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Summary: Coral thermal bleaching resilience can be improved by enhancing photosymbiont thermal tolerance via experimental evolution. While successful for some strains, selection under stable temperatures was ineffective at increasing the thermal threshold of an already thermo‐tolerant photosymbiont (Durusdinium trenchii). Corals from environments with fluctuating temperatures tend to have comparatively high heat tolerance. Therefore, we investigated whether exposure to temperature oscillations can raise the upper thermal limit of D. trenchii.We exposed a D. trenchii strain to stable and fluctuating temperature profiles, which varied in oscillation frequency. After 2.1 yr (54–73 generations), we characterised the adaptive responses under the various experimental evolution treatments by constructing thermal performance curves of growth from 21 to 31°C for the heat‐evolved and wild‐type lineages. Additionally, the accumulation of extracellular reactive oxygen species, photophysiology, photosynthesis and respiration rates were assessed under increasing temperatures.Of the fluctuating temperature profiles investigated, selection under the most frequent oscillations (diurnal) induced the greatest widening of D. trenchii's thermal niche. Continuous selection under elevated temperatures induced the only increase in thermal optimum and a degree of generalism.Our findings demonstrate how differing levels of thermal homogeneity during selection drive unique adaptive responses to heat in a coral photosymbiont. [ABSTRACT FROM AUTHOR]

The die‐off of the long‐spined sea urchin Diadema antillarum in the 1980s highlighted its crucial role as a primary grazer in tropical western Atlantic coral reefs. However, natural recovery has been slow, exacerbated by a new die‐off in 2022. Interest in actively restoring D. antillarum populations has grown with the emergence of culture and rearing techniques. Restocking reefs with laboratory‐reared urchins shows potential for enhancing coral reef resilience by reducing algal cover and promoting coral settlement, but success rates vary. Predation and migration contribute to low retention rates, with distinguishing between them is challenging. In this study near Saba, Caribbean Netherlands, we released 200 laboratory‐reared D. antillarum on a reef and monitored for D. antillarum retention and potential D. antillarum predator presence and interaction for 35 days. Only 40% of the urchins were still present on the reef after day one. The Spanish hogfish Bodianus rufus was identified as the primary daytime predator, responsible for nine direct predation events. No nighttime predation was observed, but interaction with a batwing coral crab Carpilius corallinus was noted. These insights can help optimize future restocking attempts and emphasize  the importance of assessing predator presence beforehand. Reefs with high abundances of predators such as Spanish hogfish should be avoided for D antillarum restocking. In addition, before being released, lab‐reared animals should be given time to acclimate to conditions in the wild by being placed in protected in situ cages. Here, they could also grow to larger sizes that are less vulnerable to predation. [ABSTRACT FROM AUTHOR]

According to the prevailing view in literature, two Eocene carbonate platform belts developed on northern and southern margins of the Tethys Ocean. However, Eocene platforms in the Malaguide−Ghomaride Units (Betic-Rifian Arc; Spain and Morocco, respectively) in intermediate position to the classic platform belts have been proposed in recent literature. A number of representative Ypresian to Priabonian stratigraphic sections have been revisited and empowered by new data collected for the scope. Ten lithobiofacies (consisting of limestones rich in Larger Benthic Foraminifera (LBF), algae, and corals) and ten microfacies (based on fossil assemblage and their relative abundance, texture, and fabric) were proposed for this intermediate platform belt in recent literature. The paleoenvironmental reconstruction indicate inner to outer ramps (locally also the upper slope) arranged in two sedimentary sequences rich in LBF and corals. A great development of carbonate seagrass factories in most of the areas in which inner ramps developed has been identified. These factories correspond to a warm-temperate system with warm-water conditions mainly in low latitude settings. Trophic resources proposed in these works suggest oligo- to mesotrophic conditions in inner to mid ramp settings, which only evolve to eutrophic conditions in outer ramp and upper bathyal settings. A comparison of the three belts of carbonate platforms at the western Tethys scale has been performed, providing several important constraints in terms of the recorded time period according to the literature, tectonics, transgressive−regressive trendings, relative abundance of fossils, and paleoenvironmental conditions. The Eocene platforms of the westernmost Tethys show a lacunose geological record registered from upper Ypresian (Cuisian) to Bartonian. It shows an important gap at the upper Ypresian (Cuisian)−Lutetian boundary. LBF remained the primary framework builders elsewhere until the Bartonian age, with zooxanthelle−coral build-ups playing a more significant role in the inner ramps than previously assumed. [ABSTRACT FROM AUTHOR]

In this work, an efficient and real-time person re-identification system based on an affordable hybrid framework was presented. The proposed pipeline consisting of human detecting, tracking and extracting features was developed based on lightweight deep neural models so that they could be computationally accelerated on limited hardware resources devices. A comprehensive and substantial dataset has been established aiming to facilitate the training and evaluation of a surveillance system implemented to monitor individuals in an indoor environment. The proposed processing pipeline was implemented on both low-cost devices as Nvidia Jetson Nano and Google Coral. The experimental results indicated that the system could achieve real-time performance with up to 29 FPS and 0.96 mAP for the person detection algorithm task via edge devices, whereas a comparable accuracy was reached on the proposed feature extraction model with 0.85 mAP. [ABSTRACT FROM AUTHOR]

Coral reef ecosystems are highly threatened and can be extremely sensitive to the effects of climate change. Multiple shark species rely on coral reefs as important habitat and, as such, play a number of significant ecological roles in these ecosystems. How environmental stress impacts routine, site-attached reef shark behavior, remains relatively unexplored. Here, we combine 8 years of acoustic tracking data (2013-2020) from grey reef sharks resident to the remote coral reefs of the Chagos Archipelago in the Central Indian Ocean, with a satellite-based index of coral reef environmental stress exposure. We show that on average across the region, increased stress on the reefs significantly reduces grey reef shark residency, promoting more diffuse space use and increasing time away from shallow forereefs. Importantly, this impact has a lagged effect for up to 16 months. This may have important physiological and conservation consequences for reef sharks, as well as broader implications for reef ecosystem functioning. As climate change is predicted to increase environmental stress on coral reef ecosystems, understanding how site-attached predators respond to stress will be crucial for forecasting the functional significance of altering predator behavior and the potential impacts on conservation for both reef sharks and coral reefs themselves. Environmental stress on coral reefs is increasing. Authors show a stress-related reduction in residency of grey reef sharks on the remote reefs of the Chagos Archipelago, promoting more diffuse space use and increased time away from the shallow forereefs. [ABSTRACT FROM AUTHOR]

The partnership between corals and their intracellular algal symbionts has long been a textbook example of a mutually beneficial association. Here I argue that this view has been made obsolete by a steady accumulation of evidence over the past three decades. The coral–algal relationship is perhaps better viewed as one of domestication — think of it like a cattle farm, in which the coral is the farmer and the algae are the cows. I synthesize old and new evidence in support of this updated view and highlight remaining knowledge gaps, the largest of which continues to be the natural history of algal symbionts. The partnership between corals and their intracellular algal symbionts has long been a textbook example of mutually beneficial association. In this essay, Mikhail Matz argues for an updated view in which the coral acts more as a farmer of algal cells to support its own growth. [ABSTRACT FROM AUTHOR]

