2022 Coastal & Estuarine Summit
Hosted by Restore America's Estuaries
New Orleans, LA | December 4-8, 2022
Science, Technology, and Practice
Mon, 5 Dec, 17:30 - 19:30 Central Time (UTC -5)
Location: Poster Hall
Track: Science, Technology, and Practice

Advancing the Science of Coastal Ecosystem Restoration

Christopher Miller, USDA-NRCS Cape May Plant Materials Center
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The development/release of conservation plants to commercial seed and nursery markets has traditionally been a high priority of the USDA-NRCS Plant Materials Program (PMP). While plant development remains an important function, emphasis on it is expected to lessen as a greater variety of desirable conservation plants become commercially available. Subsequently, the focus of the PMP has shifted to plant technology development. Direct Seeding Smooth Cordgrass for Tidal Shoreline/Marsh Stabilization: A marsh islands restoration project in Jamaica Bay, NY was conducted by the Army Corps of Engineers in coordination with the Cape May Plant Materials Center (PMC). Over 150 acres of marsh island habitat was restored with appropriate tidal marsh species and successful smooth cordgrass direct seeding methods were developed. Wetland Plants Salinity Tolerance Screening: Trials to develop standardized protocol assessing plant salinity tolerance in controlled greenhouse studies were conducted using automated hydroponic systems to subject plants to treatments of varying salinity concentrations. Preliminary trials examined Southampton Germplasm prairie cordgrass with plans to repeat the trial methods testing other PMP conservation plant releases. The primary goal of these trials is to determine appropriate plant recommendations for living shoreline restoration applications and use on marginal farmland to mitigate the impacts of saltwater intrusion due to climate change. Saltmeadow Cordgrass Variety Performance Study: PMC staff initiated a study to examine the performance of a local and two southern saltmeadow cordgrass varieties. Findings from this study could help distinguish the best performing variety for coastal restoration applications and NRCS practice standards in the Mid-Atlantic region. Improving Plant Diversity of Living Shoreline Plantings: Grasses and grass-like plants provide the primary stabilization for living shorelines. Including adapted flowering forbs and wildflowers provides additional ecosystem services. Seaside goldenrod, amberique-bean, and Virginia saltmarsh mallow are species under evaluation for shoreline planting applications.

Greening Up Gray Shorelines: Implementing a Green Bulkhead as a Means of Ecological Uplift

Taylor Beck, DNREC Division of Coastal, Climate and Energy
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Bulkheads are built to control erosion, but the installation of this gray infrastructure along tidal wetlands reduces marsh habitat and the associated ecosystem services marsh habitat provides. Green bulkheads can uplift the ecological value of the space by adding native marsh plants and creating functional habitat for intertidal organisms. Delaware Department of Natural Resources and Environmental Control, Delaware Coastal Programs installed phase I of a green bulkhead project in front of an existing bulkhead in Little Assawoman Bay, Delaware. The design is an interpretation of a marsh organ structure in which PVC are installed in rows of declining height to accommodate tidal fluctuations. PVC were lined with natural burlap, filled with sand, and planted with smooth cordgrass (Spartina alterniflora). We anticipate growth of the planted smooth cordgrass and potential recruitment of other plants and epifauna. Data will be collected April – October 2022 from the green bulkhead site, a bare bulkhead reference site, riprap, and natural marsh. Data collected will include scour patterns in and around the green bulkhead, vegetation growth, benthic epifauna and nekton species richness and abundance. Adaptive management strategies applied to the second installation phase (Fall 2022) as well as the results of data collected over the 2022 growing season will be presented. Erosion control and flood protection is becoming increasingly necessary, especially in areas with high erosion rates where living shorelines are not feasible. Green bulkheads may be a way to restore some functional ecological value to a gray area that is needed for shoreline stabilization. We hope to provide information and helpful strategies for how green bulkheads may be applied in other places as a means of ecological uplift.

Flooding Impacts of Hurricane Ian in Charlotte Harbor (Florida): What Was the Mitigation Role of Coastal Wetlands?

Megan Kramer, University of South Florida
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Over a third of the global population is concentrated within 100 km of the coast, with some of the fastest growing megacities located next to deltas. This concentration of development along our coastlines exposes dense human populations to coastal hazards such as storm surge and tropical storm winds, while also altering the natural landscape and reducing associated ecosystem services. Coastal wetlands such as mangroves have been recognized for their ability to attenuate wave energy and reduce inland flooding, though mangrove cover continues to decline globally. In this study, we evaluate a 2-dimensional hydrodynamic model of Charlotte Harbor during Hurricane Ian (2022), which passed through Port Charlotte as a Category 4 hurricane. The model, developed in Delft3D FM, features a high-resolution flexible mesh with grid lengths ranging from approximately 15 to 300 meters. Water level sensor data deployed before the storm by USGS, high water marks, and aerial imagery collected after the storm are used for model verification. We compare inundation levels and water velocity magnitudes in urban areas with and without mangrove forest buffer. Simulation results demonstrate the value that coastal wetlands serve for flood mitigation and indicate the potential role that wetland restoration and design may play in protecting tropical and subtropical regions from future extreme weather events.

Living Shoreline Solutions with Tied Concrete Block Mat

John Slupecki, Motz Enterprises, Inc.
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The focus point for this poster is the evolution of the living shoreline. The project is a repair using tied concrete blocks to repair sections of an oyster bag living shoreline. Oyster bags, and shells are not as available in many areas and a solution is needed that will also work with newly developing oyster spat. This project highlights on how to build a living shoreline that isn't just for low energy areas. The site is located within a tidal marsh of Sapelo Island, GA. Sapelo is a state-managed barrier island, the fourth largest in the chain of coastal Georgia islands between the Savannah and St. Marys rivers. Accessible only by passenger ferry, Sapelo provides a number of public access recreational, educational and lodging opportunities. The project was completed in Early 2022 by Zulu Marine and Aerial with the oversight of the Georgia Department of Natural Resources (DNR), who manages the island. Motz Enterprises, Inc. is the manufacturer of the tied concrete mat called Flexamat. The company has been in business for over 30 years and is headquartered in Cincinnati, Ohio with multiple regional manufacturing facilities. We developed the first tied concrete block mats with the technology to manufacture and package concrete erosion mats into rolls. Through our experience in a wide range of environments, we have pioneered successful methods to achieve fully vegetated concrete erosion mats. www.flexamat.com

Living Shoreline and Oyster Reef Creation to Improve Water Quality and Resiliency along Forked River Beach, Lacey Township, NJ

Capt. Al Modjeski, American Littoral Society
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Historically, Barnegat Bay had over 12,000 acres of eastern oyster (Crassostrea virginica) beds. Yet today, nearly the entire natural oyster population is gone. With their elimination, Barnegat Bay not only lost the oysters themselves, but the ecosystem services they provided such as water filtration, wave energy mitigation, and nursery habitat. Funded by NJDEP, this restoration 1) Restored, enhanced, and protected 2,600 linear feet of shoreline with living shoreline oyster reefs, 2) Incorporated current outreach programs and stakeholder meetings to maintain project cohesiveness, and 3) Established a long-term volunteer program and public/private partnership to improve public and community awareness and protect reef resources.

