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Nature Communications Jun 2024With increasingly intense marine heatwaves affecting nearshore regions, foundation species are coming under increasing stress. To better understand their impacts, we...
With increasingly intense marine heatwaves affecting nearshore regions, foundation species are coming under increasing stress. To better understand their impacts, we examine responses of critical, habitat-forming foundation species (macroalgae, seagrass, corals) to marine heatwaves in 1322 shallow coastal areas located across 85 marine ecoregions. We find compelling evidence that intense, summer marine heatwaves play a significant role in the decline of foundation species globally. Critically, detrimental effects increase towards species warm-range edges and over time. We also identify several ecoregions where foundation species don't respond to marine heatwaves, suggestive of some resilience to warming events. Cumulative marine heatwave intensity, absolute temperature, and location within a species' range are key factors mediating impacts. Our results suggest many coastal ecosystems are losing foundation species, potentially impacting associated biodiversity, ecological function, and ecosystem services provision. Understanding relationships between marine heatwaves and foundation species offers the potential to predict impacts that are critical for developing management and adaptation approaches.
Topics: Ecosystem; Animals; Biodiversity; Anthozoa; Seaweed; Aquatic Organisms; Hot Temperature; Global Warming; Seasons; Climate Change
PubMed: 38871692
DOI: 10.1038/s41467-024-49307-9 -
Scientific Reports Jun 2024Connectivity aids the recovery of populations following disturbances, such as coral bleaching and tropical cyclones. Coral larval connectivity is a function of physical...
Connectivity aids the recovery of populations following disturbances, such as coral bleaching and tropical cyclones. Coral larval connectivity is a function of physical connectivity and larval behaviour. In this study, we used OceanParcels, a particle tracking simulator, with 2D and 3D velocity outputs from a high resolution hydrodynamic-biogeochemical marine model (RECOM) to simulate the dispersal and settlement of larvae from broadcast spawning Acropora corals in the Moore Reef cluster, northern Great Barrier Reef, following the annual spawning events in 2015, 2016 and 2017. 3D velocity simulations showed 19.40-68.80% more links and sinks than those of 2D simulations. Although the patterns of connectivity among sites vary over days and years, coral larvae consistently dispersed from east to west in the cluster domain, with some sites consistently acting as sources or sinks for local larval recruitment. Results can inform coral reef intervention plans for climate change, such as the design of marine protected areas and the deployment of proposed interventions within reef clusters. For example, the wider benefits of interventions (e.g., deployment of heat adapted corals) may be optimised when deployed at locations that are a source of larvae to others within comparable habitats across the reef cluster.
Topics: Coral Reefs; Anthozoa; Animals; Larva; Climate Change; Ecosystem; Coral Bleaching
PubMed: 38866879
DOI: 10.1038/s41598-024-64388-8 -
Scientific Reports Jun 2024Restoration methods that seed juvenile corals show promise as scalable interventions to promote population persistence through anthropogenic warming. However, challenges...
Restoration methods that seed juvenile corals show promise as scalable interventions to promote population persistence through anthropogenic warming. However, challenges including predation by fishes can threaten coral survival. Coral-seeding devices with refugia from fishes offer potential solutions to limit predation-driven mortality. In an 8-month field study, we assessed the efficacy of such devices for increasing the survival of captive-reared Acropora digitifera (spat and microfragments) over control devices (featureless and caged). Devices with fish-exclusion features demonstrated a twofold increase in coral survival, while most corals seeded without protection suffered mortality within 48 h. Overall, spat faced more grazing and higher mortality compared to microfragments, and upward-facing corals were more vulnerable than side-facing corals. Grazing-induced mortality varied by site, with lower activity in locations abundant in mat-forming cyanobacteria or Scleractinian corals. Many scraping parrotfish were found feeding on or near the seeded corals; however, bites by Scarus globiceps explained the most site-related variation in grazing. Cyanobacteria may be preferred over corals as a nutritional resource for scraping parrotfish-advancing our understanding of their foraging ecology. Incorporating side-facing refugia in seeding devices and deploying to sites with nutrient-rich food sources for fish are potential strategies to enhance coral survival in restoration programs.
Topics: Animals; Coral Reefs; Anthozoa; Fishes; Predatory Behavior; Conservation of Natural Resources
PubMed: 38858572
DOI: 10.1038/s41598-024-64294-z -
ZooKeys 2024A new family of antipatharian corals, Ameripathidae (Cnidaria: Anthozoa: Antipatharia), is established for Opresko & Horowitz, The new family resembles Myriopathidae...
A new family of antipatharian corals, Ameripathidae (Cnidaria: Anthozoa: Antipatharia), is established for Opresko & Horowitz, The new family resembles Myriopathidae and Stylopathidae in terms of the morphology of the polyps and tentacles and the pinnulate branching of the corallum. Phylogenetic analysis using a genomic data set of 741 conserved element loci indicates that the new family is sister to a clade containing the Myriopathidae, Stylopathidae, Antipathidae, and Aphanipathidae.
