Poster session: The Oyster is Your World

Oyster drills (Stramonita sp.) are marine gastropods that prey upon oysters in the northern Gulf of Mexico. Drill predation is largely considered to be salinity dependent; however, mean annual salinity varies across different states along the Gulf, especially between Texas, Louisiana, and Alabama. Previous experiments have shown behavioral differences between snails from those localities when exposed to various salinity levels (7-10 ppt). 


As morphological characteristics are an unreliable method of identification for this species, we analyzed the CO1 gene of the snails to examine the genetic makeup of the Stramonita species complex in the Gulf of Mexico. Analyzing the genetic structure will help us understand the discrepancy between different species within the Stramonita species complex versus local adaptation between the three localities.

Micro- and Nano-plastics (MNPs) are microscopic, plastic particles (5 mm- < 1 µm) that can be manufactured intentionally or derived from the breakdown of larger plastic waste through mechanical, physical, or biological processes. Due to their slow degradation rate, plastic waste can accumulate in aquatic ecosystems and increase the risk of uptake by marine animals in these environments. Some marine organisms particularly vulnerable to MNP ingestion are eastern oysters (Crassostrea virginica), found predominantly in the Gulf of Mexico. As discriminant suspension feeders, these oysters filter particles from water, retaining those suitable for digestion while expelling larger ones as pseudofeces. Despite this risk, their ability to recognize and dispose of ingested MNPs remains loosely understood. This study measured the presence of MNPs in the feces and pseudofeces of eastern oysters and compared concentrations and plastic types to those in their surrounding environment. Oyster samples were collected and examined from various reefs across the Mississippi Sound. Fluorescent staining using 4-Dimethylamino-4'-nitrostilbene (DANS) combined with epifluorescence microscopy was applied to identify and characterize different MNPs found in the oysters and water samples. Results revealed four major types of MNP particles in all samples-with a positive correlation between MNPs in the oyster byproducts and those in the surrounding water. Understanding the ecological pathways of microplastics, and their potential impact on oyster fisheries is important to understand the effects of plastic pollution on human and ecosystem health. This research provides valuable insights into the potential distribution of micro- and nano-plastics in coastal ecosystems.

Short, narrative-style climate scenarios are used to communicate plausible ecological futures in an accessible way to stakeholders from a wide range of educational and cultural backgrounds. Scenarios are generated using environmental models such as the Large Ensemble Community Project and focus on different environmental factors and how they may change over time. Models for this project focused on processes key for eastern oyster (Crassostrea virginica) survival, a species sensitive to climate change impacts. Factors include net primary productivity, pH, salinity regimes, and temperature in the Mississippi Sound and Mobile Bay over the next three decades. Results predicted higher salinities and water temperature and lower net primary productivity and pH, indicating stressful conditions for oysters. Climate scenarios depicting these conditions using scientific illustrations were distributed to oyster farmers and oyster harvesters from Alabama and Mississippi to communicate future impacts. Scenarios were accompanied by a 10-question survey to gauge what resources and techniques participants have to respond to environmental change, as well as how these possible responses can or will change with expanding climate impacts. Results can help identify the accessibility of known strategies and uncover novel strategies, which in turn could inform future policy and management strategies.

The Marine Science Program at Saint Stanislaus College (SSC) has been oyster gardening for the state of Mississippi since 2017. Each year, the SSC Marine Science Program receives hundreds of oyster shells covered in spat, that must be maintained free of sediment, algae and predators. In addition, oyster growth and salinity are also regularly measured and recorded. At the end of the growing season, the matured oysters are turned over to the Mississippi Department of Marine Resources (MDMR), to help restore oyster populations in Mississippi waters. Since 2017, the SSC Marine Science Program has grown just under 40,000 oysters for the state of Mississippi for restoration purposes. During this time, students in the SSC Marine Science Program have seen first hand how oysters, and the structures that they create, provide critical habitat for other marine species. Soon after the oyster gardens are deployed under our school pier, various marine life begins to grow. Encrusting organisms such as barnacles, mussels, and bryozoans are some of the first to appear. Followed by amphipods, blennies, gobies, skilletfish and various crabs. Depending on water quality conditions, some years tunicates, sea anemones and flatworms also become abundant. Over time, the oyster garden creates habitat for juvenile fish such as spadefish, mangrove snapper, sheepshead and pinfish in addition to crustaceans such as river shrimp, grass shrimp, snapping shrimp, and even new oyster spat. During high salinity growing seasons, the original oyster shells covered in spat become completely unrecognizable as they grow exponentially into natural clusters. It is these oyster clusters that create such vital habitat to all the other organisms mentioned above. This is why oyster gardening is critical to the Mississippi sound - to not only repopulate the depleted numbers of naturally grown oysters in our water, but to allow other species to thrive as well.

An estimated 51 coastal Mississippi restaurants sell approximately 4.8-5.2 million half-shell oysters per year, yielding 1.6-1.7 million pounds or 1,207-1,290 cubic yards of shell per year. On average, if a MS Oyster Shell Recycling Program (MS-OSRP) partnered with 20-40 restaurants, there could be a collection between 456-912 cubic yards of oyster shells over a one-year span. Repurposed shells can be used to support restoration efforts such as cultch planning, aquaculture, and shell for spat. Oyster reefs have been shown to provide a variety of ecosystem and economic services such as nitrogen removal, habitat for marine species, and commercial harvest. Recycling oyster shells from restaurants can help benefit oyster resources and connect restaurant patron to participate in that effort.


Oyster shell recycling is not a new concept, but recycling used oyster shells from restaurants in Mississippi has not been adopted. There are established programs in the United States that have successfully collected used oyster shells from restaurants that would otherwise be discarded into the landfills. The "Save Our Shells" program was created as a pilot program to document the viability of establishing a shell recycling program in Mississippi. 


