ACCEPTED ABSTRACTS

Acoustic surveys of insectivorous bird distributions along an elevational gradient on the western coast of Ecuador 

Ryce Hailes(1*), Rebecca Davis(1), Shawn McCracken(1,2) 

(1)Department of Life Sciences, College of Science, Texas A&M University-Corpus Christi; (2)Third Millennium Alliance 

          The Pacific Forest, situated along the western coast of Ecuador, is home to a range of forest types, from tropical dry to rainy cloud forests, with elevations reaching 650 meters. The deciduous dry forest receives annual precipitation of 100-200 cm, the wet forest receives >200 cm, and the cloud forest receives >450 cm. This research hopes to look at the movements of insectivorous birds along this elevational and habitat gradient, and how those species distributions change due to rainy or dry seasons, offering insights into how avian species may respond to the changing climate. Currently, the research focuses on two species, the Black-headed antthrush (Formicarius nigricapillus) and the Plain-brown woodcreeper (Dendrocincla fuliginosa). There are four study sites located within the Three Forests Conservation Corridor and Jama-Coaque Ecological Reserve. These sites include a dry forest habitat at 130 m elevation, a wet forest habitat at 396 m, and two cloud forest habitats at 456 m and 632 m, respectively. Audio data from March and October 2020, as well as March and October 2021, are being examined. At each site, an automated recording unit, known as an AudioMoth, was installed, and programmed to record every hour for ten minutes. Once the audio data is uploaded, it is analyzed using Random Forest Models (RFMs) and pattern-matching techniques on the RFCx Arbimon cloud-based acoustic analytic tool. It has been observed that the Black-headed antthrush is moving in response to the changing seasons. Analysis of the woodcreeper movement is currently underway, with similar results expected. 

Keywords: ecology, bioacoustics, biodiversity, species richness, climate change 

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Oysters and opportunities: Creating algorithms and data visualizations for 3D shell characterizations 

Julie Romano(1*), Bright Nnandi(1*), Mehrube Mehrubeoglu(1), Christopher Hollenbeck(2) 

(1)Department of Engineering, College of Engineering and Computer Science, Texas A&M University; (2)Department of Life Sciences, College of Science, Texas A&M University 

          Characterization of 3D objects is challenging when objects lack symmetry and manual measurements of physical attributes, such as surface area and volume, are not feasible. This research focuses on measuring 2D and 3D characteristics of oyster shells from their 3D scans, that are impractical to determine manually. Since oyster shells are a vital component of their ecosystems and economic environments, research on their characterizations is of utmost importance. Thus, 3D structured light scanning is a useful technology to capture measurements without harming the integrity of these irregularly-shaped shells. Previous research has been undertaken for the characterization of limpet shells. This project expands the software capabilities for the use of oyster shells and incorporates additional parameters to be measured from 3D scans, including outer surface area and inner surface area, which had not been developed before for oyster shells. This tool will allow the comparison of physical attributes of oyster shells collected from two different sites along the Texas Gulf Coast. Using 3D scanning and MATLAB programming tools, this research aimed to analyze oyster shell samples and conduct statistical analysis of results with improved MATLAB algorithms. This data will benefit scientists who can then ascertain oyster growth trends based on their sites of origin. The results of this project provide a tool for oyster shell attribute data collection and analysis that can then be used to potentially better understand oysters which are an essential component to the local ecosystem, and to optimize their growing environments. The automated measurement system is presented here as a tool to capture physical attributes of oyster shells. 

Keywords: 3D structured light scanning, engineering tool, environmental science, MATLAB, shell attributes 

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Comparing the bulk skeletal density of corals subjected to changing carbonate chemistries 

Isabelle Morales(1*), David Armstrong(1), Eleanor TenBrink(1), Keisha Bahr(1), Conall McNicholl(2) 

(1)Department of Life Sciences, College of Science, Texas A&M University-Corpus Christi; (2)Hawai'i Institute of Marine Biology, University of Hawai'i at Manoa 

          Coral reefs are essential ecosystems providing support to many marine species. Corals grow complex three-dimensional structures that provide protection for our coastal communities by forming dense skeletons using ions from the seawater. But the continuous release of CO2 into the atmosphere will change our seawater conditions. This change could affect the corals, preventing them from growing as dense impacting the structure services they provide. Therefore, we aim to measure the density of corals exposed to different water chemistries. We predict that if we lower the carbonate the corals will become less dense and if we increase the carbonate then the coral will become denser. Learning about these chemistries’ effects on coral densities is essential to sustain healthy marine ecosystems by providing shelter and protection for the marine species for locals to be able to provide food for their families and helping coastal communities creating barriers from coral reefs to protect coasts from floods and storms. 

