Download or read book The Environment and Co infection Mediate Disease Risk in Corals Through Impacts on the Microbiome and Immunity written by Allison Merrow Tracy and published by . This book was released on 2019 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: Disease in natural populations depends on the interaction between a host and a parasite, but the environment may also modify this interaction. In this dissertation, I explore how abiotic and biotic components of a host's environment alter health and disease in the sea fan octocoral, Gorgonia ventalina. As ectotherms, corals are particularly sensitive to the environment and thus a priority for studying broader questions about environmental drivers of disease. The microbiome is an essential component of the holobiont that can shift under stressful conditions and alter host susceptibility. In Chapter 1, I compare sea fan and scleractinian bacterial communities across the warm thermal anomaly of 2010. Bacterial communities shifted in sea fans, but not in the more bleaching-susceptible, reef-building scleractinian, Orbicella faveolata. In Chapter 2, I further explore the role of organisms infecting sea fans by studying co-infecting macroparasites. Co-infection is common in nature and has ecological and evolutionary consequences for disease outbreaks. I surveyed 10 sites in Puerto Rico and determined that one parasite suppressed host immunity, yet did not facilitate a second parasite due to the overriding influence of the environment and host demography. A primary goal at the intersection of eco-immunology and disease ecology is to understand how the environment influences host immunity in multi-parasite systems. I investigate this interplay in Chapter 3 by measuring both cellular immunity and immune gene expression. Laboratory experiments reveal distinct immune responses to two parasites, but immune responses in field populations are dominated by the influence of environment and demography. There were no signs that the parasites influence each other in nature. While disease outbreaks occur even in healthy populations, anthropogenic change may alter disease risk. In Chapter 4, I use field surveys and a laboratory experiment to test how warming and copper pollution influence sea fan immunity and disease. Higher copper and temperature increased disease risk, while also driving nonlinear immune responses to a damaging parasite. This dissertation provides insight into the mechanisms through which biotic and abiotic factors structure disease. Understanding sea fan health is also a look to the future, as octocorals are critical for reef habitat in a changing ocean.
Download or read book Coral Health and Disease written by Eugene Rosenberg and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book opens with case studies of reefs in the Red Sea, Caribbean, Japan, Indian Ocean and the Great Barrier Reef. A section on microbial ecology and physiology describes the symbiotic relations of corals and microbes, and the microbial role in nutrition or bleaching resistance of corals. Coral diseases are covered in the third part. The volume includes 50 color photos of corals and their environments
Download or read book The Microbiome and Coral Health written by Sofia Roitman and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Coral reefs are some of the oldest biological structures in the world and serve as the home and breeding grounds for a third of the ocean's marine life, sustaining key species and fisheries. While coral reefs are homes to a multitude of marine species, they contain multitudes as well; much like other animals corals are also holobionts that play host to a number of different microscopic organisms, such as bacteria, dinoflagellates, and archaea, forming a complex system of symbioses at the cellular level that allow corals to grow and survive. This consortium of microorganisms is collectively referred to as the microbiome. In recent years, the coral microbiome in particular has gained traction in the scientific community due to our ever-growing understanding of the key role microbiomes play across ecosystems and organismal health. Bacterial members of the microbiome can provide essential services to their coral host in the form of nutrient cycling, metabolic complementarity, and the production of antibiotic compounds. The coral microbiome's intrinsic tie to coral health is of growing importance today given the steady decline of coral reefs worldwide. However, studies show that coral microbiomes can vary widely based on species, region, temperature, depth, and season, as well as in their response to different stressors. Current microbiome studies are thus hindered by the lack of baselines (that is, a description of the microbiome of a healthy coral, including transient and stable microbial members) for healthy coral microbiomes, limiting our ability to study the relationship between environmental stressors and holobiont response. My dissertation aims to address both the need for microbial baselines as well as to aid in the understanding of the relationship between the coral microbiome and coral health in the face of abiotic and biotic stressors. To that end, my first data chapter aims to determine how the microbial communities of two Caribbean coral species vary when infected with disease, as well as identify microbial "footprints" pertaining to each disease and microbial community members that are significantly altered in the face of an infection, which could provide insight on changes to the structure and overall function of the corals' microbiome when infected. My second data chapter aims to determine the relationship between the coral microbiome and coral survivorship in poor water quality conditions through a reciprocal transplant between a clear-water reef and a surviving turbid-water reef, as well as to explore the effects of such an environment on the sediment microbiome using metagenomic sequencing. Finally, my third data chapter aims to establish correlations between anthropogenically-impacted reef sites and the reef environment microbiome, and to therefore propose the future use of environmental microbial metagenomes as sources of information on bioindicator taxa, as well as genes and metabolic pathways that could also be used for indicator purposes.