Background: Coral reefs experience frequent and severe disturbances that can overwhelm their natural resilience. In such cases, ecological restoration is essential for coral reef recovery. Sexual reproduction has been reported to present the simplest and most cost-effective means for coral reef restoration. However, larval settlement and post-settlement survival represent bottlenecks for coral recruitment in sexual reproduction. While bacteria play a significant role in triggering coral metamorphosis and settlement in many coral species, the underlying molecular mechanisms remain largely unknown. In this study, we employed a transcriptome-level analysis to elucidate the intricate interactions between bacteria and coral larvae that are crucial for the settlement process. Results: High Metabacillus indicus strain cB07 inoculation densities resulted in the successful induction of metamorphosis and settlement of coral Pocillopora damicoris larvae. Compared with controls, inoculated coral larvae exhibited a pronounced increase in the abundance of strain cB07 during metamorphosis and settlement, followed by a significant decrease in total lipid contents during the settled stage. The differentially expressed genes (DEGs) during metamorphosis were significantly enriched in amino acid, protein, fatty acid, and glucose related metabolic pathways. In settled coral larvae induced by strain cB07, there was a significant enrichment of DEGs with essential roles in the establishment of a symbiotic relationship between coral larvae and their symbiotic partners. The photosynthetic efficiency of strain cB07 induced primary polyp holobionts was improved compared to those of the negative controls. In addition, coral primary polyps induced by strain cB07 showed significant improvements in energy storage and survival. Conclusions: Our findings revealed that strain cB07 can promote coral larval settlement and enhance post-settlement survival and fitness. Manipulating coral sexual reproduction with strain cB07 can overcome the current recruitment bottleneck. This innovative approach holds promise for future coral reef restoration efforts. [ABSTRACT FROM AUTHOR]

Adaptation of reef-building corals to global warming depends upon standing heritable variation in tolerance traits upon which selection can act. Yet limited knowledge exists on heat-tolerance variation among conspecific individuals separated by metres to hundreds of kilometres. Here, we performed standardized acute heat-stress assays to quantify the thermal tolerance traits of 709 colonies of Acropora spathulata from 13 reefs spanning 1060 km (9.5° latitude) of the Great Barrier Reef. Thermal thresholds for photochemical efficiency and chlorophyll retention varied considerably among individual colonies both among reefs (approximately 6°C) and within reefs (approximately 3°C). Although tolerance rankings of colonies varied between traits, the most heat-tolerant corals (i.e. top 25% of each trait) were found at virtually all reefs, indicating widespread phenotypic variation. Reef-scale environmental predictors explained 12–62% of trait variation. Corals exposed to high thermal averages and recent thermal stress exhibited the greatest photochemical performance, probably reflecting local adaptation and stress pre-acclimatization, and the lowest chlorophyll retention suggesting stress pre-sensitization. Importantly, heat tolerance relative to local summer temperatures was the greatest on higher latitude reefs suggestive of higher adaptive potential. These results can be used to identify naturally tolerant coral populations and individuals for conservation and restoration applications. [ABSTRACT FROM AUTHOR]

The bacterial pathogen Vibrio coralliilyticus induces severe coral diseases in warming oceans. A study in PLOS Biology reveals that high temperatures activate 2 type VI secretion systems in V. coralliilyticus, enhancing pathogenicity by deploying toxic effectors against competing bacteria and coral cells. The bacterial pathogen Vibrio coralliilyticus induces severe coral diseases in warming oceans. This Primer explores a PLOS Biology study revealing that high temperatures activate two type VI secretion systems in V. coralliilyticus, enhancing pathogenicity by deploying toxic effectors against competing bacteria and coral cells. [ABSTRACT FROM AUTHOR]

The structural architecture of coral reefs is a known predictor of species richness, fish biomass and reef resilience. At a smaller scale, three-dimensional (3D) surface area of corals is a fundamental determinant of physical and biological processes. Quantifying the 3D surface area of corals has applications for a broad range of scientific disciplines, including carbonate production estimates, coral predation studies, and assessments of reef growth. Here, we present morphotaxon-specific conversion metrics to estimate total 3D surface area and projected 2D surface area of individual colonies from simple field measurements of colony maximum diameter. Underwater photogrammetry techniques were used to quantify surface area and estimate conversion metrics. Bayesian models showed strong non-linear (power) relationships between colony maximum diameter and both total 3D surface area and projected 2D surface area for 13 out of 15 morphotaxa. This study presents a highly resolved and efficient method for obtaining critical surface area assessments of corals for various applications, including assessments of biotic surface area, tissue biomass, calcification rates, coral demographic rates, and reef restoration monitoring. [ABSTRACT FROM AUTHOR]

Compact bushy and expansive branching Acropora survival rates were compared in an experimental restoration setting. Coral fragments were sourced as corals of opportunity (CoPs) or refragmented from CoPs reared on a floating mid‐water rope nursery. Fragments were attached in single‐species and mixed‐species aggregations to modular substrate stabilization structures (reef stars) on degraded, unconsolidated dead coral rubble slopes in Wakatobi Marine National Park, central Indonesia. In total, 1440 Acropora fragments were outplanted to 96 reef stars across five experimental restoration blocks at 14 m depth. Fragment survival was recorded 40–44 months post‐attachment. Survival had a significant relationship with fragment morphology (p < 0.001) and aggregation type (p < 0.01). Sourcing fragments as CoPs or from the nursery did not have a significant relationship with survival. No significant relationships were found with fragment survival for any interactions between morphology, outplanted aggregation, and source. Survival rates for bushy Acropora were 3.44 times and 5.25 times higher than for expansive species for direct CoP outplants and nursery‐reared corals, respectively. The results demonstrate the potential efficacy of returning complex bushy branching Acropora morphologies to mid‐depth reef slopes previously dominated by the genus, using single‐species aggregations interspersed with mixed‐species aggregations. The study also supports using mid‐water nurseries to create a closed or semi‐closed nursery cycle to scale up restoration, and proposes introducing the term "biomass production system" to distinguish this as a process distinct from other coral nursery approaches. [ABSTRACT FROM AUTHOR]

Mass culturing coral larvae collected from spawn slicks during spawning events and rearing them directly on reefs is an important method for coral reef restoration as it utilizes high genetic diversity and is readily upscaled. Understanding optimal initial stocking densities in mass cultures is, therefore, central to optimizing larval production efficiency. Yet, no studies have focused on optimizing initial stocking densities while coral embryos are still floating, despite the influence of density‐dependent effects during larval culturing. This study aimed to (1) explore initial stocking densities based on slick coverage and (2) determine the effects of initial densities on embryo development to coral settlement and early post‐settlement survival. Wild coral spawn slicks were collected at Lizard Island and reared at different combinations of slick coverage and density based on tank volume. Immediate density‐dependent effects were observed in treatments with 45% slick coverage, which had lower abundances of embryos 12 hours post‐spawning. The 12‐hour embryo densities ranged from 1.7 to 10.7 mL−1 and continued to display a negative relationship between density and survival of developing larvae. Overall, a density of approximately 5.1 embryos mL‐1 was the optimal stocking density for larval survival to competency (16.5%). The proportion of settlement and early post‐settlement survival was negatively correlated with higher initial densities, while a positive relationship was observed between the abundance of competent larvae and those settled, including initial settlers and 2‐month‐old recruits. These results highlight the importance of both larval quality and supply, and opportunities for site and system‐specific optimization of larval production in future work. [ABSTRACT FROM AUTHOR]

