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In recent years, coral populations in the western Atlantic have undergone widespread declines from climate change, anthropogenic stressors, and infectious disease outbreaks. The pillar coral, Dendrogyra cylindrus, has been one of the most affected species, prompting its listing as threatened under the United States Endangered Species Act in 2014 and critically endangered under the IUCN Red List in 2022. However, due to its natural rarity, it is particularly difficult to study using conventional long-term monitoring studies or less common paleontological investigations. Here, we document for the first time, the multi-century persistence of D. cylindrus on high-latitude nearshore reefs off southeast Florida during the late Holocene. Using high-precision uranium–thorium (U-Th) dating, we constrain the ages of well-preserved subfossil D. cylindrus colonies recovered from newly described coral death assemblages. We also describe specific morphological characteristics and taphonomic indicators reflecting their unique depositional environment. Our findings demonstrate long-term persistence of D. cylindrus in southeast Florida, despite geographical isolation and historical rarity in the region. [ABSTRACT FROM AUTHOR]

Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. B Correction to: Coral Reefs b https://doi.org/10.1007/s00338-023-02387-3 The original article has been corrected: the affiliation details for Anton Oleinik were incorrectly given as 'U.S. Geological Survey St. Petersburg Coastal and Marine, Science Center, St. Petersburg, FL 33701, USA' but should have been 'Department of Geosciences, Florida Atlantic University, Boca Raton, FL 33431, USA'. [Extracted from the article]

Background: The threespot damselfish, Stegastes planifrons (Cuvier), is important in mediating interactions among corals, algae, and herbivores on Caribbean coral reefs. The preferred microhabitat of S. planifrons is thickets of the branching staghorn coral Acropora cervicornis. Within the past few decades, mass mortality of A. cervicornis from white-band disease and other factors has rendered this coral a minor ecological component throughout most of its range. Methodology/Principal Findings: Survey data from Jamaica (heavily fished), Florida and the Bahamas (moderately fished), the Cayman Islands (lightly to moderately fished), and Belize (lightly fished) indicate that distributional patterns of S. planifrons are positively correlated with live coral cover and topographic complexity. Our results suggest that speciesspecific microhabitat preferences and the availability of topographically complex microhabitats are more important than the abundance of predatory fish as proximal controls on S. planifrons distribution and abundance. Conclusions/Significance: The loss of the primary microhabitat of S. planifrons-A. cervicornis-has forced a shift in the distribution and recruitment of these damselfish onto remaining high-structured corals, especially the Montastraea annularis species complex, affecting coral mortality and algal dynamics throughout the Caribbean. [ABSTRACT FROM AUTHOR]

Some authors argue that overfishing is an important reason that reef corals have declined in recent decades. Their reasoning is that overfishing removes herbivores, releasing macroalgae to overgrow and kill the corals. The evidence suggests, however, that global climate change and emergent marine diseases make a far greater contribution to coral mortality, and that macroalgae generally grow on the exposed skeletal surfaces of corals that are already dead. Macroalgal dominance, therefore, is an effect rather than a cause of coral mortality. Marine protected areas (MPAs), which are usually established to protect stocks of reef fish, foster populations of herbivorous fish under at least some circumstances. Increased herbivory can reduce algal cover, potentially accelerating the recovery of coral populations inside MPAs; however, establishing MPAs will have only a limited impact on coral recovery unless policymakers confront the accelerating negative effects of the global-scale sources of coral mortality. [ABSTRACT FROM AUTHOR]

Many Caribbean reefs have experienced a phase-shift in community structure, the principle features being a decline in coral cover and an increase in macroalgal biomass. However, one Jamaican reef—Dairy Bull on the north shore near Discovery Bay—is once again dominated by scleractinian corals and several key species have returned. Living coral cover at 6-8 m depth at Dairy Bull has doubled over the past 9 years and is now ∼54%. The absolute cover of Acropora cervicornis was <1% in 1995, but increased to ∼11% by January 2004. During this time the cover of macroalgae decreased by 90%, from 45 to 6%. We speculate that long-lived colonies of Montastraea annularis may have facilitated the recovery of this reef by providing structural refugia. [ABSTRACT FROM AUTHOR]

