Search

Summary: There are a few baseline reef‐systems available for understanding the microbiology of healthy coral reefs and their surrounding seawater. Here, we examined the seawater microbial ecology of 25 Northern Caribbean reefs varying in human impact and protection in Cuba and the Florida Keys, USA, by measuring nutrient concentrations, microbial abundances, and respiration rates as well as sequencing bacterial and archaeal amplicons and community functional genes. Overall, seawater microbial composition and biogeochemistry were influenced by reef location and hydrogeography. Seawater from the highly protected 'crown jewel' offshore reefs in Jardines de la Reina, Cuba had low concentrations of nutrients and organic carbon, abundant Prochlorococcus, and high microbial community alpha diversity. Seawater from the less protected system of Los Canarreos, Cuba had elevated microbial community beta‐diversity whereas waters from the most impacted nearshore reefs in the Florida Keys contained high organic carbon and nitrogen concentrations and potential microbial functions characteristic of microbialized reefs. Each reef system had distinct microbial signatures and within this context, we propose that the protection and offshore nature of Jardines de la Reina may preserve the oligotrophic paradigm and the metabolic dependence of the community on primary production by picocyanobacteria. [ABSTRACT FROM AUTHOR]

Scleractinian corals are bathed in a sea of planktonic and particle‐associated microorganisms. The metabolic products of corals influence the growth and composition of microorganisms, but interactions between corals and seawater microorganisms are underexplored. We conducted a field‐based survey to compare the biomass, diversity, composition, and functional capacity of microorganisms in small‐volume seawater samples collected adjacent to five coral species with seawater collected > 1 m away from the reef substrate on the same reefs. Seawater collected close to corals generally harbored copiotrophic‐type bacteria and its bacterial and archaeal composition was influenced by coral species as well as the local reef environment. Trends in picoplankton abundances were variable and either increased or decreased away from coral colonies based on coral species and picoplankton functional group. Genes characteristic of surface‐attached and potentially virulent microbial lifestyles were enriched in near‐coral seawater compared to reef seawater. There was a prominent association between the coral Porites astreoides and the coral symbiont Endozoicomonas, suggesting recruitment and/or shedding of these cells into the surrounding seawater. This evidence extends our understanding of potential species‐specific and reef site‐influenced microbial interactions that occur between corals and microorganisms within this near‐coral seawater environment that we propose to call the "coral ecosphere." Microbial interactions that occur within the coral ecosphere could influence recruitment of coral‐associated microorganisms and facilitate the transfer of coral metabolites into the microbial food web, thus fostering reef biogeochemical cycling and a linkage between corals and the water column. [ABSTRACT FROM AUTHOR]

Caribbean coral reefs are biodiversity-rich habitats which provide numerous ecosystem services with both ecological and economical values, but nowadays they are severely degraded. In particular, populations of the major framework-building coral Orbicella faveolata have declined sharply, and therefore, understanding how these threatened coral populations are interconnected and how demographic changes have impacted their genetic diversity is essential for their management and conservation. Previous population genetic surveys showed that gene flow in this species is sometimes locally restricted in the Caribbean; however, little genetic data are available for Cuban populations. Here, we analyzed the variation at the mitochondrial DNA control region and six microsatellite loci from O. faveolata colonies from five distant localities representing most of the main coral reefs around Cuba. Both genetic markers showed evidence of genetic differentiation between the northwestern area (Colorados Archipelago) and the other reefs. Colonies from the Colorados Archipelago harbored the largest number of unique mtDNA haplotypes and microsatellite alleles, which suggests long-term large population size or gene flow from other areas of the Caribbean. These results indicate that the Colorados Archipelago area is particularly important for O. faveolata populations and it is well suited for reef management and restoration efforts. [ABSTRACT FROM AUTHOR]

