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Anthropogenic and environmental stressors damage the structure and function of coral reefs. Monitoring data is important because it allows scientists to detect changes that are of interest for managers and policymakers. This study aims to examine the benthic component (abiotic and biotic) and determine coral life-history composition at different reef types (atoll and fringing) and regions (Wangi-Wangi and Kaledupa) in the Wakatobi National Park (WNP), Southeast Sulawesi, Indonesia. We examine the data using life-history traits in regard to group species and describe community composition. Kaledupa fringing reef had 46% hard coral cover, which was the highest hard coral cover in our study. There was no significant difference in hard coral and soft coral cover between regions within WNP. Reef type, however, showed significant differences in hard coral and soft coral cover, as well as sand, rubble, and rock. The families Acroporidae and Poritidae were the most dominant across all sites and reef types in WNP. The life-history classification showed competitive and stress-tolerant coral covers were greatest on fringing reefs. Our findings provide information regarding coral reef benthic community composition and distribution across regions and reef types in WNP, which can aid in coral reef conservation. [ABSTRACT FROM AUTHOR]

As thermal bleaching events are expected to increase in frequency for many coral reefs around the world, the 2015 bleaching event in the Main Hawaiian Islands was only the second ever recorded archipelago-wide bleaching event. Understanding baseline changes in the reefs after a bleaching event allows local managers to make informed decisions to support recovery of reefs. Using benthic imagery taken just days after the peak of bleaching and at 6 month and 1.5-year intervals, this project followed five of Maui’s most abundant coral species through a post bleaching time series analysis. Beginning with an assessment of bleaching severity, the fate of individual corals on two Maui reefs was tracked to understand if corals recovered, suffered partial mortality, or suffered full mortality. Corals from the Olowalu site showed a trend toward reduced size class of corals after the bleaching event while corals from the Kahekili site showed a trend toward larger size class of corals after the bleaching event. Overall at both sites, corals that bleached less severely recovered more healthy tissue between 2015 and 2017.

Coral reefs worldwide are threatened by thermally induced bleaching. In 2015, the National Oceanic and Atmospheric Administration declared the third recorded global thermal bleaching event during which Hawaiian coral reefs were severely impacted. In order to understand how Hawaiian reefs responded to this event, data were examined from benthic imagery from three sites on leeward Maui that represent a gradient of management. Data were extracted from composite 100m2 photomosaic images of reef benthos, which were constructed for July 2014 (prior to bleaching) and June 2016 (following bleaching). In each photomosaic, colonies of mounding Porites (P. lobata, P. evermanni, and P. lutea) were individually outlined and numbered in order to compare colony size class distribution before and after the 2015 bleaching event. Overall, the mounding Porites communities of leeward Maui reefs experienced a shift towards smaller size classes from 2014 to 2016. Changes in size, quantified in both absolute and percent changes, were not correlated with management regimes. These data suggest that management of local stressors may not be sufficient to mitigate the immediate effects of thermal bleaching events on coral reefs.

In their recent letter, Madin et al. (2016) dispute our findings in Muir et al. (2015a) that reduced levels of light during winter confine staghorn corals to shallower depths at higher latitudes and will ultimately limit their scope for latitudinal expansion as oceans warm. We based our conclusions on a rich global dataset analysed using two types of analyses: polynomial quantile regression models and species distribution models. Madin and colleagues’ reanalysis of our data focuses only on the quantile regression model, and in our view, provides no convincing quantitative evidence in support of their proposition that most species exhibit either no trend or a reverse trend to the one we described.

