Dr. David Eggleston is an Alumni and University Distinguished Professor at NC State University, and also serves as Director of NC State’s marine laboratory, the Center for Marine Sciences and Technology (CMAST), located in Morehead City, North Carolina. He leads the Marine Ecology and Conservation program at NC State University, which emphasizes testing and refining general ecological theory and concepts in marine systems with the goal that answers will:
(1) make important contributions to our understanding of ecological patterns and processes in marine ecosystems, and
(2) be applied to sustainable management of natural resources and coastal communities.
Research topics over his 36-year career span fisheries ecology, habitat restoration and ecological engineering, conservation biology, deep-sea biology, detecting ecological impacts, behavioral ecology, population dynamics and modeling, and marine science education. Eggleston serves on the advisory boards of state, national and international coastal and marine science organizations. He has been recognized for excellence in research by the National Science Foundation via an Early Career Award, excellence in outreach via an Outstanding Extension Service Award by NC State University, and is a member of the NC Academy of Outstanding Teachers. He loves scuba-diving, boating, fishing, and playing drums in local bands.
SHORT DESCRIPTION OF AREAS OF INTEREST:
I am excited about participating in inter-disciplinary research, extension and education that can take advantage of the CMAST Facility and Programs, as well as my research program to advance the Coastal Resilience and Sustainability initiative forward.
- COMPARISON OF VISUAL SURVEYS VERSUS DREDGING FOR MONITORING BAY SCALLOPS (ARGOPECTEN IRRADIANS) IN SEAGRASS BEDS , JOURNAL OF SHELLFISH RESEARCH (2021)
- Hurricane impacts on a coral reef soundscape , PLOS ONE (2021)
- Metapopulation dynamics of oysters: sources, sinks, and implications for conservation and restoration , ECOSPHERE (2021)
- Seascape ecology: identifying research priorities for an emerging ocean sustainability science , MARINE ECOLOGY PROGRESS SERIES (2021)
- Spatiotemporal Variability in Sedimentation Drives Habitat Loss on Restored Subtidal Oyster Reefs , ESTUARIES AND COASTS (2021)
- Testing ecological theories in the Anthropocene: alteration of succession by an invasive marine species , ECOSPHERE (2021)
- Fish community structure, habitat complexity, and soundscape characteristics of patch reefs in a tropical, back-reef system , MARINE ECOLOGY PROGRESS SERIES (2019)
- Integrating ecosystem services considerations within a GIS-based habitat suitability index for oyster restoration , PLOS ONE (2019)
- Modeling Quantitative Value of Habitats for Marine and Estuarine Populations , FRONTIERS IN MARINE SCIENCE (2019)
- An exotic species alters patterns of marine community development , Ecological Monographs (2018)
Setting attainable oyster restoration targets is necessary to quantify restoration success and recovery of oyster populations and additional ecosystem services that these habitats provide. In North Carolina, oyster cultch planting provides oysters for commercial harvest (i.e. jobs), as well as key ecosystem services that have additional monetary value, such as essential fish habitat. Existing cultch reef monitoring is limited in space and time such that targets established from these data may not be appropriate for optimizing the long-term economic and ecosystem benefits of restoration. Establishing more appropriate restoration targets for long-term persistence of reefs is especially important for increasing reef resilience to fishing pressure and natural disturbances, such as increased freshwater flooding events from coastal storms (e.g., Hurricane Florence). This study aims to establish long-term targets for oyster cultch restoration in North Carolina by (1) assessing the impacts of oyster harvest on habitat complexity, oysters, and fish habitat value, and (2) evaluating the relationship between habitat complexity and reef recovery following harvest. Our overarching hypothesis is that reef resilience and long-term persistence will vary as a function of habitat complexity and location with the (sea)landscape. Our objectives are to conduct a before-after-impact control study to quantify (a) habitat complexity and habitat loss following oyster harvest; (b) oyster density and biomass following harvest, and oystersâ€™ ability to recover from harvest; (c) estuarine fish production and diversity among the reefs and unstructured control sites following oyster harvest using a combination of: (i) gill nets, (ii) fish traps, and (iii) passive acoustic monitoring. The â€œbeforeâ€ component of this study will be represented by data from a 3-year study which evaluated the initial, pre-harvest, oyster and fish response to cultch planting (CRFL 2017-H-063). The proposed study will (1) recommend restoration targets for the NC DMF cultch planting program, (2) generate sound scientific information on the long-term nature and value of ecosystem services provided by (restored) oyster reefs, and (3) support making informed, science-based decisions about the use and management of one of the Stateâ€™s key estuarine restoration programs. The proposed study addresses Objective 1, Strategy 7 described in funding priorities for the NC CRFL program.