PubMed: 38855792
DOI: 10.3897/zookeys.1203.121411 -
Scientific Data Jun 2024The skeletons of long-lived bamboo coral (Family Keratoisididae) are promising archives for deep-water palaeoceanographic reconstructions as they can record...
The skeletons of long-lived bamboo coral (Family Keratoisididae) are promising archives for deep-water palaeoceanographic reconstructions as they can record environmental variation at sub-decadal resolution in locations where in-situ measurements lack temporal coverage. Yet, detailed three dimensional (3D) characterisations of bamboo coral skeletal architecture are not routinely available and non-destructive investigations into microscale variations in calcification are rare. Here, we provide high-resolution micro-focus computed tomography (µCT) data of skeletal density for two species of bamboo coral (Acanella arbuscula: 5 specimens, voxel size, 15 µm (central branch scans) and 50 µm (complete structure scan); Keratoisis sp.: 4 specimens, voxel size, 15 µm) collected from the Labrador Sea and Baffin Bay deep-water basins, Eastern Canadian Arctic. These data provide reference models useful for developing methods to assess structural integrity and other fine-scale complexities in many biological, geological, and industrial systems. This will be of wider value to those investigating structural composition, arrangement and/or composition of complex architecture within the fields and subdisciplines of biology, ecology, medicine, environmental geology, and structural engineering.
Topics: Anthozoa; Animals; X-Ray Microtomography; Imaging, Three-Dimensional; Canada
PubMed: 38849366
DOI: 10.1038/s41597-024-03396-9 -
Molecular Phylogenetics and Evolution Jun 2024Sea anemones (Order Actiniaria) are a diverse group of marine invertebrates ubiquitous across marine ecosystems. Despite their wide distribution and success, a knowledge...
Sea anemones (Order Actiniaria) are a diverse group of marine invertebrates ubiquitous across marine ecosystems. Despite their wide distribution and success, a knowledge gap persists in our understanding of their diversity within tropical systems, owed to sampling bias of larger and more charismatic species overshadowing cryptic lineages. This study aims to delineate the sea anemone diversity in Mo'orea (French Polynesia) with the use of a dataset from the Mo'orea Biocode's "BioBlitz" initiative, which prioritized the sampling of more cryptic and understudied taxa. Implementing a target enrichment approach, we integrate 71 newly sequenced samples into an expansive phylogenetic framework and contextualize Mo'orea's diversity within global distribution patterns of sea anemones. Our analysis corroborates the presence of several previously documented sea anemones in French Polynesia and identifies for the first time the occurrence of members of genera Andvakia and Aiptasiomorpha. This research unveils the diverse sea anemone ecosystem in Mo'orea, spotlighting the area's ecological significance and emphasizing the need for continued exploration. Our methodology, encompassing a broad BLAST search coupled with phylogenetic analysis, proved to be a practical and effective approach for overcoming the limitations posed by the lack of comprehensive sequence data for sea anemones. We discuss the merits and limitations of current molecular methodologies and stress the importance of further research into lesser-studied marine organisms like sea anemones. Our work sets a precedent for future phylogenetic studies stemming from BioBlitz endeavors.
PubMed: 38849066
DOI: 10.1016/j.ympev.2024.108118 -
PloS One 2024Describing the structural complexity of seabeds is of primary importance for a number of geomorphological, hydrodynamical and ecological issues. Aiming to bring a...
Describing the structural complexity of seabeds is of primary importance for a number of geomorphological, hydrodynamical and ecological issues. Aiming to bring a decisive insight on the long-term development of a unified view, the present study reports on a comparative multi-site analysis of high resolution topography surveys in rough nearshore environments. The nine study sites have been selected to cover a wide variety of topographical features, including rocky and coral seabeds. The topography data has been processed to separate roughness and bathymetry-related terrain features, allowing to perform a comprehensive spectral and statistical analysis of each site. A series of roughness metrics have been tested to identify the most relevant estimators of the bottom roughness at each site. The spectral analysis highlights the systematic presence of a self-affine range of variable extension and spectral slope. The standard deviation of the seabed elevation varies from 0.04 to 0.77 m. The statistical and multi-scale analysis performed on the whole set of roughness metrics allows to identify connection between metrics and therefore to propose a reduced set of relevant roughness estimators. A more general emphasis is placed on the need to properly define a unified framework when reconstructing roughness statistics and bathymetry from fine seabed topographical data.
Topics: Anthozoa; Animals; Geologic Sediments; Ecosystem
PubMed: 38843131
DOI: 10.1371/journal.pone.0303422 -
Scientific Reports Jun 2024Deep-sea coral assemblages are marine biodiversity hot spots. Because of their life history traits, deep-sea corals are highly vulnerable to the impacts of human...
