ContactSite MapSearchNews
Inside Sea GrantResearchExtensionEducationFundingProductsEvents

SC Sea Grant Consortium
287 Meeting Street
Charleston, SC 29401
p: 843.953.2078
f: 843.953.2080
FY12-13 Impacts and Accomplishments – RESEARCH
Impacts and Accomplishments – RESEARCH 


FOCUS AREA:  Sustainable Fisheries and Aquaculture
GOAL(S): A healthy domestic seafood industry that harvests, produces, processes, and markets seafood responsibly and efficiently.
PARTNERS: Swimming Rock Fish and Shrimp Farm, Ladys Island Oyster Farm, Inc.
TITLE: Development of a Sustainable, Minimal-Water Exchange, Polyculture Biofloc-Based, Mariculture Production System
PI: Leffler, S.C. Department of Natural Resources

RELEVANCE: A robust aquaculture industry is needed nationwide to meet rising demands for safe and healthy seafood, while minimizing its impacts on the natural environment. A national workshop sponsored by NOAA and NIST was convened in 2008 to evaluate how the United States could overcome technical barriers to competitive marine aquaculture. The conference concluded that to become economically competitive and environmentally responsible in mariculture, the United States would have to rely upon innovative technology as its major strength.

RESPONSE:  Sea Grant researchers are examining a minimal-exchange biofloc technology-based system, for use in the development of a functional, environmentally friendly, economically competitive, indoor polyculture system for raising high value crops of fish, shrimp, and oysters in the U.S. Three complete recirculating polyculture systems have been developed in year 1, two of which have been tested using combinations of shrimp, oyster, and red drum stock.
RESULTS: The first system supported all three organisms. Results demonstrated that shrimp and red drum had high survival rates (90% and 100%, respectively), while the oyster survival rate was less than 25%. In the second system, only shrimp and red drum were stocked, with slightly lower survival rates. The researchers have determined that the food management process must be altered to allow for better observation of feeding behavior, which they are now addressing in year 2 of the study.

RECAP: Sea Grant-supported research into recirculating polyculture systems has the potential to allow aquaculture producers to meet rising demands for seafood while minimizing their impact on the natural environment.

FOCUS AREA: Sustainable Fisheries and Aquaculture
Title: Modeling Drought and the Decline of Blue Crabs in South Carolina
PI: Childress, Clemson University
Project Number: R/CF-15
Partners: NIDIS, SCDNR State Climatology Office

RELEVANCE: Coastal wetland habitats are undergoing a dramatic shift in environmental conditions due to coastal development, water management practices and global climate change. Many salt marshes have experienced large-scale diebacks linked to increasing drought conditions, although the causative mechanisms are still being debated. Since salt marsh habitats are important nurseries for many commercial species, including finfishes, shrimps, and blue crabs, it is important to understand the influence of drought on salt marsh and fisheries health.

RESPONSE: In an ongoing effort to determine why blue crab landings decline with increasing salinity, Sea Grant researchers at Clemson University undertook quarterly censuses of blue crabs at 27 stations in the ACE Basin NERR, and conducted an additional experiment to estimate crab growth, survival, and postlarval settlement. This was included in the work completed on a blue crab forecasting model (SCBCRABS) for the ACE Basin NERR. 

RESULTS: This spatially-explicit individual-based model of blue crabs uses historical or projected river discharge (flow) estimates to reproduce the spatial, seasonal and annual variation in salinity. Both laboratory and field data on the impacts of salinity on crab settlement, growth, movement, disease transmission, predation, fishing effort, and natural mortality have been incorporated. The model is ready for use by fisheries managers that wish to forecast blue crab populations under various scenarios involving changes in freshwater flow, fishing effort, or both.

RECAP: The model predicts that crab abundance peaks at intermediate flow rates but then declines rapidly with further reductions of freshwater flow, and that increasing disease is the most important driver linking salinity to crab density. 

FOCUS AREA:  Sustainable Fisheries and Aquaculture
Title: Development of Population Genetic Tools for Blue Crab Management
PI: Darden, S.C. Department of Natural Resources
Project Number: P/M-2L & 2T
Partners: n/a

RELEVANCE:  The Atlantic blue crab (Callinectes sapidus), supports valuable commercial and recreational fisheries.  Both commercial and fishery-independent landings have shown a steady decline in blue crab abundance over the past decade, making C. sapidus a potential species of concern for fisheries managers. However, our understanding of blue crab biology is lacking is several areas, including offshore population composition (i.e. reproductive or senescent females), overwintering behavior, reproductive output of estuaries, recruitment bottlenecks and habitat limitations, and settlement cues.

RESPONSE: Sea Grant researchers are developing techniques to support the development of a responsible stock enhancement research program for blue crab that will focus on the use of cultured animals to address these fundamental population ecology questions; information generated will in turn be valuable for improving management decision-making.  Investigators completed the initial steps in development of a population genetics tool to serve as the foundation of a blue crab research and stock enhancement program; optimization of four microsatellite markers for Callinectes sapidus were investigated as non-lethal tags to identify hatchery-raised individuals.