Knowledge of connectivity among deep-sea metapopulations is central to predicting population and community dynamics, as well as guiding conservation and understanding biogeographic patterns. Connectivity among metapopulations may be predicted by bio-physical models, and tested with molecular or geochemical tools. However, bio-physical models of dispersal and connectivity require data on larval biology, such as spawning times and locations, pelagic larval duration, vertical distribution in the water column, and swimming patterns. Reliable information on larval biology for deep-sea chemosynthetic organisms is currently inadequate, so biophysical dispersal models have generally relied on untested biological assumptions. The extent and timing of vertical migrations remain unknown for all deep-sea larvae. It is not known, for example, how much of the larval period is spent drifting near the bottom. Dispersal strategies can have profound effects on predictions of metapopulation connectivity. In this proposal, we will model larval transport of select methane seep animals in the Gulf of Mexico to determine why some species are able to disperse around Florida and colonize seeps on the Western Atlantic Margin, whereas others are not. It is hypothesized that interspecific differences in dispersal depth may explain this major biogeographic pattern. Larvae will be sampled using the newly developed SyPRID plankton sampler deployed on the AUV Sentry, and by trapping larvae in year-long deployments of larval collectors on bottom moorings. The work will focus on seep sites at three depths in the northern Gulf of Mexico and at two depths on the Atlantic Continental Margin. Oxygen isotopes and elemental composition of larval and juvenile mollusk shells will be used to obtain independent information about the depths where larvae drift and the variability in dispersal trajectories. Intellectual Merit Reliable connectivity estimates are increasingly important in marine conservation biology and phylogeography as well as metapopulation ecology, yet reliable biological parameters for biophysical models in the deep sea remain unavailable. This project will advance the entire field by using state-of-the-art observations on larval migration, physiology and movements to inform the bio-physical models. The methods will find application not only with chemosynthetic organisms, but also in many other deep-sea environments, including ones that are currently endangered by human activities such as trawling and mining. Broader Impacts In addition to advancing applied fields such as conservation biology and the siting of marine reserves, results will be disseminated through museum exhibits, school programs, curriculum development and social media. The project will contribute to the development of human resources in oceanography by providing postdocs, graduate students, and many undergraduates the practical skills associated with reproductive and larval work at sea, as well as interdisciplinary training in biological, physical, and geochemical oceanography and ocean modeling. Students, including underrepresented minorities, will go to sea and learn the seldom-taught yet essential skill of sorting plankton and recognizing larval forms using morphological criteria.
Channel dredging maintenance of deep-water ports along the U.S. Atlantic and Gulf Coasts is critical to maintaining local, state and regional economies. The expansion of port facilities to accommodate the new generation of large-capacity vessels, as well as the continued development of offshore energy resources, and an increasing frequency and intensity of shoaling from storms, is leading to increasing demand for shipping channel maintenance via hopper dredge. Increasing demand for dredging is leading to scheduling challenges for the U.S. Army Corps of Engineers (US ACOE) due to dredging activities generally being restricted to winter months to avoid impacting protected species such as marine mammals and sea turtles, as well as recreationally and commercially important fishery species. Despite the necessity of dredging for commerce and defense, its potential impacts on the environment are of particular concern as multiple potential stressors associated with dredging activities have been well documented, including direct impacts such as hydraulic entrainment of animals, and indirect effects such as sediment stress (suspended and deposited), release of toxic contaminants, and noise pollution. The overarching objectives of this research program are to: (1) quantify potential impacts of marine dredging on key commercial and recreational fish and shellfish in Beaufort Inlet, NC, (2) communicate the results to key stakeholders including the NC Division of Coastal Management, NC Division of Marine Fisheries, National Marine Fisheries Service, and ACOE to inform decisions regarding mitigation and seasonal closures of dredging to maintain North Carolinaâ€™s State Ports, and (3) provide undergraduate and graduate training with a focus on under-represented and under-served minorities. The proposed research program is innovative because it: (1) Integrates traditional sampling methods, such as trawls which provide measures of relative abundance at discrete times, with application of passive acoustics using underwater hydrophones that can record soniferous (i.e., vocalizing) species 24/7, (2) Integrates with related studies examining changes in water quality during dredging operations (lead by Co-PI B. Puckett), and (3) Provides hands-on-training for graduate students and an explicit training program for minorities.