Bessell-Browne et al. (2017) published a paper where they proposed using mounding Porites spp. corals from Western Australia as a bio-indicator of sediment stress on coral reefs. They based their interpretations on results obtained during the monitoring of a capital dredging program coupled with laboratory sediment dousing experiments. They stated that because these Porites species generate mucous sheets in response to sediment loading, they could be used as an early warning indicator of sediment stress adjacent to sensitive coral resources. While their results are compelling, there are several confounding issues that arise questioning the wide-scale application and use of Porites spp. corals as bio-indicators. Using examples of Porites species from both the Indo-Pacific and Caribbean, I detail a number of contrary results that reveal that mucous sheet development is most likely attributed to mucus production and subsequent mucus sloughing that are cued to an endogenous lunar cycle (approximately 28 days in duration) and not necessarily as a direct strategy to protect the coral tissue from harm due to sediment stress. While the mucous sheet becomes fouled with sediment during the cycle, the amount of sediment observed may not be a response to the level of sediment stress, but where in the 28-day cycle the mucous sheet is observed. Thus, depending on when you observe the colony (early, middle or late in the 28-day cycle) the level of purported sediment impact would be highly variable. This variability leads to an unacceptably high rate of both Type-I and Type-II statistical errors. Because of the cyclical, endogenous nature of mucus production in many Porites spp., extreme caution should be employed before using these species to infer the level of sediment impact associated with dredging projects or their use as a predictive tool of sediment stress on coral reefs. [ABSTRACT FROM AUTHOR]

Deals with coral bleaching in Belize. Mass mortality of scleractinian corals on lagoonal reefs; Response to high temperature and/or high incident solar radiation; Dominant space-occupier on lagoonal reefs; Degradation of coral reef ecosystems.

Global mean sea level (GMSL) reconstructions from past interglacial periods help us understand the sensitivity of ice sheets to a warming climate. In this study, we focus on Marine Isotope Stage 5a (MIS 5a), a warm period that peaked 82,000 years ago and for which current GMSL estimates remain widely uncertain (ranging from −28 m to +1 m). Here we reconstruct relative sea level (RSL) based on an extensive and exquisitely preserved fossil coral reef at Cave Hill, Barbados, which has not been examined before. We dated one coral sample (Acropora palmata) from this outcrop using U-series dating and obtained a closed system age of 82.5 ± 0.4 ka and an open system age of 83.3 ± 0.7 ka (2 σ), which confirm that the reef formed during MIS 5a. We determine RSL based on the elevation of 222 fossil corals within the outcrop from three species (Acropora palmata , Siderastrea radians , Favia fragum). The coral elevations are combined using Bayesian inference to obtain a posterior common RSL, with present-day water depths of each species as priors. We use our inference scheme and synthetic datasets to explore the number and species of corals needed for a robust RSL estimate and find that if approximately 5 corals are sampled, roughly half of which have a narrow living depth range (0 to ∼10 m), the accuracy and precision of the inferred RSL is around 1.5 m. This value improves to less than 0.5 m if more corals (approximately 20) are sampled, especially if these have narrow living depth ranges. These tests can guide future coral sampling at other outcrops. After inferring RSL from the real coral elevations, we correct it for long-term uplift, using the elevation of the adjacent MIS 5e sea level outcrop to calculate an uplift rate of 0.522 ± 0.036 m/kyr (1 σ), and for glacial isostatic adjustment. We find that GMSL most likely peaked at −22.3 m relative to present GMSL (−32.5 m to −10.7 m, 95% credible interval). This work provides a new estimate for MIS 5a GMSL that is lower than results from most previous studies, and confirms sequentially decreasing GMSL during the MIS 5e, 5c, and 5a precessional insolation peaks, indicating increased ice sheet growth and cooling into the ice age following the peak interglacial MIS 5e. • We reconstruct global mean sea level (GMSL) for MIS 5a using a fossil coral reef at Cave Hill, Barbados. • We dated one coral (Acropora palmata) from this outcrop to confirm its MIS 5a age. • We use Bayesian inference to determine relative sea level (RSL) based on 222 fossil coral elevations. • MIS 5a GMSL was most likely −22.3 m relative to present (−32.5 m to −10.7 m, 95% credible interval). • Our MIS 5a GMSL is consistent with decreasing GMSL over the MIS 5e, 5c, and 5a insolation peaks. [ABSTRACT FROM AUTHOR]