, as measured by tissue loss and Pulse Amplitude Modulated fluorometry 3weeks post-treatment. Five cryoprotectant treatments maintained the viability of the coral tissue and zooxanthellae at control values (1M dimethyl sulfoxide at 1.0, 1.5 and 2.0h exposures, and 1.5M dimethyl sulfoxide at 1.0 and 1.5h exposures, P>0.05, ANOVA), whereas 2M concentrations did not (Pzooxanthellae. During the winter when the fragments were chilled, the coral tissue remained relatively intact (∼25% loss) post-treatment, but the zooxanthellae numbers in the tissue declined after 5min of chilling (Pzooxanthellae numbers declined in response to chilling alone (P0.05, ANOVA), but it did not protect against the loss of zooxanthellae (Pzooxanthellae are the most sensitive element in the coral fragment complex and future cryopreservation protocols must be guided by their greater sensitivity. Copyright © 2012 Elsevier Inc. All rights reserved.

Acclimatization of symbiotic corals to mesophotic light environments through wavelength transformation by fluorescent protein pigments.

Science.gov (United States)

Smith, Edward G; D'Angelo, Cecilia; Sharon, Yoni; Tchernov, Dan; Wiedenmann, Joerg

2017-07-12

The depth distribution of reef-building corals exposes their photosynthetic symbionts of the genus Symbiodinium to extreme gradients in the intensity and spectral quality of the ambient light environment. Characterizing the mechanisms used by the coral holobiont to respond to the low intensity and reduced spectral composition of the light environment in deeper reefs (greater than 20 m) is fundamental to our understanding of the functioning and structure of reefs across depth gradients. Here, we demonstrate that host pigments, specifically photoconvertible red fluorescent proteins (pcRFPs), can promote coral adaptation/acclimatization to deeper-water light environments by transforming the prevalent blue light into orange-red light, which can penetrate deeper within zooxanthellae-containing tissues; this facilitates a more homogeneous distribution of photons across symbiont communities. The ecological importance of pcRFPs in deeper reefs is supported by the increasing proportion of red fluorescent corals with depth (measured down to 45 m) and increased survival of colour morphs with strong expression of pcRFPs in long-term light manipulation experiments. In addition to screening by host pigments from high light intensities in shallow water, the spectral transformation observed in deeper-water corals highlights the importance of GFP-like protein expression as an ecological mechanism to support the functioning of the coral- Symbiodinium association across steep environmental gradients. © 2017 The Authors.

Coral indicators of past sea-level change: A global repository of U-series dated benchmarks

Science.gov (United States)

Hibbert, Fiona D.; Rohling, Eelco J.; Dutton, Andrea; Williams, Felicity H.; Chutcharavan, Peter M.; Zhao, Cheng; Tamisiea, Mark E.

2016-08-01

Fossil corals provide valuable data for reconstructing past sea levels, as they are often well preserved in the fossil record and can be dated with U-series methods. Here we present a global and internally consistent database of Usbnd Th dated fossil coral sea-level indicators, including full consideration of all (known) associated uncertainties (both vertical and chronological). We include carefully determined taxon-specific depth distributions, rather than blanket depth uncertainty terms as used in most previous work. This is based on a synthesis of extensive modern ecological information on depth ranges. These ranges are found to be spatially variable (between ocean basins, between regions, and on sub-regional scales) because depth itself is not limiting - instead, depth distributions arise from complex physical, chemical, and biological interactions with coral-reef growth, distribution, and composition. One of the main causes for recognition of the greater depth-variability of coral taxa has been the routine inclusion of deep-diving and ROV surveys in coral ecological studies over the past few decades, which has broken through the "shallow-water" bias of early surveys by adding frequent observations on deeper occurrences (although more are needed). It is also clear from our assessment that coral habitat-depth distributions must be determined on the species level to reduce uncertainties in reconstructions of past sea levels, and that application to sea-level studies then requires these studies also to identify fossil corals to the species level. Samples identified only to the genus level give rise to wide uncertainties in habitat depth and, hence, sea level. Our database contains extensive metadata to assist evaluations of dating quality, as well as geomorphic and stratigraphic metadata. We demonstrate with examples how such metadata can help to evaluate sea-level reconstructions, for example by identifying outlier points. One example discusses the Last