Dendrophyllia ramea is a poorly known arborescent scleractinian coral, whose worldwide distribution is limited to the southern part of the Mediterranean basin, and to the Atlantic Ocean between Macaronesia and Gulf of Cadiz. The geographical distribution and abundance of D. ramea were herein updated, considering a total of 19 records, seven of which have never previously been reported in scientific papers.Between 2010 and 2017, five Remotely Operative Vehicle surveys carried out along the Sicilian coast recorded 89 colonies. No exhaustive data on density and ecology of this species have been published to date. Data for two areas off the north‐eastern Sicilian waters (Aeolian Island and Gulf of Patti) are reported, including the species' bathymetric distribution, abundance, population density, colony morphometry, population size structure and surrounding habitat description.Size structure and density of D. ramea populations were compared with lost fishing gear density. Around the Aeolian Islands, where little lost fishing gear was observed, the D. ramea population was denser compared with the populations at two sites within the Gulf of Patti, where a greater amount of lost fishing gear was observed. The analysis of D. ramea size classes (single corallite, 2–5 polyps, >5 polyps) at different sites showed that impact varied with fishing gear typology: while lines damage the branches of larger colonies, nets can completely remove them.The limited distribution of D. ramea in some areas also makes this species very vulnerable to impacts such as changes in the chemical–physical characteristics and circulation of sea water. Dendrophyllia ramea is classified as 'Vulnerable' according to the Mediterranean IUCN Red List, and it is listed in the Barcelona Convention (Annex B). Data on the distribution of D. ramea allows us to review the species' classification and propose that its status be changed to 'Endangered'. [ABSTRACT FROM AUTHOR]

Colonies of coral with morphology similar to that of Oculina patagonica de Angelis, 1908 were found in the National Park Veracruz Reef System (NPVRS) along the coast of Veracruz, Mexico in the southern Gulf of Mexico. The identity of these colonies as O. patagonica was confirmed by morphological and molecular analyses. Here, we document the first records of O. patagonica in the Gulf of Mexico. This species is native to the Mediterranean Sea, and could have been accidentally introduced to the Gulf of Mexico through ballast water from ships. In the NPVRS, poor environmental conditions such as polluted waters with high sedimentation, and the capability of O. patagonica to adapt could have facilitated the establishment of this species in the Gulf.

Colonies of coral with morphology similar to that of Oculina patagonica de Angelis, 1908 were found in the National Park Veracruz Reef System (NPVRS) along the coast of Veracruz, Mexico in the southern Gulf of Mexico. The identity of these colonies as O. patagonica was confirmed by morphological and molecular analyses. Here, we document the first records of O. patagonica in the Gulf of Mexico. This species is native to the Mediterranean Sea, and could have been accidentally introduced to the Gulf of Mexico through ballast water from ships. In the NPVRS, poor environmental conditions such as polluted waters with high sedimentation, and the capability of O. patagonica to adapt could have facilitated the establishment of this species in the Gulf. [ABSTRACT FROM AUTHOR]

In their recent letter, Madin et al. (2016) dispute our findings in Muir et al. (2015a) that reduced levels of light during winter confine staghorn corals to shallower depths at higher latitudes and will ultimately limit their scope for latitudinal expansion as oceans warm. We based our conclusions on a rich global dataset analysed using two types of analyses: polynomial quantile regression models and species distribution models. Madin and colleagues’ reanalysis of our data focuses only on the quantile regression model, and in our view, provides no convincing quantitative evidence in support of their proposition that most species exhibit either no trend or a reverse trend to the one we described.