Keywords: alkalinity, carbonate chemistries 

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Genetic analysis of the vcg gene for Vibrio vulnificus found in the waters of the Coastal Bend region of Texas 

Brian Kostoch1*, F. Itzanami Valdez(1), Gregory W. Buck(1), Kirk V. Cammarata(1) 

(1)Department of Life Sciences, College of Science, Texas A&M University-Corpus Christi 

          The bacteria Vibrio vulnificus (Vv) is a Gram-negative, pathogenic bacteria that is found in marine environments worldwide. This species of Vibrio was described almost 50 years ago for its ability to not only cause gastrointestinal distress, but also for the high mortality caused by necrotizing fasciitis and sepsis. Distinguishing factors for this increase in virulence include genes such as vvhA, rpoS, the unique 16s rrnA, and the virulence correlated gene (vcg), which is the focus of current research, as little is known about the latter. Previous studies described two major allelic variants, with vcgC being the more clinically prevalent allele and vcgE describing the allele more commonly observed environmentally. The gene encompasses a region of around 495 base pairs in an open reading frame of the same size and is unique to V. vulnificus, as the closest similar gene in another species being V. rotiferianus with around 73% identity. The goal of this project is to optimize primers that could be used for detection of either vcgC or vcgE. Sequencing of locally collected isolates revealed that these bacteria had a moderate range of nucleotide variation of the vcg allele through genomic analysis. Following analysis of variation between isolates, a phylogenetic tree was constructed to compare the respective encoded proteins. Preliminary investigations propose that genomes located within the Coastal Bend region possesses genetic variations not previously described, which may be interest regarding Vv pathogenesis. Further goals are to provide a comprehensive analysis of the vcg locus and its proposed protein that would be further studied for its role in Vv strains causing clinical conditions. 

Keywords: microbiology, bioinformatics, genotypes 

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Limpet shells more resistant to thermal stress on more thermally stressful shores 

Keenan Larriviere(1*), Kinley Cate(1), Chris Bird(1) 

(1)Department of Life Sciences, College of Science, Texas A&M University - Corpus Christi 

          Advancing our understanding of the biology and environmental pressures affecting marine life in a changing world is important to the management and conservation of living marine resources. Hawaiian intertidal patellogastropods (limpets, Cellana spp., ‘opihi) comprise a crashed multispecies fishery and hold substantial cultural value as an important resource. In a range-wide study it was found that the shells of C. exarata are adapted to avoid visual predators, putatively humans, at the expense of thermal tolerance with substantially flattened shells on inhabited islands. Flatter shells have less surface area which reduces their ability to shed heat, like a radiator. Here we investigated the variation in shell morphology with respect to shore type at different locations on a single inhabited island, Maui. ~50 adults were collected from bench (n=8), variable slope (n=4), and boulder shores (n=5) with greater and more effective thermal refuges beneath rocks compared to other shore types. We measured the shell aperture length and width, as well as the spire height and normalized them to the mean length using the allometric growth equation to remove the effect of size on shape. The normalized dimensions were used to estimate the shell surface area using the equation for an elliptical cone. Shells on boulder shores – characterized by the lowest solar irradiance – had shells with significantly less surface area, less massiveness, and more oblong dimensions than those on solid basalt shores. Furthermore, there was significantly more variation in shell shape on stressful bench shores with a greater proportion of tall, round, massive shells, with larger surface areas and thermal dissipation indices. These results indicate that some degree of specialization to thermally extreme conditions exist in a predation-adapted population of C. exarata. Understanding how substratum type affects C. exarata shell morphology is crucial to better manage this resource. 