Implementing Oyster- and Natural Fiber-based Living Shoreline Approaches to Reduce Shoreline Erosion and Saltmarsh Habitat Loss in South Carolina, USA in order to Increase Coastal Resiliency

Graham Wagner, South Carolina Department of Natural Resources
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Estuaries form one of the predominant landscapes of the coastal zone in South Carolina, consisting of interconnected networks of intertidal salt marshes (predominantly Spartina alterniflora) often protected by fringing intertidal oyster (Crassostrea virginica) reefs that serve as natural breakwaters. Coastal salt marshes are, however, being lost at a higher rate than any other wetland habitat due to the synergistic effects of sea level rise, habitat degradation, coastal development, and shoreline hardening. Such loss is of concern as salt marshes represent one of the most biologically valuable habitats in the coastal region, supporting a suite of critical ecosystem services that cannot be achieved through the installation of sea walls and bulkheads that disrupt the land-water continuum and that are unable to adapt to sea level rise. In efforts to address salt marsh habitat loss, restore ecosystem services, and increase coastal resiliency, researchers at South Carolina Department of Natural Resources’ (SCDNR) Marine Resources Research Institute (MRRI) have been conducting experimental scale living shorelines research to assess the effectiveness of nature-based solutions. Researchers at SCDNR have developed effective methods to install living shoreline materials that attract oyster larvae and rapidly create new 3-dimensional reef habitats. These living shorelines reduce wave energy, which facilitates sediment capture, and increases the elevation landward of the reefs. Over a longer timeframe, naturally occurring marsh grass fills in behind the reef in a manner similar to natural salt marsh proliferation. Monitoring these installations and quantifying metrics of success have facilitated improvements to material selection and workflows and to the implementation strategies that have achieved shoreline stabilization and habitat creation in a threatened coastal environment. This presentation will showcase some successes from this work across a range of environmental conditions.

Restoring Ecologically Beneficial and Resilient Infrastructure at the Mouth of the Maurice River

Shane Godshall, American Littoral Society
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The American Littoral Society and its partners are working on a project to protect the inlet of the Maurice River (Cumberland County, NJ), the most economically important river on Delaware Bay, using proven living shoreline methods. Erosion throughout the river mouth has made it unsafe and ecologically damaged while impeding economic growth. Our project will provide improved resilience and ecological value to the mouth of the Maurice River by protecting the marsh vulnerable to erosion while creating new intertidal habitat. By employing a combination of hybrid breakwaters and oyster reef/ribbed mussel beds along with salt marsh restoration, this project will achieve storm protection of fragile and rapidly eroding shorelines that shelter the port and surrounding communities. Work will be conducted in three phases. Phase I will involve the creation of a 600’ planted, hybrid rock revetment; Phase II will create 2,025’ of hybrid living shoreline breakwaters and subtidal oyster reefs/ribbed mussel beds placed landward of the breakwaters; and Phase III will create 4,600’ of hybrid living shoreline breakwaters and oyster reefs to reduce the wave energy impacting an adjacent dike and allow for the recovery of low marsh. Overall, the creation of the hybrid living breakwaters and revetment will protect infrastructure and surrounding communities, provide ecological uplift, and sustain economic activity.

Examining Sediment Contaminant Levels in Living Shorelines in Comparison to Both Natural and Armored Shorelines in Galveston Bay, Texas.

Ryan Gilbert, Lee College/University of Houston-Clear Lake
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Despite extensive efforts to armor coastal areas in the United States with concrete, vinyl, and metal bulkheads, problems such as subsidence, flooding, and shoreline stabilization persist, and in some cases, have been exacerbated by shoreline armoring. Living shorelines, or shorelines engineered to mimic natural shorelines, have emerged as a popular combatant against coastal squeeze, a process in which encroaching land development coupled to armoring leads to the loss of wetlands and the associated ecological services. An often-mentioned ecological service provided by natural shorelines is their ability to filter water by sequestering chemicals from the water column to the sediments. However, this function has yet to be quantified in living shorelines. Along the Texas coast, where subsidence and shoreline erosion rates are among the highest in the world, there have been over one hundred living shoreline projects developed on coastal properties, with minimal comprehensive scientific research to evaluate whether or not these engineered shorelines are functioning similarly to natural shorelines. Research regarding contaminants in living shoreline sediments is novel and extremely critical to understanding how these environments might influence the distribution of contaminants in estuarine systems. This study examined the concentrations of selected heavy metals and organic pesticides in living shoreline sediments and compared them to both natural and armored shorelines to test the hypothesis that living shorelines are more similar to natural shorelines than armored shorelines in terms of sequestering contaminants. Results from ICP-AES and GC-MS analysis of fifty-four (54) sediment cores collected from shorelines in the Galveston Bay system indicate the relationship between shoreline type and contaminant concentration may be obscure and contaminant dependent.

Examining Sediment Macrobenthic, Microbial, and Nekton Communities in Living Shoreline Restoration Sites in Galveston Bay, Texas

Myrah Urquidez, Lee College/UHCL
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Artificial bulkheads are a popular means of erosion control, but they have significant drawbacks. Restoring marsh grasses along shorelines is an alternative method of erosion control that also provides numerous ecological benefits. Living Shorelines are small-scale restored marshes that can be installed near homes and businesses. Our study evaluates the ecological functions of Living Shorelines. Benthic macroinvertebrates are reliable indicators of ecosystem health, as they respond predictably to stress and pollutants in the aquatic environment. Marsh ecosystems provide habitat to nekton that are valuable for food and sport. The marsh microbiome plays an important role in supporting a rich ecosystem, because microbes regulate many biogeochemical processes. This study tests the hypothesis that Living Shoreline sites are more ecologically similar to natural marsh sites than bulkhead sites. The hypothesis was tested by gathering data on benthic macroinvertebrates, nekton, and the microbiome. Data were collected from Living Shorelines, armored shorelines, and natural shoreline sites in Armand Bayou, Trinity Bay, and West Galveston Bay on the upper Texas coast. Sediment samples were collected and analyzed to characterize and compare the benthic macroinvertebrate and microbial communities, while modified minnow traps were used to assess the nekton community across these sites. The data partially supports the hypothesis: The abundance of benthic macroinvertebrates are higher in abundance and similarity between living shoreline and reference sites, whereas bulkhead samples are significantly lower in abundance. However, data on nekton suggest variability that may be affected by factors beyond those examined in this study. Microbial abundance data are in line with the findings of the benthic macroinvertebrates; microbial representations in several undisturbed Living Shoreline sites appear more similar to those found in natural marshes than in artificial bulkheads. The relative abundance of nitrogen cycling microorganisms in all Living Shoreline sites is also consistent with this trend.

Examining Shoreline Stability and Restored Plant Communities of Living Shorelines in Galveston Bay, Texas

Ashley Van Wieren, Lee College/UHCL
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The shorelines of Texas beaches, bayous, and bays are increasingly impacted due to erosion, sea level rise, and climate change. A common solution to the problem of retreating shorelines has been to armor shorelines using artificial bulkheads. However, armored shorelines break down over time, increasing erosion on adjacent shorelines, and negatively impacting plant abundance and diversity. An increasingly popular alternative for erosion control is living shorelines, which utilize natural plant communities to protect the shorelines of homes, parks, and other individual sites. Living shorelines provide habitats for recreationally and economically important species. Implicating effective methods to preserve and restore natural shorelines may lead to increased species diversity, improved water and sediment quality, and gain of public and private lands. This study tests whether living shoreline sites effectively stem shoreline erosion while being more ecologically similar to natural shoreline marsh sites than armored sites. Geospatial and plant community data were collected from restored, armored, and natural reference shorelines in the Galveston Bay system. Plant communities were examined by measuring: species diversity, percent coverage of each species, individual stem counts for each species, Spartina alterniflora biomass, and chlorophyll levels. Drones, equipped with natural color and color-infrared cameras, were used to capture low altitude aerial imagery at each site. This imagery was combined with GPS data to assess elevation and shoreline location at each site. This method is also being investigated as a means to provide low-cost seasonal data at each site, such as percent plant coverage and species composition. Results suggest plant communities are undergoing successional processes, approaching functions similar to native shoreline habitats, and are stabilizing erosion at living shorelines.