In North Carolinaâ€™s estuaries, oysters play a critical role as ecosystem engineers, building complex structural habitat upon which an intricate biological community exists. For generations, oysters have provided an important source of food in North Carolinaâ€™s coastal areas, however, only 5-15% of the historic population of oysters remain in North Carolina, though these remaining reefs continue to support a multimillion dollar commercial fishery, as well as valuable recreational fisheries. Management of the stateâ€™s oyster resources is handled by the North Carolina Division of marine Fisheries (NC DMF) through development of a Fishery Management Plan. Currently, the status of the oyster stock is listed as â€œconcernâ€ based on trends in commercial landings and other factors that affect the stock. However, insufficient data exists to fully understand the size of the stateâ€™s oyster resource, level of productivity, and if existing management measures, including trip limits, development of oyster sanctuaries, and replenishment of harvestable areas with cultch (shell), are sufficient to sustain the fishery and habitat oysters provide. Managers must be equipped with timely and robust fishery-independent and fishery-dependent data to accurately assess and sustainably manage oyster populations both for harvest and habitat/ecosystem values. To do so, cost-effective and practical long-term approaches for collecting this information must be designed and implemented. In coordination with The Nature Conservancy, NC DMF and other oyster fishery stakeholders, we proposed to: (1) design statistically robust fishery-independent population survey methodologies for subtidal and intertidal oysters in North Carolina accepted by DMF for incorporation into programmatic biological sampling efforts across the state, (2) pilot the population survey methodology for subtidal oysters and quantify dredge discard/gear mortality in cooperation with commercial oystermen at a 20+ acre natural reef in Pamlico River/Middle Ground as identified by DMF, (3) provide DMF with recommendations on how best to refine the population survey for coastwide implementation and integrate the results into a stock assessment model, and (4) map and illustrate changes in the intertidal oyster population south of Back Sound as determined by deviations in aerial extent.
Production of soft blue crabs Callinectes sapidus, represents one of the oldest aquaculture industries in the US and crab shedding currently contributes substantially to marine aquaculture output in the states of Maryland, Virginia, North Carolina, South Carolina, and Louisiana. While the crab shedding industry in these states as well as others has excellent potential for growth due to the strong market for blue crabs coupled with abundant locations for siting crab shedding operations, expansion soft crab aquaculture along the Atlantic and Gulf coasts has been and continues to be limited by the lack of supply of peeler crabs, which currently are supplied solely via wild harvest. In addition to the inconsistency and unreliability associated with dependence on wild-caught peeler crabs, there is limited information with respect to economic information to support expansion of soft crab aquaculture in the US. Work conducted at the University of Mississippiâ€™s Gulf Coast Research Laboratory has recently established protocols for production of juvenile crabs to stock ponds for the production of peeler crabs. This technology would provide an industry driven solution to dwindling domestic supply and unfilled market demand for soft crabs. We propose to contribute to the NOAA Sea Grant program goals to foster expansion of sustainable aquaculture by: 1) technology transfer of hatchery and pond production to the private sector, and 2) providing a production cost analysis for hatchery, pond, and shedding phases of soft blue crab aquaculture.