Download or read book Coral Reefs and Climate Change written by Jonathan Turnbull Phinney and published by American Geophysical Union. This book was released on 2006-01-10 with total page 251 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published by the American Geophysical Union as part of the Coastal and Estuarine Studies, Volume 61. The effects of increased atmospheric carbon dioxide and related climate change on shallow coral reefs are gaining considerable attention for scientific and economic reasons worldwide. Although increased scientific research has improved our understanding of the response of coral reefs to climate change, we still lack key information that can help guide reef management. Research and monitoring of coral reef ecosystems over the past few decades have documented two major threats related to increasing concentrations of atmospheric CO2: (1) increased sea surface temperatures and (2) increased seawater acidity (lower pH). Higher atmospheric CO2 levels have resulted in rising sea surface temperatures and proven to be an acute threat to corals and other reef-dwelling organisms. Short periods (days) of elevated sea surface temperatures by as little as 1–2°C above the normal maximum temperature has led to more frequent and more widespread episodes of coral bleaching-the expulsion of symbiotic algae. A more chronic consequence of increasing atmospheric CO2 is the lowering of pH of surface waters, which affects the rate at which corals and other reef organisms secrete and build their calcium carbonate skeletons. Average pH of the surface ocean has already decreased by an estimated 0.1 unit since preindustrial times, and will continue to decline in concert with rising atmospheric CO2. These climate-related Stressors combined with other direct anthropogenic assaults, such as overfishing and pollution, weaken reef organisms and increase their susceptibility to disease.
Download or read book A Research Review of Interventions to Increase the Persistence and Resilience of Coral Reefs written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2019-04-05 with total page 259 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coral reef declines have been recorded for all major tropical ocean basins since the 1980s, averaging approximately 30-50% reductions in reef cover globally. These losses are a result of numerous problems, including habitat destruction, pollution, overfishing, disease, and climate change. Greenhouse gas emissions and the associated increases in ocean temperature and carbon dioxide (CO2) concentrations have been implicated in increased reports of coral bleaching, disease outbreaks, and ocean acidification (OA). For the hundreds of millions of people who depend on reefs for food or livelihoods, the thousands of communities that depend on reefs for wave protection, the people whose cultural practices are tied to reef resources, and the many economies that depend on reefs for fisheries or tourism, the health and maintenance of this major global ecosystem is crucial. A growing body of research on coral physiology, ecology, molecular biology, and responses to stress has revealed potential tools to increase coral resilience. Some of this knowledge is poised to provide practical interventions in the short-term, whereas other discoveries are poised to facilitate research that may later open the doors to additional interventions. A Research Review of Interventions to Increase the Persistence and Resilience of Coral Reefs reviews the state of science on genetic, ecological, and environmental interventions meant to enhance the persistence and resilience of coral reefs. The complex nature of corals and their associated microbiome lends itself to a wide range of possible approaches. This first report provides a summary of currently available information on the range of interventions present in the scientific literature and provides a basis for the forthcoming final report.
Download or read book Diseases of Coral written by Cheryl M. Woodley and published by John Wiley & Sons. This book was released on 2016-01-26 with total page 613 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coral disease is quickly becoming a crisis to the health and management of the world’s coral reefs. There is a great interest from many in preserving coral reefs. Unfortunately, the field of epizootiology is disorganized and lacks a standard vocabulary, methods, and diagnostic techniques, and tropical marine scientists are poorly trained in wildlife pathology, veterinary medicine, and epidemiology. Diseases of Coral will help to rectify this situation.
Download or read book A Decision Framework for Interventions to Increase the Persistence and Resilience of Coral Reefs written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2019-08-29 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coral reefs are critical to ocean and human life because they provide food, living area, storm protection, tourism income, and more. However, human-induced stressors, such as overfishing, sediment, pollution, and habitat destruction have threatened ocean ecosystems globally for decades. In the face of climate change, these ecosystems now face an array of unfamiliar challenges due to destructive rises in ocean temperature, acidity and sea level. These factors lead to an increased frequency of bleaching events, hindered growth, and a decreasing rate of calcification. Research on interventions to combat these relatively new stressors and a reevaluation of longstanding interventions is necessary to understand and protect coral reefs in this changing climate. Previous research on these methods prompts further questions regarding the decision making process for site-specific interventions. A Decision Framework for Interventions to Increase the Persistence and Resilience of Coral Reefs builds upon a previous report that reviews the state of research on methods that have been used, tested, or proposed to increase the resilience of coral reefs. This new report aims to help coral managers evaluate the specific needs of their site and navigate the 23 different interventions described in the previous report. A case study of the Caribbean, a region with low coral population plagued by disease, serves as an example for coral intervention decision making. This report provides complex coral management decision making tools, identifies gaps in coral biology and conservation research, and provides examples to help individuals and communities tailor a decision strategy to a local area.
