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This dataset accompanies "Spatio temporal variation in octocoral assemblages along a water quality gradient in the northwestern region of Cuba" [1]. Sampling units were quadrats of 1 m

This dataset accompanies ''Spatio temporal variation in octocoral assemblages along a water quality gradient in the northwestern region of Cuba'' [1]. Sampling units were quadrats of 1 m2 (each 1 x 1 m), positioned by a random-systematic design at 10 m depth on the rocky-coral substrate. The number of colonies of octocoral species in thirteen fore reefs was counted to determine the composition, richness and abundance (expressed as density) of octocorals for the period from 2008-2015. Density of six species that most influenced spatial variation of octocoral assemblage structure was compared [1]. Species richness of octocorals was determined in each reef and for the 2008-2015 period. The accumulated species richness was calculated based on 100 randomizations without replacement. This dataset can be used in meta-analysis studies on spatial variations of the structure of octocoral assemblages related to anthropogenic activities and climate variability in the Caribbean Sea, as well as, experimental studies on thresholds to specific pollutants.

The condition of coral reefs in the Cuban Archipelago is poorly known. We aimed to analyse coral assemblages across 199 reef sites belonging to 12 localities. Crest and fore reefs were assessed usi...

This study assessed the coral reef condition of two marine protected areas in the Caribbean: Guanahacabibes National Park, Cuba, and Costa Occidental de Isla Mujeres-Punta Cancun-Punta Nizuc National Park, Mexico, in a two-year period. The analyzed indicators for corals were live coral cover, diameter and height of the colonies, ancient and recent mortalities and abundance of recruits, which were evaluated in quadrats of 1 m 2 . In addition, it was estimated the coverage by morphofunctional groups of macroalgae in 25 × 25 cm quadrats and the density of the Diadema antillarum urchin in 1 m 2 quadrats. The results showed differences between countries at broad spatial scales (hundreds of kilometers). Reefs of both MPAs seem to be in different stages of changes, which have been associated with deterioration of Caribbean reefs, toward the dominance of more resistant, non-tridimensional coral species, causing a decrease of the reef complexity that may leads to the reefs to collapse. At scales of kilometers (within MPAs), a similar pattern was found in reefs of GNP-Cuba and different trends were observed in reefs of CNP-Mexico. The observed differences between CNP-Mexico sites appear to be associated with the current tourism use patterns.

Rivers are the main sources of nutrients to coastal zones. Therefore, the effects of water quality degradation on octocoral assemblages and their relationship with microbiological and physical-chemical variables were determined in reefs close to river basins in the northwestern region of Cuba. The evaluations were carried out in 1 m2 frames at a depth of 10 m in 13 fore reefs. The highest concentrations of the microbiological variables and hydrochemicals and the lowest horizontal visibility in the water column were detected in the reefs near the river basins. The lowest richness, diversity and octocoral density were related to higher concentrations of fecal coliform, total coliform and fecal streptococcal bacteria, sediment accumulation on the bottom and lower visibility. The structure of the octocoral assemblages varied significantly between reefs due to fecal organic pollution. Water quality deterioration in the reefs near the river basins has negatively affected the octocoral assemblages.

Knowledge of the current condition of reef communities is essential for the implementation of marine protected areas (MPAs). In 2014, we assessed the conditions of reefs of two MPAs in the Caribbean: Guanahacabibes National Park (Guanahacabibes), Cuba and Costa Occidental de Isla Mujeres - Punta Cancun - Punta Nizuc National Park (Cancun), Mexico. Within each of the two MPAs studied, we examined two reefs. We took data from fifteen 10-m long transect lines. Indicators included coral cover, diameter of coral colonies, old and recent coral mortalities and coral diseases. The abundance of coral recruits and the density of Diadema antillarum were assessed in 1 m 2 quadrats. The cover of groups of macroalgae was obtained from 25 × 25 cm quadrats. Our data illuminated distinct stages in the loss of reef structure similar to what has been seen by other investigators, particularly the change in the dominance of coral species and the deterioration of the three-dimensional structure of reefs. The Cuevones site (in Cancun), which has been closed to tourism for fifteen years, remains dominated by corals, with a high coral cover (33.36%), but with a species dominance (principally Porites astreoides ), different from the lead species observed in the Caribbean a few decades ago. The reefs of Guanahacabibes (Laberinto and Yemaya) subject to a low diving intensity appear to be at an earlier stage of changes than the Cancun reefs. The coral indicators remains similar to previous reports, so perhaps this can be slowed or reversed. Meanwhile, Manchones in Cancun showed the lowest coral cover (11.49%) and the lowest recruit density (0.6 recruits/m 2 ), probably due to the joint action of the natural pressures and to the heavy influx of visitors these reefs receive.