RESULTS: Microsatellite loci from 25 blue crab samples were obtained and evaluated. Preliminary evaluation suggests that these four loci will be valuable in both the genetic characterization of blue crab populations in South Carolina as well as their application as genetic tags for experimental stock enhancement research. 

RECAP: Once the final suite of loci is developed, these markers will serve as permanent, non-lethal tags for identifying hatchery-raised blue crabs during and after stock enhancement.  Results of blue crab stocking can then be used to provide valuable information on blue crab ecology and life history that can be incorporated into fisheries management decisions.

FOCUS AREA:  Hazard Resilience in Coastal Communities
GOAL(S): Sufficient community capacity to prepare for, adapt to, mitigate, and recover from hazardous events
PARTNERS: Olsen and Associates, Inc.
TITLE: Observational and Modeling Studies to Benefit the Management and Selection of Borrow Sites for Beach Nourishment in South Carolina
PI: Xu and Wren, Coastal Carolina University

RELEVANCE: Beaches are common sedimentary environments along the South Carolina coasts.  The condition and stability of these beaches form an integral part of South Carolina’s economy, primarily by providing support for local tourism and infrastructure protection during storm events. South Carolina has adopted beach nourishment as the predominant strategy for addressing adverse effects of coastal erosion. Since 1985, at least 24 nourishment projects have occurred in South Carolina, with a total of over 27.5 million cubic yards of sand added at a price of nearly $225 million. Coastal sand resources in South Carolina suitable for beach nourishment are very limited. Efficient and low-impact use of those resources is important to the sustainability of future nourishment programs state-wide, as well as the management of sediment resources regionally.

RESPONSE:  Few studies have been done for reliably predicting borrow pit infill rates and sediment composition based on expected borrow area placement and design. Sea Grant researchers seek to provide this crucial information to a coastal community by employing, through this pilot effort, an intense sediment transport observation and modeling effort and partnering with a private consulting firm that provides technical help to the community on these issues.

RESULTS: Year 1 results include the collection of in-situ observations of hydrodynamics and suspended sediment transport and related data for model input.  Several sediment transport models have been run and are being validated, and meteorological and oceanographic data have been compiled and pre-processed for inclusion in the Regional Ocean Modeling System (ROMS) model, which continues to be developed.

RECAP: An understanding of how borrow pits, which are created as the result of dredging for beach nourishment, infill based on hydrodynamic and sediment transport data and subsequent Regional Ocean Modeling System ROMS) development will inform both resource management agencies and coastal communities state-wide about how borrow pits in various locations infill after sand dredging has been conducted.

FOCUS AREA:  Sustainable Coastal Development and Economy
GOAL(S): Healthy coastal economies that include working waterfronts, abundant recreation and tourism opportunities, and coastal access
PARTNERS: SC Department of Natural Resources
TITLE: Understanding demand for value-added products and services associated with for-hire boat trips on the South Carolina (SC) coast
PI: Brookover and Jodice, Clemson University

RELEVANCE: Recreational charter fishing boat operators on the SC coast provide access to offshore waters, but increasingly they must adapt to higher fuel costs, regulatory limitations, competition, and customers seeking lower prices. A promising strategy may be trips with new or expanded experiences such as interpretation of fish ecology, marine resource management, local history or even offshore energy development. We know that SC coastal tourists are interested in guided nature and historical tours, but not whether anglers and/or non-anglers would be more attracted to offshore trips with these experiences. We do not know how much charter operators are including these experiences or their preparation for delivery of information on these topics that is credible, timely, interesting and engaging for customers.

RESPONSE:  In year 1, Sea Grant researchers interviewed charter captains with a SC charter license during the summer of 2012. Captains were asked about the value-added services that 1) they are currently or considering providing, and 2) are in demand by anglers and non-anglers. They were asked to define the strengths, opportunities, weaknesses and threats to providing value-added products and services. They also completed a self-assessment survey regarding importance of (to consumers) and preparation for competencies related to knowledge of fishing, marine ecology and history, and interpretive skills.

RESULTS: Some charter captains were providing trips to non-anglers and were flexible to different consumer interests. Some were reluctant to add services with time or financial costs. Threats to adding value included the poor networking relationship with the tourism community and among charter captains. Captains desired training in marketing and customer service.  Several were interested in training on the local history and marine environment. However, most self-assessed their preparation in various competencies (e.g., knowledge about marine ecology) as equal to, or better than, importance to the consumer. Consequently, identifying actual training needs in natural history knowledge and interpretation may require expert evaluation through ride-alongs on charter trips. Respondents also self-assessed their interpretive skills as high, but gave the lowest rating to their skills in using multiple styles of communication and tailoring messages to different types of user groups. While they considered adding value to be a viable strategy, they suggested that training in marketing and customer service was  important.  