Keywords: acclimation, adaptation, heat budget, phenotype, adaptive capacity 

 

Understanding biological impacts and recovery timelines for benthic invertebrates following beach nourishment activities in Texas 

Melanie Ponce(1*), Kim Withers(2), Terry Palmer(1), Natasha Breaux(1), Jennifer Beseres Pollack(1) 

(1)Harte Research Institute for Gulf of Mexico Studies; (2)Department of Life Sciences, College of Science, Texas A&M University-Corpus Christi, Texas 

          Beaches are ecologically and economically important coastal habitats. They provide nesting habitat for coastal organisms, host diverse assemblages of benthic invertebrates, support recreation and tourism for coastal communities, and protect private and public property from storms. However, beaches are high-energy environments where sand can erode due to sea level rise, storms, and coastal flooding. One approach to combat beach erosion is “nourishment”, where large quantities of sand are added onto an eroded beach. Despite nourishment being heavily funded, there is a lack of understanding of biological impacts and recovery timelines after nourishment. To assist resource managers tasked with sediment management activities, the effects of nourishment on Texas beaches will be determined using a Before/After, Control/Impact (BACI) study design on two beaches—Jamaica Beach and Sargent Beach—slated for nourishment in the next year. To determine whether differences in benthic communities between reference and nourished beaches can be attributed to nourishment or natural factors, sampling will occur at three reference (control) areas for each nourishment (impact) area. So more robust comparisons can be made between reference and control areas, two nearby reference sites (<10 km from the nourished area) and one distant reference area (>10 km) will be selected for sampling. The nearby reference sites will experience similar hydrological forces to the nourished area and the distant reference areas will ideally be more “pristine” than the close reference areas. Sampling will occur at the nourished and reference beaches every 2 months for at least 10 months prior to a nourishment event. Sediment cores will be used to evaluate macrofauna communities and sediment grain size. Changes in sediments and macrofauna community composition will be determined by univariate and multivariate statistics. To establish guidelines for nourishment activities, these findings will be used to inform resource managers about benthic macroinvertebrate and sediment recovery timelines. 

Keywords: coastal conservation, Texas coast, swash zone, intertidal organisms 

 

Morphological differentiation in two sympatric, reproductively isolated, cryptic populations of a broadcast-spawning shellfish, Cellana exarata 

Kinley Cate(1*), Keenan Larriviere(1), Luz Ángela López De Mesa Agudelo(1,2), Christopher E. Bird(1) 

(1)Department of Life Sciences, College of Science, Texas A&M University – Corpus Christi; (2)Universidad del Valle, Facultad de Ciencias Naturales y Exactas-Biología, Cali, Valle del Cauca, Colombia 

          The endemic Hawaiian limpets (Cellana spp.) are one curious example of adaptively differentiated broadcast-spawning marine invertebrates that diversified within the confines of the Hawaiian archipelago where sympatric speciation cannot be ruled out due to few opportunities for geographic isolation. Two sympatric, cryptic populations of C. exarata were discovered on Maui in 2017 with a small degree of differentiation (FST = 0.03) suggesting a recent split, but there was a substantial degree of reproductive isolation indicating that reinforcement was approaching completion. The hypothesis is that this single species is actually 2 separate, sympatric species with an infertile hybrid that inhabit the same area. By testing for differences in the morphological variation of the two populations, we may be able to identify differential adaptations between the species that contribute to their differential abundances on north and south shores of Maui and assess their contribution to reinforcement, which is the process by which a population splits into two species where there is selection against intermediates because they are adaptively inferior. PCA data collected from the two populations shows diverging characteristics such as shell size, shell height, and thermal dissipation index, hinting at a recent split. The data found in this research can further scientists' and conservationists’ knowledge on the species in general and make more precise action in the formation of rest areas and policymaking regarding the conservation of the species in the area. 

Keywords: cryptic, genetic, conservation, morphology, fisheries 

 

Prevalence of Vibrio in sea spray aerosols during a Saharan dust storm 

Jacqueline Nicolay(1*), Charley Garrett(1), Nicole C. Powers(1), Jeffrey W. Turner(1), Julie Dinasquet(2) 

(1)Department of Life Sciences, College of Science, Texas A&M University-Corpus Christi; (2)Scripps Institute of Oceanography, University of California San Diego 