Deep-sea coral assemblages are marine biodiversity hot spots. Because of their life history traits, deep-sea corals are highly vulnerable to the impacts of human activities such as fishing. The critically endangered "bamboo coral" Isidella elongata is a key structuring species of deep muddy bottoms that is susceptible to habitat destruction, particularly from trawling. A shallow population of this species was recently discovered by a multibeam and ROV survey offshore of the Asinara Island marine protected area (MPA) (northwestern Sardinia, NW Mediterranean Sea). This vulnerable marine assemblage has been found under healthy conditions at depths ranging from 110 to 298 m. Isidella elongata occurs on a muddy seafloor locally characterised by boulders associated with black coral species (Parantipathes larix and Antipathes dichotoma). The lush colonies of I. elongata seem to be related to natural protection from bottom trawling activity; nevertheless, the presence of lost fishing artisanal nets has been observed in the study area. These structuring species are indicators of vulnerable marine ecosystems, and their conservation is essential for preserving marine biodiversity. Therefore, enlarging the perimeter of the Asinara Island MPA into its deeper western waters is suggested to ensure the protection of these valuable and vulnerable marine ecosystems.
Topics: Animals; Mediterranean Sea; Anthozoa; Biodiversity; Conservation of Natural Resources; Italy; Islands; Ecosystem; Fisheries
PubMed: 38834719
DOI: 10.1038/s41598-024-63652-1 -
Scientific Reports Jun 2024Reef-building corals live in highly hydrodynamic environments, where water flow largely controls the complex chemical microenvironments surrounding them-the...
Reef-building corals live in highly hydrodynamic environments, where water flow largely controls the complex chemical microenvironments surrounding them-the concentration boundary layer (CBL). The CBL may be key to alleviate ocean acidification (OA) effects on coral colonies by partially isolating them. However, OA effects on coral CBL remain poorly understood, particularly under different flow velocities. Here, we investigated these effects on the reef-building corals Acropora cytherea, Pocillopora verrucosa, and Porites cylindrica. We preconditioned corals to a control (pH 8.0) and OA (pH 7.8) treatment for four months and tested how low flow (2 cm s) and moderate flow (6 cm s) affected O and H CBL traits (thickness, surface concentrations, and flux) inside a unidirectional-flow chamber. We found that CBL traits differed between species and flow velocities. Under OA, traits remained generally stable across flows, except surface pH. In all species, the H CBL was thin and led to lower surface pH. Still, low flow thickened H CBLs and increased light elevation of surface pH. In general, our findings reveal a weak to null OA modulation of the CBL. Moreover, the OA-buffering capacity by the H CBL may be limited in coral species, though low flow could enhance CBL sheltering.
Topics: Anthozoa; Animals; Hydrogen-Ion Concentration; Oxygen; Seawater; Oceans and Seas; Coral Reefs; Water Movements; Ocean Acidification
PubMed: 38830941
DOI: 10.1038/s41598-024-63210-9 -
PeerJ 2024Rainfall-induced coastal runoff represents an important environmental impact in near-shore coral reefs that may affect coral-associated bacterial microbiomes. Shifts in...
BACKGROUND
Rainfall-induced coastal runoff represents an important environmental impact in near-shore coral reefs that may affect coral-associated bacterial microbiomes. Shifts in microbiome community composition and function can stress corals and ultimately cause mortality and reef declines. Impacts of environmental stress may be site specific and differ between coral microbiome compartments (., tissue mucus). Coastal runoff and associated water pollution represent a major stressor for near-shore reef-ecosystems in Guam, Micronesia.
METHODS
colonies growing on the West Hagåtña reef flat in Guam were sampled over a period of 8 months spanning the 2021 wet and dry seasons. To examine bacterial microbiome diversity and composition, samples of tissue and mucus were collected during late April, early July, late September, and at the end of December. Samples were collected from populations in two different habitat zones, near the reef crest (farshore) and close to shore (nearshore). Seawater samples were collected during the same time period to evaluate microbiome dynamics of the waters surrounding coral colonies. Tissue, mucus, and seawater microbiomes were characterized using 16S DNA metabarcoding in conjunction with Illumina sequencing. In addition, water samples were collected to determine fecal indicator bacteria (FIB) concentrations as an indicator of water pollution. Water temperatures were recorded using data loggers and precipitation data obtained from a nearby rain gauge. The correlation structure of environmental parameters (temperature and rainfall), FIB concentrations, and microbiome diversity was evaluated using a structural equation model. Beta diversity analyses were used to investigate spatio-temporal trends of microbiome composition.
RESULTS
microbiome diversity differed between tissues and mucus, with mucus microbiome diversity being similar to the surrounding seawater. Rainfall and associated fluctuations of FIB concentrations were correlated with changes in tissue and mucus microbiomes, indicating their role as drivers of microbiome diversity. tissue microbiome composition remained relatively stable throughout dry and wet seasons; tissues were dominated by , coral endosymbionts and putative indicators of coral health. In nearshore tissue microbiomes, , putative obligate coral endosymbionts, were more abundant than in colonies growing near the reef crest (farshore). mucus microbiomes were more diverse during the wet season than the dry season, a distinction that was also associated with drastic shifts in microbiome composition. This study highlights the seasonal dynamics of coral microbiomes and demonstrates that microbiome diversity and composition may differ between coral tissues and the surface mucus layer.
Topics: Animals; Anthozoa; Microbiota; Seasons; Coral Reefs; Mucus; Seawater; Bacteria
PubMed: 38827308
DOI: 10.7717/peerj.17421