FOCUS AREA:  Sustainable Fisheries and Aquaculture
GOAL(S): A sustainable supply of seafood that meets public demand at competitive prices.
PARTNERS: North Carolina Sea Grant
TITLE: Managing Reproductive Behavior in Fisheries and on Fish Farms
PI: Chapman et al., S.C. Department of Natural Resources
Project Number: R/CF-19

RELEVANCE: Persistently poor egg quality is a major problem in finfish aquaculture and has remained intractable and of unknown cause(s) despite decades of attention by researchers around the world. Recent research has strongly implicated dysfunction of ovarian gene expression as a root cause of the problem. Researchers hope to discover patterns of ovarian gene expression associated with high and low egg quality in striped bass which will identify the specific physiological functions that are impaired and point the way toward changes in husbandry practices that can optimize egg quality. In addition, they will extend the analysis to wild caught individuals and evaluate the capacity of gene expression profiling as a tool for assessing the egg quality.

RESPONSE:  During the spring of 2012, researchers induced both domesticated and wild striped bass from the Roanoke River in N.C. to complete maturation and ovulation for hatchery evaluations of egg quality (fertility, embryo and larval development, etc.).  The fish were subjected to ovarian biopsy prior to the experiment and a sample of their eggs was collected at spawning and subsequently preserved. In fall 2012, researchers collected biopsies from the vetted samples from the spring spawning activity to assess the subsequent development and maturation as required by the grant objectives.

RESULTS: Patterns of gene expression are being identified in order to detect "fingerprints" of gene expression genes that can predict egg quality and potential reproductive fitness of wild and farmed striped bass.

RECAP: The research is expected to result in a gene expression profiling tool to enhance the efficient production of hybrids for grow-out facilities and to inform fisheries management policies.

FOCUS AREA:  Sustainable Fisheries and Aquaculture
GOAL(S): A sustainable supply of seafood that meets public demand at competitive prices
PARTNERS: Spyglass Technologies; MBARI; Oligos, Etc.
TITLE: Development of a Novel Genetic Approach to Rapidly Detect and Quantify Fish Eggs of Commercially Important Species: A New Tool for Fisheries Management
PI: Greenfield and Arnott, S.C. Department of Natural Resources

RELEVANCE: Indices of fish egg production are essential for understanding recruitment and developing stock assessment models for species management. Traditional methods of enumerating and identifying planktonic fish eggs entail time-consuming microscopy. Furthermore, eggs of different species are often morphologically indistinguishable, leading to erroneous population assessments that affect management decisions.

RESPONSE:  Sea Grant researchers are addressing this problem by developing a rapid, cost-efficient, and novel molecular tool that will facilitate fish egg identification and quantification using the economically important species red drum (Sciaenops ocellatus) as the target organism. During the effort to design the species-specific egg identification tool, specific rRNA regions of interest from the target species and several closely related species were compared.

RESULTS: It was discovered that there was little interspecific genetic difference between the fish, so a species-specific capture probe could not be developed from that particular rRNA region. To overcome this, a more versatile genome was sequenced, and this revealed several regions that were distinct and therefore promising candidates for probe design. Additionally, researchers designed both new capture and signal probes for the sequenced genome region. Efforts have led to initial discussions with an industry partner to make the probes available upon completion of the research.

RECAP: South Carolina Sea Grant sponsored research is leading to the development of new genetic probes useful in rapid, species-specific identification and quantification of commercially-important fish species.

FOCUS AREA:  The Coastal and Ocean Landscape
GOAL(S): Widespread use of ecosystem-based approaches to managing land, water, and living resources in coastal areas.
PARTNERS: Horry County Stormwater Management Program, Coastal Carolina University, Robinson Design Engineers, Carolina Clear, Horry County Public School District
TITLE: Green Infrastructure Design for Stormwater Management in Coastal South Carolina: An Assessment of Ecohydrological Function
PI: Jayakaran, Clemson University

RELEVANCE: A better understanding of hydrological and ecological mechanisms to achieve design targets for stormwater volume and flow reduction, including soil and vegetation characteristics, is necessary for coastal areas. The scientific literature for hydrodynamic and pollutant removal efficiencies using bioretention systems is extremely varied due to diversity in system design and also variability in rainfall distribution patterns and existing site conditions for respective drainage areas. Minimal information exists about the hydrologic function and performance of vegetative systems in landscapes with shallow water tables where surface and groundwater interactions are prevalent. Research is needed to examine the efficiency and effectiveness of these stormwater practices in water quantity reduction and water quality improvement in the managed landscape. Specific investigations into the role of these practices are necessary for providing effective design criteria and maintenance practice recommendations for coastal communities that do and will use these practices for managing stormwater quantity and quality.

RESPONSE:  Five sites that reflect green infrastructure design practices in coastal SC are currently being assessed for ecohydrological function. All five locations have been instrumented with soil moisture sensors to three depths, a ponding surface level well (where appropriate) and deep water table well, and inflow and outflow sampling devices, rain gages, and lastly groundwater sampling ports at 3 depths below ground surface.  Soil cores were extracted from each of the bioretention cells to a depth of approximately 10ft and analyzed for particle size distribution and organic content. At each of the five locations, surface and subsurface response to rainfall events are being characterized using soil moisture sensors and water table level logging transducers to capture this information at a high temporal frequency. Monitoring has been conducted since July 2012. To date, an average of 9.6 storms have been sampled across all five bioretention sites, with sampling efforts scheduled to continue until October 2013.