Into the depth of population genetics: pattern of structuring in mesophotic red coral populations

Science.gov (United States)

Costantini, Federica; Abbiati, Marco

2016-03-01

Deep-sea reef-building corals are among the most conspicuous invertebrates inhabiting the hard-bottom habitats worldwide and are particularly susceptible to human threats. The precious red coral ( Corallium rubrum, L. 1758) has a wide bathymetric distribution, from shallow up to 800 m depth, and represents a key species in the Mediterranean mesophotic reefs. Several studies have investigated genetic variability in shallow-water red coral populations, while geographic patterns in mesophotic habitats are largely unknown. This study investigated genetic variability of C. rubrum populations dwelling between 55 and 120 m depth, from the Ligurian to the Ionian Sea along about 1500 km of coastline. A total of 18 deep rocky banks were sampled. Colonies were analyzed by means of a set of microsatellite loci and the putative control region of the mitochondrial DNA. Collected data were compared with previous studies. Both types of molecular markers showed high genetic similarity between populations within the northern (Ligurian Sea and Tuscan Archipelago) and the southern (Tyrrhenian and Ionian seas) study areas. Variability in habitat features between the sampling sites did not affect the genetic variability of the populations. Conversely, the patchy distribution of suitable habitats affected populations' connectivity within and among deep coral banks. Based on these results and due to the emphasis on red coral protection in the Mediterranean Sea by international institutions, red coral could be promoted as a `focal species' to develop management plans for the conservation of deep coralligenous reefs, a reservoir of marine biodiversity.

An outbreak of sea cucumbers hinders coral recruitment

Science.gov (United States)

Zhang, Yu-Yang; McCook, Laurence; Jiang, Lei; Lian, Jian-Sheng; Liu, Sheng; Huang, Hui

2018-06-01

An outbreak of a small sessile sea cucumber, Ocnus sanya, occurred on the degraded Luhuitou coral reef in Sanya Bay, Hainan, China. This study explored the pattern of distribution of O. sanya on the reef and the impacts of the high abundance of O. sanya on post-settlement mortality of Pocillopora damicornis recruits. The density of O. sanya ranged from about 500 to over 2000 individuals m-2 with 10.95-23.69% cover on hard substrate. Terracotta tiles with O. sanya on the surface accumulated 19.7% more surface sediment than those without sea cucumbers. Post-settlement P. damicornis recruits had significantly higher mortality on terracotta tiles with O. sanya than those without O. sanya after 21 d. Overall, O. sanya appears to increase sediment stress and inhibit coral recruitment, exacerbating the degradation of Luhuitou Reef. This study raises the possibility that such novel outbreak species could contribute significant additional stress on coral reefs at larger scales.

The future of coral reefs in the US Virgin Islands: is Acropora palmata more likely to recover than Montastraea annularis complex?

Science.gov (United States)

Rogers, Caroline S.; Muller, Erinn; Spitzack, Tony; Miller, Jeff

2008-01-01

Coral diseases have played a major role in the degradation of coral reefs in the Caribbean, including those in the US Virgin Islands (USVI). In 2005, bleaching affected reefs throughout the Caribbean, and was especially severe on USVI reefs. Some corals began to regain their color as water temperatures cooled, but an outbreak of disease (primarily white plague) led to losses of over 60% of the total live coral cover. Montastraea annularis, the most abundant coral, was disproportionately affected, and decreased in relative abundance. The threatened species Acropora palmata bleached for the first time on record in the USVI but suffered less bleaching and less mortality from disease than M. annularis. Acropora palmata and M. annularis are the two most significant species in the USVI because of their structural role in the architecture of the reefs, the large size of their colonies, and their complex morphology. The future of the USVI reefs depends largely on their fate. Acropora palmata is more likely to recover than M. annularis for many reasons, including its faster growth rate, and its lower vulnerability to bleaching and disease.

Hurricanes and coral bleaching linked to changes in coral recruitment in Tobago.

