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Discovery of a late Pleistocene (∼13,300 cal BP) reef-building coral species (Pocillopora damicornis) at the prehistoric Huaca Prieta settlement in Peru raises the question of its origin. Did it arrive in northern Peru from tropical Ecuador via larval dispersal in south-flowing El Niño currents or over land by human trading? The Holocene distribution of Pocillopora in the eastern Pacific extends as far south as southern Ecuador and possibly northern Peru. The marine climate during the late Pleistocene was cooler and likely limited the occurrence of corals at today's latitudinal range. This suggests that overland or onshore transport was the most likely means of a southerly introduction, thus supporting interpretative models of early human movement along the Pacific coast of South America. [ABSTRACT FROM AUTHOR]

Abstract: Corals in the Arabian/Persian Gulf endure summer temperatures of up to 36°C, making them ideal subjects to study the mechanisms underlying thermal tolerance. Unexpectedly, we found the “generalist” Symbiodinium clade C3 to be the prevalent symbiont among seven coral species from Abu Dhabi (UAE) waters. Moreover, C3 represented the only dominant symbiont type in Porites spp. from this region. The “thermotolerant” symbionts D1a and C15 were not encountered, indicating that the association with these symbionts cannot be the sole reason for the heat tolerance of Gulf corals. The association of Porites lobata with specific symbiont types (C3 vs. C15) in samples from habitats with very different temperature regimes (Abu Dhabi vs. Fiji) remained unaffected by laboratory culture. During temperature stress experiments specimens from both locations strongly downregulated green fluorescent protein (GFP)-like pigments. However, the Abu Dhabi samples were less prone to bleaching and showed lower mortality. [Copyright &y& Elsevier]

The diversity, abundance and distribution of reef fish are related to heterogeneity and physical complexity of benthic habitat. However, the field effort required to evaluate these aspects of the benthos in situ, at the scale of entire reefscapes, is greatly constrained by logistical and resource limitations. With moderate ground truthing, both substratum type and seabed topography are amenable to monitoring using satellite data. Here, remote sensing imagery was used to resolve the bathymetry and benthic character of a reef system in Diego Garcia (British Indian Ocean Territory). Replicate fish counts were made at seven measurement stations across the study area using visual census. Monte Carlo simulation revealed that species richness and abundance of several guilds and size groupings of reef fish appraised in situ were correlated with the satellitederived seabed parameters over areas of seafloor as large as 5,030 m2. The study suggests that satellite remote sensing is capable of predicting habitat complexity at a scale relevant to fish. Furthermore, as larger size classes of fish were better predicted with the satellite habitat complexity data, this technique could be used to predict fish stocks and identify potential sites for marine protected areas where intensive field surveys are not practical. [ABSTRACT FROM AUTHOR]

This paper describes the geomorphology of the northern, relict, portion of the Florida reef tract that extends along the southeast Florida (USA) continental coast northward to latitude N26° 43.1′. The descriptions are based on high-resolution Laser Airborne Depth Sounding bathymetric data along Miami-Dade, Broward, and Palm Beach Counties as well as chirp subbottom-profiles and reef cores. The SE Florida continental reef tract consists of relict Holocene reefs and lithified sand ridges that apparently formed during backstepping of the reefs in response to sea-level rise. The outer reef is a linear structure that is more or less continuous from Miami-Dade to Palm Beach County and as such is one of the longest continuous reef structures in the western Atlantic. Its relation with the modern Florida Keys reef tract cannot be clearly resolved without further study. The outer reef may be equivalent to the shelf-edge reefs of the Florida Keys. It is broken by reef gaps that likely represent paleo-river channels cross-cutting the underlying Pleistocene substrate. The upward growth of the outer reef ceased approximately 8,000 cal BP (calibrated 14C age before present). A middle reef may represent a remnant shoreface with continuous reef framework. Its growth ceased approximately 3,700 cal BP. An inner reef of Acropora palmata framework is perched on shoreline deposits. It ceased growth approximately 6,000 cal BP. Several nearshore ridges consist of coquina and carbonate/quartz sandstone. [ABSTRACT FROM AUTHOR]