RESULTS: A spreadsheet-based technique to filter out signal noise from soil moisture sensor data has been developed. Researchers are in process of developing an automated and more functional approach using statistical and computational software to process data.  In addition, they are working to modify an existing water budget tool using STELLA simulation software for bioretention cells that exist in locations where shallow water tables persist.

RECAP:  The science-based tools under development by Sea Grant researchers will allow state stormwater managers to meet requirements resulting from anticipated changes to the NPDES Phase II permit requirements both nationwide and within South Carolina.

FOCUS AREA: Sustainable Fisheries and Aquaculture
Goal(s): A healthy domestic seafood industry that harvests, produces, processes, and markets seafood responsibly and efficiently.
Title: Biomedical Industry Cooperation with Sea Grant Researchers Confirms Efficacy of Current Management Strategies for the Commercial Horseshoe Crab Fishery
PI: DeLancey, S.C. Department of Natural Resources
Project Number: R/CF-14
Partners: ASFMC, South Carolina Aquarium, Endosafe

RELEVANCE: Due to increasing numbers of horseshoe crabs being bled annually by the biomedical industry on the U.S. east coast, an Ad Hoc Biomedical Workgroup was convened by the Atlantic States Marine Fisheries Commission (ASMFC), the entity in charge of coastwide management of horseshoe crabs through the member states. Results demonstrating no appreciable difference between rates of live return for bled and unbled horseshoe crabs were reported to both the Workgroup, which is documenting best management practices in the bleeding industry, and ASMFC Horseshoe Crab Technical Committee. An appreciable number of short-term bleeding effect studies have been conducted on horseshoe crabs, but few published long-term studies exist, which would aid in better assessing potential impacts on the population in South Carolina. 

RESPONSE: A biomedical company (Endosafe) allowed Sea Grant researchers to tag horseshoe crabs at their facility, and provided bled crabs gratis as part of a long-term study to document potential differences in tag return rates (survival) between bled and unbled horseshoe crabs. Endosafe recorded all tagged animals brought to the facility by harvesters, and provided SCDNR with data in a timely manner. Endosafe also agreed to not bleed any of the tagged animals, thus harvesters returned them to the wild along with routinely bled animals. 

RESULTS: Study results suggest that there are no long-lasting impacts on the horseshoe crabs due to biomedical bleeding; therefore, the hosreshoe crab fishery continues to operate without the need for significant management changes. Through its cooperation in this study, the biomedical company Endosafe contributed valuable information to the long-term management goal of a sustainable fishery for horseshoe crabs.

RECAP: These short-term studies enabled an evaluation of current practices and possible future management policies for horseshoe crabs. In addition, communication and collaboration among the harvesters, biomedical industry, and fisheries managers have improved substantially, benefiting all concerned.

:  Hazard Resiliency in Coastal Communities
Goal(s): Sufficient community capacity to prepare for, adapt to, mitigate, and recover from hazardous events.
Title: Sea Grant Researchers Develop a Wind-Borne Debris Trajectory Model to Assess Risk to Coastal Structures during Hurricanes
PI: Pang, Clemson University
Project Number: R/CH-2
Partners: Rensselaer Polytechnic, Princeton University, University of Auckland, University of Western Ontario, University of Florida, Institute for Business and Home Safety

RELEVANCE: Damage costs and losses due to hurricanes have increased dramatically over the years. This is partly attributed to continued population growth along coastal regions, which result in more high-value properties being exposed to extreme wind hazards. In South Carolina, the population of the coastal community is approximately one million and growing. Coastal communities of South Carolina, such as Myrtle Beach and Charleston, are especially vulnerable to the annual hurricane risk, as they are popular tourist destinations and significant economic drivers for the state. Indeed, South Carolina was ranked 6th in the nation with over 196,000 properties valued at nearly $66 billion deemed vulnerable to hurricane damage (CoreLogic, 2013). The majority of damage experienced by coastal residential structures during a hurricane is mainly attributed to damage to the building envelope, more specifically damage due to wind-borne debris impact. Emergency managers and response teams would benefit from a better understanding of the relationship between wind-borne debris and the ability to recover from a hurricane event.

RESPONSE: Sea Grant researchers performed a wind-borne debris study focusing on South Carolina coastal regions with a goal of predicting building envelope failures and damage probabilities of residential structures due to hurricane-borne debris impact.  Cladding systems, windows, and doors have traditionally been treated as non-structural components; therefore, structural engineers do not usually design building envelopes.  As a result, extensive damage to the cladding systems has been reported after almost every major hurricane. In recent years, many engineers and researchers have begun to recognize the importance of building envelope design.

