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1.
Glob Chang Biol ; 28(13): 4054-4068, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35420230

RESUMO

Climate change has become the greatest threat to the world's ecosystems. Locating and managing areas that contribute to the survival of key species under climate change is critical for the persistence of ecosystems in the future. Here, we identify 'Climate Priority' sites as coral reefs exposed to relatively low levels of climate stress that will be more likely to persist in the future. We present the first analysis of uncertainty in climate change scenarios and models, along with multiple objectives, in a marine spatial planning exercise and offer a comprehensive approach to incorporating uncertainty and trade-offs in any ecosystem. We first described each site using environmental characteristics that are associated with a higher chance of persistence (larval connectivity, hurricane influence, and acute and chronic temperature conditions in the past and the future). Future temperature increases were assessed using downscaled data under four different climate scenarios (SSP1 2.6, SSP2 4.5, SSP3 7.0 and SSP5 8.5) and 57 model runs. We then prioritized sites for intervention (conservation, improved management or restoration) using robust decision-making approaches that select sites that will have a benign climate under most climate scenarios and models. The modelling work is novel because it solves two important issues. (1) It considers trade-offs between multiple planning objectives explicitly through Pareto analyses and (2) It makes use of all the uncertainty around future climate change. Priority intervention sites identified by the model were verified and refined through local stakeholder engagement including assessments of local threats, ecological conditions and government priorities. The workflow is presented for the Insular Caribbean and Florida, and at the national level for Cuba, Jamaica, Dominican Republic and Haiti. Our approach allows managers to consider uncertainty and multiple objectives for climate-smart spatial management in coral reefs or any ecosystem across the globe.


Assuntos
Antozoários , Ecossistema , Animais , Mudança Climática , Conservação dos Recursos Naturais , Recifes de Corais , Refúgio de Vida Selvagem , Incerteza
2.
Dis Aquat Organ ; 119(2): 153-61, 2016 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-27137073

RESUMO

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.


Assuntos
Antozoários/enzimologia , Antracenos/toxicidade , Catalase/metabolismo , Glutationa Transferase/metabolismo , Animais , Região do Caribe , Regulação Enzimológica da Expressão Gênica
3.
Dis Aquat Organ ; 107(3): 249-58, 2014 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-24429476

RESUMO

Yellow band disease (YBD) is a common and wide-spread Caribbean syndrome that affects the genus Orbicella, a group of species that constitute the framework of Caribbean coral reefs. Previous studies have shown that the structure and function of bacterial assemblages vary between healthy tissues and YBD lesions; however, how the molecular composition of tissues varies as tissues transition from healthy to YBD has not been determined before. The present study provides the first survey of macromolecules found from healthy (H), apparently healthy (AH), transition (TR) and YBD tissues of Orbicella faveolata. For this, we used Fourier-transformed mid-infrared spectroscopy (FTIR) to compare absorption profiles as a proxy for the gross molecular composition of decalcified H, AH and YBD tissues. We found a significantly higher level of infrared absorption for bands assigned to lipids in H tissues compared to YBD tissues, suggesting that lipid compounds are more abundant in compromised tissues in relation to other macromolecules. We also found a lower level of intensity of bands assigned to carbohydrates and proteins in YBD tissues, compared to H and AH tissues. A similar pattern was observed for phospholipidic compounds in relation to fatty acids. This study is the first to show that healthy and YBD-compromised tissues have different infrared absorption profiles, suggesting that alterations in the biochemical composition occur during pathogenesis. Future studies should focus on determining the actual concentration of these compounds in H, AH, TR and YBD tissues and on testing the role of translocation of photoassimilates from H tissues and/or from endolithic algae to YBD tissues.