Science.gov (United States)

Mallela, J; Crabbe, M J C

2009-10-01

Knowledge of coral recruitment patterns helps us understand how reefs react following major disturbances and provides us with an early warning system for predicting future reef health problems. We have reconstructed and interpreted historical and modern-day recruitment patterns, using a combination of growth modelling and in situ recruitment experiments, in order to understand how hurricanes, storms and bleaching events have influenced coral recruitment on the Caribbean coastline of Tobago. Whilst Tobago does not lie within the main hurricane belt results indicate that regional hurricane events negatively impact coral recruitment patterns in the Southern Caribbean. In years following hurricanes, tropical storms and bleaching events, coral recruitment was reduced when compared to normal years (p=0.016). Following Hurricane Ivan in 2004 and the 2005-2006 bleaching event, coral recruitment was markedly limited with only 2% (n=6) of colonies estimated to have recruited during 2006 and 2007. Our experimental results indicate that despite multiple large-scale disturbances corals are still recruiting on Tobago's marginal reef systems, albeit in low numbers.

Spectral classifying base on color of live corals and dead corals covered with algae

Science.gov (United States)

Nurdin, Nurjannah; Komatsu, Teruhisa; Barille, Laurent; Akbar, A. S. M.; Sawayama, Shuhei; Fitrah, Muh. Nur; Prasyad, Hermansyah

2016-05-01

Pigments in the host tissues of corals can make a significant contribution to their spectral signature and can affect their apparent color as perceived by a human observer. The aim of this study is classifying the spectral reflectance of corals base on different color. It is expected that they can be used as references in discriminating between live corals, dead coral covered with algae Spectral reflectance data was collected in three small islands, Spermonde Archipelago, Indonesia by using a hyperspectral radiometer underwater. First and second derivative analysis resolved the wavelength locations of dominant features contributing to reflectance in corals and support the distinct differences in spectra among colour existed. Spectral derivative analysis was used to determine the specific wavelength regions ideal for remote identification of substrate type. The analysis results shown that yellow, green, brown and violet live corals are spectrally separable from each other, but they are similar with dead coral covered with algae spectral.

Assessing Coral Community Recovery from Coral Bleaching by ...

African Journals Online (AJOL)

The densities of small colonies were lowest at the northern sites, and small colonies of genera of corals that suffered from high bleaching and mortality during the El Niño Southern Oscillation in 1998 were less abundant in the north. These northern reefs are relatively isolated from sources of coral larvae from reefs in the ...

Coral-bacterial communities before and after a coral mass spawning event on Ningaloo Reef.

Directory of Open Access Journals (Sweden)

Janja Ceh

Full Text Available Bacteria associated with three coral species, Acropora tenuis, Pocillopora damicornis and Tubastrea faulkneri, were assessed before and after coral mass spawning on Ningaloo Reef in Western Australia. Two colonies of each species were sampled before and after the mass spawning event and two additional samples were collected for P. damicornis after planulation. A variable 470 bp region of the 16 S rRNA gene was selected for pyrosequencing to provide an understanding of potential variations in coral-associated bacterial diversity and community structure. Bacterial diversity increased for all coral species after spawning as assessed by Chao1 diversity indicators. Minimal changes in community structure were observed at the class level and data at the taxonomical level of genus incorporated into a PCA analysis indicated that despite bacterial diversity increasing after spawning, coral-associated community structure did not shift greatly with samples grouped according to species. However, interesting changes could be detected from the dataset; for example, α-Proteobacteria increased in relative abundance after coral spawning and particularly the Roseobacter clade was found to be prominent in all coral species, indicating that this group may be important in coral reproduction.

Coral reefs: threats and conservation in an era of global change.

Science.gov (United States)

Riegl, Bernhard; Bruckner, Andy; Coles, Steve L; Renaud, Philip; Dodge, Richard E