This paper assesses damage to diving sites off Hurghada and Safaga, Egypt, and examines management responses and options. Data were obtained using the line-intercept-transect method. Using general field observations, a control site comparison and a historical comparison, it was found that the four diving sites studied suffered varying degrees of physical damage and needed management attention. Some transect locations had experienced severe physical damage while others had escaped damage. The most obvious difference between the control site and the four damaged sites (at both 4 and 8 m depths) was the consistently high percentage cover of hard coral (especially Acropora coral) and low percentage cover of soft corals among all transects at the Giftun Canal control site. Total algae percentages were also consistently higher at impacted transect sites versus the control site. From a historical perspective, at the Small Giftun site from 1987 to 1996, percentage hard coral cover decreased by 43% and algal cover increased over fourfold. If the diving tourism industry is to sustain itself in the Egyptian Red Sea, every management effort must be made to minimise controllable sources of stress on the coral reef system. Dive site management programme options, based on peer-reviewed carrying capacity research and stakeholder involvement, are reviewed. [ABSTRACT FROM AUTHOR]

Predicted increases in seawater temperatures accelerate coral reef decline due to mortality by heat-driven coral bleaching. Alteration of the natural nutrient environment of reef corals reduces tolerance of corals to heat and light stress and thus will exacerbate impacts of global warming on reefs. Still, many reefs demonstrate remarkable regeneration from past stress events. This paper investigates the effects of sea surface temperature (SST) and water column productivity on recovery of coral reefs. In 71 Indo-Pacific sites, coral cover changes over the past 1-3 decades correlated negative-exponentially with mean SST, chlorophyll a, and SST rise. At six monitoring sites (Persian/Arabian Gulf, Red Sea, northern and southern Galápagos, Easter Island, Panama), over half of all corals were <31 years, implying that measured environmental variables indeed shaped populations and community. An Indo-Pacific-wide model suggests reefs in the northwest and central Indian Ocean, as well as the central west Pacific, are at highest risk of degradation, and those at high latitudes the least. The model pinpoints regions where coral reefs presently have the best chances for survival. However, reefs best buffered against temperature and nutrient effects are those that current studies suggest to be most at peril from future ocean acidification. [ABSTRACT FROM AUTHOR]

The article discusses research which found that the raised coral reefs in Larak, Iran suggest the dominance of Acropora in the reefs of the Persian Gulf since the Pleistocene era.

Light traps were used to describe the vertical distribution of late larval stages of reef fishes in the San Blas Archipelago during threesuccessive new moon periods. Traps were deployed in the lagoon and at an exposed site on the outer reef edge. At each site, two traps were anchored at the surface and two traps just above the bottom. Most families of reef fishes that were abundant in catches displayed clear patterns of depth preference. The larvae of gerrids, pomacentrids andlutjanids were predominantly captured in shallow traps, while gobiids, labrids, apogonids and blenniids were usually collected in deep traps. Studies that used lights to aggregate and collect larval fishes display marked differences in the composition of catches between the Great Barrier Reef (GBR) and the Caribbean. In order to determine whether such results were due to biases inherent in different sampling methods, or to locality-specific patterns of larval behaviour, we simultaneously deployed light traps and dip-netting around lights during three new moons in the San Blas Archipelago. We found that these sampling techniques collected differing components of the larval fish assemblage from the same water mass. However, there remains good evidence for the existence of locality-specific responses to light in older larval stages, suggesting that broad generalisations about patterns and causes of vertical distributions may be difficult to achieve. [ABSTRACT FROM AUTHOR]

In this study we characterized the prokaryotic microbiota associatedwith the reef-building coral Montastraea franksi in a culture-independent manner by sequencing 16S rDNAs. The majority of the bacteria identified by this method were novel species and belonged to a wide variety of microbial groups, with cyanobacteria and -proteobacteria being the most abundant. In contrast, the bacteria cultured from the same M. franksi samples were closely related to previously described bacteria and consisted mostly of -proteobacteria. These results show that the microbial diversity associated with corals can be greatly underestimated when relying exclusively on culture-based methods. Our analyses also showed that one -proteobacteria specieswas present in all M. franksi samples isolated from five reefs separated by up to 10 km. This finding is suggestive of a specific microbe-coral association. [ABSTRACT FROM AUTHOR]

Provides a corrected reprint of the research article 'Corals in a Non-Reef Setting in the Southern Arabian Gulf (Dubai, UAE): Fauna and Community Structure in Response to Recurring Mass Mortality,' by B. Riegl, previously published in the volume 18, 1999 edition of the periodical 'Coral Reefs.'