Reef restoration has gained attention as it has strategic actions and powerful means in sustaining and maintaining coastal ecosystem services. This scientometric study systematically analyzes the current trends and research hotspot in coral restoration across the last five decades (1971–2022). The metadata (12,667 articles with 652,860 cited references) were obtained from the Clarivate Web of Science platform through the Core Collection database, associated with the CiteSpace and R‐software for further analysis. The results indicated that the trend of coral restoration is increasing in paper/year, with the United States, Australia, and China as major contributors to the related research. Furthermore, James Cook University, Australia had the largest number of articles, and the Consortium of Research Libraries of the United Kingdom was the most influential institution on coral restoration. The highly cited keywords are "Great Barrier Reef," "climate change," and "coral reef," while the most influential keywords are "coral," "model," and "Atlantic." A total of 23 clusters in the field with "coral reef," "phase shift," "bacterial communities," "coral restoration," "symbiotic dinoflagellate," "stony coral tissue loss disease," "bleaching event," "ocean acidification," "oyster reef," and "quantitative reconstruction" are among the top cluster size labeled. Early‐stage researcher may use both keywords and cluster analysis to find topics attractive to their future research projects. In addition, this study contributes toward evaluating recent scientific productivity about coral restoration as well as informing researchers and policymakers regarding funding, future strategic planning, and potential collaboration opportunities. [ABSTRACT FROM AUTHOR]

Understanding the mineralization of coral is significant for the formation of coral reefs and paleoclimatic reconstructions. However, the fundamental mechanisms involved in biomineralization are poorly understood. A combination of Raman spectral and cross-polarized reflected light microscopy imaging was used to examine the three-dimensional spatial distribution of the skeletal ultrastructures and their associated mineral, organic, and water chemistry in coral, which enable insight into the spatial growth features of the ultrastructures and possible formation processes. A possible mechanism is proposed that controls the formation of skeletal ultrastructures, which likely involves compartmentalized calcifying cells and their related cellular activities. This could clarify the association between coral skeletal mineralization and biology, and it may be beneficial to better protection and application of coral reefs. [ABSTRACT FROM AUTHOR]

Five new species of antipatharian corals are described from the New Zealand region. Differential diagnoses are given and comparisons are made to related nominal species. Described as new are: Anozopathes psednocrada, Aphanipathes rosemariae, and Acanthopathes candelabra in the family Aphanipathidae; Triadopathes trilix in the family Stylopathidae; and Lillipathes ventalina in the family Schizopathidae. [ABSTRACT FROM AUTHOR]

Demographic processes that ensure the recovery and resilience of marine populations are critical as climate change sends an increasing proportion on a trajectory of decline. Yet for some populations, recovery potential remains high. We conducted annual monitoring over 9 years (2012–2020) to assess the recovery of coral populations belonging to the genus Pocillopora. These populations experienced a catastrophic collapse following a severe typhoon in 2009. From the start of the monitoring period, high initial recruitment led to the establishment of a juvenile population that rapidly transitioned to sexually mature adults, which dominated the population within 6 years after the disturbance. As a result, coral cover increased from 1.1% to 20.2% during this time. To identify key demographic drivers of recovery and population growth rates (λ), we applied kernel‐resampled integral projection models (IPMs), constructing eight successive models to examine annual change. IPMs were able to capture reproductive traits as key demographic drivers over the initial 3 years, while individual growth was a continuous key demographic driver throughout the entire monitoring period. IPMs further detected a pulse of reproductive output subsequent to two further Category 5 typhoon events during the monitoring period, exemplifying key mechanisms of resilience for coral populations impacted by disturbance. Despite rapid recovery, (i.e., increased coral cover, individual colony growth, low mortality), IPMs estimated predominantly negative values of λ, indicating a declining population. Indeed, while λ translates to a change in the number of individuals, the recovery of coral populations can also be driven by an increase in the size of surviving colonies. Our results illustrate that accumulating long‐term data on historical dynamics and applying IPMs to extract demographic drivers are crucial for future predictions that are based on comprehensive and robust understandings of ecological change. [ABSTRACT FROM AUTHOR]

Bio‐logging has revealed much about high‐latitude seabird migratory strategies, but migratory behaviour in tropical species may differ, with implications for understanding nutrient deposition. Here we use combined light‐level and saltwater immersion loggers to study the year‐round movement behaviour of adult red‐footed boobies Sula sula rubripes from the Chagos Archipelago, tropical Indian Ocean, to assess migratory movements and estimate nutrient deposition rates based on the number of days they spent ashore. Light levels suggest that red‐footed boobies are resident in the Chagos Archipelago year‐round, although there are large latitudinal errors this close to the equator. Immersion data also indicate residency with tracked birds returning to land every one or two days. Spending an average of 79.86 ± 2.80 days and 280.84 ± 2.64 nights per year on land allows us to estimate that the 21 670 pairs of red‐footed boobies deposit 37.34 ± 0.56 tonnes year−1 of guano‐derived nitrogen throughout the archipelago. Our findings have implications for tropical seabird conservation and phylogenetics, as well as for assessing the impact of seabird nutrients on coral reef ecosystems. [ABSTRACT FROM AUTHOR]

Wedgefishes have recently been recognised as one of the most imperilled marine fish families worldwide. However, many knowledge gaps about their biology and ecology hinder conservation efforts. Here we used a combination of acoustic telemetry and acceleration datalogger technology to gain fundamental insights into the fine-scale behaviour, habitat use, size of activity spaces, and residency of adult female bottlenose wedgefish (Rhynchobatus australiae) in the Ningaloo region of northwestern Australia. Acoustic tracking data over one year demonstrated that female bottlenose wedgefish continuously resided in a relatively small area of a productive coral reef lagoon. Acceleration data revealed that bottlenose wedgefish were nocturnal, with time of day having a greater influence on activity than tidal patterns. Bottlenose wedgefish also increased activity with seasonally increasing temperatures. We identified several discrete behavioural signatures in the acceleration data, inferred to correspond to chafing, settling/burying behaviour, foraging behaviour, and escape behaviour, based on their kinematics. Further observations are required to confirm these behaviours with certainty. Additionally, according to datalogger and acoustic data, tagged bottlenose wedgefish rarely inhabited areas greater than 2 m deep. Together, these first insights into behaviour and habitat use of adult female bottlenose wedgefish highlight the importance of nearshore habitats for this species and indicate that they may be highly resident to specific areas. Our findings provide important insight into the conservation of bottlenose wedgefish in northwestern Australia, including potential effectiveness of protected areas and interactions with specific anthropogenic threats such as shoreline development and recreational beach fishing. [ABSTRACT FROM AUTHOR]

Sea hares are cryptic, herbivorous sea slugs present on many coral reefs worldwide. Although they are known to consume high quantities of macroalgae, they are rarely considered or quantified in assessing algal suppression. Their role as algal suppressors is not well understood, therefore this study sought to quantify sea hare herbivory on the abundant red algal genus Laurencia. The sea hares Aplysia dactylomela, Dolabella auricularia and Dolabella sp. were collected and used in herbivory trials in aquaria at Heron Island on the Southern Great Barrier Reef to quantify their rate of consumption. A. dactylomela consumed 76.9 g partially dried weight of Laurencia per 24-h, which was significantly more than the other species, with D. auricularia consuming an average of 22.5 g and Dolabella sp. consuming 37.4 g partially dried weight. Consumption of Laurencia by A. dactylomela increased with body size, with the exception of the smallest animals, which ate up to 12.5 times their body weight. D. auricularia consumed significantly more algae than was lost in control tanks. Although we observed Dolabella sp. feeding on Laurencia, the amount consumed was not significantly different to loss of algae in control tanks. The rate of herbivory on Laurencia by A. dactylomela is comparable or greater than that of more commonly studied reef herbivores such as fishes and urchins, which suggests that they may contribute to algal suppression on coral reefs and further studies are warranted to evaluate their possible role in coral-algal phase shift dynamics. [ABSTRACT FROM AUTHOR]