2009-04-01

Coral reefs are iconic, threatened ecosystems that have been in existence for approximately 500 million years, yet their continued ecological persistence seems doubtful at present. Anthropogenic modification of chemical and physical atmospheric dynamics that cause coral death by bleaching and newly emergent diseases due to increased heat and irradiation, as well as decline in calcification caused by ocean acidification due to increased CO(2), are the most important large-scale threats. On more local scales, overfishing and destructive fisheries, coastal construction, nutrient enrichment, increased runoff and sedimentation, and the introduction of nonindigenous invasive species have caused phase shifts away from corals. Already approximately 20% of the world's reefs are lost and approximately 26% are under imminent threat. Conservation science of coral reefs is well advanced, but its practical application has often been lagging. Societal priorites, economic pressures, and legal/administrative systems of many countries are more prone to destroy rather than conserve coral-reef ecosystems. Nevertheless, many examples of successful conservation exist from the national level to community-enforced local action. When effectively managed, protected areas have contributed to regeneration of coral reefs and stocks of associated marine resources. Local communities often support coral-reef conservation in order to raise income potential associated with tourism and/or improved resource levels. Coral reefs create an annual income in S-Florida alone of over $4 billion. Thus, no conflict between development, societal welfare, and coral-reef conservation needs to exist. Despite growing threats, it is not too late for decisive action to protect and save these economically and ecologically high-value ecosystems. Conservation science plays a critical role in designing effective strategies.

Changes in biodiversity and functioning of reef fish assemblages following coral bleaching and coral loss

KAUST Repository

Pratchett, M.S.; Hoey, A.S.; Wilson, S.K.; Messmer, V.; Graham, N.A.J.

2011-01-01

Coral reef ecosystems are increasingly subject to severe, large-scale disturbances caused by climate change (e.g., coral bleaching) and other more direct anthropogenic impacts. Many of these disturbances cause coral loss and corresponding changes in habitat structure, which has further important effects on abundance and diversity of coral reef fishes. Declines in the abundance and diversity of coral reef fishes are of considerable concern, given the potential loss of ecosystem function. This study explored the effects of coral loss, recorded in studies conducted throughout the world, on the diversity of fishes and also on individual responses of fishes within different functional groups. Extensive (>60%) coral loss almost invariably led to declines in fish diversity. Moreover, most fishes declined in abundance following acute disturbances that caused >10% declines in local coral cover. Response diversity, which is considered critical in maintaining ecosystem function and promoting resilience, was very low for corallivores, but was much higher for herbivores, omnivores and carnivores. Sustained and ongoing climate change thus poses a significant threat to coral reef ecosystems and diversity hotspots are no less susceptible to projected changes in diversity and function.

Changes in biodiversity and functioning of reef fish assemblages following coral bleaching and coral loss

KAUST Repository

Pratchett, M.S.

2011-08-12

Coral reef ecosystems are increasingly subject to severe, large-scale disturbances caused by climate change (e.g., coral bleaching) and other more direct anthropogenic impacts. Many of these disturbances cause coral loss and corresponding changes in habitat structure, which has further important effects on abundance and diversity of coral reef fishes. Declines in the abundance and diversity of coral reef fishes are of considerable concern, given the potential loss of ecosystem function. This study explored the effects of coral loss, recorded in studies conducted throughout the world, on the diversity of fishes and also on individual responses of fishes within different functional groups. Extensive (>60%) coral loss almost invariably led to declines in fish diversity. Moreover, most fishes declined in abundance following acute disturbances that caused >10% declines in local coral cover. Response diversity, which is considered critical in maintaining ecosystem function and promoting resilience, was very low for corallivores, but was much higher for herbivores, omnivores and carnivores. Sustained and ongoing climate change thus poses a significant threat to coral reef ecosystems and diversity hotspots are no less susceptible to projected changes in diversity and function.

CORAL Server and CORAL Server Proxy: Scalable Access to Relational Databases from CORAL Applications

International Nuclear Information System (INIS)

Valassi, A; Kalkhof, A; Bartoldus, R; Salnikov, A; Wache, M

2011-01-01

The CORAL software is widely used at CERN by the LHC experiments to access the data they store on relational databases, such as Oracle. Two new components have recently been added to implement a model involving a middle tier 'CORAL server' deployed close to the database and a tree of 'CORAL server proxies', providing data caching and multiplexing, deployed close to the client. A first implementation of the two new components, released in the summer 2009, is now deployed in the ATLAS online system to read the data needed by the High Level Trigger, allowing the configuration of a farm of several thousand processes. This paper reviews the architecture of the software, its development status and its usage in ATLAS.

Coral reefs and eutrophication

International Nuclear Information System (INIS)

Stambler, N.