Dynamite damage was investigated on 60 reefs in the Egyptian Red Sea. 65% of the investigated reefs had signs of dynamite damage, mostly in leeward areas (58%). Significant changes in coral and fish community composition within dynamited sites were observed. Coral cover decreased, the amount of bare substratum and rubble increased, fish communities in dynamited areas suffered a decrease in species richness andabundance. Due to a stable pattern of coral community differentiation on northern Red Sea reefs (windward Acropora, leeward Porites) mostdamage is on near-climax Porites reef slopes or Porites carpets. Natural regeneration of such communities is likely to be very slow, possibly taking several hundred years. Rehabilitation would be difficult since coral transplants would have to mimic the previously existing community. [ABSTRACT FROM AUTHOR]

Despite differences in reef growth between the Arabian Gulf and the Red Sea, a common distinctive pattern of polygonal sills surrounding ponded depressions consistently occurs in shallow water. Viewed from a satellite, these seafloors are reticulated and maze like. Despite little current rainfall, this patterning is best explained by karst dissolution of limestone during periods of lower sea level. This is a paradox since such fine-scale karstification is confined to areas with considerably more precipitation than currently observed in Arabia. We resolve this apparent contradiction by developing a Pleistocene-Holocene chronology of sea level and climate for the Red Sea and Arabian Gulf, and through the use of pattern analysis and computer simulation, reveal the mechanism of formation for these structures. We demonstrate that this patterning can be taken as a Quaternary signature of paleohumidity in the now hyperarid Red Sea and Arabian Gulf. [ABSTRACT FROM AUTHOR]

The reef communities of the Florida coral reef tract play a major role in supporting the regional economy but are threatened by increased exploitation and environmental factors. Coral reef ecosystem services are vital to the economy of SE Florida where revenue and jobs depend on the status of reef resources. Here, we used an extensive, reef monitoring database collected by the Florida Reef Resilience (FRRP, 2003-2011) and the Atlantic and Gulf Rapid Reef Assessment (AGRRA, 1997-2011) programs to evaluate percent recent mortality (PRM) as a robust ecological indicator of coral colony and coral reef status. PRM, the proportion of a coral colony that has experienced recent tissue mortality so that corallite structures in the non-living parts of the coral are still intact and identifiable to species, can be attributed to disturbances taking place within days to a few months preceding the surveys. Based on data from >50,000 colonies from 11 coral species and nearly 1400 sites, we propose a benchmark level of <1% PRM and <5% prevalence of partial mortality for Florida reefs during periods of background, low-stress environmental conditions. PRM levels >1.0% and prevalence levels >5% can be used as early warning indicators of degrading conditions. Average PRM values >2% are indicative of increasingly stressful conditions as those experienced during temperature anomalies and major hurricanes. Finally, PRM values considerably >2% are reflective of significantly stressful conditions and warning signals of potential major coral mortality as evidenced by mean PRM levels of >10% recorded in Florida as a consequence of the 2010 extreme cold-water event. PRM and prevalence values from Florida reefs compared favorably with those recorded in the Caribbean and the Mesoamerican region where a benchmark of 2% for background levels of PRM under low-level, chronic stress was proposed. The status of this indicator can be easily communicated to stakeholders and will benefit managers by providing: (1) a baseline to assess the status of coral populations; and (2) early-warning indicators of unfavorable conditions that may trigger management actions such as temporary closures or the establishment of more permanent protection such as MPAs. [ABSTRACT FROM AUTHOR]