Reef Structure Research Articles

Conceptualizing D-Honeycomb Artificial Coral Reef Structure (DHARS) through Stoneware Ceramic Artwork

The Artificial Reef Structure D-Honeycomb (DHARS) is a study that reflects the design needs of natural coral reefs. It focuses on ceramic material (stoneware) that can invertebrate, penetrate and grow on natural corals. It will theoretically allow corals to bounce back faster with the structural analysis of Dual-Honeycomb. Overall, DHARS offers simple, effective and inexpensive design structures for artificial coral reefs that are important for the underwater environment and remote island communities where they need them for their habitat. Keywords: Stoneware ceramic; Artificial Coral Reef; Honeycomb eISSN: 2398-4287 © 2022. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open access article under the CC BYNC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia. DOI: https://doi.org/10.21834/ebpj.v7iSI7%20(Special%20Issue).3779

Microfacies analysis and depositional environment of the Upper Cretaceous rocks in Tang‐e Vanak section (Central Zagros Basin, SW Iran)

The Tarbur Formation is a carbonate stratigraphic unit in the Zagros Basin. This formation is exposed between the Main Zagros Reverse and High Zagros faults and Sabzpoushan Fault. In this study, we describe the depositional characteristics of the Upper Cretaceous sediments (Tarbur Formation) in the Tang‐e Vanak section. In this section, the lower conglomeratic boundary below the Tarbur Formation is named the Amiran Formation and the upper boundary of the Tarbur Formation is disconformably overlain by white dolomitic deposits of the Shahbazan Formation. The Tarbur Formation was interpreted to be deposited in a carbonate homoclinic ramp due to the lack of a deep lagoon environment in the back of the reef structures and the turbidity sediments in its frontal margin. Based on this study, 8 microfacies were recognized including (1) Algal‐foraminiferal wackestone/packstone (2) Bioclastic‐ algal wackestone/packstone, (3) Intraclast bioclastic packstone, (4) Coral boundstone, (5) Rudist boundstone, (6) Bioclastic grainstone, (7) Bioclastic‐foraminiferal wackestone, and (8) Planktonic foraminiferal intraclastic wackestone/packstone. These microfacies were located in the inner, middle, and outer ramp.

Spatial distribution patterns of coral reefs in the Abrolhos region (Brazil, South Atlantic ocean)

Managers and scientists benefit from satellite-derived bottom type maps of coral reefs and other highly biodiverse coastal ecosystems. Here, we generated a map of the coral reefs within the Abrolhos National Marine Park (ANMP), one of Brazil’s most iconic marine protected areas, using a very-high-spatial-resolution WorldView-2 (WV02) image and field observations. A particular geomorphology characterizes this region, where reefs grow in columnar pinnacles with different top height and dimensions (1–25 m height and 1–50 m diameter). The WV02 image went through three different processing steps (corrections for atmosphere, sun-glint and water column effects) to retrieve the bottom signal at 478 nm, which was used to produce a bottom map from an object-based image analysis (OBIA) and to evaluate reef distribution through landscape metrics. A bottom map with 64% of overall accuracy was obtained. Reef distribution showed a heterogeneous aggregation pattern of pinnacles to the East of the Abrolhos archipelago as well as the vegetated bottom around the archipelago. The novel map presented herein may guide management strategies of the AMNP, provide a background for connectivity studies, and help address the evolution (i.e., biogeomorphology processes) of the unique shallow Abrolhos reef structures.

Seq' and ARMS shall find: DNA (meta)barcoding of Autonomous Reef Monitoring Structures across the tree of life uncovers hidden cryptobiome of tropical urban coral reefs.