RESULTS: A three-dimensional probabilistic debris trajectory model was developed to assess the debris impacts risk of coastal structures during the landfall of a hurricane.  This probabilistic debris flight model has been incorporated into a computer model which can be used to predict the building envelope failure risk of coastal communities.  Also, a novel method of assessing the probability of impact and damage (failure) of vulnerable components of the building envelope based on the orientation of individual homes within the subdivision has resulted in the development of a polar coordinate debris impact risk plot. Government officials, developers, architects, and designers will be able to utilize the full spectrum of probabilities as a pre-construction mitigation technique for individual homes or entire subdivisions, or post-construction to identify which vulnerable areas of the building envelope would benefit the most from protection in the event of limited resources to devote to mitigation.

RECAP: The debris trajectory model has the potential to help many stakeholders by interfacing with the South Carolina hurricane wind hazard model, which characterizes the hurricane wind hazard of coastal South Carolina regions, and will function to mitigate the hurricane risks in the area.

FOCUS AREA:  Sustainable Fisheries & Aquaculture
A healthy domestic seafood industry that harvests, produces, processes, and markets seafood responsibly and efficiently.
PARTNERS: Swimming Rock Fish and Shrimp Farm, Ladys Island Oyster Farm, Inc., Scientific Association, University of Arizona, Auburn University, Southern Drawl Outfitters
TITLE: Commercialization of Bait Shrimp Aquaculture through Year-Round Production using Indoor Clear-Water and Biofloc Culture Systems
PI: Leffler, S.C. Department of Natural Resources

RELEVANCE: There are over 8 million recreational saltwater anglers in the United States who contribute $30 billion to the nation’s economy; South Carolina ranks eighth in the nation in terms of number of resident anglers, and fifth in terms of non-resident anglers. Live bait shrimp account for approximately 30% of gross sales for bait dealers in the Southeast; consequently, supplying live bait to recreational fishermen is a significant coastal industry. 

RESPONSE: Building on recent hatchery projects, researchers attempted to develop and optimize protocols that would enable year-round husbandry and grow-out production of bait shrimp for the establishment of a culture-based commercial bait shrimp industry. 

RESULTS: The determination of optimal stocking densities for growth of Litopenaeus setiferus PL and juveniles was accomplished.  Researchers determined that the growth rate of L. setiferus is greater in biofloc systems than in clear-water systems, but that there is greater variability in the size of animals produced and more variability among replicate tanks. Researchers also monitored production costs and developed simple economic models for growout expenses versus sales prices. The economic analysis of bait shrimp production using the technologies evaluated was completed and shared with collaborators in Texas, Alabama, and Florida. The analysis suggests that, except in very unusual circumstances, production and marketing of bait shrimp in indoor, year-round facilities is not economically feasible. 

RECAP: The resultant cash flow economic model for small farmer, indoor, year-round bait shrimp growout demonstrates year-round bait shrimp husbandry and growout is not an economically viable enterprise at this time.

FOCUS AREA:  Sustainable Fisheries and Aquaculture
A sustainable supply of seafood that meets public demand at competitive prices
PARTNERS: VIMS, Island Fresh Seafood, 4Cs Breeding Technology, SCDHEC
TITLE: Policy Implications from Comparative Research on the Survival and Growth of Diploid and Triploid Single Eastern Oysters in South Carolina
PI: Kingsley-Smith, S.C. Department of Natural Resources

RELEVANCE:  Populations of the Eastern oyster, Crassostrea virginica, have declined along much of the mid-Atlantic coast of the US during the last century due to factors such as over-harvesting and habitat degradation. Despite this, South Carolina estuaries continue to provide excellent growing conditions for native oysters. Considerable economic potential exists for the production of locally-derived single oysters raised from hatchery seed. Maximizing this economic potential requires the optimization of grow-out techniques and the evaluation of potential merits of the use of triploids compared to diploids.

RESPONSE:  The goal of this Sea Grant-funded project was to evaluate the performance of triploid Eastern oysters, which are thought to be advantageous in aquaculture due to their sterility, improved meat quality, and in many cases superior growth, as a candidate species for single oyster aquaculture in South Carolina.

RESULTS:  This project highlighted the need to re-visit the SCDNR policy which governs indigenous shellfish importation. Specifically, this recent research presented opportunities to consider scenarios not previously envisaged when the original policy document was written, at a time when importations were primarily associated with the movement of hard clam (Mercenaria spp.) seed and brood stock. Such variances from the original policy document included the use of polyploid animals, importations of eyed larvae and small seed (as opposed to the movement of brood stock animals), the efficacy of the hatchery certification process, advances in disease diagnostic techniques, discussions surrounding the need for an updated outlook on shellfish disease management at a regional scale, and the need to consider genetics as well as disease and hitch-hikers in terms of potential risks to South Carolina oyster populations from indigenous shellfish importations. A new demand for triploid oysters in South Carolina has resulted from this project. Two commercial shellfish growers involved in this project applied for applications to import their own triploid oysters for commercial grow-out in February 2013 and it is likely that in the future more commercial growers will want to import more triploid oysters due to their now proven high growth rates in South Carolina waters.

RECAP: Research on the survival and growth of diploid and triploid single Eastern Oysters in South Carolina is shedding new light on the state’s existing policies regarding indigenous shellfish importations.