Due to the wide particle size distribution of coral sand, There are significant differences in mechanical behaviour of coral sand with different particle size distribution. It is of great significance to propose a quantitative analysis method for mechanical properties considering the effect of gradation. In this study, 27 groups of coral sand specimens with particle size ranging from 5 mm to 0.125 mm were prepared. The consolidated undrained (CU) triaxial shear tests were carried out and the influence of gradation and relative density on the shear characteristic were discussed. The grading and relative density of coral sand are controlled by the median particle size (d50) and relative density (Dr), The results show that the peak deviator stress decreased, and the effective internal friction angle first increased and then decreased with the increase of d50. Both the peak deviator stress and effective internal friction angle of coral sand increase with the relative density. A parabolic relationship was founded between the effect internal friction and d50 as Dr was constant. The effective friction angle peaked when d50 was 2 mm. Finally, a calculation method of shear strength parameter considering the gradation and relative density of coral sand was proposed. [ABSTRACT FROM AUTHOR]

Coral sand is known to have stress path dependence and fragility. In this research, a series of drained triaxial tests were conducted to explore stress path effects on the mechanical and particle breakage characteristics of coral sands. Several mechanical characteristics, such as critical state, strength, and dilatancy characteristics were studied. The results revealed that the dilatancy behaviors, stress-strain responses, and crushing of coral sands were strongly affected by consolidation stress and stress path. The critical state lines of coral sands were straight in p'-q space and e-(p'/Pa)0.44 plane regardless of stress path. Based on these characteristics, a dilatancy equation was derived and validated through test results. The developed dilatancy equation could predict the dilatancy relationships of coral sands under various stress paths. [ABSTRACT FROM AUTHOR]

SCoralNet (based on Faster R-CNN) is a new underwater coral detection framework that has been proposed to automatically localize and identify distinct coral species in images, allowing for fast and detailed annotation. Monitoring the coverage and abundance of underwater corals typically involves the annotation and processing of large amounts of underwater coral images. However, manually annotating a large number of images is time-consuming and labor-intensive, and CNN classifiers only provide simple classification annotations without capturing the images' finer details. SCoralNet's detection performance is improved by incorporating dilated convolutions into the backbone network. To successfully capture multi-scale and multi-level information from coral targets, a neck network called NASFPN is placed between the backbone and the detecting head. Seesaw Loss is used to reduce the impact of the dataset's long-tailed distribution on SCoralNet's classifier accuracy. CIoU loss is used to optimize the bounding box regression method. During inference, Soft-NMS is applied to suppress redundant coral detection boxes. To assess SCoralNet's effectiveness, a dataset called Coral-soft was developed using real-world photos of common soft coral species from the Sanya region of China. SCoralNet outperformed the original Faster R-CNN model on the Coral-soft dataset, with a 45.68% gain in mean average precision (mAP) and a 59.2% increase in mAP75. Furthermore, SCoralNet outperformed some advanced models in terms of overall performance. [ABSTRACT FROM AUTHOR]

While a record-high in situ water temperature of 38.4 °C on July 24, 2023, has been measured from a local site in Florida's Manatee Bay, satellite images revealed more extensive record-high water temperature in South Florida estuaries and the Florida Keys Reef Tract in July 2023 as a response to the 2023 heatwave, with an average sea surface temperature (SST) anomaly of 1.59 °C above the 2003–2022 mean. Long-term annual SST anomalies and long-term SST trend components of the time series both show significant warming trends in these regions between 2003 and 2023 (0.70 °C/decade), which is 67% higher than in the Gulf of Mexico (0.42 °C/decade). Furthermore, the warming trend appears to have accelerated over the past decade. In the context of global warming in the twenty-first century, such a warming trend and response to heatwaves may lead to more heat stress on the precious coral reefs and seagrasses both in and downstream from these already fragile estuaries. [ABSTRACT FROM AUTHOR]

The purpose of this paper is devoted to investigating a fractional egg-sperm chemotaxis model of coral in the whole space $ \mathbb{R}^{n}(n\geqslant3) $. In [4], the authors obtained the global well-posedness of solutions to the classical chemotaxis-Stokes system modeling coral fertilization in $ \mathbb{R}^{3} $. As a new exploration, we prove the global existence and obtain the optimal convergence rates of mild solution of the fractional chemotaxis-Navier-Stokes system modeling coral fertilization. [ABSTRACT FROM AUTHOR]

Coral mucus, teeming with organic matter, releases nutrients and microorganisms, affecting element cycling and microbial communities in coral reefs. While terrestrial ecosystems exhibit well‐studied priming effects from root exudates, the influence of mucus in marine environments, particularly in coral reefs, remains underexplored. We hypothesize that coral mucus, through its nutrients and microbes, stimulates the surrounding microorganisms, regulating carbon metabolism and thus contributing to high coral reef productivity. Initially, natural samples (Acropora pruinosa mucus, seawater, and sediment) were collected for metagenomic assessment of microbial communities and functions. Results showed significant differences in microbial diversity, community structures, co‐occurrence modes, and unique functions among mucus, seawater, and sediment. Subsequent laboratory experiments demonstrated mucus's substantial influence on surrounding microorganisms. Analyses, including 16S rRNA sequencing and Eco‐plate results, revealed that mucus regulates microbial composition and activities. Quantitative gene‐chip analysis showed significant increase in the functional genes related to carbon fixation (e.g., the 3‐hydroxypropionate cycle) and degradation (e.g., pectin and hemicellulose hydrolysis) by 55.81% and 65.48%, respectively. Partial least squares path modeling identified mucus nutrients and microbial community composition as key contributors to carbon metabolic potential. This research confirms that mucus acts as a trigger, reshaping microbial profiles around corals and enhancing carbon utilization efficiency, highlighting its essential role in carbon metabolism and the maintenance of high productivity in coral reef ecosystems. [ABSTRACT FROM AUTHOR]

One of the most significant features of the Northwest Atlantic, the Gulf Stream influences high magnitude environmental fluctuations in deep habitats across the South Atlantic Bight. Amid this variability, the Blake Plateau harbors extensive reefs formed by cold‐water corals that were previously assumed to rely on narrow ranges of temperature, currents, and particulate supply. A benthic lander collected near‐bed conditions at the Richardson Reef Complex, a cold‐water reef dominated by the scleractinian Desmophyllum pertusum at 830 m within the path of the Gulf Stream. Specific behavior of the Gulf Stream resulted in recurring environmental patterns at depth. During offshore meanders, deep stream components intruded onto the reef and caused rapid (3.74°C per hour) temperature increases up to 10.8°C (> 5°C above the site mean) and increased chlorophyll. Within 2 d of peak temperatures, intrusions were replaced by strong, turbid upwelling currents that rapidly cooled the site to temperature minima (4.13°C). While considerable environmental variability from the Gulf Stream may otherwise implicate a thermally stressful setting for corals, high‐temperature events were likely mitigated by their short duration (< 37.4 h) and physical coupling with enhanced organic material. This hypothesis was supported by high‐density clustering of D. pertusum occurrences within 50 km around the Gulf Stream's position along the South Atlantic Bight. This suggests that cold‐water corals experiencing environmental variability can be sustained by relationships between food supply, temperature, and currents that vary in strength along stochastic time scales, shedding further light on the niche of cold‐water corals. [ABSTRACT FROM AUTHOR]