Cuban coral reefs have been called the "crown jewels of the Caribbean Sea," but there are few comparative data to validate this claim. Here, we provide an overview of Cuban coral reefs based on surveys carried out between 2010 and 2016 on seven of the main Cuban coral reef systems: Havana, Artemisa, Los Colorados, Punta Francés, Los Canarreos Archipelago, Península Ancón, and Jardines de la Reina. Ecological indicators were evaluated for each of these areas at the community level. Results suggest differences among benthic communities (corals, sponges, and gorgonians) that are most evident for reefs that develop near highly urbanized areas, such as Havana, than for those far from the coast and less accessible. Offshore reefs along the south-central coast at Jardines de la Reina and Península Ancón exhibited high coral density and diversity. Acropora cervicornis (Lamarck, 1816) and the Orbicella complex corals were uncommon, possibly indicating losses prior to our study due to coral diseases or competition with macroalgae. Siderastrea siderea (Ellis and Solander, 1786) was the most consistently-abundant species at all reef sites. The ecological condition at Jardines de la Reina and Península Ancón is comparatively healthy. Our study supports claims that some Cuban coral reef systems are probably among the best preserved in the Caribbean basin, but other highly impacted areas exhibit many of the degradation patterns that are common to the rest of the Caribbean region. Strong conservation strategies are required with regard to subsistence fisheries and pollution at highly-impacted reefs to stop further degradation, and reefs that appear healthy need protection to avoid degradation and maintain resilience. [ABSTRACT FROM AUTHOR]

Cuba is an ecological rarity in Latin America and the Caribbean region. Its complex political and economic history shows limited disturbances, extinctions, pollution, and resource depletion by legal or de facto measures. Vast mangroves, wetlands, and forests play key roles in protecting biodiversity and reducing risks of hazards caused or aggravated by climate change. Cuba boasts coral reefs with some of the region's greatest fish biomass and coral cover. Although it has set aside major protected areas that safeguard a host of endemic species, Cuba's environment is by no means pristine. Through much of its early history, deforestation and intensive agricultural production under colonial then neocolonial powers was the norm. Using remote sensing, we find Cuba's land today is 45% devoted to agricultural, pasturage, and crop production. Roughly 77% of Cuba's potential mangrove zone is presently in mangrove cover, much of it outside legal protection; this is likely the most intact Caribbean mangrove ecosystem and an important resource for coastal protection, fish nurseries, and wildlife habitat. Even the largest watersheds with the most agricultural land uses have a strong presence of forests, mangroves, and wetlands to buffer and filter runoff. This landscape could change with Cuba's gradual reopening to foreign investment and growing popularity among tourists--trends that have devastated natural ecosystems throughout the Caribbean. Cuba is uniquely positioned to avoid and reverse ecosystem collapse if discontinuities between geopolitical and ecosystem functional units are addressed, if protection and conservation of endemic species and ecosystems services accompany new development, and if a sound ecological-restoration plan is enacted. [ABSTRACT FROM AUTHOR]

Benthic communities at Cayo Levisa coral reef, northwest of Cuba were evaluated in October 2002 and October 2003. Sampling stations were defined in 4 biotopes (2 to 25m deep). The dominant morphotype were foliaceous and calcareous algae, which covered up to 60% of substrate in some areas. Ten species of coral were dominant and their density was higher than sponges and gorgonians in all biotopes. In shallow zones, coral density was higher than in deeper zones and live coral cover was between 30 and 40%. Mean coral diameter oscillated between 20 and 30cm. Less than 3% of the coral, colonies showed signs of disease. The most common diseases was white plague. In 2002, 50-70% of coral colonies in deeper biotopes were bleached. The most affected species were Agaricia agaricites, Montastraea annularis y Siderastraea sidereal. These results are the first quantitative data about the benthic communities at Cayo Levisa´s reefs and they will be useful for future environmental impact assessments in the reefs and for its conservation. [ABSTRACT FROM AUTHOR]

Located in the northwest region of Cuba, Cayo Levisa is the only key in the archipelago "Los Colorados" with tourist installations and where contemplative diving services are offered. Diving is done in costal reefs between 5 and 30m deep, principally in rocky planes with corals and gorgonians, spur and groove and in wall zones. Tables and graphics that show morphological and biological characteristics of the 7 most used diving spots and dominant species of coral and fish in the reefs in 2003 are presented. Sponges and gorgonians were most abundant in the spot localized at the west of the key. Fourteen species of corals were dominant in the reef and coral cover and colony size were bigger in the shallower diving spot. The reefs were dominated by 10 species of fish and the absence of groupers and snappers was significant. [ABSTRACT FROM AUTHOR]

The coastal zone used for contemplative diving at Cayo Levisa, archipelago Los Canarreos, Cuba, is included in the National System of Protected Areas because of its natural values including the not yet studied extent of its coral reefs area. The objectives of this study were to identify and characterize the spatial distribution of the dominant biotopes as well as mapping a list of the most representative species of the reef. Samplings were done between Oct 2002 and Oct 2003. The presence of mangroves and seagrass beds is typical in the area. Inside the coral reefs there are small reef lagoons, plateau (with or without Acropora palmate crest), rocky planes (with a few or very abundant corals), spur and groove that finish by abrupt vertical wall. 71 species of algae, 37 of sponges, 17 of gorgonians, 42 of corals and 77 of fish were identified. Excessive and indiscriminate fishing and the use of anchors are the negatives impacts affecting in a greater degree, the quality and the health of the coral reef ecosystem in the study area. [ABSTRACT FROM AUTHOR]