As a result of a recent legal settlement, the US Navy and NOAA have initiated a program to characterize soundscapes within NOAA-managed US National Marine Sanctuaries. In support of this program, NOAA/NEFSC will deploy a network of calibrated passive acoustic recording devices within the Florida Keys National Marine Sanctuary to expand understanding and protection of these potentially vulnerable acoustic habitats. These recordings will provide a holistic sampling of the underwater soundscape, capturing anthropogenic, natural abiotic, and biological sound sources. Integration of these acoustic recordings with other data that characterize habitat conditions and species presence, as well as human activity levels in proximity to recording locations, is recognized as being critical to efforts to understand and manage these acoustic habitats. The acoustic monitoring network will include sites within the Western Dry Rocks (WDR), Eastern Sambo (ESB) and Nine-Foot Stake (NFS) reefs within the Florida Keys National Marine Sanctuary (FKNMS). Since early 2017, North Carolina State University (NCSU) has been conducting acoustic monitoring and periodic visual surveys within portions of these reefs, with these studies scheduled to continue through at least the summer of 2019 (Simmons et al., 2018). Through this project, NCSU has developed a set of skilled divers who are trained at conducting visual surveys for habitat and associated organisms, as well as personnel with expertise in the analysis of underwater sound, within the FKNMS. A similar set of visual surveys is needed seasonally at NOAAâ€™s 3 newly established (recordings started in November 2018) passive acoustic monitoring sites (located several hundred meters seaward of the NCSU study sites). Analysis of these newly acquired acoustic data is also needed in order to better understand how traditional visual survey techniques can be used effectively in conjunction with passive acoustic recordings to better manage marine protected areas within the FKNMS, and elsewhere. The objective of this contract is to provide funds to support collaborative work using the existing expertise of the NCSU team in conducting visual surveys within the FKNMS and identifying prominent acoustic signals within the soundscape. This work will improve the ability of NOAA to integrate passive acoustic and visual fish survey data and will move forward our ability to manage and monitor marine sites throughout the Western Atlantic Ocean. This project will take place over a 2 year period from 1st of April 2019 through 30th of March 2021 or starting as soon as the agreement is signed.
As oyster populations have reached historic lows, restoration efforts have expanded worldwide, and there is increasing recognition of the role oyster reefs play in providing key ecosystem services such as removing excess nutrients, stabilizing shorelines and creating essential fish habitat (EFH). The North Carolina Division of Marine Fisheries (NC DMF) conducts two distinct, yet inter-related, oyster restoration programs that involve (1) the creation of no-harvest brood stock reserves that provide larval subsidies (i.e., spat) to fished areas, and (2) cultch-planting to provide substrate for oyster larvae and commercial harvest following a 2-3 year closure. This study will focus on cultch-planting restoration sites, whose value in creating EFH has not been well studied. Our overarching hypothesis is that oyster cultch sites will show enhanced production and diversity of certain recreationally important fish species compared to unstructured control sites, and that fish production and diversity will increase with the complexity of reef habitat. We propose to work with the NC DMF Shellfish/Oyster Program (Garry Wright) to: (1) identify 7-8 oyster cultch sites that vary in habitat complexity (e.g., mounds vs flat reefs vs shell vs marl), as well as several unstructured control sites. We will then (1) map the oyster reefs and quantify their habitat complexity using an Unmanned Surface Vehicle capable of high resolution seafloor mapping, and then (2) quantify estuarine fish production and diversity among the reef sites and unstructured control sites using a combination of: (i) gill-nets, (ii) fish traps, (iii) hydrophones, and (iv) possibly a Didson acoustic transducer. The hydrophones will record species-specific fish vocalizations 24/7, which is a tremendous compliment to periodic surveys with nets and traps. The proposed study addresses two overarching Objectives and four Specific Strategies described in funding priorities for the NC Coastal Recreational Fishing License (CRFL) program. Examples range from (i) Quantifying linkages between coastal fish habitat and fish production, to (ii) Evaluation of the success of restoration/enhancement projects, to (iii) Research into restoration techniques to maximize long-term ecological function.