Restoring Piping Plover (Charadrius Melodus Melodus) Habitat using Living Shorelines and Nature-Based Solutions

Kirsten Ellis, CBWES Inc.
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Near Shippagan, New Brunswick, Canada, an exciting project is leveraging salt marsh creation and sand engine techniques to create and improve nesting habitat for the endangered Piping Plover. This project is the first sand engine in Atlantic Canada and the most northern created marsh with sill to date. The barrier spit, where the project is located, and its habitats have been altered and degraded by more than a century of human activity. In 2020, construction began on the sand engine which included the beneficial reuse of sediment dredged from the adjacent channel. The marsh and marsh sill are scheduled to be built in Fall 2022 using rock from seawalls that are being removed from the site and historic (1983) dredge material present on the site. The project also encompasses dune restoration, a fifteen year monitoring program, and five year scientific research program which includes two Masters and one PhD level research projects. Year 1 post-construction monitoring of the sand engine showed increases in beach elevation to elevations that are within the range of those seen at a nearby reference beach where Piping Plovers successfully nested in 2020 and 2021. Increased beach width and shoreward migration of the dune toe and dune vegetation were also observed. Year 2 and as-built monitoring of the sand engine and created marsh, respectively, is ongoing. This project is the result of a collaborative effort that includes federal and provincial government departments, private industry, academia, and environmental NGOs.

Jean Lafitte Shoreline Protection Project: Modifying Shoreline Energy Conditions to Restore Submerged Aquatic Vegetation

Thomas Cancienne, Stantec
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The Jean Lafitte (JELA) Shoreline project is an important project for Louisiana and the Gulf of Mexico area as it is needed to protect, enhance, and restore the Submerged Aquatic Vegetation (SAV) within the Barataria Basin. SAV is an important component of the predominantly freshwater Lake Salvador and Cataouatche ecosystems. These estuarine lakes lie in the upper Barataria Basin of the Mississippi River’s coastal delta, and they border Jean Lafitte National Historical Park and Preserve’s Barataria Preserve on its west. SAV provides habitat and food for aquatic biota, and its productivity contributes to the robust fisheries in these deltaic coastal waters. SAV beds also attenuate storm energy and reduce erosive impacts on adjacent terrestrial wetlands. The intent of this “living shoreline” is to create a multi-layered system approach combining engineering design with ecological design criterial drivers. A successful living shoreline is one where the entire system is working together to reflect the natural ecosystem and match existing project conditions, through structures, nourishment, water quality, SAV habitat, alignment, orientation, and elevation. Engineering with nature provides the most robust and sustainable project for ecosystem protection.

Coastal Restoration Activities at MacDill Air Force Base

Tiffany Lane, U.S. Fish and Wildlife Service
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Coastal restoration projects at MacDill Air Force Base (MAFB), located in the Tampa Bay estuary system, have been implemented for several decades and range from the manipulation of current hydrology to reflect historic patterns to the removal of mosquito ditch spoil mounds and ditches. Restoration has focused on removing these spoil mounds to achieve two primary goals:  1. upland habitat (spoil mounds) restored back into mangroves and 2. reestablishing natural flow patterns. To remove the mounds, we use an innovative method called hydroblasting which utilizes pumps and high-pressure fire hoses to reduce the height of the mounds to foster mangrove recovery while preventing invasives from returning. Hydro-blasting equipment has a very low “footprint” verses heavy equipment within the mangrove forest. To date, the base has removed over 480 spoil mounds that has resulted in the restoration of 52 acres of mangrove forest. This poster will inform the group of these innovative restoration techniques and ongoing efforts to restore mangrove swamp and imperiled saltern communities and restore a historic hydrologic flow to Tampa Bay.

Application of a Novel Living Shoreline Model to Compute Ecosystem Restoration Benefits

Emma Dodsworth, Virginia Institute of Marine Science/ William & Mary
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Living shorelines are nature-based coastal adaptations, which have become important replacement habitats for natural marshes lost to sea level rise, erosion, and coastal development. Unlike hardened shorelines, these constructed habitats can leverage natural ecological processes to keep pace with rising sea levels, maintaining their benefits under climate change. This form of shoreline restoration provides watershed-scale benefits across natural and human communities, improving the ecosystem services of the shoreline. Living shorelines are approved as a best management practice (BMP) around the Chesapeake Bay watershed to reduce nutrient and sediment loads in an effort to restore the estuary. However, there are no tools available to compute site-specific nutrient and sediment removals for these restoration practices. Our research will create a widely applicable and directly accessible model for local stakeholders to assess nutrient and sediment removals from different living shoreline designs. This simulation model of living shorelines is being validated with seasonal observations from diverse living shorelines. Seasonal observations will be completed summer of 2022 and model development will start fall of 2022. The model will be used to compute nitrogen removals for representative sites in the lower Chesapeake Bay and will be provided online for stakeholders (restoration planners, resource managers, local government, etc.). Other educational materials (e.g., fact sheets, brochures, websites, videos) will be developed in collaboration with partners to facilitate the use of the model to promote multi-benefit shoreline restoration projects.

Preliminary Results from the Upper Galveston Bay Sustainable Oyster Reef Restoration Project: the Influence of ENSO on Monitoring Results and Project Performance

William Rodney, Texas Parks and Wildlife Department
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The Upper Galveston Bay Sustainable Oyster Restoration Project is a partnership between The Nature Conservancy, Texas Parks and Wildlife Department, and the Galveston Bay Foundation where partners restored ~25 acres of harvestable oyster reef and ~13 acres of “sanctuary” reef (protected from oyster harvest) in upper Galveston Bay, Texas. This creates a “source-sink” dynamic where the protected broodstock within the sanctuary reef (“source”) supply larvae to the harvestable (“sink”) reefs. Quarterly monitoring was conducted to assess restoration success and inform adaptive management and future design of other similar “landscape-scale approach” restoration projects. Monitoring results indicate that seasonality and salinity regime can impact short-term project success, but long-term success can be achieved as natural salinity and climatic cycles shift to favorable conditions. The project’s location experiences wide fluctuations in salinity driven by the ENSO (El Niño/Southern Oscillation) cycle in the Eastern Equatorial Pacific. During El Niño periods, increased rainfall can depress salinity, while La Niña periods produce drought conditions causing salinity to increase. Construction of the reefs occurred in early 2021 during an El Niño period and the persistence of low salinity conditions in the area caused concern about the project’s success, as spat and oysters were absent from the restored reef. In 2022, a shift to La Niña conditions caused salinity to increase resulting in increased oyster and spat abundance on the restoration sites. No additional adaptive management strategies (e.g., additional cultch placement or seeding) were required to overcome short-term apparent failure; the reef naturally recruited oysters when conditions improved. Not only can the results of this study inform the timing of cultch placement for oyster restoration projects, but it also indicates that long-term monitoring may be required to adequately assess project success in areas with highly variable climatic and salinity regimes.

Shoreline Loss of Historical Importance: Using 210Pb and 137Cs to Calculate Sediment Accumulation

Sarah Ashley, University of North Carolina Wilmington
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The United States’ East Coast is at increasing risk of degradation and devastation as a result of factors associated with climate change. Common among these threats are rising relative sea level, nuisance flooding, and tropical cyclone storm events, augmented both in frequency and severity. Due to their position in the landscape, salt marshes are often the first area to be impacted by storms. Many salt marshes are considered ecotones, or, boundaries between two systems. Ecotones are transitional ecosystems, and typically appear wedged between a riverine or marine environment and a terrestrial ecosystem. Areas experiencing sea level rise alongside anthropogenic effects are at a greater risk for marsh erosion. As these marshes retreat laterally in response, the dynamics of the ecosystem effectively change. The retreating marsh becomes transgressive, encroaching into adjacent terrestrial ecosystems, which can cause significant impacts to agricultural or developed land and forests. Brunswick Town Fort Anderson is a local historic site bordering the Cape Fear River. The site is experiencing high rates of shoreline loss which is threatening the very survival of many historic artifacts and fortifications. This study examines the relationship between anthropogenic effects and paleotempestology and their combined effects on the marsh’s formation and the processes that drive its development. Specifically, how do the effects of paleotempestology and anthropogenic impacts affect sediment accumulation rates and the marsh’s ability to keep pace against rising sea level?