Coral reefs are among the richest marine ecosystems on Earth, but there remains much diversity hidden within cavities of complex reef structures awaiting discovery. While the abundance of corals and other macroinvertebrates are known to influence the diversity of other reef-associated organisms, much remains unknown on the drivers of cryptobenthic diversity. A combination of standardized sampling with 12 units of the Autonomous Reef Monitoring Structure (ARMS) and high-throughput sequencing was utilized to uncover reef cryptobiome diversity across the equatorial reefs in Singapore. DNA barcoding and metabarcoding of mitochondrial cytochrome c oxidase subunit I, nuclear 18S and bacterial 16S rRNA genes revealed the taxonomic composition of the reef cryptobiome, comprising 15,356 microbial ASVs from over 50 bacterial phyla, and 971 MOTUs across 15 metazoan and 19 non-metazoan eukaryote phyla. Environmental factors across different sites were tested for relationships with ARMS diversity. Differences among reefs in diversity patterns of metazoans and other eukaryotes, but not microbial communities, were associated with biotic (coral cover) and abiotic (distance, temperature and sediment) environmental variables. In particular, ARMS deployed at reefs with higher coral cover had greater metazoan diversity and encrusting plate cover, with larger-sized non-coral invertebrates influencing spatial patterns among sites. Our study showed that DNA barcoding and metabarcoding of ARMS constitute a valuable tool for quantifying cryptobenthic diversity patterns and can provide critical information for the effective management of coral reef ecosystems.

A Review of the Ecosystem Services Provided by the Native Oyster (Ostrea edulis): Implications for Restoration

Native oyster (Ostrea edulis) habitat has been decimated across the majority of its natural range as a result of human activity. In recent decades, oyster restoration projects have gathered increasing support due to their potential to provide ecosystem services that offset increasing pressure from human development, resource demand, and also climate change. These ecosystem services are reviewed here, so as to inform the potential benefit of restoration projects. Ecosystem services can be divided into four categories: provisioning services through direct utilisation of oysters and the species they support, regulating services that help maintain a healthy environment, habitat services that benefit biodiversity, and cultural services that can influence tourism and wider cultural values. Ecosystem services are often interlinked in complex networks, though these can be linked back to two overarching ecosystem functions, stemming from either the filter feeding activity of oysters, or the physical reef structure that they provide. The MARINEFF oyster enhancement reefs installed in the Solent, September 2020, are intended to support the extensive Solent Oyster Restoration Project initiated by the Blue Marine Foundation. The expectation is that they will facilitate both oyster settlement and the release of larvae for the repopulation of the Solent system. This may contribute to the recovery of ecosystem services mentioned in this review. It is important to note however that there is a lack of baseline data for native oysters, and the ecosystem service values they provide are poorly constrained, meaning that ecosystem service estimates are derived largely from other species of oyster. This inhibits our ability to accurately calculate and model natural capital provided by native oysters, highlighting the necessity for further research so as to inform management and restoration targets.

ГЕОДИНАМІКА

Purpose. The objective of this study is the investigation of the Silurian-Lower Devonian (Lochkovian) carbonate-clay sedimentary complex of the southwestern slope of the East-European platform. Its formation was the result of a single cycle of geodynamic and sedimentary events in the lithological record of the southern continental margin of Baltica. Methodology. The study is based on well-logs correlation, lithological and geochemical investigations of core samples, and petrographic thin sections analysis. The obtained results were used to establish patterns of changes in the material composition of the studied strata in time and space in order to determine the basin development dynamics of the continental margin of the Eastern European platform southwestern slope in the Silurian-Early Devonian. Results. It is established that the formation of the carbonate-clay sequence represents a single sedimentary cycle and was the result of a complex of geodynamic, depositional and paleoclimatic events that took place on the Baltica southern continental margin. The Silurian period was characterized by intensive development of benthic organisms and reef structure formation in the proximal part of the basin and clay-carbonate muds enriched with dispersed organic matter in its distal part. In the Early Devonian, carbonate biogenic sedimentation continued throughout the basin. The carbonate maximum content (80–98%) proves the existence of the reef constructions in the basin sedimentary record. Lower values of carbonate content are characteristic of marls (40–55%) and biodetritic limestones (56–75%), which make up the main part of the Silurian sequence. There are no reef constructions in the section of the Lochkovian stage of Devonian, and the calcium carbonate content in the rocks varies from 45 to 83%. The content of CaCO3 in mudstones and calcareous mudstones of the Silurian varies from 5 to 15%. Originality. The applied complex of lithological, geochemical, geological-geophysical and paleogeographic investigations allowed studying the sedimentary basin dynamics in the Silurian-Early Devonian with the assessment of the possibility of participation of these strata in oil and gas hydrocarbons generation. Practical significance. The obtained results show that the carbonate-clay complex of sedimentary rocks of the Silurian and Lower Devonian (Lochkovian) of the studied region can be considered as a separate petroleum system, including source rocks, reservoir rocks and possible conventional and unconventional oil and gas accumulations.