          Aerosols from sea spray make up the majority of atmospheric particle levels in coastal areas. Sea spray aerosols can act as a vehicle for the transport of bacteria over long distances. Therefore, sea spray could have important implications for public health and the spread of infectious diseases, if pathogenic bacteria can survive and remain viable in sea spray for extended periods of time. Vibrio are a Gram-negative genus of bacteria found in marine environments worldwide, particularly in warmer climates. Although many species are not pathogenic, several species cause illness in humans (e.g., V. parahaemolytics, V. cholerae, V. vulnificus) and marine life (e.g., V. coralliilyticus, V. harveyi, V. anguillarum). Due to climate change and increasing sea surface temperatures, the geographic range of Vibrio is expanding, leading to an increase in cases of Vibrio-associated illness worldwide. Extensive research has increased our understanding of Vibrio in aquatic habitats, but the possibility of atmospheric transport and survival has yet to be determined. The primary objective of this study was to determine if Vibrio could be cultured directly from the atmosphere. Additionally, as Saharan dust storms are known to contribute to marine Vibrio blooms, we investigated the impact of a Saharan dust storm on the prevalence of atmospheric Vibrio. Results demonstrate a direct correlation between presumptive Vibrio colony forming units (CFUs), sulfur dioxide, and particulate matter (PM2.5 and PM10), as well as an inverse correlation between CFUs and nitrogen dioxide. Sea spray transport of Vibrio could have a major impact on its biogeography and further disrupt human and environmental health. 

Keywords: sea spray aerosols, Vibrio, Saharan Air Layer, Saharan dust 

 

Mitochondrial genome of the blackspot snapper, Lutjanus fulviflamma (Perciformes: Lutjanidae), and notes on its phylogeny 

Kevin Labrador(1,2*), Christopher Bird(1), Maybelle Fortaleza(2), Joemarie Lanutan(2), Cleto Nañola Jr.(2) 

(1)Department of Life Sciences, College of Science, Texas A&M University - Corpus Christi, Corpus Christi; (2)Department of Biological Sciences and Environmental Studies, College of Science and Mathematics, University of the Philippines Mindanao

          We report here the complete mitogenome of the blackspot snapper (Lutjanus fulviflamma) collected from Davao Gulf, Southern Mindanao, Philippines. The mitogenome was assembled from 90.6 million reads produced from whole genome shotgun sequencing, 77,187 of which mapped to the reference used in the assembly. The complete mitogenome had a length of 16,512 bp, with 13 protein-coding sequences, 22 transfer RNA, two ribosomal RNA (12S and 16S), and the noncoding control region. The base composition is 28.2% A, 25.1% T, 30.6% C, and 16.1% G, with 46.7% GC content. Protein-coding sequences utilized start and stop codons that were expected for fishes. Phylogenetic analysis shows that the assembled mitogenome was 99.6% identical to the reference L. fulviflamma from Indonesia. The species shared its most recent common ancestor with L. vitta and L. ophuysenii, and formed a cluster with L. russellii, L. carponotatus, and L. ehrenbergii. The mitogenome provides a valuable genomic resource for future phylogenetic and population genetic studies. Meanwhile, the assembly of the whole genome is underway. 

Keywords: mitochondrial genome, next generation sequencing, reef fishes 

 

Developing a molecular assay to genetically differentiate between scalloped hammerhead, Sphyrna lewini, and Carolina hammerhead, Sphyrna gilberti 

Darian Paul(1*), Andrew T. Fields(1), Elizabeth Hunt(1), David S. Portnoy(1) 

(1)Marine Genomics Lab, Department of Life Sciences, College of Science, Texas A&M University – Corpus Christi 

          Global demands for shark fins and meat have led to rapid declines in shark populations, especially in large bodied coastal species such as the hammerhead sharks (Family: Carcharhinidae, Genus: Sphyrna). Management of the scalloped hammerhead (Sphyrna lewini) in the western Atlantic Ocean is challenging due to the existence of a sympatric, externally -morphically identical, cryptic species, the Carolina hammerhead (Sphyrna gilberti) that can hybridize with scalloped hammerheads. Their morphological similarity creates a challenge in identifying the species in the field, therefore, this study proposes a probe-based qPCR assay that uses single nucleotide polymorphisms (SNPs) that are fixed different between scalloped and Carolina hammerhead sharks, to rapidly identify them in the lab. Once designed, the assay will not only be able to identify scalloped and Carolina hammerheads, but also F1 hybrids. This molecular tool will enable further species-specific research focused on aspects of life history and ecology that are important for conservation and management. 