Documenting >40 Years of Benefits Derived from Nature-Based Wetland Creation Projects

Jacob Berkowitz, U.S. Army Engineer Research and Development Center
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Dredged sediments are increasingly used to create and restore wetlands in support of the Engineering With Nature (EWN) initiative. However, few studies quantify long-term EWN outcomes. In response, we reconstructed >40-year-old studies at historic dredged sediment wetland creation sites. Results demonstrate that over decadal time periods wetland features designed using EWN principles (nature-based features, natural processes) provide a range of ecological functions (energy dissipation, nutrient cycling) and associated goods and services (flood risk reduction, improved water quality). Notably, beneficial ecosystem goods and services were coupled with ecological functions derived from physical (energy dissipation), biogeochemical (denitrification), and habitat processes which operate at varying timeframes and magnitudes. As a result, physically dominated ecological functions and associated goods and services are delivered more quickly (weeks to months) than those requiring establishment of plant communities (years to decades) and other biologically mediated processes. Additionally, success criteria should focus on measures of ecological function and avoid over-emphasizing inappropriate comparisons with un-altered, mature reference areas. Incorporating these considerations in an Engineering With Nature context delivers highly functional, sustainable, and persistent environmental and societal benefits when restoring and creating wetlands.

Created Wetlands for the Reduction of Organic Loading, a Case Study at Myrtle Grove, LA

Robert Lane, Comite Resources
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The CHS Inc. Grain Export Terminal in Myrle Grove, LA operates under various federal and state permits, one of which is a LDEQ Water Discharge Permit that allows the discharge of stormwater runoff from the facility into Bayou Dupont with a limit for TOC of 50 mg/L daily maximum, however, average TOC concentration was 83 mg/L in 2007-2008. In an effort to comply with the LDEQ Water Discharge Permit, Comite Resources designed and directed construction of two ~2-acre stormwater wetlands directly north and south of the facility in the winter of 2011-2012 for the purpose of reducing total organic carbon (TOC) concentrations of surface water flowing from the facility. During March 2012, approximately 800 bald cypress seedlings were planted in the two wetlands, and herbaceous species, such as cattail mixed with pickerelweed, smartweed, arrowhead, and bulltongue colonized the wetlands naturally. Alligators and a large population of whistling ducks, along with other wildlife are also currently using the wetlands. Water quality greatly improved, with a 70% decrease in TOC and an 89% decrease in TSS as stormwater flowed through the primary wetland to the north. Bald cypress trees grew rapidly, with a mean annual diameter growth increment of 2.2 cm/yr and a mean tree biomass at the end of the 10-year study of 182±11 kg/tree. The CHS facility has been in compliance with its LDEQ discharge permit since the stormwater wetlands were constructed.

Where Are We Now? Integrating Site-Specific Observations and Modeling to Manage a National Preserve in the Mississippi River Delta

Julie Whitbeck, Jean Lafitte National Historical Park and Preserve
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Located in a subsiding delta lobe of the Mississippi River, the Barataria Preserve protects 26,000 acres of primarily freshwater wetlands in the upper Barataria Basin. Its highest terrain is the natural levee ridges of two former Mississippi River distributaries, yet most of its landscape lies less than 0.5 m above sea level. Combined with modern era isolation from River sediment resources, natural subsidence and global sea level rise are causing rapid increases in flooding depth and duration across the Preserve landscape (approaching 1 cm per year). To inform effective stewardship of natural and cultural resources and to guide fiscally-responsible planning and management of Preserve infrastructure over the next 50 years, the park commissioned a future conditions modeling project to forecast surface elevation, flooding extent, salinity and vegetative cover under a suite of 12 different climate and coastal management scenarios. With model projections in hand, now the park wishes to link actual observations of changing conditions with model output to evaluate which model scenario best represents realized change and to document landscape transformation as it occurs. We are developing a rudimentary spatial database that will enable park managers to visualize and compare actual observations and model-projected values of salinity, water depth, surface elevation and vegetation type at locations across the Preserve landscape, including the areas of most intensive infrastructure development and public use. Here we describe our tool and we illustrate its use with model projections and salinity observations from long-term water quality monitoring. We also highlight gaps between our idealized vision of this management-informing tool and what we have developed, and we identify a few challenges of delivering management-relevant scientific information to non-experts whose decisions are subject to public scrutiny.

Development and Deployment of a Long-Term Benthic Oxygen Flux System

Jeff Coogan, Woods Hole Oceanographic Institution
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Measuring long-term oxygen production and respiration rates for seagrasses has long been limited to a few sample points across the seasonal scale. These methods can be very labor intensive and subjected to uncertainty associated with short term variability over the measurement intervals. To better understand this variability, we built and deployed a long-term benthic oxygen flux system. The system consists of a fixed bottom lander that measured the oxygen eddy covariance and a surface buoy that transmits real time data and power. The system was deployed in Massachusetts in an Eelgrass (Zostera marina) meadow and collected continuous benthic oxygen flux data from May 2021 to October 2021. Ongoing analysis shows a range of seasonal changes and variability over short-term events. Accompanying measurements of photosynthetically active radiation and above ground biomass allow for a more detailed analysis of changes in water temperature, morphology, hydrodynamics and the associated changes in light use efficiency. Several technical challenges were also encountered during the deployment and provided an opportunity to advance the reliability of this system for long-term seasonal deployments.

The Adaptation of the Ecodisk to Maximize Wave Attenuation & Ecological Benefits

Phillip Todd, Atlantic Reefmaker
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The need for coastal resilience in relation to storms and sea level rise continues to be a national priority. Adaptation and refinement of best management practices are keys to improving sustainability and achieving long-term project success, and in many cases a product’s, success. Several clients chose to install Atlantic Reefmaker with its many natural and nature-based characteristics to achieve their project’s goals related to wave attenuation and habitat enhancement/restoration? within minimal footprint. With each new project, design consultants and staff have worked to adapt the ecodisks to achieve our client’s varied goals and objectives. The first challenge came with the Bonner Bridge Seagrass Mitigation Project. The Reefmaker technology was selected to attenuate wave energy and thereby promote seagrass coalescence in the high energy wave environment of Pamlico Sound, North Carolina to achieve a compensatory seagrass mitigation requirement. Construction of the mitigation project was completed in January 2017 utilizing 101 fiberglass piles with square-shaped ecodisks, which had 20% porosity, which was the original design. This innovative project was included in An Atlas: Volume 2, a publication of the Corps Engineering with Nature® program. Since the Bonner Bridge Seagrass Mitigation project, Atlantic Reefmaker has adapted the ecodisks in shape, size, texture, and porosity to increase wave attenuation, reduce materials cost and promote biological colonization. The ecodisks have been scaled to low as well as high energy environments. Octagonal-shaped, textured ecodisks with 0% porosity have also been deployed. Maybe mention another project example here which used a different version of the units.

Application of Unmanned Aerial Systems and Imagery Analysis in Classifying Coastal Marsh Vegetation and Habitat

Seth Chapman, Louisiana State University Department of Oceanography and Coastal Sciences
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Louisiana’s coastal marshes have experienced widespread decline over the last century and government agencies have worked to offset land loss through marsh creation projects. However, standardized post-construction assessment of created marshes requires considerable cost, time, and logistical effort. The aerial imagery collected using Unmanned Aerial Systems have the potential to complement standard monitoring by reducing logistical costs and increasing the spatial scale of post-construction assessments. To explore this possibility, we are using in-situ vegetation sampling to calibrate and validate multi-spectral imagery and compare vegetation communities among created and reference brackish marshes in Barataria Bay, Louisiana. In May 2022, we conducted quadrat vegetation sampling and collected multi-spectral imagery from two created marshes and three reference marshes. The quadrat data from these sites will be used to calibrate a vegetation and habitat classification algorithm on selected imagery tiles from the five study areas. The classification algorithm will then be validated against the whole-site imagery, resulting in high resolution vegetation and habitat classification maps that will be used to compare vegetation communities among created and reference marshes. In addition, the created algorithm will have the potential to be applied to other brackish marsh vegetation analyses in the future to benefit post-construction monitoring.