FOCUS AREA:  The Coastal and Ocean Landscape
Widespread use of ecosystem-based approaches to managing land, water, and living resources in coastal areas
PARTNERS: North Inlet-Winyah Bay NERR
TITLE: Consequences of altered temperature regimes on the reproduction, survival, growth and interactions of two key estuarine fauna
PI: Harding and Allen, Coastal Carolina University and University of South Carolina

RELEVANCE:  Oyster reefs are among the most important estuarine habitats in South Carolina estuaries. However, long-term water temperature data from the North Inlet estuary indicate an increase in water temperatures of about 0.9°C from 1979-2010 and future increases are predicted to occur due to climate change. Increased temperatures may alter habitat use patterns, seasonal reproductive timing, and ecological interactions between and among species which inhabit oyster reefs. Oysters and gobies are representative of lower estuarine trophic levels, and changes in larval interactions between these keystone species could affect the population dynamics and persistence of oysters and recreationally-valuable finfish. Integrating information from more than 30 years of measurements and process-oriented experiments will provide new insights in the patterns, directions, rates, and mechanisms of changes to these populations and habitats due to changing environmental conditions.

RESPONSE:  Sea Grant researchers are defining the ecological effects of increased winter water temperatures on intertidal estuarine and tidal creek habitats using oysters and gobies as indicator species. The effects of increased water temperature on adult reproduction, larval biology, and larval oyster- larval goby interactions are being examined using a combination of field, culture, and experimental methods. 

RESULTS:  Baseline data collection through larval fish feeding experiments, descriptions of fish population demographics and spawning patterns, and plankton collection are nearly completed. Analyses of these data will allow for an evaluation of ecological effects of a variety of parameters on oysters and gobies.       

RECAP:  Predictive tools to interpret historical plankton data sets on species associated with estuarine oyster reefs are currently under development by Sea Grant researchers.

: Sustainable Fisheries and Aquaculture
A healthy domestic seafood industry that harvests, produces, processes, and markets seafood responsibly and efficiently.
Title: Novel Analytical Approaches Being Used to Develop Telomere-Based Aging Tools for Long-Lived Marine Fishes
PI: Darden, R/CF-16
Partners: MUSC, NOAA HML

RELEVANCE: Accurate monitoring of fish populations and proper management of fisheries is of utmost importance to fisheries managers as increased fishing pressure and human perturbation of habitats can cause fish populations to decline.  Evaluation of fish population health is generally provided by periodic model-based stock assessments, of which age structure is one critical population parameter. Management of many long-lived marine fishes lack critical age structure parameters for all or a portion of their life stages and, therefore, future assessments and management will substantially benefit from the inclusion of information generated from a non-lethal, telomere-based aging tool.

RESPONSE: In light of recent publications indicating the failure of telomere-based aging tools for natural populations, and the likely high noise that was driving these conclusions, Sea Grant researchers conducted several experiments to maximize noise reduction in the estimation of telomere length from red drum and cobia field samples.  They optimized protocols to overcome restriction digestion inhibition and to ensure repeatability of telomere length estimation. In addition, an evaluation of preservative and DNA isolation protocols was completed as they both result in some degree of DNA shearing and little is known about the influence of these factors on either the overall degree of impact or pattern of impact throughout the genome. 

RESULTS: The researchers’ comparison of telomere distribution among preservative/isolation protocols suggests similar distributions following isolation as well as after restriction digestion. No differences were observed in average telomere length based on preservative or isolation protocols, and these protocols were sampling approximately the same number of telomeres within each sample. Sea Grant researchers have made substantial progress in the development of the red drum standard curve for telomere-based aging. The resulting increased understanding of telomere loss patterns in natural populations has allowed researchers to test two novel analytical approaches for the development of telomere-based aging tools.

RECAP:  Though researchers were unsuccessful in developing a telomere-based non-lethal tool for estimating age in these recreational fishes, substantial improvements in telomere laboratory techniques and data analysis have allowed application of these methodologies to the endangered Atlantic sturgeon. Initial results indicate that telomere shortening mechanisms may differ between teleost and non-teleost fishes.

FOCUS AREA:  Sustainable Fisheries and Aquaculture
A healthy domestic seafood industry that harvests, produces, processes, and markets seafood responsibly and efficiently
PARTNERS: SC Seafood Alliance
TITLE: Examining Capacity for a Cooperative Seafood Tourism Trail as a Value-Added Marine Resource-Based Recreation and Tourism Product on the South Carolina Coast
PI: Brookover et al., Clemson University

RELEVANCE:  South Carolina offers unique experiences related to seafood harvest and production, maritime history and culture of fishing, marine fisheries ecology, and seafood culinary interests. South Carolina’s coastal tourists are supportive of sustainability initiatives for local marine-resource dependent businesses. A seafood-themed drive trail could be an incubator for entrepreneurship and create more opportunities for marketing local seafood products through a unified brand image. While other theme-based trails exist in the region, there has been no assessment of the potential for a South Carolina seafood trail and related capacity for this type of business incubator.