1999-01-01

Coral reefs are found in oligotrophic waters, which are poor in nutrients such as nitrogen, phosphate, and possibly iron. In spite of this, coral reefs exhibit high gross primary productivity rates. They thrive in oligotrophic conditions because of the symbiotic relationship between corals and dinoflagellate algae (zooxanthellae) embedded in the coral tissue. In their mutualistic symbiosis, the zooxanthellae contribute their photosynthetic capability as the basis for the metabolic energy of the whole association, and eventually of a great part of the entire reef ecosystem

Coral reef assessment and monitoring made easy using Coral Point Count with Excel extensions (CPCe software in Calangahan, Lugait, Misamis Oriental, Philippines

Directory of Open Access Journals (Sweden)

S. R. M. Tabugo

2016-03-01

Full Text Available Coral reef communities are considered as the most diverse marine ecosystems that provide food, shelter and protection to marine organisms. It provides many important benefits to humans but often a subject to impairment through human activities. Cascading human influences and climate change appeared as a reason behind its decline. Thus, coral reef monitoring methods are substantial. This study utilized Coral Point Count with Excel extensions (CPCe software, as a means to increase efficiency of coral reef monitoring efforts because it automates, facilitates and speeds the process of random point count analysis and can perform image calibration, planar area and length calculations of benthic features. The method was used to estimate community statistics of benthos based on captured still images for every 1m marked across four 50m transect line (total 200 m at 4.6-5.6m depth. Transect images were assigned with 30 spatial random points for identification. Multiple image frames were combined for each transect length supplying datasheet containing header information, statistical parameters species / substrate type (relative abundance, mean and standard deviation and Shannon-Weaver and Simpson's Index calculation for species diversity. Generated transect datasets were statistically analyzed to give quantitative population estimates over the area of interest. Data from individual frames were combined per transect to allow both inter- and intra- site/transect comparisons. This study reports the current status of coral reefs across Calangahan, Lugait, Misamis Oriental, Philippines and proved the efficiency of CPCe as a tool in reef assessment and monitoring. Results showed that most common genera Porites and Acropora were dominant, with Porites lobata as the most abundant coral species in the area. Moreover, results also showed that there were various diseases present affecting corals leading to increased mortality.

Cellular responses in sea fan corals: granular amoebocytes react to pathogen and climate stressors.

Directory of Open Access Journals (Sweden)

Laura D Mydlarz

Full Text Available BACKGROUND: Climate warming is causing environmental change making both marine and terrestrial organisms, and even humans, more susceptible to emerging diseases. Coral reefs are among the most impacted ecosystems by climate stress, and immunity of corals, the most ancient of metazoans, is poorly known. Although coral mortality due to infectious diseases and temperature-related stress is on the rise, the immune effector mechanisms that contribute to the resistance of corals to such events remain elusive. In the Caribbean sea fan corals (Anthozoa, Alcyonacea: Gorgoniidae, the cell-based immune defenses are granular acidophilic amoebocytes, which are known to be involved in wound repair and histocompatibility. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate for the first time in corals that these cells are involved in the organismal response to pathogenic and temperature stress. In sea fans with both naturally occurring infections and experimental inoculations with the fungal pathogen Aspergillus sydowii, an inflammatory response, characterized by a massive increase of amoebocytes, was evident near infections. Melanosomes were detected in amoebocytes adjacent to protective melanin bands in infected sea fans; neither was present in uninfected fans. In naturally infected sea fans a concurrent increase in prophenoloxidase activity was detected in infected tissues with dense amoebocytes. Sea fans sampled in the field during the 2005 Caribbean Bleaching Event (a once-in-hundred-year climate event responded to heat stress with a systemic increase in amoebocytes and amoebocyte densities were also increased by elevated temperature stress in lab experiments. CONCLUSIONS/SIGNIFICANCE: The observed amoebocyte responses indicate that sea fan corals use cellular defenses to combat fungal infection and temperature stress. The ability to mount an inflammatory response may be a contributing factor that allowed the survival of even infected sea fan corals during a

Microbiome variation in corals with distinct depth distribution ranges across a shallow–mesophotic gradient (15–85 m)

NARCIS (Netherlands)

Glasl, B.; Bongaerts, P.; Elisabeth, N.H.; Hoegh-Guldberg, O.; Herndl, G.J.; Frade, P.R.