Using a UAV to Monitor Short-term Geomorphological Changes on Crab Bank, a Restored Shorebird Nesting Sanctuary in the Charleston Harbor Estuary

Gary Sundin, South Carolina Department of Natural Resources
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Crab Bank is a dredge spoil island in Charleston Harbor, South Carolina, USA that historically served as an important shorebird nesting sanctuary. The island was subject to erosion over the course of several decades, losing all available high-ground nesting habitat by 2017. To re-create this habitat, the island was re-built in November 2021 using dredged material from the Charleston Harbor. Between December 2021 and September 2022, Crab Bank was mapped seven times with a small, unoccupied aerial vehicle (UAV) to create high-resolution imagery and elevation products. A survey-grade global navigation satellite system (GNSS) was used to improve the accuracy of the mapping efforts. GIS analyses were then used to measure changes in both the shoreline position and the surface elevation of the island during this period. Monitoring flights revealed a high-ground footprint of approximately 15 hectares, with elevations ranging from 1.5 to 2.4 meters above mean higher high water (MHHW). During the monitoring period, elevation changes within the high-ground footprint were generally minor (i.e., < 0.2 meters in all areas). No significant gains or losses in the total area of high-ground were observed. Changes to shoreline morphology were minor and consisted primarily of a re-working of the southwestern border of the island within the intertidal zone. Shorebird nesting on the new habitat was observed throughout the nesting season. These early monitoring efforts showcase short-term geomorphological changes to a newly created shorebird sanctuary in an urban estuary. Preliminary findings demonstrate that the habitat is suitable for shorebird nesting and that the island is an important addition to the limited total footprint of such sanctuaries in coastal South Carolina. Findings further suggest that this habitat is reasonably likely to persist for periods sufficient to promote beneficial population-level impacts to South Carolina shorebirds.

Twenty Years of Data and Counting: NCEI’s Hypoxia Watch as a Tool for Near-Real Time Monitoring of the Gulf of Mexico Hypoxic Event

Courtney Bouchard, NOAA/NCEI
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The Gulf Coast is host to more than half of the nation’s wetland area and the ecosystem services it provides are important economically and socioeconomically to the nation. As many Gulf Coast researchers and resource managers are already familiar, a large low dissolved oxygen (DO) event occurs within the northern Gulf of Mexico. This hypoxic event (DO < 2 mg/l), also known as the “dead zone”, occurs seasonally with varying size every year depending on several environmental factors. When DO levels get below 2 mg/L it can quickly devastate aquatic ecosystems and drive fish, invertebrates, and mammals away affecting the fisheries in the area. There are many working on monitoring and reducing these events. NOAA National Center for Environmental Information (NCEI) Hypoxia Watch’s mission is to monitor DO levels in near-real time with our partners at NOAA Fisheries and the Southeast Area Monitoring and Assessment Program’s (SEAMAP) during the yearly Summer Groundfish Surveys. For this effort, scientists aboard the NOAA Ship Oregon II process the measurements from dissolved oxygen sensors attached to the CTD and send them electronically to NCEI. Then NCEI staff transform the bottom DO measurements into maps that identify areas of hypoxia. New maps are published on the Hypoxia Watch web map viewer regularly while the cruises are underway to help scientists understand the development and progression of the hypoxic event. After 20 years of data collection, the team at Hypoxia Watch is updating the product to include more historical datasets alongside the near-real time monitoring efforts. NCEI staff collaborates with federal agencies, state agencies, and universities, therefore input from our stakeholders is important to make sure that NCEI is getting this data to the public in the most effective way

Full-Capture Devices for Plastic Pellets (Nurdles)

Henry Hunt, Roscoe Moss Company
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Plastic pellets (nurdles) released from plastic production, storage, transportation and manufacturing facilities are light, floatable and can be transported easily by wind, stormwater or other means. These pellets flow into public waters and become damaging to wildlife, fish and aquatic organisms, adversely impacting the environment, most notably in estuarine settings. A passive-screen full-capture device has been employed to capture pellets from industrial facilities and prevent them from being part of the hydrologic cycle. These devices have been used for twenty years for the capture of litter, trash, organics and other debris carried with stormwater across the United States and recent focus on mitigating impacts due to pellets released from industrial sites have identified additional applications for this device. Modifications allow sizing the screen (slot) openings to match the dimensions of target debris (pellets) for full capture of pellets from industrial drains, while minimizing impacts on stormwater flows. The devices are simple, robust and require very low O&M. The poster will illustrate its’ application to coastal environments, especially Americas’ Gulf Coast where the concentration of plastics industries in these regions that drain to the Gulf have experienced recurring impacts. Of course, this device is applicable to all estuarine regions where public waters discharge to oceans and to any sites that discharge to surface waters that drain to coastal areas. The information will be helpful to regulators, plastics-related industries, state and local agencies and organizations and to local communities interested in managing plastic waste within their jurisdiction. Example installations in coastal settings will be presented as will general design criteria for evaluating feasibility and sizing the capture system.

2021 Peconic Estuary Annual Water Quality Report; Are We Meeting Our Goals for a Healthy Estuary?

Sara Cernadas-Martin, Peconic Estuary Partnership
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The Peconic Estuary, the expansive network of bays and waterways located in the east end of Long Island (NY), represents the geographic, ecological and cultural heart of the region. Poor water quality is tied to our actions on land. In the Peconic Estuary, our primary pollution source comes from the movement of water through the ground (groundwater) and over the land surface (stormwater runoff) - this water picks up natural and human-made pollutants, such as fertilizers, pesticides, motor oil, and human and animal waste, and eventually ends up in lakes, rivers, wetlands, and coastal waters. This is known as non-point source pollution, and the two biggest sources in the Peconic Estuary are wastewater from residential on-site septic systems and cesspools, and fertilizers (nutrient pollution). As a National Estuary Program, the Peconic Estuary Partnership (PEP) acts as a bridge at the boundary between science and policy, and ensures that an informed citizenry, along with all other stakeholders, have a voice in the decision-making process. In 2020, PEP developed a Comprehensive Conservation and Management Plan (CCMP) that identifies four long-term goals: Strong Partnerships, Resilient Communities, Clean Water, and a Healthy Ecosystem. This 2021 Peconic Estuary Annual Water Quality Report tracks whether we are meeting our identified water quality targets to achieve our objectives for Peconic Estuary waters. Clean water supports fish, shellfish, and wildlife ecosystem health, provides for safe recreation in and on the water, and seafood that is safe for consumption. This Report will enable PEP to track progress on meeting our CCMP goals for Resilient Communities Prepared for Climate Change, Clean Waters for Ecosystem Health and Safe Recreation, and Healthy Ecosystem with Abundant, Diverse Wildlife over the next decade.

Moving Water to Restore Rivers Wetlands and Estuaries in Central and Southwest Florida

Nicole Iadevaia, Coastal & Heartland National Estuary Partnership (CHNEP)
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National Estuary Programs work regionally and are uniquely positioned as a collaborative of governmental, non-profit, and community partners could step in to fill research gaps, taking the lead on to engage in regional issues and further climate readiness in forward-looking regional research and restoration. The Coastal & Heartland National Estuary Partnership (CHNEP) identified hydrological restoration as a key issue for Central and Southwest Florida given the unique hydrogeology of the region. However, significant challenges remain to reverse damage from development and balance limited water resources between people and natural ecosystems. CHNEP worked to create a number of watershed management plans with the goal to ‘get the water right’, identifying what needs to happen to restore and maintain our water supply, flood protection, water quality and water-dependent resources in the face of existing degradation and depletion, climate change factors, and continued regional growth. In order to build these plans, all available data was gathered and used to develop and refine integrated surface and groundwater hydrological models to simulate the water cycle in the natural environment, identifying how changes to the landscape and environmental conditions will impact where surface and groundwater will move in response. Climate change related impacts such as reductions in freshwater flows, alterations in rainfall patterns, changes to wetland hydroperiods, evapotranspiration and sea level rise were also accounted for. Due to the large scale, complexity, and cost of implementing the plans, most are need a multi-partner, multi-phase, and multi-year approach. The CHNEP supports continued effective coordination between agencies that manage water as well as and local, state, and federal government permitting and capital programs affecting hydrologic flow, water storage, flood control, and water quality. By focusing attention and resources on a landscape-level strategy, restoration projects can yield greater cost-benefits.