Download or read book Genetic Bases of Immunity and Disease Resistance to White Band Disease in the Caribbean Staghorn Coral Acropora Cervicornis written by Silvia Libro and published by . This book was released on 2014 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past thirty years, marine disease outbreaks have increased significantly, producing dramatic alterations in marine ecosystems worldwide. Reef-building corals have been particularly vulnerable to the increase in new epizootic diseases, and yet many aspects of the coral-pathogen interaction remain unresolved, including how corals respond to disease infections. One example is represented by White Band Disease (WBD), a coral disease that causes rapid tissue degradation in acroporid corals. Since the 1970`s, WBD outbreaks have caused catastrophic mass mortalities of two foundation species on Caribbean coral reefs, the staghorn coral "Acropora cervicornis" and the elkhorn coral A. palmata, which populations have collapsed by up to 98%. The etiology of WBD has not been fully elucidated yet, but presence of disease resistant genotypes and local recovery from WBD in natural populations of "A. cervicornis" suggest that staghorn corals have the ability to fight the disease and that genetic mechanisms may underlie resistance to WBD. My thesis focuses on understanding the genetic basis of coral host immunity and resistance to WBD in the endangered staghorn coral "Acropora cervicornis" using next-generation sequencing (RNA-seq). To identify the key mediators of the immune response of staghorn corals to WBD disease, I conducted transcriptome analysis of healthy and WBD-infected staghorn corals from natural populations. My results show that WBD causes expression changes in 4% of the coral host transcriptome, and that the immune response to staghorn corals is characterized by pathogen recognition, production of reactive oxygen species, apoptosis and stress response genes, as well as eicosanoids, a class of lipid metabolites including leukotrienes and prostaglandins, that had not previously identified as immune mediators in scleractinian corals. Using common garden experiments, I exposed resistant and susceptible corals to healthy and to WBD-infected grafts to identify expression changes associated to resistance during disease exposure (WBD grafts) and allorecognition (healthy grafts). I found that expression patterns associated to disease resistance are independent from exposure to WBD and do not include any of the immune pathways involved in the response against WBD corals. Rather, the gene expression signature of WBD resistance encompasses a very small number of genes that are constitutively up- or down-regulated in resistant corals. Mechanisms involved in WBD resistance include RNA interference-mediated post-transcriptional regulation, antiviral defense and heat stress response, suggesting a link between thermal stress tolerance and disease resistance. Expression changes associated to exposure revealed that allorecognition only induces expression changes for a small subset of genes involved in general stress response and nematocyst discharge, while exposure to WBD has a large-scale effect on the transcriptome. Consistent with the results described above, disease exposure resulted in enhanced pathogen recognition, synthesis of ROS and production of eicosanoids. Hallmarks of early stage response to WBD included Toll-like receptors (TLR)-mediated NF-kB signaling, Prophenolxidase activity and increased expression of Heath shock proteins and antivirals. These results also show that eicosanoids in staghorn corals are involved in the response to WBD but not to allogeneic tissue exposure and mechanical injury, indicating a pivotal role during pathogen infections rather than during wound repair and general stress response. Taken together, these results indicate that "A. cervicornis" mounts a powerful response against disease infections involving several innate immune pathways. In addition, this response does not appear to be a general immune response, as indicated by the highly divergent expression profiles of corals exposed to WBD and healthy grafts, suggesting that "A. cervicornis" is able to discriminate between pathogen attack and allorecognition. By characterizing the genetic signature of resistance to WBD, this research represents a valuable contribution to understanding how corals respond to disease and can serve as a conservation tool to identify and farm WBD-resistant genotypes for large scale restoration of the endangered Caribbean "Acropora". This knowledge is critical to the conservation of threatened reef corals and has direct conservation implications for the endangered Caribbean staghorn coral "A. cervicornis".
Download or read book The Future of Coral Reefs Subject to Rapid Climate Change Lessons from Natural Extreme Environments written by Emma F. Camp and published by Frontiers Media SA. This book was released on 2019-01-22 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Examination of corals and reef-associated organisms which endure in extreme coral reef environments is challenging our understanding of the conditions that organisms can survive under. By studying individuals naturally adapted to unfavorable conditions, we begin to better understand the important traits required to survive rapid environmental and climate change. This Research Topic, comprising reviews, and original research articles, demonstrates the current state of knowledge regarding the diversity of extreme coral habitats, the species that have been studied, and the knowledge to-date on the mechanisms, traits and trade-offs that have facilitated survival.