Keyword: conservation genetics 

 

Characterizing benthic invertebrate communities on eroding Texas Beaches 

Lily Tubbs(1*), Melanie Ponce(1), Terry Palmer(1), Kim Withers(2), Jennifer Beseres Pollack(1) 

(1)Department of Physical and Environmental Sciences, College of Science, Texas A&M University – Corpus Christi; (2)Department of Life Sciences, College of Science, Texas A&M University – Corpus Christi 

          Beaches along barrier islands of the Texas coast provide important ecological and socioeconomic benefits, however rapid shoreline erosion threatens the productivity of these coastal environments. Alterations to coastal geomorphology, due to climatic and anthropogenic stressors, stems from the inability of beaches to replace sediment simultaneous to the rate of erosion. Restoration techniques, such as beach nourishment, are utilized to temporarily mitigate the dissipating sediment, which provides vital habitat for benthic invertebrate communities and foraging grounds for shorebirds. Methods to understand the recovery rates of beaches after nourishment events include monitoring of important bioindicators such as benthic invertebrates. Bi-monthly monitoring of eight Texas beaches began in February 2023, with two beaches (Sargent and Jamaica Beach) set to be nourished in 2024. Sediment cores were collected in the swash zone to determine benthic invertebrate community composition. Spatial and temporal variability was examined for the most common fauna, amphipods of the family Haustoriidae and the spionid polychaete, Scolelepsis sp. Preliminary results indicate that these benthic invertebrates experience seasonal variations that could affect population dynamics. Temporal fluctuations in the benthic invertebrate community could directly affect shorebird usage and could potentially indicate an ideal period to perform nourishment events with the goal of minimal losses for larval recruitment. Establishing a timeline of overall beach recovery post-nourishment will aid in future beach nourishment plans targeted for Texas beaches. 

Keywords: restoration, coastline, intertidal zone, macrofauna, Galveston 

 

An image analysis technique to improve understanding of sedimentation effects on seagrass-epiphyte interactions 

Collin Kerr(1*), Kirk Cammarata(1)

(1)Department of Physical and Environmental Sciences, College of Science, Texas A&M University – Corpus Christi 

          Seagrasses globally face alarming rates of decline due to light attenuation by turbidity. Seagrass leaves are encrusted with complex biofilms primarily composed of algae known as epiphytes, and their interactions with the host plant remain poorly understood. However, their sensitivity to environmental factors such as light, nutrients, and dissolved gases makes them valuable bioindicators, similar to seagrasses themselves. This project aims to develop an improved image analysis method to describe epiphyte colonization on seagrass leaves, including aspects like quantity, morphology, and composition. The context for this work will be a study of the impacts of suspended sediment plumes on seagrasses. I predict that suspended sediments will reduce light and alter the characteristics of epiphyte biofilms and impact seagrass bioindicators negatively. Halodule wrightii shoots were gathered from a site with three distinct sedimentation disturbance levels: track one with no disturbance, track two with low disturbance, and track three subjected to high sedimentation disturbance. These seagrass leaves were arranged by shoot on a fluid mount tray for optical scanning after which epiphytes were removed by scraping and dried for biomass measurements. ENVI spatial image processing software (NV5 Geospatial) was used to remove the background from scanned leaf images (RGB), creation of RGB color band ratios, application of thresholds to differentiate epiphytes from seagrass leaves, and the quantification of identified image classes through pixel counting, yielding the total percentage coverage of epiphytes on the seagrass. The technique is promising, but further refinement and accuracy validation are required. This imaging approach has potential to enhance our comprehension of how sedimentation influences the accumulation of epiphytes and seagrass response. 