Ida's Lasting Impact: The Barataria Preserve's Immobilized Salinity

Aaron Gondran, National Park Service
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The Barataria Preserve of Jean Lafitte National Historical Park and Preserve protects 26,000 acres of freshwater deltaic wetlands in the Mississippi River delta’s Barataria Basin, which are among the most biologically productive ecosystems in North America. Hurricane Ida’s late-August landfall completely submerged the Preserve in saltwater. High concentrations of salt are toxic to native vegetation, can alter ecosystem properties, and can lead to a decline in biodiversity. Several months after Ida we continue to observe elevated salinity levels across the Barataria Preserve landscape. Our water quality measurements show abnormally high salinity compared to previous post-storm surge periods. At most sites, our data illustrate a drastic increase in salinity right after the storm, an ephemeral decrease after a September rain event, and increasing salinity thereafter well into the 2022 growing season. We evaluate data from our monthly discrete sampling at 14 near-trail waterway channel and wetland sites that capture the Preserve’s topographic and hydrologic variation, and we reference others’ observations collected in and adjacent to the Preserve. The La Nina weather pattern may be responsible for the high salinity of the Preserve by causing dry conditions from a low precipitation rate. In this presentation we explore how La Nina has shaped the patterns of post-Ida salinity across the Preserve into the next growing season. Monitoring water quality attributes across the Preserve over time helps park managers track changing conditions and better understand linked outcomes for biota and ecosystems. These post-Ida La Nina phase observations offer insight into how this freshwater wetland landscape may change under the predicted increased frequency of strong tropical storms, some of which will be followed by La Nina phases of global circulation.

Effects of Drought, Pulsed Freshwater Inflows and Nutrients Imported from the Gulf of Mexico on Primary Production and Water Quality in the Mission-Aransas Estuary

Edward Buskey, University of Texas Marine Science Institute
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The Mission-Aransas Estuary is in an arid region of South Texas with limited rainfall. The low freshwater inflows can be occasionally replaced with short duration, large freshwater pulses due to storm events that can deliver up to half of annual inputs of new nutrients from the rivers. Low freshwater input, small tidal range and a nearly continuous barrier island separating the estuary from the Gulf of Mexico result in a typical water replacement time of about one year. Five monitoring stations collect water quality data at 15-minute intervals, and nutrient and plankton samples have been collected monthly over the past 14 years. These data reveal the impacts of extended periods of drought punctuated by major inflows of freshwater to the estuary on nutrient concentrations, phytoplankton biomass, primary production and net ecosystem metabolism. Short term changes in nutrient concentration and phytoplankton biomass can be seen in response to intense inflow events, but seasonal patterns of primary production are similar during periods of drought and high salinities compared to periods following higher freshwater inflows, nutrient loading and lower salinities. There is a shift to a net heterotrophic system following major inflow events that import large amounts of terrestrial organic matter, compared to a more balanced system during periods of low freshwater inflow. Nutrient concentrations in near shore waters along the Texas Coast are typically higher than those found within the Mission-Aransas Estuary due to high nutrient inputs from the Mississippi River. Sampling at 2-hour intervals in the channel between the Gulf of Mexico and the estuary show that on high tides nutrients are imported from the Gulf into the estuary. The estuary maintains high productivity with efficient nutrient recycling in this shallow, warm water system supplemented by nutrients from near shore Gulf waters and episodic inputs of nutrients from freshwater inflows.

Ribbed Mussels Enhance Pelagic-To-Benthic Transports of Marine-Derived Nitrogen through Faunal Engineering

Sydney Williams, University of Florida
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The increasingly pervasive issue of coastal eutrophication has sparked widespread interest in leveraging bivalves as bioremediation tools against excessive nitrogen loading in estuaries. Ribbed mussels (Geukensia demissa) facilitate pelagic-to-benthic transport of organic N through suspension-feeding and biodeposition and subsequently enhance N availability for uptake, burial, and removal in salt marsh systems. Source tracing of this organic N may be informative and applicable to nutrient management decisions but has received little attention. Here, we quantified the effect of mussels on the composition (marsh- and marine-derived sources) and biomass of organic N conveyed from the overlying tide water to the sediment surface in a Georgia salt marsh. We measured C and N stable isotope signatures and N biomass of particulate organic matter (POM) available in the water column, actively conveyed by mussels, and passively transported in the absence of mussels (smooth cordgrass only) during a spring high tide. By building our stable isotope data into Bayesian mixing model frameworks (MixSIAR), we found that, when compared to material transported in cordgrass only areas, mussel biodeposits had higher proportions of marine-derived (pelagic phytoplankton) OM and were more similar to water column POM. We then multiplied MixSIAR source proportions by N biomass values and determined that mussel presence enhanced the pelagic-to-benthic transport of both marine-derived and marsh-derived (cordgrass detritus and benthic microalgae) organic N by over an order of magnitude. Our findings demonstrate that this faunal engineer plays a significant role in both the importation and recycling of organic N in salt marsh systems and deserves more consideration and inclusion in nutrient management efforts.

Developing Techniques for Long Term Chlorophyll a Monitoring in Estuarine Systems

Emalee Swisshelm, University of New Orleans
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Chlorophyll a, an indicator of eutrophication and the presence of potentially harmful algal blooms, can provide key insight into the health of a water system and provide information on best management practices. The measurement of chlorophyll a through pigment extraction methods is a key component of the National Estuarine Research Reserve’s (NERR) System-Wide Monitoring Program. However, the collection and analytical process of this method can be time consuming and the ability to collect data at 15-minute intervals using a data sonde in the field would provide key insights into the primary production of these dynamic environments. Sensor technology has been developed, but it is important to consider environmental factors, such as temperature, turbidity, and fluorescent dissolved organic matter, as they can highly influence the readings when measuring in situ chlorophyll a fluorescence. NERR staff nationwide are developing empirical relationships for individual long-term monitoring stations so that in situ chlorophyll data can be interpreted in the context of historical and concurrent extracted chlorophyll data. During June 2022, for a National Science Foundation Research Experience for Undergraduates internship, extraction and in situ methods were compared at two environmentally variable stations in the Guana Tolomato Matanzas NERR. A positive relationship between extracted and in situ chlorophyll measurements was present at both stations, but each relationship was impacted by different environmental factors. Due to the short duration of this study, more comparisons are needed to capture natural ranges of rainfall, organic matter, and temperature variations in the estuary.

Do Prescribed Burns Yield Enhanced Carbon Storage in Salt Marshes? A Comparative Assessment in Delaware Salt Marshes with Varied Burn Histories

Christopher Kelly, School of Marine Science and Policy, College of Earth, Ocean, and Environment, University of Delaware
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Prescribed burns are a common management practice within the state of Delaware as well as across the US. In salt marsh environments, these burns are employed to remove invasive Phragmites australis and restore native vegetation. A byproduct of these burns is a layer of biochar that remains in the sediment. This layer of biochar, or black carbon, is presumed to be refractory, staying within the sediment on decadal to millennial timescales. Biochars have also been shown to act as a sorbent retaining nutrients, pollutants, and organic molecules. It follows that an important question with regard to prescribed burns used to manage salt marshes is whether these biochar inputs impart biogeochemical ecosystem services in the form of blue carbon and nutrient storage in soils with benefits for the removal of carbon dioxide from the atmosphere and reduced nutrient loads to adjacent water bodies. With this project we address this question by examining 3 marsh tracts in Delaware with varying burn histories: Rocks Tract (no recent burn, burn planned for 2022), Roberts Farm (burned repeatedly over the last 5 years), and St Jones Reserve (no burn history or plans). Rocks Tract and Roberts Farm are located adjacent to each other and experience similar hydrology and environmental conditions making their burn histories the primary variable. The St Jones Reserve represents a nearby control site with no burn history. Ten 15 cm cores were collected from each site then sectioned into three, 5 cm sections and analyzed for carbon, black carbon, and nitrogen contents. The carbon, black carbon, and nitrogen compositions will be compared across areas of differing burn history taking marsh spatial dynamics into account. Increased carbon, black carbon, and nitrogen in burned versus unburned marsh regions are expected to provide evidence for biogeochemical ecosystem services from prescribed burns.