2017-01-01

Mesophotic coral ecosystems (MCEs) are generallypoorly studied, and our knowledge of lower MCEs(below 60 mdepth) is largely limited to visual surveys. Here,we provide a first detailed assessment of the prokaryoticcommunity associated with scleractinian corals over a depthgradient to the lower

Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (South Florida). Reef-Building Corals.

Science.gov (United States)

1987-08-01

2S-34. Dustan, P. 1979. Distribution of Davis, G. 1982. A century of natural zooxanthellae and photosynthetic change in coral distribution at the...Perturbation and change in National Climatic Center, Asheville, coral reef communities. Proc. Natl. N.C. 4 pp. Acad. Sci. 79:1678-1681. Neigel, J.E., and...expected to react to environmental changes caused by coastal development. Each profile has sections on taxonomy, life history, ecological role

Robust Performance of Marginal Pacific Coral Reef Habitats in Future Climate Scenarios.

Science.gov (United States)

Freeman, Lauren A

2015-01-01

Coral reef ecosystems are under dual threat from climate change. Increasing sea surface temperatures and thermal stress create environmental limits at low latitudes, and decreasing aragonite saturation state creates environmental limits at high latitudes. This study examines the response of unique coral reef habitats to climate change in the remote Pacific, using the National Center for Atmospheric Research Community Earth System Model version 1 alongside the species distribution algorithm Maxent. Narrow ranges of physico-chemical variables are used to define unique coral habitats and their performance is tested in future climate scenarios. General loss of coral reef habitat is expected in future climate scenarios and has been shown in previous studies. This study found exactly that for most of the predominant physico-chemical environments. However, certain coral reef habitats considered marginal today at high latitude, along the equator and in the eastern tropical Pacific were found to be quite robust in climate change scenarios. Furthermore, an environmental coral reef refuge previously identified in the central south Pacific near French Polynesia was further reinforced. Studying the response of specific habitats showed that the prevailing conditions of this refuge during the 20th century shift to a new set of conditions, more characteristic of higher latitude coral reefs in the 20th century, in future climate scenarios projected to 2100.

Robust Performance of Marginal Pacific Coral Reef Habitats in Future Climate Scenarios.

Directory of Open Access Journals (Sweden)

Lauren A Freeman

Full Text Available Coral reef ecosystems are under dual threat from climate change. Increasing sea surface temperatures and thermal stress create environmental limits at low latitudes, and decreasing aragonite saturation state creates environmental limits at high latitudes. This study examines the response of unique coral reef habitats to climate change in the remote Pacific, using the National Center for Atmospheric Research Community Earth System Model version 1 alongside the species distribution algorithm Maxent. Narrow ranges of physico-chemical variables are used to define unique coral habitats and their performance is tested in future climate scenarios. General loss of coral reef habitat is expected in future climate scenarios and has been shown in previous studies. This study found exactly that for most of the predominant physico-chemical environments. However, certain coral reef habitats considered marginal today at high latitude, along the equator and in the eastern tropical Pacific were found to be quite robust in climate change scenarios. Furthermore, an environmental coral reef refuge previously identified in the central south Pacific near French Polynesia was further reinforced. Studying the response of specific habitats showed that the prevailing conditions of this refuge during the 20th century shift to a new set of conditions, more characteristic of higher latitude coral reefs in the 20th century, in future climate scenarios projected to 2100.

CRED and partners: Environmental Monitoring of Coral Bleaching and Disease in the Hawaiian Islands; Belt Surveys of Coral Population and Disease Assessments at Oahu, Hawaii in 2011

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The field data described herein are part of a joint NESDIS-NMFS project aimed at advancing the understanding of the occurrence, abundance, and outbreak of coral...

CRED and partners: Environmental Monitoring of Coral Bleaching and Disease in the Hawaiian Islands; belt Surveys of Coral Population and Disease Assessments at Hawaii, Hawaii in 2011

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The field data described herein are part of a joint NESDIS-NMFS project aimed at advancing the understanding of the occurrence, abundance, and outbreak of coral...

CRED and partners: Environmental Monitoring of Coral Bleaching and Disease in the Hawaiian Islands; Belt Surveys of Coral Population and Disease Assessments at Oahu, Hawaii in 2010

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The field data described herein are part of a joint NESDIS-NMFS project aimed at advancing the understanding of the occurrence, abundance, and outbreak of coral...