Download or read book Global Climate Change and Coral Reefs written by Clive R. Wilkinson and published by World Conservation Union. This book was released on 1994 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: A global overview of the potential impacts of climate change and sea level rise on coral reefs, and of the implications of such impacts for ecological sustainable use of coral reefs. Includes information on the status and trends of reef conservation and use around the world, and suggestions for management of reefs in a changing world.
Download or read book Microbial Communities of Healthy and Diseased Corals written by James S. Klaus and published by . This book was released on 2005 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this dissertation is threefold: (1) to determine how coral microbial communities change in response to various environmental factors; (2) to define numerical scales to identify pristine and impacted corals and coral reef ecosystems; and (3) to establish a baseline from which an understanding of healthy microbial communities and environmental impacts can be integrated into coral disease studies ... Corals health is dependent upon maintaining delicate interactions with zooxanthellae, microbes, and the environment. However, a clear understanding of these interactions has been impeded by an inability to identify the biologic players involved. The tools of molecular genetics, as applied in this thesis, are beginning to identify the true diversity of coral reefs, and are radically changing our understanding of key reef ecosystem processes.
Download or read book Investigating the Drivers of Microbial Community Dynamics in Caribbean Reef building Corals written by Courtney Dunphy and published by . This book was released on 2020 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Coral-associated microbial communities (microbiomes) have been increasingly recognized as important contributors to key functions that promote the health and persistence of their hosts. Rapid global climate change can impact the coral microbiome symbiosis and lead to negative shifts in microbial community structure that can ultimately lead to coral disease and the destruction of the coral reef. Conversely, microbes may contribute positively to coral resistance and resilience by rapidly adapting to varying environmental conditions. This dissertation uses a combination of survey, experimental, and theoretical methods to (i) define the characteristics of a healthy coral microbiome, (ii) identify the underlying mechanisms generating variability in coral microbiomes, and (iii) evaluate how processes operating at multiple levels of biological organization interact to regulate the microbiome in response to external perturbations and disease incidence. Chapter 2 describes a field survey in which I examined the natural microbiome variability associated with six Caribbean coral species (Acropora cervicornis, A. palmata, Diploria labyrinthinformis, [Pseudodiploria] D. strigosa, Porites astreoides, and P. furcata) from three genera at multiple reef sites over a period of one year. I identified differences in microbiome composition between coral genera and species that persisted across geographic and temporal scales, indicating that local processes such as coral host identity likely plays a strong role in microbiome structure. In addition, utilizing network analysis, I demonstrated that the strength of host identity over microbiome composition varied across coral genera. I further identified ubiquitous bacterial phylotypes (i.e., core microbiome) for each coral genus, and revealed that bacterial communities in corals show taxonomical, and potentially functional, redundancy in both the whole community and the core coral microbiome. Chapter 3 builds on this finding by assessing whether natural variability across coral genera is indicative of resistance to external disturbances. Using a common-garden field experiment, I identified and quantified the microbial community response after exposing three coral genera (A. cervicornis, D. strigosa, and P. astreoides) to a pulse perturbation consisting of a large dose of broad-spectrum antibiotics. I showed that all coral host microbiomes exhibited a high degree of resistance to the disturbance, however, the stability of their microbial communities varied across coral host species. Coral species that previously displayed the highest variability and community turnover (Chapter 2), here, exhibited the greatest resistance to the experimental perturbations. To resolve this apparent paradox, I developed a novel stage- structured mathematical model of host-microbial dynamics that showed post-disturbance stability depended on whether microbiome control (via antimicrobial compounds) was regulated by the coral host or within the microbiome itself. These results highlight that understanding how processes operate across multiple levels of biological organization interact to regulate microbiomes is critical to both predict and mitigate the effects of environmental variation. Finally, host-microbiome interactions play an important role in a host's susceptibility to disease, therefore, predicting when and how healthy microbiome symbioses break down represents an essential challenge for coral disease ecology. To address this issue, Chapter 4 utilized a tank-based transmission experiment using White Band Disease (WBD) on the staghorn coral A. cervicornis. This chapter compares the effects of broad-spectrum antibiotics and two rounds of exposure from healthy and diseased coral tissue homogenates on microbiome diversity and structure over time. This exposure treatment allowed me to test key factors associated with deterministic and stochastic microbial community assembly. I identified a positive legacy effect of antibiotics on coral-microbiome diversity and health that persisted through time. I determined there was a weak probiotic effect, and that a more specific and targeted exposure to beneficial microbes is necessary to potentially establish a positive probiotic effect. I further determined there was no evidence of a priority effect, as microbes from healthy hosts were unable to suppress the invasion of microbes from diseased hosts purely by colonizing first. Thus, the outcome of competition does not depend on initial conditions and is therefore more predictable"--Author's abstract.