Marine protected areas have been established as essential components for managing and protecting coral reefs to mitigate natural and anthropogenic stressors. One noteworthy example within the Mexican Caribbean is the Arrecife de Puerto Morelos National Park (APMNP), where several studies on the coral communities have been carried out since 2006. In June 2019, we conducted a study in eight sites of the APMNP applying a coral reef assessment method based on biological indicators of both the benthos and the fish communities. In this paper, we present the quantitative results of our study and provide a qualitative criterion assessing seven condition indexes through a scoring system. We also present a statistical comparison with a previous study carried out in 2016. The general status of coral reefs was classified as regular due to the low values of coral recruitment rate and biomass of key commercial fish species. However, living coral cover average was above 20%, with a slight dominance of framework building coral species and the presence of low values of fleshy algae cover, these being positive indicators. Our study found a higher proportion of reef promoter elements and a lower proportion of detractors, compared to a previous study carried out in 2016.

Acropora palmata is the most important reef-building species in the crest biotopes in the Caribbean Sea. Their populations have been decimated in the last century by disease outbreaks, hurricanes and coral bleaching events. The species has been declared as threatened based on its wide-range decline and poor recovery. We evaluated the status of A. palmata populations across 41 shallow reefs (= sites) around the Cuban archipelago. Density, maximum diameter, and mortality percentage of A. palmata colonies were quantified as main metrics of status. Living coral cover (all species) and reef complexity per site were quantified as well. Metrics of A. palmata varied significantly among sites. A. palmata density was less than 5 colonies 10 m−1 except in one site and only three sites had dominance greater than 50% with respect to the rest of corals. The diameter of A. palmata colonies ranged from 10 to 600 cm, with 70% of sites having a median of less than 200 cm. The mortality was large, with 50% of the sites having more than 50% of mortality, and six sites having 100% mortality. The three sites with better apparent conditions after metric scores were determined were Faro de Cazones, Cayo Fragoso, and Baracoa. A. palmata populations had a bad or regular status in 38 out of 41 studied sites; but, the abundance of erect colonies in many of the sites favored the reef complexity and likely maintained its ecological functions. The low percentage of living coral tissue likely limits the reproductive potential of the species and hence the resiliency of reef crests. In conclusion, the overall status of the species in Cuban archipelago is bad.

Wave exposure can influence community structure and distribution of shallow coral reefs, by affecting organisms both directly and indirectly. To assess the current stony coral community condition under different degrees of wave exposure at a marine protected area of the Gulf of Cazones (SW Cuba), two expeditions were carried out in May 2010 and June 2012. Four sampling sites were sampled at reef crests (1.5 m deep), and twelve at fore-reefs, at 10, 15 and 20 m deep in four geographic locations. Live coral cover, species richness and composition, colony density, and maximum diameter were assessed using the AGRRA 2001 methodology. Multivariate and non-parametric statistics were applied to compare sites. The coral community structure within reef crests was not homogenous. The observed variability of indicators apparently was determined by great coral mortality events resulting from natural disturbances that occurred in the past (hurricanes, bleaching and diseases). Forereef coral communities displayed better condition and lower coral mortality than reef crests. Species richness and coral composition varied, while multivariate and statistical methods did not reveal site grouping with regard to wave exposure. The remaining biological condition indicators were similar among sites, except in the most exposed one, where coral cover and coral size were slightly lower. Wave exposure in the gulf of Cazones seemed not to have a significant influence on differences in condition and structure of the assessed coral communities. Rev. Biol. Trop. 64 (1): 78-93. Epub 2016 March 01. ResumenEl oleaje es una perturbación natural que puede inferir en la estructura y condición de los arrecifes de coral someros, afectando los organismos directa e indirectamente. Para evaluar la condición de comunidades de corales con diferente exposición al oleaje, se realizaron dos expediciones al Área Marina Protegida del Golfo de Cazones durante mayo 2010 y junio 2012. Se escogieron cuatro arrecifes (localidades) ubicados en posiciones diferentes del golfo. Se ubicaron cuatro sitios en la zona de cresta (1.5 m de profundidad) y 12 en la zona de arrecife frontal (en cuatro localidades a 10, 15 y 20 m de profundidad) donde se replicaron transectos lineales (10 m de largo) de muestreo. Se evaluó la cobertura de coral vivo, riqueza y composición por especies, densidad y diámetro máximo de las colonias mediante la metodología AGRRA 2001. Para la comparación entre sitios se aplicaron métodos evaluativos multivariados y análisis estadísticos no paramétricos. La estructura y condición de la comunidad de corales en las crestas fue distinta pero la variabilidad observada parece responder a grandes eventos de mortalidad producto de huracanes, blanqueamientos y enfermedades del pasado. La condición de los arrecifes frontales fue más favorable observándose menor mortalidad coralina. La riqueza y composición por especies fue variable y los métodos estadísticos y multivariados no definieron grupos de sitios con similitud respecto a la exposición al oleaje. Los demás indicadores biológicos de condición fueron parecidos entre sitios, excepto en el más expuesto al oleaje, donde la cobertura y la talla de los corales fueron ligeramente inferiores. En general, la diferente influencia del oleaje dentro del golfo de Cazones, parece no afectar significativamente la estructura y condición de las comunidades coralinas.