Keywords: remote sensing, OBIA (object-based image analysis), epibionts, estuarine, environment 

 

The effects of the pandemic and community management on the abundance of Hawaiian limpets 

Mare Rich(1*), Christopher E. Bird(1)

(1)Department of Life Sciences, College of Science, Texas A&M University-Corpus Christi 

          Hawaiian limpets (Cellana exarata) are an important staple of cuisine and culture across Hawai‘i. The primary threat to limpet populations is predation by humans. Thus, they are expected to be affected by “the tragedy of the commons” – wherein a public resource is overutilized by those acting in their own self-interest without an authority to enforce rules governing resource utilization. To combat the overharvesting of Hawaiian limpets, two community organizations established community-managed areas (CMA) in 2014 where the harvesting of limpets was discouraged, but there was no enforcement. Surveys (2014-2017) documented a significant increase in limpet abundance both inside of the CMA and up to 1km down current. Here we test for the effect of CMA on the abundance of limpets before and after the 2020 COVID-19 Pandemic. Transect surveys of limpet size and abundance were conducted in two CMA and two unmanaged areas in 2019 and 2022. A zero-inflated negative binomial general linear mixed model analysis was conducted in R using glmmTMB. The analysis tested for the effects of size (sublegal, legal), survey year, and the management regime on abundance. The population of legal-sized limpets was larger in the CMA than the unmanaged areas. Within management regimes, however, the number of legal-sized limpets remained consistent between 2019 and 2022, suggesting that the pandemic had no significant effect on harvesting pressure. The abundance of sublegal limpets fluctuated both between years and management regimes, but due to the stochastic nature of limpet larval recruitment, there is not enough evidence to suggest that the changes were related to the tested factors. These results demonstrate that even during a pandemic when people lost their jobs and needed an affordable source of food and additional income, contrary to the tragedy of the commons, compliance engendered by CMA without enforcement was sustained. 

Keyword: opihi 

 

River discharge effects on chlorophyll concentration variability in the northwestern Gulf of Mexico 

Adewumi Andrew(1*), Xinping Hu(1), Lei Jin(2) 

(1)Department of Physical & Environmental Sciences, College of Science, Texas A&M University-Corpus Christi; (2)Department of Mathematics & Statistics, College of Science, Texas A&M University-Corpus Christi 

          River discharge possesses the ability to influence biomass availability in aquatic systems, thus leading to effects in marine chlorophyll concentrations. Furthermore, variability in climate change patterns may negatively enhance these effects altogether. We analyze these trends over a 17-year period in the Gulf of Mexico within select banks within the Flower Garden Banks National Marine Sanctuary (FGBNMS). Through statistical analysis and time-series analysis, we anticipate correlation with fluctuations in river discharge significantly influencing chlorophyll concentration, with pronounced seasonal and interannual variations. Furthermore, we suppose delayed response with chlorophyll concentration echoes to river discharge in accordance with seasonal cyclical variability within the Gulf of Mexico. The significance of this study lies in its ability to assess the long-term implications of rising river discharge concentrations, potentially leading to harmful phytoplankton blooms that can have adverse effects on the Gulf's marine ecosystem. 

Keywords: eutrophication, nutrient enrichment, coastal ecosystem, environmental impacts, water quality fluctuations 

 

Organic matter content around and within an oyster reef 

Kalie Tovar(1*), Kelley Savage(1), and Jennifer Beseres Pollack(1) 

(1)Harte Research Institute for Gulf of Mexico Studies, Department of Physical and Environmental Studies, College of Science, Texas A&M University-Corpus Christi

          Oyster reefs provide numerous ecosystem services, including water filtration, shoreline protection, and habitat provisions for a variety of species. Another ecosystem service oysters may provide is carbon sequestration. Overall, the role of oyster reefs in the carbon cycle is understudied; however, oysters are known to act as both a sink and a source of carbon. Oysters act as a carbon sink by filter feeding and trapping suspended organic matter throughout the intricate reef structure. In contrast, oysters act as a carbon source through the formation of calcium carbonate shells, which produce carbon dioxide (CO2) that escapes into the atmosphere. Only eleven studies have quantified and reported carbon storage rates for oysters, and of those studies, the complex mechanisms affecting oyster reef carbon cycling are not always considered. Therefore, to account for these complexities, this research will evaluate sediment organic matter content around and within a restored subtidal oyster reef in St. Charles Bay, TX. Understanding the sediment organic matter around and within an oyster reef will help determine the areal extent to which carbon accumulates and if subtidal oyster reefs in St. Charles Bay, TX can impact the carbon found within the system. Sediment organic matter content results will be compared to elemental compositions of organic carbon to provide complementary information on carbon burial and potentially act as a proxy for carbon sequestration around and within a restored subtidal oyster reef. 

Keywords: blue carbon, Crassostrea virgincia, restoration 

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