Download or read book Proceedings of the Colloquium on Global Aspects of Coral Reefs Health Hazards and History written by Robert N. Ginsburg and published by Atlantic Reef Committee. This book was released on 1994 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Symbiotic Microbiomes of Coral Reefs Sponges and Corals written by Zhiyong Li and published by . This book was released on 2019 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the symbiotic microbiomes of invertebrates in coral reefs, especially sponges and corals. It provides in-depth and up-to-date reviews on the microbial structure and diversity, metabolism and function, symbiosis and coevolution, environment and adaption, and bioactive potentials. Meanwhile, the future perspectives will be discussed according to the existing problems and the development trend. This book will be of particular interest to the professionals in marine ecology, marine biotechnology, as well as medicinal chemists and molecular biologists.
Download or read book Coral reef resilience and resistance to bleaching written by and published by IUCN. This book was released on 2005 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides synthesis of current scientific knowledge on coral reef resilience and resistance to bleaching, and highlights resilience and resistance factors and some knowledge gaps. Discusses tools and strategies to enhance resilience, including the use of well-designed networks of marine protected areas and integrated coastal management.
Download or read book Trait mediated Effects and the Extended Phenotype written by Anya Leard Brown and published by . This book was released on 2018 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: Interaction modifiers can induce changes in (a) physio-chemical conditions and (b) phenotypes of individuals, including host-associated microbial communities, thus influencing species interactions. Among the increasingly best-studied holobionts (hosts + microbes) are corals. Corals experience a myriad of stressors, including interactions with algae, which can decrease coral growth and survival. A hypothesized mechanism underlying the deleterious effects of algae on corals involves the release of dissolved organic carbon (DOC), which stimulates microbial growth leading to changes in microbial communities/hypoxia. The microbial effects of algae on corals are context-dependent, and change depending on the physical environment (e.g., water flow) and the presence of other species. One such species is the sessile vermetid gastropod, Cereasignum maximum, which uses its mucus net for food capture. When a mucus net covers a coral in contact with algae, the net can exacerbate the negative effects of algae on corals by 1) decreasing water flow, 2) synergistically decreasing coral growth, and/or 3) leading to changes in the coral's microbial communities, favoring potentially pathogenic groups and/or enhancing stress by changing the concentration of dissolved materials. Using a series of field surveys, lab flume studies, and field experiments, I found that mucus nets reduce water flow and lower oxygen concentrations at the surface of corals. Algal presence led to the greatest changes in microbial communities. Vermetids and algae decrease different aspects of coral growth. I hypothesized that the absence of a strong response of corals to vermetids arose because corals may have acclimatized to the presence of vermetids. To test this hypothesis I conducted a reciprocal transplant study of corals with and without previous exposure to vermetids. I found significant effects of prior exposure of vermetids on coral traits, and plasticity of the microbiome, but no evidence of a weakened vermetid effect. Interestingly, I also found genetic differences between coral on reefs with vs. without vermetids, and suggest vermetids may be part of a coral's extended phenotype. My dissertation demonstrated interaction modifications and trait-mediated effects of vermetids and algae on corals, and showed novel, but likely general mechanisms for these effects involving changes in the coral's microbial community.
Download or read book Coral Reef Conservation and Restoration in the Omics Age written by Madeleine J. H. van Oppen and published by Springer Nature. This book was released on 2022-09-12 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: The rapid demise of coral reefs worldwide has spurred efforts to develop innovative conservation and restoration methods. Many of these rely on omics approaches to produce genetic, genomic, transcriptomic, epigenomic or metabolomic data to inform conservation and restoration interventions. This book provides the state of play of this field. It discusses topics ranging from how genomic and environmental DNA (eDNA) data can be used to inform marine protected area design and cryopreservation strategies, the use of knowledge on adaptive genetic and epigenetic variation to maximise environmental stress tolerance of coral stock, harnessing transcriptome data to develop early warning markers, the use of microbial symbiont omics data in guiding restoration strategies, to applications of metabolomics and genetic engineering. How best to translate omics data to resource managers is also discussed.