CRED and partners: Environmental Monitoring of Coral Bleaching and Disease in the Hawaiian Islands; belt Surveys of Coral Population and Disease Assessments at Hawaii, Hawaii in 2010

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The field data described herein are part of a joint NESDIS-NMFS project aimed at advancing the understanding of the occurrence, abundance, and outbreak of coral...

CRED and partners: Environmental Monitoring of Coral Bleaching and Disease in the Hawaiian Islands; Belt Surveys of Coral Population and Disease Assessments at Maui, Hawaii in 2010

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The field data described herein are part of a joint NESDIS-NMFS project aimed at advancing the understanding of the occurrence, abundance, and outbreak of coral...

CRED and partners: Environmental Monitoring of Coral Bleaching and Disease in the Hawaiian Islands; Belt Surveys of Coral Population and Disease Assessments at Maui, Hawaii in 2011

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The field data described herein are part of a joint NESDIS-NMFS project aimed at advancing the understanding of the occurrence, abundance, and outbreak of coral...

Evidence of initial coral community recovery at Discovery Bay on Jamaica’s North Coast

Directory of Open Access Journals (Sweden)

M. James C. Crabbe

2014-09-01

Full Text Available Current challenges to coral reef sustainability include overfishing, destructive fishing practices, bleaching, acidification, sea-level rise, starfish, algae, agricultural run-off, coastal and resort development, pollution, diseases, invasive species and hurricanes. We used SCUBA belt transects to record coral cover and digital image analysis in the Dairy Bull Reef off the north coast of Jamaica and found that it is a positive example of how reefs can recover after major environmental disturbance. Live coral cover increased from 13±5% in 2006 to 31±7% in 2008, while live Acropora cervicornis increased from 2±2% in 2006 to 22±7% in 2008. Coral cover levels were maintained until 2012.

Bicarbonate transporters in corals point towards a key step in the evolution of cnidarian calcification

KAUST Repository

Zoccola, Didier

2015-06-04

The bicarbonate ion (HCO3−) is involved in two major physiological processes in corals, biomineralization and photosynthesis, yet no molecular data on bicarbonate transporters are available. Here, we characterized plasma membrane-type HCO3− transporters in the scleractinian coral Stylophora pistillata. Eight solute carrier (SLC) genes were found in the genome: five homologs of mammalian-type SLC4 family members, and three of mammalian-type SLC26 family members. Using relative expression analysis and immunostaining, we analyzed the cellular distribution of these transporters and conducted phylogenetic analyses to determine the extent of conservation among cnidarian model organisms. Our data suggest that the SLC4γ isoform is specific to scleractinian corals and responsible for supplying HCO3− to the site of calcification. Taken together, SLC4γ appears to be one of the key genes for skeleton building in corals, which bears profound implications for our understanding of coral biomineralization and the evolution of scleractinian corals within cnidarians.

Bicarbonate transporters in corals point towards a key step in the evolution of cnidarian calcification

KAUST Repository

Zoccola, Didier; Ganot, Philippe; Bertucci, Anthony; Caminiti-Segonds, Natacha; Techer, Nathalie; Voolstra, Christian R.; Aranda, Manuel; Tambutté , Eric; Allemand, Denis; Casey, Joseph R; Tambutté , Sylvie

2015-01-01

The bicarbonate ion (HCO3−) is involved in two major physiological processes in corals, biomineralization and photosynthesis, yet no molecular data on bicarbonate transporters are available. Here, we characterized plasma membrane-type HCO3− transporters in the scleractinian coral Stylophora pistillata. Eight solute carrier (SLC) genes were found in the genome: five homologs of mammalian-type SLC4 family members, and three of mammalian-type SLC26 family members. Using relative expression analysis and immunostaining, we analyzed the cellular distribution of these transporters and conducted phylogenetic analyses to determine the extent of conservation among cnidarian model organisms. Our data suggest that the SLC4γ isoform is specific to scleractinian corals and responsible for supplying HCO3− to the site of calcification. Taken together, SLC4γ appears to be one of the key genes for skeleton building in corals, which bears profound implications for our understanding of coral biomineralization and the evolution of scleractinian corals within cnidarians.

Coral mucus fuels the sponge loop in warm- and cold-water coral reef ecosystems.