FISH OTOLITHS AND FORAMINIFERA FROM THE BORSKÝ MIKULÁŠ SECTION (SLOVAKIA, MIDDLE MIOCENE, UPPER BADENIAN, VIENNA BASIN) AND THEIR PALEOENVIRONMENTAL SIGNIFICANCE

Thirty-eight otolith-based species of fishes and 41 foraminifera species have been recorded in the Borský Mikuláš-Vinohrádky section in the upper Badenian deposits in the eastern part of the Vienna Basin, in West Slovakia. Two new species of otoliths are introduced here: Thorogobius antirostratus n. sp. and Gerres mlynskyi n. sp. Among the foraminifera Biasterigerina planorbis and Elphidium crispum associated with other elphidiids, Lobatula lobatula and Cibicides crassiseptatum prevail. Overall, the family of Gobiidae dominate in the assemblage of otoliths (>90 % of specimens). Meso- and epipelagial fishes or diversified gadids and sciaenids are missing. From the molluscs, the first record of Aturia sp. in the Borský Mikuláš section is observed. Otoliths and foraminifera document a normal marine environment of well-aerated shallow water with a depth of 30-50 metres, with muddy to sandy bottoms of marine meadows and plenty of light in the subtropical climatic conditions. Several fish genera (for example Gerres) give evidence for the nearness of reef structures. There are no species (excepting Lesueurigobius vicinalis) in common with the known Lower Serravallian otolith fauna from the Eastern Paratethys. Some species from the Borský Mikuláš-Vinohrádky section can also be found in the Mediterranean Langhian-Serravallian interval and are interpreted as a relic of the lower Badenian (Langhian) fish assemblages.

Bleaching Susceptibility and Resistance of Octocorals and Anemones at the World's Southern-Most Coral Reef.

Coral reefs are amongst the most biodiverse ecosystems on earth, and while stony corals create the foundational complexity of these ecosystems, octocorals and anemones contribute significantly to their biodiversity and function. Like stony corals, many octocorals contain Symbiodiniaceae endosymbionts and can bleach when temperatures exceed the species’ upper thermal limit. Here, we report octocoral bleaching susceptibility and resistance within the subtropical Lord Howe Island coral reef ecosystem during and after marine heatwaves in 2019. Octocoral and anemone surveys were conducted at multiple reef locations within the Lord Howe Island lagoon during, immediately after, and 7 months after the heatwaves. One octocoral species, Cladiella sp. 1, experienced bleaching and mortality, with some bleached colonies detaching from the reef structure during the heatwave (presumed dead). Those that remained attached to the benthos survived the event and recovered endosymbionts within 7 months of bleaching. Cladiella sp. 1 Symbiodiniaceae density (in cells per µg protein), chlorophyll a and c 2 per µg protein, and photosynthetic efficiency were significantly lower in bleached colonies compared to unbleached colonies, while chlorophyll a and c 2 per symbiont were higher. Interestingly, no other symbiotic octocoral species of the Lord Howe Island lagoonal reef bleached. Unbleached Xenia cf crassa colonies had higher Symbiodiniaceae and chlorophyll densities during the marine heatwave compared to other monitoring intervals, while Cladiella sp. 2 densities did not change substantially through time. Previous work on octocoral bleaching has focused primarily on gorgonian octocorals, while this study provides insight into bleaching variability in other octocoral groups. The study also provides further evidence that octocorals may be generally more resistant to bleaching than stony corals in many, but not all, reef ecosystems. Responses to marine heating events vary and should be assessed on a species by species basis.