On the poster, I will discuss the cost and benefits of having an oyster shell recycling program. I will address restaurant participation, quantify the amount of oyster shells to be collected, and the potential environmental and economic impacts that recycling oyster shells can have in Mississippi. 

Gunter Library collects and maintains archival materials related to the history of the Gulf Coast Research Laboratory (GCRL), its faculty, staff, students, and programs. Significant among these materials are publications, newspaper clippings, reports, and photographs generated by and about the research done at GCRL. As part of an ongoing effort to document and preserve the history of the GCRL, this project focused on work done at GCRL about oysters and the oyster industry. For more than a century, oysters have comprised a significant state economic resource. GCRL research has been the foundation for Mississippi Department of Marine Resources and its predecessors when developing oyster resources management plans. Environmental impacts including the openings of the Bonnet Carre Spillway, the Deep-Water Horizon oil spill, and climate change have all influenced the oyster populations and oyster reef health. Articles, reprints, newspaper clippings, and other historical materials were sorted and organized for preservation and conservation purposes. Publications were added to Gunter Library's GCRL publications database and copies of printed publications were digitized.

Climate change and extreme weather events are expected to directly impact various aspects of the economy including the oyster farming industry along coastal regions, including the Southeast US and the island of Ireland. Some impacts include increased frequencies in weather-related and disease-related closures preventing oyster harvest. As a result, it is vital to know what the variety of impacts of climate change and extreme weather may be on the industry, farmers' knowledge of these impacts, and ways to become more resilient to these future changes. The project aims to examine oyster farming community members' perceptions of climate change and extreme weather events and the impacts on the industry, using a survey which consisted of Likert-scale and open-response questions. Following the survey, semi-structured Zoom interviews were conducted to further examine what oyster farmers perceive as the most significant impacts of extreme weather events. A unique aspect of this project is comparing the similarities and differences between the perceptions of Southeast US and Irish farmers. This study provides valuable insights to the climate perceptions of oyster farmers which can help support future efforts aimed to improve climate resilience in the industry.

Analyzing the gaping behavior of oysters is essential for assessing their health, behavior, and interactions with the environment. This study enhances current techniques to create a fully automated system for real-time measurement of oyster gape. The goal is to provide valuable insights into various physiological conditions, including spawning, feeding, and aging. Our methodology employs the HAL 2425 Hall Effect sensor with a small magnet and an ESP32 microprocessor to accurately gauge the distance between the sensor and the magnet attached to the oyster shells. The system is engineered to collect sensor data at a rate of 10 Hz and transmit it via Wi-Fi at 1 Hz to a cloud-based storage solution on AWS, facilitating remote data analysis and monitoring. To guarantee the precision of distance measurements, each sensor is subjected to a linearization process before deployment. The analog-to-digital converter (ADC) values obtained are transformed into accurate distance measurements that directly reflect the gape of the oyster. This data is crucial as it generates a continuous dataset that can be analyzed to forecast essential behaviors, including spawning events, feeding patterns, and various environmental responses. The oysters utilized in this research are sourced from the Mississippi Gulf region and supplied by the Gulf Coast Research Laboratory (GCRL). They are kept in laboratory tanks under controlled environmental conditions optimized for growth and behavioral observation, where the gaping measurement setup is maintained.
Our efforts go beyond conventional laboratory analysis by incorporating cloud computing technologies for data storage and processing. Utilizing AWS enables remote access and data analysis, minimizing the necessity for continuous physical presence in the laboratory. The gathered time-series data is converted into the frequency domain through the Fast Fourier Transform (FFT) algorithm, with spectral analysis uncovering notable spikes in power within the 0.3 Hz to 1.3 Hz range, which indicates spawning activity. Initial findings suggest that applying a threshold of 0.1 dB within this frequency range facilitates precise predictions of spawning events.
This research introduces an innovative and scalable approach for measuring oyster gape in real-time, applicable to aquaculture management, ecological monitoring, and marine biology research. Combining cutting-edge sensor technology, microcontroller programming, and cloud computing establishes a strong foundation for ongoing and remote tracking of oyster behavior, paving the way for more advanced investigations in bivalve biology.

Expansion of aquaculture is needed to meet the increasing demand for seafood products due to a growing world population. Shellfish aquaculture plays a crucial role in aquaculture production, with the Eastern oyster, Crassostrea virginica, being one of the most important species in the United States. Seed supply is a limitation to the expansion of the oyster aquaculture industry in the Gulf of Mexico (GoM), and hatcheries report incidences of high mortality. Methods are needed to reduce mortalities and improve the consistency of oyster larval production to increase hatchery production for the GoM. Probiotics, which are beneficial bacteria, have demonstrated effectiveness in improving the growth and survival of various marine species. Thus, the purpose of this study was to determine the effects of probiotics on Eastern oyster larval rearing. 


Mixed Bacillus probiotics proven to increase survival and stress resistance in marine fish larvae were supplemented once daily at 7.0x105 CFU/mL to triplicate static, small-scale oyster larval rearing systems. An additional three systems served as controls that did not receive the probiotics. Survival, growth, and number of eyed larvae, along with water quality parameters, were monitored in each of three separate 18-day trials. Water changes occurred every other day until eyed larvae began to develop, at which point, water was changed daily. Larvae were batch-fed algae concentrate twice per day based on larval size and density. The eyed larvae collected throughout each trial were subjected to high throughput sequencing for characterization of their associated bacterial communities (microbiota). We hypothesize that the presence of probiotics will significantly improve the growth, survival, and setting rates of oyster larvae through the early establishment and development of the larval microbiota.