The timing of larval production and release of organisms is important in understanding their presence and prevalence in the environment. On the subtropical coral reefs around Okinawa Island, Japan, the reproductive timing of many soft coral species is still largely unknown. In this study, we report the first documentation of in situ external brooding and planulae release of a stoloniferan octocoral observed on the coral reefs of Okinawa Island. We observe external brooding of embryos and developing larvae on the colony surface and the subsequent planulation of some azooxanthellate larvae of Clavularia cf. inflata from two coral reef sites in the northwestern region of Okinawa Island. These observations indicate that this species reproduces concurrently with other zooxanthellate coral reef anthozoans in the summer season. [ABSTRACT FROM AUTHOR]

Introduction: Cold-water coral reefs form complex benthic habitats, supporting thousands of species. The broadscale environmental tolerances of reef-forming species such as Lophelia pertusa are well studied, but small-scale differences between different reef settings have received little attention so far. The controlling factors of thriving cold-water coral reefs and how these habitats differ in terms of framework extent, coral colony morphology, and associated fauna could reveal how these benthic ecosystems formand expand. Information on the natural range of environmental fluctuations could provide a better understanding of the resilience of such ecosystems towards environmental changes. Our study aimed to elaborate small-scale forces on local hydrodynamics and oceanographic parameters at two geographically close but contrasting reef sites in mid-Norway. Methods: We investigated natural fluctuations and the seasonal variability of environmental conditions of an inshore and an offshore Lophelia-dominated reef over an annual cycle by time series monitoring of physical properties by benthic landers and water sampling for biogeochemical variables using CTD casts. Results and discussion: The flow fields at the extensive reef on the offshore Sula Ridge and a bank reef at Nord-Leksa in a fjord-system differed regarding both short-term and seasonal levels. The inshore flow field was strong and tidally driven, whereas the offshore flow field was slower with large seasonal variability. The local flow regimes and the seasonal atmospheric forcing could explain the observed seasonality of the hydrographic variables and the observed inter-annual variability in biogeochemical variables. Comparison with a flow model showed that the natural short-term and seasonal variability are driven by small-scale forcing that is not represented in model analyses. These results suggest that local hydrodynamics together with sea-floor topography control the reef extent and the morphology of cold-water coral colonies. [ABSTRACT FROM AUTHOR]

Coral reefs are biodiverse marine ecosystems that are undergoing rapid changes, making monitoring vital as we seek to manage and mitigate stressors. Healthy reef soundscapes are rich with sounds, enabling passive acoustic recording and soundscape analyses to emerge as cost-effective, long-term methods for monitoring reef communities. Yet most biological reef sounds have not been identified or described, limiting the effectiveness of acoustic monitoring for diversity assessments. Machine learning offers a solution to scale such analyses but has yet to be successfully applied to characterize the diversity of reef fish sounds. Here we sought to characterize and categorize coral reef fish sounds using unsupervised machine learning methods. Pulsed fish and invertebrate sounds from 480 min of data sampled across 10 days over a 2-month period on a US Virgin Islands reef were manually identified and extracted, then grouped into acoustically similar clusters using unsupervised clustering based on acoustic features. The defining characteristics of these clusters were described and compared to determine the extent of acoustic diversity detected on these reefs. Approximately 55 distinct calls were identified, ranging in centroid frequency from 50 Hz to 1,300 Hz. Within this range, two main sub-bands containing multiple signal types were identified from 100 Hz to 400 Hz and 300 Hz-700 Hz, with a variety of signals outside these two main bands. These methods may be used to seek out acoustic diversity across additional marine habitats. The signals described here, though taken from a limited dataset, speak to the diversity of sounds produced on coral reefs and suggest that there might be more acoustic niche differentiation within soniferous fish communities than has been previously recognized. [ABSTRACT FROM AUTHOR]

Stony Coral Tissue Loss Disease (SCTLD) has caused widespread coral mortality in the Caribbean Region. However, how the disease presence alters the microbiome community, their structure, composition, and metabolic functionality is still poorly understood. In this study, we characterized the microbial communities of the tissues of apparently healthy and diseased SCTLD colonies of the species Siderastrea siderea, Orbicella faveolata, and Montastraea cavernosa to explore putative changes related to the presence of SCTLD. Gammaproteobacteria, Alphaproteobacteria, and Bacteroidia were the best represented classes in the healthy tissues of all coral species, and alpha diversity did not show significant differences among the species. The microbial community structure between coral species was significantly different (PERMANOVA: F = 3.46, p = 0.001), and enriched genera were detected for each species: Vibrio and Photobacterium in S. siderea, Spirochaeta2 and Marivivens in O. faveolata and SAR202_clade and Nitrospira in M. cavernosa. Evidence of SCTLD in the microbial communities was more substantial in S. siderea, where differences in alpha diversity, beta diversity, and functional profiles were observed. In O. faveolata, differences were detected only in the community structure, while M. cavernosa samples showed no significant difference. Several microbial groups were found to have enriched abundances in tissue from SCTLD lesions from S. siderea and O. faveolata, but no dominant bacterial group was detected. Our results contribute to understanding microbial diversity associated with three scleractinian coral species and the shifts in their microbiomes associated with SCTLD in the Mexican Caribbean. [ABSTRACT FROM AUTHOR]

In this paper, we construct a family of self-similar networks, named Coral networks, whose Iterated Function System (IFS) contains a rotation transformation. Using self-similarity, we obtain the weighted average geodesic distance of Coral fractal and networks. [ABSTRACT FROM AUTHOR]

ABSTRACT The warm Miocene (23.0–5.3 Ma) is considered a model case for the global climate of the near future. In view of the current coral reef crisis, studies on Miocene reefs can contribute to predictions regarding the stress resilience of today's reefs against global warming. A Late Miocene (6.2–5.5 Ma) reef coral fauna from Hispaniola Island (Caribbean) characterised by ecologically tolerant taxa was originally interpreted to reflect cool‐eutrophic waters. However, the associated planktonic foraminifer assemblage and new TEX86H–based temperature reconstructions document an oligotrophic shallow‐water environment harbouring 30–31°C. Thus, in conjunction with unusually low vertical growth rates and erratic trace element signatures of massive reef corals, the coral fauna documents critically high temperatures and a response to heat stress rather than cool upwelling. The findings demonstrate the relevance of understanding shallow‐water ecosystems from past warm periods for developing scenarios of a future, warmer world. [ABSTRACT FROM AUTHOR]