A stratified transect approach captures reef complexity with canopy-forming organisms

On the Great Barrier Reef (GBR), persistent changes to reef communities have begun to be documented, and on inshore reefs these shifts may favour the proliferation of macroalgae. Critical to understanding changes to reef community structure in response to anthropogenic impacts is developing effective methods to accurately document the abundance of different reef organisms. Effective monitoring must be time and cost efficient, replicable, and able to sufficiently and accurately detect disturbances to allow development of strategies to mitigate their impacts. Traditional techniques to document coral reef communities (i.e. photo-quadrats, benthic intercept transects) rely on planar views, which tend to either over- or under-represent canopy-forming organisms. As canopy-forming organisms are likely to be affected by anthropogenic influences (corals negatively, algae positively), it is essential for monitoring programs to implement methods sufficient to document changes to the vertical dimension of coral reefs. Here we build on previous work to document the canopy effect in coral-dominated ecosystems and propose a new survey approach suitable for implementation in algal-dominated systems. A vertically stratified transect, modified from a traditional point intercept transect, captures benthic and canopy-forming members of reef communities and provides information on three-dimensional complexity. To test the capability of the new method to detect changes in vertical reef structure, seaweed was removed from experimental quadrats and monitoring techniques were applied before and after four months of regrowth. A stratified method more accurately captured the three-dimensional change resulting from algal canopy growth, while resolving the over- and under-representation of algal biomass in two traditional techniques. We propose that a stratified transect method improves abundance estimates of canopy-forming organisms whilst maintaining data compatibility with traditional methods.

Study on flow field characteristics of box artificial reef

Based on Zhuhai Miaowan artificial reef demonstration project, this paper studied the flow field characteristics of single box artificial reef and reef group under different spacing by using computational fluid dynamics (CFD) method. The results show that the box artificial reef has a significant effect on flow field. The maximum upwelling height near the reef is about 1.4 times the reef height, and the length of the back vortex is twice the reef size. In the reef group arrangement, the flow field distribution plays the best performance at the 5m spacing arrangement. The research results can provide guidance for reef structure optimization and practical arrangement in site.

Evaluation of slim-hole NMR logging for hydrogeologic insights into dolostone and sandstone aquifers

This study assesses the performance and limitations of slim-hole borehole nuclear magnetic resonance (NMR) technology from a hydrogeologic perspective in fractured, porous rock. NMR logging was carried out in dolomitic and sandstone bedrock boreholes at two research test sites in Ontario, Canada, where aquifer and aquitard units provide a range of clay contents as well as a variety of primary and secondary porosity types (e.g. discrete fractures, reefal structures, vugs and karstic conduits). Results were compared to core measurements, geophysical logs, and hydrogeophysical testing. The vertical response curve of the instrument tested was found to produce 60% of the signal from within a 0.2m span surrounding the measuring point. The repeatability of the total porosity measurements in stationary mode is excellent where the porosity is greater than 0.15. Below that threshold, repeatability is scattered at ±0.05 porosity about the mean, with the variability primarily within the clay- and capillary-bound fractions. The NMR porosity estimates agreed with core measurements to within ±0.04 porosity in both the dolostone and sandstone, but the correlation deteriorates in finely bedded lithologies, and where fracturing is present. Much of the discrepancy is attributed to scaling in a finely layered geologic sequence, as the core samples are much smaller than the entire volume measured with NMR probes. Data collection with the probe in motion (continuous logging) added variability to the response when compared to stationary recordings. Although broadscale trends were comparable, the details and depth-specific insights of the bound fluid fractions varied with logging rates. Overall, NMR provides a robust measurement of the bulk matrix porosity and pore size distribution of lithologies intersected, both of which are critically important parameters in understanding hydrogeologic conditions and contaminant distributions in layered sedimentary rock systems.

Living on the edge: environmental variability of a shallow late Holocene cold-water coral mound