Many species have experienced recent range expansions due to human-mediated processes, such as the unintentional transport on ships or plastic waste and ocean warming, which facilitates many tropical species to tolerate living beyond their normal limit of distribution, with a potential impact on autochthonous assemblages. In September 2008, three colonies of the fire coral Millepora sp. (Cnidaria: Hydrozoa) were found on the southeastern coast of Tenerife (Canary Islands), though this species had been previously described to have a circumtropical distribution with Cape Verde Islands as its northern limit of distribution in the eastern Atlantic. The aim of this study was to determine the origin of these new colonies in the Canary Islands (11°N of its previously known northernmost limit of distribution) using variation in the cytochrome oxidase subunit I (COI) gene as a molecular marker. In order to do that, Millepora samples from Tenerife and Cape Verde Islands were collected for molecular analyses, and COI sequences from Caribbean samples listed in GenBank were also included in the analysis. Our results showed that all the specimens from Tenerife were genetically identical, suggesting that the colonization of the Canary Islands was the result of a very recent and strong founder effect. The nucleotide sequences of the samples from the Cape Verde and the Canary Islands were closer to the Caribbean than between themselves, pointing to the Caribbean population as the source population for both archipelagos, through independent founder events. The fact that Millepora sp. arrived to Cape Verde long before arriving to the Canaries (pleistocene fossils have been found in that archipelago) suggests that the habitat requirements for this species did not exist before in the Canarian archipelago. Therefore, the rising seawater temperatures recently registered in the Canary Islands could have facilitated the settlement of reef-forming corals drifting across the two basins of the Atlantic. [ABSTRACT FROM AUTHOR]

Coral communities in China's Great Bay Area (GBA) have experienced severe degradation, but only limited information is available about their community structure. We surveyed 20 sites across three regions (Daya Bay, Dapeng Bay, Wanshan Islands) in GBA to provide an updated baseline of these urban coral communities. Live coral cover varied substantially, with the lowest values (<2 %) found inside the highly urbanized Daya Bay, and highest values (40–47 %) from offshore islands that are less affected by human activities. The two sites with the lowest live coral cover had a high percentage of dead coral. Five groups of coral communities could be identified, with most of them characterized by dominance of massive and encrusting coral species. Both coral cover and generic richness were negatively correlated with dissolved inorganic nitrogen in the water column, indicating that nutrient pollution could potentially constrain the development of these urban coral communities. • We aimed to provide a baseline of coral communities along the coasts of Guangdong, China. • We surveyed 20 sites across Daya Bay, Dapeng Bay, and Wanshan Islands. • Live coral cover varied substantially from 1.3 % to 46.5 %. • Most sites were dominated by massive and encrusting coral species. • Coral cover and generic richness were negatively correlated with dissolved inorganic nitrogen. [ABSTRACT FROM AUTHOR]

Efforts to map coral reef ecosystems in the Hawaiian Archipelago using optical imagery have revealed the presence of numerous scleractinian, zoothanthellate coral reefs at depths of 30–130+ m, most of which were previously undiscovered. Such coral reefs and their associated communities have been recently defined as mesophotic coral ecosystems (MCEs). Several types of MCEs are found in Hawai‘i, each of which dominates a different depth range and is characterized by a unique pattern of coral community structure and colony morphology. Although MCEs are documented near both ends of the archipelago and on many of the islands in between, the maximum depth and prevalence of MCEs in Hawai‘i were found to decline with increasing latitude. The Main Hawaiian Islands (MHI) had significantly deeper and greater percentages of scleractinian coral, and peaks in cover of both scleractinian corals and macroalgae occurred within depth bins 20 m deeper than in the Northwestern Hawaiian Islands (NWHI). Across the archipelago, as depth increased the combined percentage of living cover of mega benthic taxa declined sharply with increasing depth below 70 m, despite the widespread availability of hard substrate. [ABSTRACT FROM AUTHOR]

We surveyed 41 sites to provide an updated baseline of Hong Kong coral communities. Five community types were identified, among them the most common one inhabited oceanic waters and dominated by both massive and upward-plating corals. The 41 sites had 2.1–⁠79% coral cover; among them 21 in the eastern waters had >40% coral cover. Corals in several sites showed signs of external bioerosion or bleaching-induced damage. Sites in the southern waters had low coral cover. Both coral cover and generic richness correlated negatively with several water quality parameters including total inorganic nitrogen concentration and turbidity, indicating the development of Hong Kong's coral communities is constrained by water quality parameters. Management actions are proposed to reduce bioerosion, and to monitor sites affected by bleaching. [ABSTRACT FROM AUTHOR]