Air-Water Gas Exchange Over Temperate Seagrass Meadows

Kayleigh Granville, University of Virginia
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Blue carbon ecosystems such as seagrass meadows are widely regarded as carbon sinks. However, carbon storage in these ecosystems can be partially offset by emissions of greenhouse gases such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). Although the importance of measuring these fluxes is widely recognized, there is a lack of reliable flux data, especially in seagrass meadows. Existing fluxes are often uncertain due to internal site variability, low sampling frequencies, and methodological limitations. More local and regional CO2, CH4, and N2O flux measurements are needed to constrain variability and identify diurnal and seasonal patterns. In this study, we derived mid-summer greenhouse gas fluxes over a temperate seagrass meadow (South Bay, Virginia Coast Reserve Long-Term Ecological Research site). To address potential methodological limitations, we measured wind speed, a variable commonly used to estimate air-water gas fluxes, on site. We compared on-site wind speeds to wind data collected at a regional NOAA station. Differences between on-site wind speed and regional wind speed show the importance of collecting in situ data. The time series of CO2 and CH4 fluxes derived from the on-site data reveals diurnal patterns and the effect of a storm event. Overall, the high temporal resolution applied in this study captured the internal variability at our site, and demonstrates the importance of measuring greenhouse gas fluxes in blue carbon ecosystems on a local scale.

Louisiana Coastwide Avian Restoration, Monitoring and Adaptive Management

Jon Wiebe, Louisiana Department of Wildlife and Fisheries
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Significant avian impacts were documented in association with the Deepwater Horizon oil spill. The State of Louisiana in concert with natural resource partners (local, regional, national) continues to design and implement representative restoration projects that are intended to directly benefit these impacted species. In tandem, significant efforts continue towards informing future project design and construction processes, individual project and coastwide performance monitoring as well as adaptive management.

Mitigating the Effects of a Large River Diversion on Bottlenose Dolphins (Tursiops Truncatus) using Ridge Restoration: Barataria Basin, Louisiana, USA

Denise Reed, University of New Orleans
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Coastal land loss in Louisiana is driven by natural and anthropogenic factors including the disconnection of coastal wetlands from the riverine inputs of sediment, nutrient, and freshwater.. This is particularly true for Barataria Basin where the estuary has been isolated from the Mississippi River by a flood protection levee system. A proposed diversion is designed to deliver sediment and freshwater to the basin to ameliorate land loss, which will also alter the salinity distribution and impact the local population of common bottlenose dolphins (Tursiops truncatus). To potentially mitigate these effects, this study examined the efficacy of ridge restoration to maintain areas of suitable habitat for these marine mammals. This study uses a three-dimensional Delft3D model to perform detailed salinity analysis for Barataria Bay. The model is used to assess the benefits of various ridge configurations to create or improve suitable salinities for the dolphins in conjunction with diversion operation. The analysis was performed with wet and average Mississippi River hydrographs and for conditions representing 10 and 30 years into the future to capture the effects of sea level rise and subsidence. The analysis shows that certain ridge alignments could potentially provide a suitable habitat for bottlenose dolphins without detracting from the primary land-building objective of the sediment diversions, though further analysis is needed.

Implementation and Preliminary Monitoring of the Truro-Onslow Dyke Realignment and Tidal Wetland Restoration Project.

Jennie Graham, CBWES Inc.
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Coastal ecosystems are shaped by ecomorphodynamic processes that help them to protect the mainland against erosion and flooding while providing habitat for species of conservation and/or commercial value. However, climate change and habitat loss threaten these ecosystems and their functionality. “Building with Nature” solutions, including sand engines and marsh sills with living shorelines, can restore coastal ecosystems, but neither has been trialed in areas subject to harsh winter conditions. A Piping Plover habitat compensation project currently underway at a barrier spit near Shippagan, New Brunswick is piloting both techniques in Atlantic Canada, with the intent of restoring degraded sandy beach, sand dune, and salt marsh habitats. My research seeks to address knowledge gaps surrounding a) whether these restoration techniques can be used in cold climate regions and their ecomorphodynamic and ecological impacts, and b) whether habitats restored using these techniques are ecologically comparable to their natural counterparts. A longitudinal study will analyse how restored habitats change seasonally and over time, while two comparative studies will assess how the restored beach-dune system and the restored marsh compare with nearby naturally-occurring ones. Geospatial, environmental, and ecological data, collected seasonally, will be examined through an ecological integrity lens: Analyses of biodiversity, geomorphology, and food web dynamics will be used to assess the composition, structure, and function, respectively, of the restored habitats. These results will improve our understanding of how restoration methods influence barrier spit ecosystems in cold climates, and how cold climates influence restoration outcomes.

Understanding the Effects of Managed Realignment on Ecosystem Recovery and Nature-Based Climate Adaptation Functions of Tidal Wetlands in the Bay of Fundy, Canada

Kailey Nichols, Saint Mary's University & CBWES Inc.
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Traditional forms of coastal defense infrastructure are not going to be sufficient to combat the challenges that arise from climate change. As society continues to recognize that the traditional “hold-the-line” approach for coastal protection is no longer a viable option, managed (dyke) realignment (MR) has been shown to render a more dynamic solution to reduce coastal risks including storm surges, erosion, and flooding events, while also creating or improving ecosystem services. This research aims to determine the impact of incrementally increasing MR schemes on estuarine morphodynamics and restoration trajectories by assessing key parameters such as hydrology, sediment, and vegetation in the Converse Marsh, located on the Chignecto Isthmus in Nova Scotia, Canada. Specifically, this research will assess the influence of sediment deposition and hydrodynamics on vegetation colonization on different spatial and temporal scales using UAV surveys, geomatics, and field surveys. Although realignment techniques are relatively well understood, the response of our hypertidal coastal systems within the Bay of Fundy to MR schemes are underrepresented in the literature. By studying the efficacy of nature-based solutions and the trajectory of these approaches, namely managed realignment, there is a greater capacity to limit current and future risks associated with climate change and to implement these innovative designs on a larger scale.

Understanding Parameters for Site Characterization and their Influence on Restoration Trajectory in Tidal Marshes in Nova Scotia, Canada

Kayla Williams, Saint Mary's University & CBWES Inc.
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Low-lying coastal ecosystems, such as tidal wetlands, are vulnerable to degradation or loss due to climate change and anthropogenic influences. Accelerated changes in vegetation distribution and pattern, vertical accretion, and erosion along the marsh edge have called into question the sustainability of these ecosystems into the future. There are few remaining untouched, natural tidal marshes in Nova Scotia therefore, ecosystem restoration has been a popular avenue for rehabilitating vulnerable marshes. Recent studies have attempted to characterize tidal marshes based on their conditions from measured variables rather than simply ‘restored’ versus ‘natural’ tidal marshes. Further, there is a research gap surrounding the trajectory of restoring tidal marshes in Nova Scotia and whether site pre-conditions impact the restoration trajectory. We are investigating the characterization and trajectory of restoring and natural tidal marshes within Nova Scotia. We are assessing site similarities and differences based on abiotic variables, taking into consideration geomorphology, hydrology, sedimentation, elevation, vegetation, and carbon sequestration. We are exploring trajectory following characterization of natural and restoring marshes, considering site pre-conditions for restored marshes. We intend to analyze previously collected data in addition to re-measuring parameters between 2021-2022 as a present day baseline. Parameters to be measured include Rod Surface Elevation Tables (RSETs), marker horizons (MH), sediment cores, and vegetation surveys. Our characterization and restoration trajectory data for Nova Scotia will allow for a better understanding of how each variable impacts marsh health and contribute to the improvement of restoration techniques and post-restoration monitoring activities.