In the Caribbean, reef-building scleractinian corals have declined precipitously and octocorals have emerged as one of their main successors. The success of octocorals and the formation of octocoral forests has been attributed to their continuing recruitment to reef habitats, as well as tolerance to pollution, reduced direct competition with scleractinians, and resistance and resilience to climatic events. Benthic grazers on coral reefs can facilitate the growth and recruitment of corals by reducing the abundance of competitive algal turfs and macroalgae. However, grazing can also hinder corals through sublethal damage to coral tissue and predation of recruits. We assessed the effects of grazing by fishes and the sea urchin Diadema antillarum as well as predation by mesofauna on octocoral recruitment through a series of manipulative in situ and ex situ experiments. Exposure to fish and urchin grazing significantly reduced the post-settlement survival of octocoral recruits, while turf-associated mesofauna did not significantly affect recruitment. We also found a positive relationship between octocoral recruitment and the abundance of turf algae, which may reflect the deleterious effect of grazing on both turf algae and octocoral recruits. These data suggest that grazers and predators mediate the bottleneck characteristic of recruitment, primarily through their effect on post-settlement survival. Thus, the declines in the abundance of grazing fishes and urchins throughout the Caribbean may have contributed to the increase in Caribbean octocoral abundance, concurrent with the loss of scleractinians. [ABSTRACT FROM AUTHOR]

Understanding settling motion of coral grains is important in terms of protection of coral reef systems and resotoration of the associated ecosystems. In this paper, a series of laboratory experiments was conducted to investigate the settling motion, using optical microscopy to measure shape parameters of coral grains and the particle-filtering-based object tracking to reconstruct the three-dimensional trajectory. Three characteristic descent regimes, namely, tumbling, chaotic and fluttering, are classified based on the three-dimensional trajectory, the spiral radius variation and the velocity spectrum. It is demonstrated that if one randomly picks up one coral grain, then the probabilities of occurrence of the three regimes are approximately $26\,\%$ , $42\,\%$ and $32\,\%$ , respectively. We have shown that first, the dimensionless settling velocity generally increases with the non-dimensional diameter and Corey shape factor and second, the drag coefficient generally decreases with the Reynolds number and Corey shape factor. Based on this, the applicability of existing models on predicting settling velocity and drag coefficient for coral grains is demonstrated further. Finally, we have proposed extended models for predicting the settling velocity. This study contributes to better understanding of settling motion and improves our predictive capacity of settling velocity for coral grains with complex geometry. [ABSTRACT FROM AUTHOR]

Scientific advances in environmental data coverage and machine learning algorithms have improved the ability to make large‐scale predictions where data are missing. These advances allowed us to develop a spatially resolved proxy for predicting numbers of tropical nearshore marine taxa. A diverse marine environmental spatial database was used to model numbers of taxa from ∼1000 field sites, and the predictions were applied to all 7039 6.25‐km2 reef cells in 9 ecoregions and 11 nations of the western Indian Ocean. Our proxy for total numbers of taxa was based on the positive correlation (r2 = 0.24) of numbers of taxa of hard corals and 5 highly diverse reef fish families. Environmental relationships indicated that the number of fish species was largely influenced by biomass, nearness to people, governance, connectivity, and productivity and that coral taxa were influenced mostly by physicochemical environmental variability. At spatial delineations of province, ecoregion, nation, and strength of spatial clustering, we compared areas of conservation priority based on our total species proxy with those identified in 3 previous priority‐setting reports and with the protected area database. Our method identified 119 locations that fit 3 numbers of taxa (hard coral, fish, and their combination) and 4 spatial delineations (nation, ecoregion, province, and reef clustering) criteria. Previous publications on priority setting identified 91 priority locations of which 6 were identified by all reports. We identified 12 locations that fit our 12 criteria and corresponded with 3 previously identified locations, 65 that aligned with at least 1 past report, and 28 that were new locations. Only 34% of the 208 marine protected areas in this province overlapped with identified locations with high numbers of predicted taxa. Differences occurred because past priorities were frequently based on unquantified perceptions of remoteness and preselected priority taxa. Our environment–species proxy and modeling approach can be considered among other important criteria for making conservation decisions. [ABSTRACT FROM AUTHOR]

Coral reef degradation is a worldwide and growing phenomenon triggering habitat transformation from live to dead coral fragments. Macroinvertebrates play key functions in coral reefs, yet research on the size distribution of their community attributes is limited, particularly in the Eastern Tropical Pacific (ETP). We assessed the size distribution of the macroinvertebrate communities in live and dead corals in an ETP coral reef off Colombia. Live coral supported greater macroinvertebrate biomass than dead corals. In live coral, > 90% of total biomass was allocated in the > 8 mm class, which was mostly represented by trapeziid crabs and alpheid shrimps, both obligate symbionts of Pocillopora colonies. No differences were found in macroinvertebrate densities between substrates. Macroinvertebrate communities were dominated by crustaceans, though not in every size class. In live coral, Decapoda dominated in all size classes except 0.5–1 mm, which was the only class where dominance of a single taxon was not observed. In dead corals, the dominance of crustaceans was only observed in the 0.5–1 mm class due to high abundances of tanaidaceans. The remaining size classes were dominated by Polychaeta (1–2 mm, 2–4 mm) and Ophiuroidea (4–8 mm, > 8 mm). Our findings highlight that coral degradation events could lead to macroinvertebrate assemblages with lower biomass contributions, higher proportions of small crustaceans (< 1 mm), and taxonomic shifts. Such transitions from live to dead corals could likely impact food-web interactions between macroinvertebrates and higher trophic levels, potentially altering the ecosystem services offered by coral reefs. [ABSTRACT FROM AUTHOR]

The growth properties and environmental adaptability of different corals and symbionts vary. Therefore, insights from the adaptive mechanisms of Symbiodiniaceae in corals are very meaningful. In this study, we surveyed the seawater characteristics at three sites on Luhuitou fringing reef, Hainan Island (China), sampling three native corals Pocillopora damicornis, Acropora hyacinthus, and Galaxea fascicularis on 27 September 2021. The photo-physiological (Fv/Fm, Y(II), α, and rETR) were measured, and high-throughput sequencing of Symbiodiniaceae ITS was performed. The Luhuitou site had the lowest temperature (28.845 °C ± 0.01), salinity (33.967 ± 0.03), and pH (8.468 ± 0.05) among the three sites. The Sanya site contained significantly the highest ammonium (7.406 μmol/L ± 1, P < 0.05). The nitrate of the Xiaozhou site was 1.5 times significantly higher than the other two sites. Three corals and their Symbiodiniaceae were adapted differently. P. damicornis showed more plasticity and was dominant by Cladocopium sp. C1d at high-ammonium habitat. A. hyacinthus was dominated by Cladocopium (C3 and C1232) and they had the lowest Fv/Fm (0.595 ± 0.02) in poor integrated water quality environments (the Xiaozhou site) among three corals, suggesting that the less adaptation. G. fascicularis established a stable symbiotic relationship with Durusidinium sp. D1, and they had a more stable symbiotic system and were better suited for long-term reef restoration. Our results provide a deeper understanding of the environmental adaptations of three corals at the Luhuitou fringing reef. Meanwhile, it provides a perspective application for coral transplantation species selection in restoring local reef ecology in the future. [ABSTRACT FROM AUTHOR]