Stony coral recruitment in coral reefs at different distances from pollution sources in Habana, Cuba. The effect of pollution on coral recruitment has been insufficiently studied. This research deals with coral recruitment in coastal areas and aimed to determine the variations of density and dominant species of corals recruits in sites at different distances from pollution sources. The composition and structure of stony coral (scleractinian and milleporids) recruit associations were characterized in the fringing reef of Western Havana, Cuba. This reef is influenced by urban pollution from the Almendares River and a sewage outlet located at its mouth. Four sites were sampled on the upper fore reef escarpment at 10m deep every three months between July 2007 and May 2008. A 25cm side quadrat was used to determine the density and taxonomic composition of recruits smaller than 3cm in diameter. Sampling units were placed following a random-systematic pattern. The mean density of recruits was determined both at assemble and species level. Bifactoral ANOVA tests were applied to compare mean densities at both sampling sites and dates. Student-Newman-Keuls test was applied to compare pairs of means. Cluster and nMDS analyses were applied to evaluate between site similarities. The predominant species was Siderastrea siderea followed by S. radians and Porites astreoides. Recruit densities were similar among La Puntilla, Calle 16 and Acuario sites. Lower densities were always found in Malecón. Significant differences in mean stony recruit densities were found both between sites and sampling dates. The statistic analysis did not show significant spatial-temporal interactions. Malecón, the most polluted site, showed the lowest recruit density and the greater presence of species considered as indicators of organic pollution, sedimentation and abrasion. The density of recruit species was higher in October 2007 and lower in May 2008, and it was apparently influenced by reproduction and cold front seasons, respectively. The higher dominance and abundance of S. siderea, S. radians and P. astreoides recruits were apparently due to their high reproductive potential and resistance to disturbances. The identity of dominant species was apparently related to distance from major pollution sources. We highly recommended the replication of this research in other areas of the greater Caribbean region to test the generality of present results and to compare among areas. Future research should take into account the influence of other environmental factors, along with an appraisal of recruit species tolerance to these factors, to better ponder the effect of urban pollution on recruitment. Areas with well assessed pollution regimes are recommended for research. El efecto de la contaminación sobre el reclutamiento ha sido insuficientemente estudiado. Este trabajo trata el tema del reclutamiento en sitios ubicados a diferentes distancias de dos importantes fuentes de contaminación. Se caracterizó la composición y estructura de las asociaciones de reclutas de corales pétreos (escleractinios y milepóridos) al oeste de la Ciudad de La Habana, Cuba. Esta área está influenciada por la contaminación urbana del río Almendares y del emisario submarino construido en su desembocadura. El objetivo de esta investigación fue determinar las variaciones en la densidad y predominio de las especies de reclutas, en sitios ubicados a diferentes distancias de fuentes de contaminación, en distintas épocas de un año. Se muestreó cada tres meses entre julio 2007- mayo 2008. Se escogieron cuatro sitios de muestreo cerca del borde superior del escarpe del arrecife frontal a 10m de profundidad. Se utilizó un marco cuadrado de 25cm de lado de forma aleatoria-sistémica para determinar la densidad y composición taxonómica de reclutas de corales pétreos (colonias menores de 3cm). Para comparar las densidades medias entre sitios y fechas de muestreo se aplicó un análisis de varianza bifactorial. Para comparar los pares de densidades medias se empleó la prueba de Student- Newman-Keuls. La aplicación de un análisis Clasificación Numérica Jerárquica Aglomerativa (Cluster Analysis) y uno de ordenamiento por Escalado Multidimensional no Métrico (nMDS) mostró una distribución en la que los sitios quedaron agrupados en función de sus distancias de las fuentes contaminantes. Predominó Siderastrea siderea seguida por Siderastrea radians y Porites asteroides. Durante el año de muestreo, las densidades de reclutas fueron similares entre La Puntilla, Calle 16 y Acuario. Las menores densidades se observaron siempre en Malecón. Se encontraron diferencias significativas entre las densidades medias de los sitios, así como entre de las distintas fechas de muestreo. El análisis de variancia bifactorial no mostró interacción significativa espacio–tiemporal. Malecón, sitio más contaminado, presentó menor reclutamiento y mayor presencia de especies consideradas indicadoras de contaminación orgánica, sedimentación y abrasión. Las densidades fueron mayores en Octubre 2007 y menores en Mayo 2008, al parecer influenciados por las épocas de reproducción y la acción de los frentes fríos respectivamente. El mayor predominio y abundancia de reclutas de S. siderea, S. radians y P. astreoides parece responder a sus elevados potenciales reproductivos y altas resistencias a disturbios. La identidad de las especies dominantes estuvo relacionada aparentemente con las distancias de las principales fuentes de contaminación. Se recomienda replicar esta investigación en otros lugares de la región del Caribe para probar la generalidad de estos resultados. Estudios futuros debieran tener en cuenta la influencia de otros factores ambientales, junto con una valoración de la tolerancia de las especies de reclutas a estos factores, para ponderar mejor el efecto de la contaminación urbana sobre el reclutamiento.