RESPONSE:  An advisory panel was formed that included Sea Grant Extension Specialists Amber Von Harten, April Turner, and Jack Whetstone, and South Carolina Seafood Alliance Director Frank Blum. A list of 114 potential interview participants was created through consultation with the advisory panel and the Market Maker and Certified SC Grown databases, as well as the list of restaurants on the SC Aquarium Sustainable Seafood Initiative website. The advisory panel assisted with prioritizing individuals for interview based on potential to contribute insight or leadership in the community.

RESULTS:  Researchers conducted interviews in the Mt. Pleasant, Charleston and Edisto region in December 2012.  Interviews were arranged by sending invitations to all individuals listed as high priority on the original invitation list and based on convenience (i.e., ability to schedule during the researcher's visit to the coast).  Researchers conducted 14 in-person interviews (7 seafood harvesters/wholesalers, 5 tourism businesses/organizations, and 2 seafood restaurant managers) during the initial visit. Researchers plan to conduct interviews in the Murrells Inlet McClellanville region during the first week in February, 2013 and in the Beaufort/Hilton Head Area in late February, 2013. Additional interviews will be conducted in Myrtle Beach and in Beaufort area in March 2013. 

RECAP:  South Carolina Sea Grant-sponsored research is evaluating the potential for a cooperative seafood tourism trail throughout coastal South Carolina.

FOCUS AREA:  Sustainable Coastal Development and Economy
Healthy coastal economies that include working waterfronts, abundant recreation and tourism opportunities, and coastal access
PARTNERS: Sea Island Coalition, Gullah/Geechee Angel Network
TITLE: Coastal Livelihoods and the Local Sense of Place: Assessing Social-Ecological Relationships and Environmental Values in the Face of Demographic Changes in Mount Pleasant, Awendaw, and McClellanville, South Carolina
PI: Watson, College of Charleston

RELEVANCE:  Recently released census data affirms that South Carolina is experiencing some of the highest rates of in-migration in the United States, and this in-migration is concentrated along the coast.  For example, the town of Mount Pleasant, now the fourth-largest in the state, saw a 42.5% increase in population just over the last decade. Many of these migrants come from cities across the country to enjoy the amenities of rural landscapes, especially the environmental amenities and the “sense of place” that comes from a coastal lifestyle. However, first understanding the relationships long-term residents have within their landscapes will allow those places and senses of place to be best protected. This becomes more urgent each year, as demands on the Lowcountry’s natural and economic resources increase.

RESPONSE:  Sea Grant researchers are assessing the social-ecological relationships of three South Carolina coastal communities in various stages of development. To do this they will examine (1) the ways that long-term residents economically relate to the environment, (2) the “sense of place” and the local environmental knowledge that is derived from this interaction, and (3) test the extent to which their environmental values coincide with that of the newer amenity migrants.

RESULTS:  Through the development of relationships with residents in the three communities, researchers were able to begin data collection and student training in fieldwork techniques. Key species of importance for varying constituencies were determined, and the primary coastal economies engaged in by long-term coastal residents were described. Measures that can be used by planners or managers were developed to assess the well-being of residents over time.

RECAP:  Sea Grant research to gain a deeper understanding of environmental beliefs and ecological relationships in three South Carolina communities will be relevant to natural resource managers and local governments in community planning efforts to account for population growth and the resultant impacts to the natural environment.

FOCUS AREA: Sustainable Fisheries and Aquaculture
Title: Novel Genetic Sequencing Pipeline Streamlines Efforts
PI: Anderson, College of Charleston
Project Number: P/M-2I

RELEVANCE:  The development of Next Generation Sequencing (NGS) has presented biologists with a vast new potential to examine the entire genome of non-model organisms with the goal of understanding adaptation and evolution of organisms. These tools are currently being applied to address such issues as reproductive failure in striped bass and will soon be replacing microarrays as the standard method of gene expression profiling. In addition, these data can be used to develop single nucleotide polymorphism panels, which are becoming the next generation of tools for studies in population genetics and evolution.

RESPONSE:  While the potential to interrogate the genome in such depth and in non-model species for which little or no genomics information is available, the massive amounts of data and the short read lengths create problems for individual investigators, including basic storage and transfer of large quantities of data. 

RESULTS:  Sea Grant researchers successfully combined the strengths of the scientific workflow project, Galaxy, with traditional high performance computing resources and affordable cloud-based data storage that encourages collaboration. As a result, a NGS pipeline has been deployed. The system facilitates broad-based collaboration and distribution by building around the Google Drive cloud storage solution, where the processing of RNA sequences can be both shared and analyzed with a single upload and be reused for multiple purposes.

RECAP:  S.C. Sea Grant researchers at the College of Charleston have developed a streamlined genetic analysis pipeline, allowing broader collaboration and distribution of large quantities of genomics data among current and potential investigators.