Coral reef fishes are usually assumed to be most strongly associated with reef-building corals. However, sponges can be a significant structural component of coral reef ecosystems and their framework can enhance the local abundance and biodiversity of fish assemblages. Little is known regarding the range of fish species using complex sponges as either shelter or feeding substrata. Here we use a combination of stationary video cameras and focal animal sampling to document fish species positively associated with complex sponges in Kimbe Bay, Papua New Guinea. Stationary cameras identified 45 fish species using the sponges for either shelter, feeding substrata or as sites for ambush predation. A guild of 10 individual fish species from five families (Blenniidae, Chaetodontidae, Gobiidae, Labridae and Pomacentridae) were observed to quantify sponge and other habitat use and compared with habitat availability to determine the level of sponge selectivity. One species, Pleurosicya elongata (the Slender Spongegoby), lived in obligate association with Ianthella basta (Elephant Ear sponge), and there was a positive relationship between sponge size and number of resident fish, however this was not significant for all life stages. Five other fish species appeared to preferentially select sponges as habitat (Amblyglyphidodon aureus, Chaetodon kleinii, Coradion chrysozonus, Escenius prooculis and Pomacentrus nigromanus), while for others, sponge use appeared incidental. When selectivity indices were calculated for specific sponge species it was apparent that some fishes exhibited preferences for particular sponge species or growth forms. These results suggest more fish species may be reliant on sponges than is widely appreciated. [ABSTRACT FROM AUTHOR]

How can phenotypic plasticity promote or impede adaptive change and diversification? Answering this key question can be experimentally intractable, but closely related clonal species allow a direct approach: experimentally provoking phenotypic plasticity to assess the adaptive significance of both plastic traits and species differences. Two common Caribbean sponge species, Aplysina fulva and A. cauliformis , are nearly indistinguishable molecularly, and share growth form, habitat, and geographical range. This raises questions about species boundaries, within-species variability, and mechanisms of speciation. To distinguish phenotypic plasticity from genetic variation, and learn how plasticity might influence adaptive—and divergent—evolution, I: (i) quantified morphological and ecological characters, (ii) revealed phenotypic plasticity by growing clonemates in different environments, and (iii) related plastic morphological features to ecological function. Characters included skeletal fibre density, biomechanical properties, vulnerability to parasites and predators, wound healing, transport pathways, propagation by fragments, population dynamics, and growth and survival in settings differing in food, sunlight, predators, and water motion. Transplanting both species to a different environment elicited parallel plasticity in the same traits. Combined comparative and experimental data reveal integrated suites of ecologically relevant characters that clearly distinguish these species and allow interpretation of adaptive significance of plastic characters that may underlie divergence. [ABSTRACT FROM AUTHOR]

Monitoring changes in coral reef ecosystems for their conservation and management is important as they are frequently subject to various natural and anthropogenic threats. However, in Sri Lanka, the attention in this regard is to be further concerned for their well‐being. Therefore, this study focused on the selected shallow water (<5 m) coral reefs as Pigeon Island (PIR), Adukkuparu (AR), Salli Beach (SBR), Kayankerni (KR), and Passikuda (PR) on the Eastern coast of Sri Lanka to estimate their changes over 2020, 2021, and 2022. The remote sensing demarcations with the composition of reef ecosystems were done through the analysis of the Allen Coral Atlas data followed by field surveys. Higher accuracy levels for corals were obtained for each site due to field verifying all individual polygons and omitting unmatched polygons of the initial maps from the Allen Coral Atlas. Then, the in‐situ reef surveys were conducted over randomly selected permanent transects at each site. From 2020 to 2022, the live coral percentages have increased in PIR, AR, and SBR while reduced in KR and PR. Dead corals have facilitated the overgrowth of macroalgae. The combined area of live coral on all five reefs has slightly gone up. This increase is primarily due to the rise in live coral cover in AR and SBR. Also, prominent increments of coral diversity have resulted from those sites. Therefore, it is suggested that AR and SBR be designated as Marine Protected Areas to safeguard the newly emerging live corals. [ABSTRACT FROM AUTHOR]

There are unique reef patches in the Biosphere Reserve Banco Chinchorro reef lagoon that have an unusual formation. They appear to be miniature atolls. These formations are at a depth of 2–6 m, and present flourishing coral growth, whereas a few meters away others are strongly decayed. To define the cause of this phenomenon, an analysis of three of these formations was carried out to try to relate the structure of the corals that make up these formations to environmental factors. We recorded in tidal cycles, 12 environmental parameters, and micronutrients. Despite their closeness, two patches show high biodiversity, whereas the third shows low diversity. These results show notable differences between the three patches resulting from position on the reef (leeward and windward), in addition, these patterns relate to the undercurrent of possible relict water that drains from the lagoon microsystem of the main island of the reef, Cayo Centro, toward the miniature atolls. [ABSTRACT FROM AUTHOR]

While the presence of morphologically cryptic species is increasingly recognized, we still lack a useful understanding of what causes and maintains co‐occurring cryptic species and its consequences for the ecology, evolution, and conservation of communities. We sampled 724 Pocillopora corals from five habitat zones (the fringing reef, back reef, and fore reef at 5, 10, and 20 m) at four sites around the island of Moorea, French Polynesia. Using validated genetic markers, we identified six sympatric species of Pocillopora, most of which cannot be reliably identified based on morphology: P. meandrina (42.9%), P. tuahiniensis (25.1%), P. verrucosa (12.2%), P. acuta (10.4%), P. grandis (7.73%), and P. cf. effusa (2.76%). For 423 colonies (58% of the genetically identified hosts), we also used psbAncr or ITS2 markers to identify symbiont species (Symbiodiniaceae). The relative abundance of Pocillopora species differed across habitats within the reef. Sister taxa P. verrucosa and P. tuahiniensis had similar niche breadths and hosted the same specialist symbiont species (mostly Cladocopium pacificum) but the former was more common in the back reef and the latter more common deeper on the fore reef. In contrast, sister taxa P. meandrina and P. grandis had the highest niche breadths and overlaps and tended to host the same specialist symbiont species (mostly C. latusorum). Pocillopora acuta had the narrowest niche breadth and hosted the generalist, and more thermally tolerant, Durusdinium gynnii. Overall, there was a positive correlation between reef habitat niche breadth and symbiont niche breadth—Pocillopora species with a broader habitat niche also had a broader symbiont niche. Our results show how fine‐scale variation within reefs plays an important role in the generation and coexistence of cryptic species. The results also have important implications for how niche differences affect community resilience, and for the success of coral restoration practices, in ways not previously appreciated. [ABSTRACT FROM AUTHOR]

Climate‐driven alterations to disturbance regimes are increasingly disrupting patterns of recovery in many biomes. Here, we examine the impact of disturbance and subsequent level of recovery in live hard coral cover on the Great Barrier Reef (GBR) across the last three decades. We demonstrate that a preexisting pattern of infrequent disturbances of limited spatial extent has changed to larger and more frequent disturbances, dominated by marine heatwaves and severe tropical cyclones. We detected an increase in the impact (measured as coral loss) across 265 individual disturbance impacts on 131 reefs in a 36‐year dataset (1985–2022). Additionally, the number of survey reefs impacted by disturbance has increased each decade from 6% in the 1980s to 44% in the 2010s, as has the frequency of mass coral bleaching across the GBR, which has increased between 19% and 28% per year, and cyclones (3%–5% per year), resulting in less time for recovery. Of the 265 disturbance impacts we recorded, complete recovery to the highest levels of coral cover recorded earlier in this study (the "historical benchmark") occurred only 62 (23%) times. Of the 23% of disturbance impacts that resulted in complete recovery to historical benchmarks, 34/62 recovered to their benchmark in 2021 or 2022. Complete recovery was more likely when the historical benchmark was <25% live hard coral cover. The lack of recovery was attributed to recovery time windows becoming shorter due to increases in the frequency of cyclones and of thermal stress events that result in mass coral bleaching episodes. These results confirm that climate change is contributing to ecosystem‐wide changes in the ability of coral reefs to recover. [ABSTRACT FROM AUTHOR]