This study will determine the value of oyster cultch reefs as essential fish habitat and quantify the contribution of cultch reefs to overall fish production per unit area. Our overarching hypothesis is that oyster cultch sites will show enhanced production and diversity of certain fish species compared to unstructured control sites, and that fish production and diversity will increase with the complexity of reef habitat. For example, cultch-planting sites could serve as important habitat for juvenile and sub-adult stages of recreationally and commercially important black sea bass (Cetropristis striata), gag grouper (Mycteroperca microlepis), and sheepshead (Archosargus probatocephalus), as well as adult stages of highly targeted speckled trout (Cynoscion nebulosus), weakfish (Cynoscion regalis), red drum (Sciaenops ocellatus), and tarpon (Megalops atlanticus). As oyster populations have reach historic lows, restoration efforts have expanded worldwide, and there is increasing recognition of the role oyster reefs play in providing key ecosystem services such as removing excess nutrients, stabilizing shorelines and creating essential fish habitat. The North Carolina Division of Marine Fisheries (NC DMF) conducts two distinct, yet inter-related, oyster restoration programs that involve (1) the creation of no-harvest brood stock reserves that provide larval subsidies (i.e., spat) to fished areas, and (2) cultch-planting to provide substrate for oyster larvae and commercial harvest following a 2-3 year closure. Coastal habitat management and policies require information on ecosystem services provided by structured habitats (e.g. oyster reefs, mangroves, seagrass, salt marshes, coral reefs). Sanctuary reefs have successfully contributed to oyster population growth in NC, as well as increased diversity and abundance of commercially and ecologically important reef associated species such as weakfish, Atlantic spadefish, and spot. Cultch planting provides oysters for commercial harvest (i.e. jobs), as well as key ecosystem services that have additional monetary value; however, we are unaware of any information on the EFH value of oyster cultch-planting programs. Within NC, cultch-planting sites are 1-2 orders in magnitude greater in area than the current network of no-take reserves. Moreover, funding for oyster restoration is increasingly viewed through the lens of EFH.
The objective of the proposed work is to evaluate the potential for bay scallop aquaculture in North Carolina as a means to diversify and strengthen the stateâ€™s shellfish aquaculture industry, as well as using aquaculture produced animals as a tool to restore wild stocks. There are two main components of the proposed work: (1) Aquaculture production trials, and (2) Field restoration trials using hatchery-reared scallops.
North Carolina includes over 16,945 km of estuarine shoreline, 87% of which are included in the Albemarle-Pamlico estuarine system (APES). These shorelines are dominated primarily by marsh habitats, which provide a number of ecosystem services, including supporting North Carolinaâ€™s commercial and recreational fishing industry and providing shoreline stabilization in response to storms. Sea-level rise, coastal inundation, and shoreline hardening are leading to declines in coastal marsh ecosystems. Invasive species may further exacerbate marsh habitat loss by displacing dominant native species and decreasing biodiversity. In particular, the invasive marsh-grass, Phragmites australis (hereafter: Phragmites), can outcompete native marsh-grass, Spartina alterniflora (hereafter: Spartina), resulting in large scale and often-expensive eradication efforts1. The effects of Phragmites on the provision of ecosystem services have been mixed, with studies showing positive (increased carbon accumulation), negative (decreased plant biodiversity), or neutral (abundance and diversity of higher trophic levels) effects. Models that predict shoreline erosion or fisheries nursery production require accurate information on how invasive versus natural marsh grass influence these processes; especially in a shallow, wind-driven estuaries such as the APES. We propose an inter-disciplinary research project that begins to assess the interacting effects of invasive marsh grass distribution and wave energy on shoreline erosion and essential fish habitat availability. Specifically, we propose to quantify (1) shoreline erosion and (2) shallow detrital habitat as a function of the (i) percent cover of native versus invasive marsh grass, and (ii) predicted wave energy. Shallow detrital habitats that are found adjacent to marsh shorelines in Pamlico Sound provide important nursery habitat for recently settled blue crabs. The proposed research team consists of a Marine Ecologist (PI: Erin Voigt, NCSU PhD. Student in marine science), a Fisheries Ecologist with experience working on blue crab ecology and ecosystem services of Phragmites (Dr. David Eggleston, NC State and Director of CMAST), as well as experts in the application of Unmanned Aerial Systems to habitat surveys (Dr. W. Showers, NC State and Director of the River Net program; Dr. David Johnston, Duke University and Director of Dukeâ€™s Robotics and Remote Sensing Group). The study system will focus on a 110km section of meteorologically dynamic shoreline in Croatan and Pamlico Sounds (Figure 1a), known to (i) have a mix of Spartina and Phragmites dominated shorelines, (ii) be a major settlement area for blue crabs and (iii) predicted to be highly vulnerable to shoreline erosion due to coastal inundation.
- Expertise: Climate/Environmental Change
- College: College of Sciences
- Themes: Coupled human and natural systems
- Expertise: Education
- Themes: Education at NC State and beyond
- Expertise: Marine and Aquatic Ecosystems
- Expertise: Modeling
- Themes: Sustainable agriculture, forestry, and rural, natural resource-based economies
- Expertise: Water Quality
- Themes: Water quality and quantity in the coastal zone