FOCUS AREA: The Coastal and Ocean Landscape
Widespread use of ecosystem-based approaches to managing land, water, and living resources in coastal areas. Sound scientific information is available to support ecosystem-based approaches to management and decision-making for the coastal environment.
Title: Phosphorus Key in Nutrient Loading to Residential Stormwater Retention Ponds
Partners: City of Myrtle Beach, Horry County Stormwater Management Program, Town of Surfside Beach, The Parks HOA, Cypress River Plantation HOA Board, Horry County Stormwater Advisory Board, Surfside Beach Stormwater Committee
PI: Smith, University of South Carolina
Project Number: R/ER-38 

RELEVANCE:  The prevalence (>14,000) of stormwater detention ponds in coastal South Carolina may significantly influence the biogeochemical linkages between terrestrial nutrient runoff and organic matter production and fate in the coastal zone.  That many of these ponds are high in algal biomass suggests that organic matter production within these ponds can be substantial.
RESPONSE:  Sea Grant research is underway to quantify the magnitude and fate of this organic matter, which is critical to determining the influence of stormwater ponds on coastal water quality impairment. Key in this regard is the impact that various land uses and current management practices for stormwater ponds have on pond algal productivity and bioavailability of pond-derived organic carbon and nitrogen. 

RESULTS:  Remarkably, pond management practices (specifically, the application of algaecides, typically copper sulfate compounds) had little long-term effect on nutrient – algal relationships, relative to those observed in ponds not subject to chemical treatment.  Since most efforts at pond management are directed at controlling algal growth (typically through intensive application of chemical algicides), study results suggest that education/outreach should focus on informing property owners on the need to limit phoshorus input to ponds. Efforts to ensure proper fertilizer application and to limit sources of excess phosphorus via, for example, outdoor soap/detergent use and pet/wildlife wastes (which are extremely high in P, relative to N) would go far in limiting the need for stormwater detention pond treatments with toxic chemical applications.  Although conventional stormwater ponds are not particularly efficient at removing nutrients coming in from their catchments, results of this study have shown that high algal productivity within ponds effectively convert inorganic nutrients to their organic forms (especially for nitrogen). These high concentrations of dissolved organic nitrogen are then exported to downstream receiving waters when ponds discharge. Discharges of pond-derived organic nitrogen does little to stimulate algal growth in marine receiving waters, which are generally nitrogen limited, but substantially increases the growth and metabolism of natural heterotrophic bacterial communities.

RECAP:  The increased metabolic activity observed in stormwater ponds has the potential to exacerbate low dissolved oxygen conditions present in many of South Carolina’s coastal waters. Indeed, this finding may have direct relevance to the emergence of episodic hypoxia (low dissolved oxygen) in nearshore waters off Myrtle Beach. 

FOCUS AREA: The Coastal and Ocean Landscape
Coastal communities make efficient use of land, energy, and water to conserve the resources needed to sustain coastal ecosystems and quality of life. Sound scientific information is available to support ecosystem-based approaches to management and decision-making for the coastal environment.
Performance Measure: Attendance at Consortium-sponsored ecological services workshops and information events.
Title: Improved SWAN Model for Use in Enclosed Estuarine Environments
Partners: USCG, NIWB NERR, Tom Yawkey Wildlife Center, SC Institute of Archaeology and Anthropology
PI: Voulgaris, University of South Carolina
Project Number: R/CP-18

RELEVANCE:  Evaluating total wave-induced energy in an enclosed estuarine environment can be used to establish a baseline energy level for identifying the effects of human activities on the system, such as boating and associated boat wake-induced energy, a phenomenon more important in estuaries with large ports developed in the upstream. This information would provide coastal managers with a tool for better management of this environment, and will allow for the characterization of suitable environmentally sound locations for the disposal of dredged material. In addition, resource managers will be able to assess the risks, if any, included in the disposal of such material and the potential dispersion away from the disposal location. This will help optimize the costs of dredging with minimal impact on the environment, producing cost-effective navigational channel maintenance and thus a more economically feasible port operation.

RESPONSE:  Researchers set out to identify the total wave-induced energy present in an enclosed estuarine environment, using Winyah Bay, SC as a representative estuarine system. The Simulating Waves Nearshore (SWAN) model, a public domain numerical model, was used to simulate wind-generated wave activity. Although waves depend on wind conditions and local water depth, results suggest that tidal currents also have a significant impact on the distribution of wave energy throughout Winyah Bay, and as such should be included in future studies in enclosed estuaries. 

RESULTS:  Overall, it was found that tidal currents affect the deeper parts of the estuary (i.e., main channels) while the waves affect the shallower parts. Additionally, the current, wave and the wave and current induced bottom shear stress and sediment flux that occurs monthly, seasonally and annually within the estuary was established. This climatology allowed us to identify areas with high and low potential for sediment erosion and accretion.

RECAP:  The improved SWAN model will allow resource managers to (1) assess the impact of boat wakes in estuarine environments and (2) allow for better planning of dredging activities and their impact in estuarine waters. 

Last updated: 6/24/2013 12:03:45 PM
FY12-13 Impacts and Accomplishments – RESEARCH


Page Tools Print this page
E-mail this page
Bookmark this page

Coastal Science Serving South Carolina
Copyright © 2001-2018 South Carolina Sea Grant Consortium
Turbulent Flow Image Courtesy of Prof. Haris J. Catrakis, University of California, Irvine
Privacy & Accessibility