Similar to their tropical counterparts, cold-water corals (CWCs) are able to build large three-dimensional reef structures. These unique ecosystems are at risk due to ongoing climate change. In particular, ocean warming, ocean acidification and changes in the hydrological cycle may jeopardize the existence of CWCs. In order to predict how CWCs and their reefs or mounds will develop in the near future one important strategy is to study past fossil CWC mounds and especially shallow CWC ecosystems as they experience a greater environmental variability compared to other deep-water CWC ecosystems. We present results from a CWC mound off southern Norway. A sediment core drilled from this relatively shallow (~ 100 m) CWC mound exposes in full detail hydrographical changes during the late Holocene, which were crucial for mound build-up. We applied computed tomography, 230Th/U dating, and foraminiferal geochemical proxy reconstructions of bottom-water-temperature (Mg/Ca-based BWT), δ18O for seawater density, and the combination of both to infer salinity changes. Our results demonstrate that the CWC mound formed in the late Holocene between 4 kiloannum (ka) and 1.5 ka with an average aggradation rate of 104 cm/kiloyears (kyr), which is significantly lower than other Holocene Norwegian mounds. The reconstructed BWTMg/Ca and seawater density exhibit large variations throughout the entire period of mound formation, but are strikingly similar to modern in situ observations in the nearby Tisler Reef. We argue that BWT does not exert a primary control on CWC mound formation. Instead, strong salinity and seawater density variation throughout the entire mound sequence appears to be controlled by the interplay between the Atlantic Water (AW) inflow and the overlying, outflowing Baltic-Sea water. CWC growth and mound formation in the NE Skagerrak was supported by strong current flow, oxygen replenishment, the presence of a strong boundary layer and larval dispersal through the AW, but possibly inhibited by the influence of fresh Baltic Water during the late Holocene. Our study therefore highlights that modern shallow Norwegian CWC reefs may be particularly endangered due to changes in water-column stratification associated with increasing net precipitation caused by climate change.

Bottom Drag Coefficient on a Shallow Barrier Reef

AbstractThe present paper reports of a field experiment over a shallow, roughness‐varying barrier reef at Maupiti island, French Polynesia. The depth‐averaged momentum balance is used to estimate the bottom drag coefficient Cd, which varies from 0.01 to 0.3, with dependence on both depth and reef structure. The depth effect on Cd is well predicted by a log dependency, as used in previous laboratory and fields observations. The present results extend the approach to a system with more wave exposure and higher roughness‐to‐depth ratio. Additionally, the statistical relationship between high‐resolution reef topography and hydrodynamical parameters is discussed.

Species Delimitation of Hexacorallia and Octocorallia Around Iceland Using Nuclear and Mitochondrial DNA and Proteome Fingerprinting

Cold-water corals build up reef structures or coral gardens and play an important role for many organisms in the deep sea. Climate change, deep-sea mining, and bottom trawling are severely compromising these ecosystems, making it all the more important to document the diversity, distribution, and impacts on corals. This goes hand in hand with species identification, which is morphologically and genetically challenging for Hexa- and Octocorallia. Morphological variation and slowly evolving molecular markers both contribute to the difficulty of species identification. In this study, a fast and cheap species delimitation tool for Octocorallia and Scleractinia, an order of the Hexacorallia, of the Northeast Atlantic was tested based on 49 specimens. Two nuclear markers (ITS2 and 28S rDNA) and two mitochondrial markers (COI and mtMutS) were sequenced. The sequences formed the basis of a reference library for comparison to the results of species delimitation based on proteomic fingerprinting using MALDI-TOF MS. The genetic methods were able to distinguish 17 of 18 presumed species. Due to a lack of replicates, using proteome fingerprinting only 7 species were distinguishable. Species that could not be distinguished from one another still achieved good signals of spectra but were not represented by enough specimens for comparison. Therefore, it is predicted that with an extensive reference library of proteome spectra for Scleractinia and Octocorallia, MALDI-TOF MS may provide a rapid and cost-effective alternative for species discrimination in corals.

Oyster Reef Surfaces in the Central Wadden Sea: Intra-Reef Classification and Comprehensive Statistical Description