Coral reef habitats surrounding Cuba include relatively healthy, well-developed shallow and mesophotic (30–150 m) scleractinian communities at the cross-currents of the Tropical Western Atlantic (TWA). However, Cuba's coral communities are not immune to the declines observed throughout the TWA, and there is limited information available regarding genetic connectivity, diversity, and structure among these populations. This represents an immense gap in our understanding of coral ecology and population dynamics at both local and regional scales. To address this gap, we evaluated the population genetic structure of the coral Montastraea cavernosa across eight reef sites surrounding Cuba. Colonies were genotyped using nine microsatellite markers and > 9,000 single nucleotide polymorphism (SNP) markers generated using the 2bRAD approach to assess fine-scale genetic structure across these sites. Both the microsatellite and SNP analyses identified patterns of genetic differentiation among sample populations. While the microsatellite analyses did not identify significant genetic structure across the seven shallow M. cavernosa sampling sites, the SNP analyses revealed significant pairwise population differentiation, suggesting that differentiation is greater between eastern and western sites. This study provides insight into methodological differences between microsatellite and SNP markers including potential trade-offs between marker-specific biases, sample size, sequencing costs, and the ability to resolve subtle patterns of population genetic structure. Furthermore, this study suggests that locations in western Cuba may play important roles in this species' regional metapopulation dynamics and therefore may merit incorporation into developing international management efforts in addition to the local management the sites receive. [ABSTRACT FROM AUTHOR]

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. • The reefs close to watersheds showed a decline in water quality in the NW of Cuba. • The structure of the octocoral assemblages varied due to fecal organic pollution. • The richness, diversity and octocoral density decreased due to organic pollution. • P. kuekenthali was more tolerant to organic pollution than other octocoral species. [ABSTRACT FROM AUTHOR]

The Benthic community of coral reef in Ensenada de Corrientes, southeast of Peninsula of Guanahacabibes, Cuba was evaluated in June 2001. Nine sampling stations representing the biotopes of spur and groove, rocky plane and patch reef (3-12 m deep) were placed. In each station 25 sampling units (1m and 25 x 25 cm frame) were taken. The statistical differences among biotopes were analyzed by unifactorial ANOVA. The biotopes of coral head and spur and groove had mean values of coral cover (20%) higher than in the rocky plane. The filamentous algae cover is over 60% in the plane and the foliose algae (genus Dictyota and Lobophora) cover almost 50% of the substrate in coral head and spur and groove. The density of sponges and gorgonians varied between 0.5-1 col/m² in the reef. The sponges were more abundant in the spur and groove and coral head, and the gorgonians in the plane. The most abundant genus of coral in the reef were Agaricia and Siderastraea, with density over 1.5 col/m² and Montastraea and Porites with density between 0.5 and 1 col/m². Of the total coral colonies counted in the reef, from 15 to 25% showed sings of old or recent mortality but the average of affected surface was less than 10%. These percentages tend to grow in the spur and groove and the most affected species were Siderastraea siderea, Montastraea spp. and Diploria strigosa. The most common diseases were the black band and the dark spots. [ABSTRACT FROM AUTHOR]

The diving zone of Punta Frances is situated in the South West of the Isle of Youth, and is proposed as National Park in the Cuban National System of Protected Areas. The Park has a marine extension of 5.15 km² and includes a coral reef with high diversity of species and biotopes. The study done in 2001 and 2002 allowed us to identify 42 species of algae, 3 fanergamas, 29 sponges, 21 gorgonians, 35 corals and 79 fish. The most representative habitats from the coast line to 25 m depth were: sand bottom with or without seagrass bead; shallow patch reef; Acropora crest; carbonate hardbottom with isolated coral and gorgonians with a slope (veril); deep patch reef and spur and groove close to the wall. In general a healthy reef was found, although some indicators, as a high macroalgae and cyans cover with damaging effect on benthonic sesil organisms and a scarcity of big herbivorous and carnivorous fish alerted about potential disturbances in the reef. [ABSTRACT FROM AUTHOR]