Assuntos
Antozoários/microbiologia , Espectroscopia de Infravermelho com Transformada de Fourier , Animais , Região do Caribe , Ecossistema , Vibrio
4.
Ann Rev Mar Sci ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227183

RESUMO

As climate change drives health declines of tropical reef species, diseases are further eroding ecosystem function and habitat resilience. Coral disease impacts many areas around the world, removing some foundation species to recorded low levels and thwarting worldwide efforts to restore reefs. What we know about coral disease processes remains insufficient to overcome many current challenges in reef conservation, yet cumulative research and management practices are revealing new disease agents (including bacteria, viruses, and eukaryotes), genetic host disease resistance factors, and innovative methods to prevent and mitigate epizootic events (probiotics, antibiotics, and disease resistance breeding programs). The recent outbreak of stony coral tissue loss disease across the Caribbean has reenergized and mobilized the research community to think bigger and do more. This review therefore focuses largely on novel emerging insights into the causes and mechanisms of coral disease and their applications to coral restoration and conservation.

5.
Sci Adv ; 9(16): eadg3200, 2023 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-37075109

RESUMO

Echinoderm mass mortality events shape marine ecosystems by altering the dynamics among major benthic groups. The sea urchin Diadema antillarum, virtually extirpated in the Caribbean in the early 1980s by an unknown cause, recently experienced another mass mortality beginning in January 2022. We investigated the cause of this mass mortality event through combined molecular biological and veterinary pathologic approaches comparing grossly normal and abnormal animals collected from 23 sites, representing locations that were either affected or unaffected at the time of sampling. Here, we report that a scuticociliate most similar to Philaster apodigitiformis was consistently associated with abnormal urchins at affected sites but was absent from unaffected sites. Experimentally challenging naïve urchins with a Philaster culture isolated from an abnormal, field-collected specimen resulted in gross signs consistent with those of the mortality event. The same ciliate was recovered from treated specimens postmortem, thus fulfilling Koch's postulates for this microorganism. We term this condition D. antillarum scuticociliatosis.


Assuntos
Ecossistema , Ouriços-do-Mar , Animais , Região do Caribe
6.
Dis Aquat Organ ; 100(3): 249-61, 2012 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-22968792

RESUMO

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.


Assuntos
Antozoários , Oceanos e Mares , Temperatura , Animais , Recifes de Corais , Fatores de Tempo
7.
Data Brief ; 37: 107235, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34195310

RESUMO

This dataset contains 2850 photographs of the seafloor in coral communities from Venezuela that were taken during 2017 and 2018. We used a hierarchical experimental design with four random factors representing four different spatial scales: (1) region (hundreds of kilometers), (2) localities (tens of kilometers), (2) reef sites (hundreds of meters) and (3) transects (a couple meters) across the Venezuelan coast. At each site, four 30-m transects were deployed parallel to the coastline, and 15 pictures were taken every other meter at each transect, containing an area of at least 80 × 90cm with enough resolution to identify benthic groups. This dataset covers spatial scales from a few meters to hundreds of kilometers; marine protected areas, and non-protected areas; coastal zones, continental and oceanic islands. These images have the potential to be further used for training researchers in benthic organisms identification, and training artificial intelligence classification algorithms. Also, they represent and updated baseline to perform spatial and temporal comparisons in Venezuela or further studies involving multiple spatial scales in the region.

8.
Rev Biol Trop ; 58 Suppl 3: 189-96, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21299103

RESUMO

This study describes the severity of the 2005 bleaching event at 15 reef sites across Venezuela and compares the 1998 and 2005 bleaching events at one of them. During August and September 2005, bleached corals were first observed on oceanic reefs rather than coastal reefs, affecting 1 to 4% of coral colonies in the community (3 reef sites, n = 736 colonies). At that time, however, no bleached corals were recorded along the eastern coast of Venezuela, an area of seasonal upwelling (3 reefs, n = 181 colonies). On coastal reefs, bleaching started in October but highest levels were reached in November 2005 and January 2006, when 16% of corals were affected among a wide range of taxa (e.g. scleractinians, octocorals, Millepora and zoanthids). In the Acropora habitats of Los Roques (an oceanic reef),no bleached was recorded in 2005 (four sites,n = 643 colonies). At Cayo Sombrero, a coastal reef site, bleaching was less severe in 1998 than in 2005 (9% of the coral colonies involving 2 species vs. 26% involving 23 species, respectively). Our results indicate that bleaching was more severe in 2005 than in 1998 on Venezuelan reefs; however, no mass mortality was observed in either of these two events.