The Pacific oyster (Magallana gigas) is an invasive species in the Wadden Sea transforming parts of it permanently. M. gigas, as an ecosystem engineer, builds reef structures that are characterized by highly complex and variable surfaces consisting of densely packed, sharp-edged individuals connected with cement-like bonds. To investigate the interactions between reef structure, shape and formation and wave as well as tidal currents, an understanding of the surface roughness is essential. This work reports on observations of oyster reefs for which seven new structural classes (Central Reef, Transitional Zone, Cluster I, Cluster II, Patch I, Patch II, and Garland) are proposed. For each class, high resolution Digital Elevation Models (DEMs) have been elaborated based on Structure-from-Motion (SfM) photogrammetry and analyzed using spatial statistics. By determining probability density functions (PDFs), vertical porosity distributions, abundances, orientations and second-order structure functions (SSFs), topographical parameters that influence the hydraulic bed roughness have been determined. The results suggest, that by applying the structural classification and their distinct topographical roughness parameters, the oyster reef surfaces can be described appropriately accounting for their complexity. The roughness accounts to a total roughness height kt = 103 ± 15 mm and root-mean-square roughness height krms = 23 ± 5 mm. These values were found similar across all structural classes, yet the shape of the PDFs reveal differences. With decreasing abundance, the distributions become more positively skewed and are characterized by more extreme outliers. This is reflected in the higher statistical moments, as the skewness ranges between Sk = 0.4–2.1 and the kurtosis between Ku = 2.2–11.5. The analysis of the orientations and the SSFs confirms anisotropic behavior across all structural classes. Further, the SSFs reveal the oyster shells as significant roughness elements with exception of Cluster I and II, where the clusters are identified as significant roughness elements. The provided set of topographical roughness parameters enhances the knowledge of oyster reef surfaces and gives insights into the interactions between biogenic structure and surrounding hydrodynamics. The new intra-reef classification allows for more accurate determination of the overall roughness as well as the population dynamics of the habitat forming oyster. Combined with hydraulic measurements, the results can be used to estimate the hydraulic bed roughness induced by the oyster reef surfaces.

Wave attenuation prediction of artificial coral reef using machine-learning integrated with hydraulic experiment

Various prevention methods have been proposed to resolve such coastal erosion problems, known as an important social issue in many countries. However, most of the methods designed and constructed involve gravity-type structures, causing various problems such as the obstruction of seawater circulation and changes in water quality and marine ecosystem. In this study, we propose an eco-friendly artificial coral reef structure that can control coastal erosion and help preserve the coastal environment. We investigated the wave height distribution and energy reduction characteristics through a two-dimensional hydraulic model experiment under various conditions, including different external force conditions (wave height, water depth, and wave period) and design conditions (dimensionless crown width and submergence ratio). Furthermore, we investigated the drift sand control and morphological characteristics of artificial coral reefs through a movable bed experiment. The results of the hydraulic experiment revealed that the dimensionless crown width and submergence ratio factors had a dominant effect on the wave height attenuation. In addition, the artificial coral reef structures outperformed broadly applied tetrapod structures in terms of coastline advancement and seabed protection under storm wave conditions. Moreover, to estimate the wave attenuation characteristics of artificial coral reefs, we introduced a prediction study of wave attenuation characteristics of artificial coral reefs to propose an explicit method composed of weights and biases using modified artificial neural network. We found that the method of calculating the wave dissipation coefficient calculated with the presented weight and bias matrix shows more accurate reliability than the calculation method based on the existing empirical formula.

Visualization of Coral Reef Cover with Photogrammetry Method at Coastal Waters of Lemon Island, Manokwari, Indonesia

Lemon Island waters are an island that has a diversity of coral reef ecosystems. The coastal areas of Lemon Island have different coral reef structures, so it is necessary to conduct research using underwater photogrammetry to visualize the condition of coral reefs. Photogrammetry is a process of obtaining information about an object through measurements made from photographs. The use of underwater photogrammetry in visualizing coral reefs can also be used to extract coral conditions such as size, condition, and percentage of coral colony cover. This study aims to determine the shape and condition of the visual life form of coral reefs in the waters of Lemon Island. The method used in this research is the photogrammetric method which is then analyzed using CPCe, using the number of random points used to analyze 30 photos for each frame. Based on the results obtained, it can be seen 6 forms of coral growth found in the waters of Lemon Island, namely, Acropora Branching, Acropora Submassive, Coral Branching, Coral Massive, Coral Submassive and Coral Mushroom. The total percentage of coral reef cover is 45.84%, so it is categorized in moderate condition.