Coral microbiomes differ in the mucus, soft tissue and skeleton of a coral colony, but whether variations exist in different tissues of a single polyp is unknown. In the stony coral, Fimbriaphyllia ancora, we identified 8,994 amplicon sequencing variants (ASVs) in functionally differentiated polyp tissues, i.e., tentacles, body wall, mouth and pharynx, mesenterial filaments, and gonads (testes and ovaries), with a large proportion of ASVs specific to individual tissues. However, shared ASVs comprised the majority of microbiomes from all tissues in terms of relative abundance. No tissue‐specific ASVs were found, except in testes, for which there were only two samples. At the generic level, Endozoicomonas was significantly less abundant in the body wall, where calicoblastic cells reside. On the other hand, several bacterial taxa presented significantly higher abundances in the mouth. Interestingly, although without statistical confirmation, gonadal tissues showed lower ASV richness and relatively high abundances of Endozoicomonas (in ovaries) and Pseudomonas (in testes). These findings provide evidence for microbiome heterogeneity between tissues within coral polyps, suggesting a promising field for future studies of functional interactions between corals and their bacterial symbionts. [ABSTRACT FROM AUTHOR]

Understanding accurately the influence of non-plastic fines on stress-dilatancy of coral sand mixture-packing is crucial for marine engineering in various geotechnical applications. This work experimentally examined the effects of non-plastic fines and initial test conditions on stress-dilatancy behavior of mixture. Based on test results, equivalent void ratio ( e ∗ ) was determined to quantify the global effect of fines on shear behavior across different shear stages. Test results show that e ∗ exhibits a reduction as the mean effective stress ( p ′ ) increases, following a power function relationship. Besides, e ∗ variation under phase transformation, peak state, and critical state can be described by a normalized curve. Reduced fines content and increased relative density can contribute to the enhancement of both peak strength and internal friction angle within the mixture. However, the smooth shape and lubrication function facilitated by fines actively contribute to initiation of shear contraction. Furthermore, the stress paths observed in the CD shear tests manifest as a sequence of parallel straight lines within the q - p ′ plane. The length of these lines progressively extends as the stress level escalates. Moreover, deviator stress in q - p ′ curves under character state presents lower and upper limits which are 0.334 and 0.639 corresponding to tested samples determined by fines content and relative density. Elevated fines content combined with reduced relative density can lead to a reduction in both peak-state friction angle and maximum angle of dilation. [ABSTRACT FROM AUTHOR]

This article discusses the interactions among three nonindigenous coral species in a tropical marine fouling community. The study focuses on the Tubastraea species, which are invasive corals originally from the tropical Indo-Pacific. The researchers found that these invasive corals can coexist and interact with each other without causing harm. They also observed fusion between colonies of different Tubastraea species, creating chimeric colonies. The study highlights the importance of understanding the interactions between invasive and native species in marine ecosystems. [Extracted from the article]

In the 20th century, Australia's Great Barrier Reef emerged as a political battleground when governing bodies planned to turn its coral territories into a vast mining zone. But in the 21st century, as the temporalisation of the Reef exerts increasing influence on the governance, securitisation and anticipation of planetary futures, coral time has emerged as a new site of political and imaginative conflict. Responding to this shift from territory to temporality, how can we pay closer attention to those skilfully making coral time? In this article, I introduce 'dimensional friction' as a tool for considering how the temporal structure of corals intersects with the temporal structure of global climate science in a coring laboratory. Based on my fieldwork at the Australian Institute of Marine Science, I analyse simultaneously discursive, technical, and imaginative problems that emerge when scientists transform the mineral skeletons of corals into time data. Dimensional friction appears whenever this skeletal matter is manipulated, surfacing the lab-based production of vertical time-depth but also suggesting other ways of temporalising (and corporally appropriating) coral time. Viewed in this way, coral cores might be better understood as 'temporal volumes' rather than chronostratigraphic records amenable to linear timelines and trajectories. [ABSTRACT FROM AUTHOR]

The utility of the mitochondrial genomes (mitogenomes) in analyzing the evolutionary history of animals has been proven. Five deep-sea corals (Bathypathes sp.1, Bathypathes sp.2, Schizopathidae 1, Trissopathes sp., and Leiopathes sp.) were collected in the South China Sea (SCS). Initially, the structures and collinearity of the five deep-sea coral mitogenomes were analyzed. The gene arrangements in the five deep-sea coral mitogenomes were similar to those in the order Antipatharia, which evidenced their conservation throughout evolutionary history. Additionally, to elucidate the slow evolutionary rates in Hexacorallia mitogenomes, we conducted comprehensive analyses, including examining phylogenetic relationships, performing average nucleotide identity (ANI) analysis, and assessing GC-skew dissimilarity combining five deep-sea coral mitogenomes and 522 reference Hexacorallia mitogenomes. Phylogenetic analysis using 13 conserved proteins revealed that species clustered together at the order level, and they exhibited interspersed distributions at the family level. The ANI results revealed that species had significant similarities (identity > 85%) within the same order, while species from different orders showed notable differences (identity < 80%). The investigation of the Hexacorallia mitogenomes also highlighted that the GC-skew dissimilarity was highly significant at the order level, but not as pronounced at the family level. These results might be attributed to the slow evolution rate of Hexacorallia mitogenomes and provide evidence of mitogenomic diversity. Furthermore, divergence time analysis revealed older divergence times assessed via mitogenomes compared with nuclear data, shedding light on significant evolutionary events shaping distinct orders within Hexacorallia corals. Those findings provide new insights into understanding the slow evolutionary rates of deep-sea corals in all lineages of Hexacorallia using their mitogenomes. [ABSTRACT FROM AUTHOR]

Aim: Predicting and acting on the future of ecosystems requires understanding species distribution shifts due to climate change. We investigated which corals are more likely to shift their distribution in the Southwestern Atlantic under a warming scenario. Location: Southwestern Atlantic (SWA; 1° N–28° S). Methods: We used spatial distribution models with a Bayesian approach to predict the current and future (2050 and 2100) coral occurrence probabilities of 12 zooxanthellate corals and hydrocorals under an intermediate scenario of increasing greenhouse gas emissions (RCP6.0) projected by the Intergovernmental Panel on Climate Change (IPCC). Results: We found a decline in the occurrence probabilities of all 12 taxa within the tropics (1° N–20° S) and an increase towards subtropical sites (20–28° S) as early as 2050. The most significant declines are projected to occur between 9° S and 20° S, a region that currently hosts the richest reef complex in the South Atlantic, the Abrolhos bank. The imminent loss of suitable habitat in the tropics mostly threatens the Brazilian endemics and range restricted corals Mussismilia braziliensis and Mussismilia harttii, while more widely distributed taxa such as Siderastrea spp., Millepora spp. and Porites spp. are expected to expand their ranges southwards. Main Conclusions: The projected declines in the tropical region are likely to reduce structural complexity causing biodiversity loss. The overall increase in occurrence probabilities in subtropical areas indicates tropicalisation of SWA reefs, which may benefit species already established in these areas and potentially enrich coral assemblages through the range expansion of taxa that currently do not occur in the region. These findings emphasise the need to support ecological corridors that could aid coral migration towards more suitable habitats under climate change. [ABSTRACT FROM AUTHOR]