Assuntos
Antozoários , Pigmentação , Animais , Antozoários/classificação , Monitoramento Ambiental , Mortalidade , Dinâmica Populacional , Água do Mar , Venezuela
9.
Rev Biol Trop ; 58 Suppl 1: 51-65, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20873040

RESUMO

In spite of their economic importance, coral reef communities of the world are rapidly decreasing, and an adequate management planification is needed. The benthic and fish communities of Dos Mosquises Sur and Madrizqui at Los Roques National Park, and Caiman and Cayo Norte at Morrocoy National Park, in Venezuela were monitored during 2003 and 2004. The CARICOMP method was used to describe the benthic community, and the AGRRA protocol was applied to the fish community assessment. The benthic cover of five broad living categories (i.e. corals, algae, sponge and octocorals) differed across the sites (Nested ANOVA, p < 0.05), but there were no statistical differences between parks. Despite being on different parks, the benthic cover in Dos Mosquises Sur and Cayo Norte was similar (76% based on Bray-Curtis), whereas Caiman differed greatly (57- 68%) from all other sites. The cover of hard coral, algae, sponges and octocorals was similar between 2003 and 2004 in all four sites. Similarly, the fish community structure of both parks did not change over time, and was dominated by herbivores (Pomacentridac, Scaridae and Acanthuridae). However, commercially important carnivores (e.g. Lutjanids and Serranids) were more abundant in Los Roques than in Morrocoy. Although it was expected that the benthic cover and fish community would reflect greater differences between Los Roques and Morrocoy, only the fish community appeared healthier in Los Roques, whereas Cayo Norte (Morrocoy), had a coral cover similar or higher than both sites of Los Roques. Thus, our results suggest that in Venezuela, oceanic reef sites are not necessarily 'healthier' (i.e. higher coral cover) than land-influenced coral communities. The addition of three new sites and the reincorporation of Caiman has improved and expanded the monitoring capabilities in Venezuela and it represents the first step towards the consolidation of a coral reef monitoring program for the country.


Assuntos
Antozoários/classificação , Recifes de Corais , Monitoramento Ambiental/métodos , Peixes/classificação , Animais , Oceano Atlântico , Densidade Demográfica , Venezuela
10.
PeerJ ; 8: e9082, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32411533

RESUMO

Estimating variability across spatial scales has been a major issue in ecology because the description of patterns in space is extremely valuable to propose specific hypotheses to unveil key processes behind these patterns. This paper aims to estimate the variability of the coral assemblage structure at different spatial scales in order to determine which scales explain the largest variability on ß-diversity. For this, a fully-nested design including a series of hierarchical-random factors encompassing three spatial scales: (1) regions, (2) localities and (3) reefs sites across the Venezuelan territory. The variability among spatial scales was tested with a permutation-based analysis of variance (Permanova) based on Bray-Curtis index. Dispersion in species presence/absence across scales (i.e., ß-diversity) was tested with a PermDisp analysis based on Jaccard's index. We found the highest variability in the coral assemblage structure between sites within localities (Pseudo-F = 5.34; p-value = 0.001, CV = 35.10%). We also found that longitude (Canonical corr = 0.867, p = 0.001) is a better predictor of the coral assemblage structure in Venezuela, than latitude (Canonical corr = 0.552, p = 0.021). Largest changes in ß-diversity of corals occurred within sites (F = 2.764, df1= 35, df2 = 107, p = 0.045) and within localities (F = 4.438, df1= 6, df2 = 29, p = 0.026). Our results suggest that processes operating at spatial scales of hundreds of meters and hundreds of kilometers might both be critical to shape coral assemblage structure in Venezuela, whereas smaller scales (i.e., hundreds of meters) showed to be highly- important for the species turnover component of ß-diversity. This result highlights the importance of creating scale-adapted management actions in Venezuela and likely across the Caribbean region.