Private Capital to Improve Nature-Based Solutions for Coastal Protection: Time for a Boost

Coastal protection, an important coral reef ecosystem service, is threatened by increasing coral mortality, exacerbated by global climate change. Nature-based solutions in the form of coral restoration, while not perfect, can assist in rebuilding reef structure and improving the flow of the service for some sites. With a financing gap existing between what is required for conservation and what is being accessed, private investors should be playing a larger role in such restoration activities. Especially so as coastal hoteliers in particular, benefit from stable beaches and also have additional income generating potential with healthy reefs. Blended finance solutions in particular, are especially suited to restoration that incorporates substrate addition, while payments for ecosystem services are more suited to coral gardening. Conservation and finance practitioners must engage further and understand each other’s worlds, in order for these private sources to be effectively sourced and utilized.

FEATURES OF THE BIOLOGY OF THE POLYCHETE <i>FICOPOMATUS ENIGMATICUS</i> (FAUVEL, 1923) FROM MASS SETTLEMENTS IN THE COASTAL WATERS OF THE KERCH STRAIT (BLACK SEA)

In September 2019, the polychaeta (Fauvel, 1923), formerly known as Fauvel, 1923, was found in mass colonial settlements in the coastal waters of the Kerch Strait near the Arshintsevskaya Spit. Some workers believe that the original natural distribution of this polychaeta was in brackish water bodies of India. This species is currently known to be widely distributed along the coasts of the Atlantic, Pacific, and Indian Oceans, and of the North, Mediterranean, and Caspian Seas. Only a few isolated individuals of have been found so far along the Crimean coast of the Black Sea, in the coastal zone of Sebastopol and along the Karadag shores. The colonies described in this study do not constitute reef structures yet but have already reached high population numbers. The colony have a diameter of 46 cm and comprise 1774 individuals. The settlements of are true populations represented by individuals of different sizes ranging in length from 2 to 39 mm. The populations include both males and females: males comprise 56% and females 44% of the population. The fecundity of the worms expressed as the number of mature eggs per female depends on the body size and ranges from 5800 eggs for the body size of 12 mm to 24820 eggs for the body size of 29 mm. The present study described the morphology of using scanning electron microscopy and identified numerous sensory structures on the surface of the body, gills and the pygidium for the first time. Judging from the presence of a mass settlement of the polychaeta in the coastal waters of the Kerch Strait, it can be presumed that this species has become completely naturalized in the Black Sea. Since this species is eurybiontic, it can be assumed that it will invade the Sea of Azov and adjacent estuaries, river deltas and coastal lakes successfully, which will have an inevitable effect on the life of the local species and the ecosystems in general.

Drivers of fine-scale diurnal space use by a coral-reef mesopredatory fish.

The habitat preferences of many reef fishes are well established, but the use of space within these habitats by non-site-attached species is poorly studied. The authors examined the space use of a functionally important mesopredator, graysby (Cephalopholis cruentata), on six patch reefs in the Florida Keys. A 1m2 -scale grid was constructed on each reef and 16 individual C. cruentata were tracked diurnally in situ to identify space use. At the patch reef scale, larger C. cruentata were more active and had larger observed home ranges, although home ranges were also affected by fish density and the abundances of prey and predators. The total time in each 1 m2 grid cell was regressed against a range of fine-scale biotic variables, including multiple variables derived from structure-from-motion three-dimensional digital reconstructions of each reef. Nonetheless, time in grid cells (preferred microhabitats) was only significantly positively correlated with the height of carbonate structures, likely because the cavities they enclose are particularly suitable for predator avoidance, resting and ambushing prey. The ongoing flattening of reefs in the region caused by negative carbonate budgets is thus likely to have significant effects on the abundance and space use of C. cruentata. In addition to examining spatial patterns, we analysed C. cruentata waiting times in each grid cell before moving. These times were best approximated by a truncated power-law (heavy-tailed) distribution, indicating a "bursty" pattern of relatively long periods of inactivity interspersed with multiple periods of activity. Such a pattern has previously been identified in a range of temperate ambush predators, and the authors extend this move-wait behaviour, which may optimize foraging success, to a reef fish for the first time. Understanding how C. cruentata uses space and time is critical to fully identify their functional role and better predict the implications of fishing and loss of reef structure.