11.
PeerJ ; 8: e8429, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32351778

RESUMO

The characteristics of coral reef sampling and monitoring are highly variable, with numbers of units and sampling effort varying from one study to another. Numerous works have been carried out to determine an appropriate effect size through statistical power; however, these were always from a univariate perspective. In this work, we used the pseudo multivariate dissimilarity-based standard error (MultSE) approach to assess the precision of sampling scleractinian coral assemblages in reefs of Venezuela between 2017 and 2018 when using different combinations of number of transects, quadrats and points. For this, the MultSE of 36 sites previously sampled was estimated, using four 30m-transects with 15 photo-quadrats each and 25 random points per quadrat. We obtained that the MultSE was highly variable between sites and is not correlated with the univariate standard error nor with the richness of species. Then, a subset of sites was re-annotated using 100 uniformly distributed points, which allowed the simulation of different numbers of transects per site, quadrats per transect and points per quadrat using resampling techniques. The magnitude of the MultSE stabilized by adding more transects, however, adding more quadrats or points does not improve the estimate. For this case study, the error was reduced by half when using 10 transects, 10 quadrats per transect and 25 points per quadrat. We recommend the use of MultSE in reef monitoring programs, in particular when conducting pilot surveys to optimize the estimation of the community structure.

12.
Ecol Evol ; 10(9): 3844-3855, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32489615

RESUMO

Lionfish (Pterois volitans) have rapidly invaded the tropical Atlantic and spread across the wider Caribbean in a relatively short period of time. Because of its high invasion capacity, we used it as a model to identify the connectivity among nine marine protected areas (MPAs) situated in four countries in the Gulf of Mexico and the Caribbean Sea. This study provides evidence of local genetic differentiation of P. volitans in the Gulf of Mexico and the Caribbean Sea. A total of 475 lionfish samples were characterized with 12 microsatellites, with 6-20 alleles per locus. Departures from Hardy-Weinberg equilibrium (HWE) were found in 10 of the 12 loci, all caused by heterozygous excess. Moderate genetic differentiation was observed between Chiriviche, Venezuela and Xcalak, México localities (F ST = 0.012), and between the Los Roques and the Veracruz (F ST = 0.074) sites. STRUCTURE analysis found that four genetic entities best fit our data. A unique genetic group in the Gulf of Mexico may imply that the lionfish invasion unfolded both in a counterclockwise manner in the Gulf of Mexico. In spite of the notable dispersion of P. volitans, our results show some genetic structure, as do other noninvasive Caribbean fish species, suggesting that the connectivity in some MPAs analyzed in the Caribbean is limited and caused by only a few source individuals with subsequent genetic drift leading to local genetic differentiation. This indicates that P. volitans dispersion could be caused by mesoscale phenomena, which produce stochastic connectivity pulses. Due to the isolation of some MPAs from others, these findings may hold a promise for local short-term control of by means of intensive fishing, even in MPAs, and may have regional long-term effects.

13.
Dis Aquat Organ ; 87(1-2): 33-43, 2009 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-20095239

RESUMO

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.


Assuntos
Antozoários/microbiologia , Antozoários/fisiologia , Animais , Região do Caribe , Demografia , Ecossistema , Oceanos e Mares
14.
Dis Aquat Organ ; 83(3): 195-208, 2009 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-19402453

RESUMO

Geographic assessments of coral diseases are needed to understand their local and geographic spatial-temporal variability. Coral and octocoral diseases and their prevalence were assessed along 4 permanent 10 x 2 m band-transects in each of 3 depth habitats (<4, 5-12 and >15 m) in each of 2 reefs in each of 6 countries across the wider Caribbean during the summer and fall of 2005. A permutational multivariate analysis of variance was used to test variability of major diseases and community level disease prevalence in corals and octocorals among habitats, reefs and countries. The most common and damaging diseases reported for the region were found in most reefs surveyed, but prevalence at the community level was generally low (ca. 2%) increasing from northern to southern latitudes. A significant interaction between sites (nested within country) and depth habitats was found (F = 2.1, df = 12, p = 0.02), with higher prevalence of coral diseases in deep habitats of Culebrita, Puerto Rico (14.8 +/- SE 6.5%) and in shallow habitats of Roldán, Panama (10.2 +/- SE 3.5%). The relative importance of each particular disease was dependent on site and habitat (depth intervals) (F = 1.7, df = 12, p = 0.001), with black band disease more prevalent in shallow habitats of Rita's, Bermuda (1.7 +/- SE 0.4%) and yellow band disease (YBD) more prevalent in deeper habitats of Chub Cut, Bermuda (3.7 +/- SE 0.5%). There was a significant interaction of total octocoral diseases with country and habitat (F = 2.8, df = 10, p = 0.04) with higher prevalence in deeper habitats of Curaçao (25.9 +/- SE 4.2%). Our results indicate that patterns of prevalence of coral and octocoral diseases were not consistent across the different spatial scales, showing differences produced by particular diseases and community composition present. There were no widespread epizootics, but local white plague-II and YBD epizootics were observed in Puerto Rico and other localities.


Assuntos
Antozoários/microbiologia , Animais , Região do Caribe , Demografia
15.
Dis Aquat Organ ; 83(3): 209-22, 2009 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-19402454

RESUMO

Geographic assessments of coral/octocoral diseases affecting major reef-building genera and abundant reef species are important to understand their local and geographic spatial-temporal variability and their impact. The status and spatial variability of major Caribbean coral/octocoral diseases affecting important reef-building coral (Montastraea, Diploria, Siderastrea, Stephanocoenia, Porites, and Agaricia) and common, widespread octocoral genera (Gorgonia and Pseudopterogorgia) was assessed along 4 permanent 10 x 2 m band-transects in each of 3 depth habitats (<4, 5-12 and >15 m) on 2 reefs in 6 countries across the wider Caribbean during the summer and fall of 2005. A permutational multivariate analysis of variance was used to test the spatial variability (countries, reef sites and depth habitats) in prevalence of major diseases in these genera. We found a significant interaction of disease prevalence in the different coral and octocoral genera between reef sites and habitats (depth intervals). Montastraea was primarily affected by both white plague (WP-II) and yellow band disease in deep (16.9 +/- SE 16% and 16.9 +/- SE 2.3%) and intermediate (8.1 +/- SE 1.6% and 15.5 +/- SE 2.3%) depth habitats of Culebrita (Puerto Rico) and Chub Cut (Bermuda), respectively. Prevalence of multiple diseases simultaneously and other compromised-health problems affecting Montastraea colonies varied between 0.2 to 2% and 0.2 to 1.8%, respectively. Agaricia and Diploria were mostly affected by WP-II (0.5 to 16%), black band disease (0.4 to 5%) and Caribbean ciliate infections (0.2 to 12%). Siderastrea and Stephanocoenia were mainly affected by dark spots disease in Curaçao, with higher prevalence in intermediate (40.5 +/- SE 6.2%) and deep (26.6 +/- SE 4.2%) habitats. Aspergillosis and other compromised-health conditions affected Gorgonia ventalina (0.2 to 8%) and other common and widespread octocoral genera (1 to 14%), respectively.


Assuntos
Antozoários/microbiologia , Animais , Região do Caribe , Demografia
16.
Dis Aquat Organ ; 87(1-2): 45-55, 2009 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-20095240

RESUMO

Sexual reproduction is critical to coral population dynamics and the long-term regeneration of coral reefs. Bleaching, disease, and/or anthropogenic-induced tissue/colony loss reduce reproductive output. This is the first attempt to explore the effect of a biotic disease on the reproduction of scleractinian corals. The study aimed to assess the effect of yellow band disease (YBD) on the reproduction of the important Caribbean reef-builder Montastraea faveolata. Tissue samples were collected from diseased, transition, and healthy-looking areas in each of 5 infected colonies and from 5 healthy controls in southwest Puerto Rico. The effect of disease-induced mortality was assessed by collecting samples from the edge and center of surviving small and large, healthy-looking tissue patches from large, previously infected tagged colonies. Fecundity was significantly lower in disease lesions compared to transition and healthy-looking tissues and the controls (99% fewer eggs). Fecundity in transition areas was significantly lower (50%) than in healthy-looking tissues in diseased colonies, which had 23% lower fecundity than control tissues. Although this fecundity drop was not statistically significant, it could indicate a systemic effect of YBD across the colony. Large and small patches had 64 and 84% fewer eggs than controls, respectively, and edge polyps had 97% fewer eggs than those in central control areas. Field observations of the spawning behavior of each tissue area corroborated the histological results. Our results indicate that YBD significantly compromises the reproductive output of M. faveolata, potentially reducing the fitness and consequently, the recovery of this important reef-building species on Caribbean coral reefs.


Assuntos
Antozoários/microbiologia , Antozoários/fisiologia , Animais , Região do Caribe , Ecossistema , Oceanos e Mares , Reprodução/fisiologia , Fatores de Tempo
17.
PeerJ ; 7: e7041, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31198644

RESUMO

Coral disease research encompasses five decades of undeniable progress. Since the first descriptions of anomalous signs, we have come to understand multiple processes and environmental drivers that interact with coral pathologies. In order to gain a better insight into the knowledge we already have, we explored how key topics in coral disease research have been related to each other using network analysis. We reviewed 719 papers and conference proceedings published from 1965 to 2017. From each study, four elements determined our network nodes: (1) studied disease(s); (2) host genus; (3) marine ecoregion(s) associated with the study site; and (4) research objectives. Basic properties of this network confirmed that there is a set of specific topics comprising the majority of research. The top five diseases, genera, and ecoregions studied accounted for over 48% of the research effort in all cases. The community structure analysis identified 15 clusters of topics with different degrees of overlap among them. These clusters represent the typical sets of elements that appear together for a given study. Our results show that while some coral diseases have been studied considering multiple aspects, the overall trend is for most diseases to be understood under a limited range of approaches, e.g., bacterial assemblages have been considerably studied in Yellow and Black band diseases while immune response has been better examined for the aspergillosis-Gorgonia system. Thus, our challenge in the near future is to identify and resolve potential gaps in order to achieve a more comprehensive progress on coral disease research.

19.
PLoS One ; 12(12): e0188564, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29261694

RESUMO

Coastal ecosystems and the livelihoods they support are threatened by stressors acting at global and local scales. Here we used the data produced by the Caribbean Coastal Marine Productivity program (CARICOMP), the longest, largest monitoring program in the wider Caribbean, to evidence local-scale (decreases in water quality) and global-scale (increases in temperature) stressors across the basin. Trend analyses showed that visibility decreased at 42% of the stations, indicating that local-scale chronic stressors are widespread. On the other hand, only 18% of the stations showed increases in water temperature that would be expected from global warming, partially reflecting the limits in detecting trends due to inherent natural variability of temperature data. Decreases in visibility were associated with increased human density. However, this link can be decoupled by environmental factors, with conditions that increase the flush of water, dampening the effects of human influence. Besides documenting environmental stressors throughout the basin, our results can be used to inform future monitoring programs, if the desire is to identify stations that provide early warning signals of anthropogenic impacts. All CARICOMP environmental data are now available, providing an invaluable baseline that can be used to strengthen research, conservation, and management of coastal ecosystems in the Caribbean basin.


Assuntos
Ecossistema , Monitoramento Ambiental/métodos , Estresse Fisiológico , Região do Caribe , Conservação dos Recursos Naturais , Conjuntos de Dados como Assunto , Humanos , Salinidade , Água do Mar , Temperatura
20.
Dis Aquat Organ ; 69(1): 75-8, 2006 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-16703768

RESUMO

This is the first report of a putative pathogenic ciliate protozoan that has been associated with Caribbean corals. Previously, only 2 species of the phylum Ciliophora had been linked to coral diseases, and they were exclusive to the Indo-Pacific region. In this study, a ciliate of the genus Halofolliculina was found on 10 hard coral species at the National Parks of Los Roques and Morrocoy, Venezuela. The general morphology of this ciliate is very similar to that of Halofolliculina corallasia from the Indo-Pacific, which is known to cause skeletal eroding band. None of the other 31 genera in the family Folliculinidae are known to cause diseases in corals or in any other animal species. The presence of this ciliate, which shows a prevalence comparable to that of other epizootics in the Caribbean, suggests it could be a new threat to the coral reefs of this region.


Assuntos
Antozoários/parasitologia , Cilióforos/classificação , Cilióforos/ultraestrutura , Animais , Região do Caribe , Cilióforos/isolamento & purificação , Oceanos e Mares
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