Making Room for Wetlands: Implementation of Managed Realignment & Salt Marsh Restoration to Enhance Resilience of Dykeland Communities to Climate Change in the Bay of Fundy, Canada

Tony Bowron, CBWES Inc.
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Globally, the practice of re-introducing, where feasible, tidal flow to former agricultural dykelands and the restoration of tidal wetland habitat, has been identified as a viable adaptation method to current and future hazards associated with climate change. While previous efforts to restore coastal wetlands in Atlantic Canada focused primarily on the restoration of resilient and self-sufficient habitats, the increasingly tangible impacts of climate change combined with changing economic landscapes, regulations, and land use practices have shifted and broadened the objectives of these projects. With limited resources available, guidance is required to determine where and how dykes should be re-aligned to optimize ecosystem services, maximize adaptation benefits, minimize economic costs and maintain fertile agricultural land and social, cultural and historic activities. The Making Room for Wetlands project is building resilience to climate change impacts of dykelands in the Bay of Fundy, Canada by demonstrating the successful of implementation of managed dyke realignment and the restoration of salt marsh habitat. Demonstration sites were selected in collaboration with the Provincial body responsible for dyke maintenance, after a comprehensive dyke vulnerability assessment and builds upon over two decades of collaboration and experience in tidal wetland restoration. The design, implementation and monitored of the restoration trajectory of the sites will be presented. Focus will be on the influence of sediment supply, tidal range, restoration design and seasonal timing of re-introduction of tidal flow on the rate of vegetation recolonization and implications for long term resilience.

Building Elevation in Mangrove Communities: Use of Regional Sediment Management to Increase Coastal Wetland Resilience to Sea Level Rise.

Gina Paduano Ralph, U.S. Army Corps of Engineers
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Sea-level rise (SLR) is expected to affect natural and urban areas by shifting habitats and inundating coastal developments in South Florida. Given this challenge of SLR, building resiliency within South Florida’s natural communities is imperative, not only to protect an abundance of fish and wildlife species, including important recreational and commercial fisheries, but also as a means of protecting the built environment from adverse effects associated with coastal storm surge and saltwater intrusion. For coastal wetlands to exist into the future, soil accretion must match or outpace SLR. Beneficial uses of dredged material such as thin layer placement (TLP) will build landscape resiliency by building soil elevation and improve soil aeration in the root zone. This proof of concept physical model will evaluate the ability of TLP to increase elevation and enhance net primary productivity within coastal wetlands of Miami-Dade County, Florida most vulnerable to SLR. Varying depths of beneficial-use materials will be placed at selected sites to identify 1) whether TLP is a viable option to build elevation to increase the adaptive capacity of coastal wetlands to SLR, and 2) whether TLP can also promote internal mechanisms of peat accretion (i.e., root growth and carbon sequestration) within coastal wetlands, including mangrove communities. The results of this proposal will also inform and direct management measure development for the ongoing U.S. Army Corps of Engineers Biscayne Bay Southeastern Everglades Restoration Project, the only coastal component of the Comprehensive Everglades Restoration Plan. However, results from this proposal are applicable to areas throughout the Gulf, Atlantic, and Pacific Coasts of the United States where direct preservation, enhancement, and restoration of mangrove and other vegetative communities, will build coastal resiliency, reduce storm surge damage, and create habitat for a variety of fish and wildlife species.

Foundational Dune Grass Growth Is Enhanced by Atlantic Ghost Crabs (Ocypode Quadrata)

Joseph Morton, University of Florida
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Coastal dune ecosystems and the myriad of ecosystem services they provide are increasingly threatened by anthropogenic stressors. The loss of dunes has underscored the importance of rapid and effective dune restoration to enhance coastal resilience. Harnessing positive species interactions that enhance vegetative growth and dune accretion is one way to enhance dune restoration success at little to no added cost. Previous research has indicated the importance of inter- and intraspecific facilitation between dune plants, however, comparatively little research has focused on facilitation by animals in coastal dunes. Here, we examined whether a common dune bioturbator, the Atlantic ghost crab (Ocypode Quadrata), could facilitate the growth of coastal dune vegetation.A field manipulation of ghost crab abundance on a restored dune showed that aboveground production of outplanted sea oats (Uniola paniculata) increased with increasing crab burrow area. Additionally, a survey of 8 coastal dune sites in the southeastern US revealed positive correlations between burrow area and the heights of adjacent dune grasses. Taken together, these results underscore the importance of considering positive species interactions in dune restoration praxis.

Storm Influence on Soil Properties of a Saltmarsh in Barataria Basin, LA

Matthew Parker, Louisiana State University
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The frequency of major storms along Louisiana’s coast will rise with a changing climate. Saltmarshes that constitute these areas possess a mixture of organic and inorganic soil layers that help combat erosion during storm influence. Inundation from major storms could potentially alter soil composition which will affect the future resiliency of these saltmarshes. This study aims to compare the soil properties of the edge and interior of a marsh that experience different tidal inundations. A saltmarsh at the Barataria Basin, LA, was selected due to its proximity to a Louisiana’s Coastwide Reference Monitoring System site where data on vegetation, hydrology, elevation change have been collected for the last 10 years. Three 90 cm sediment cores each were collected at both the edge and interior of the saltmarsh in summer 2022. Bulk density, organic matter, and sediment accretion rate will be analyzed using loss on ignition and 137Cs gamma dating. Our preliminary results showed that shallower layers (<50 cm) had higher bulk density and lower organic matter when compared with deeper layers. A spike in bulk density at the top of the soil profile shows influence from a recent major hurricane, Ida which made landfall on August 29, 2021. Data collected for this study could provide valuable information for coastal restoration and management projects along the Gulf Coast.

Belle Isle Marsh: Assessing the Climate Vulnerability Potential Adaptation of Boston's Largest Salt Marsh

Grace Medley, Woods Hole Group
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Belle Isle Marsh, designated an Area of Critical Environmental Concern, is the largest remaining saltmarsh in Boston Harbor. It serves as buffer against coastal storms, critical habitat for nesting birds, and recreational space for surrounding communities. Adjacent to three major cities, the marsh is under a series of stressors, ranging from anthropogenic influence to rise in local sea level and coastal storms. Wetland filling, berm construction, mosquito ditching, stormwater outfalls, coastal squeeze, and other factors are impacting the natural function of the marsh. These stressors have resulted in marsh degradation over time. The goal of this project is to protect and enhance the natural resources now and into the future, and combines an ecosystem management approach with coastal community flood resiliency. The EFDC hydrodynamic model was configured for Belle Isle Marsh and run for a series of daily and future SLR conditions, using indicators such as temperature, salinity, and residence time to assess the health of the saltmarsh. The SLAMM model was run to describe changes to the marsh habitat from present day to 2100. The results found Belle Isle Marsh habitat to be projected to convert to greater open water area, with losses of high marsh habitat. Under high sea level rise scenarios, the marsh is anticipated to predominantly convert to mudflat, while developed areas prohibit inland migration of marsh habitat. Through revealing which habitats are most vulnerable, the team established restoration values, goals, and alternatives, to enhance marsh health and bring co-benefits to surrounding communities. Adaptive management scenarios were selected to model present and future conditions, including enhanced tidal exchange and drainage, water level control measures, and thin layer deposition. Adaptation recommendations are compiled into a management plan, merging the science, and needs of stakeholders and residents to inform long-term management of this critical habitat.

Design of Marsh Rim Buffer at Black Bay in St. Bernard Parish

Matt Salmon, Freese and Nichols
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Black Bay Ridge is a project led by St. Bernard Parish Government. The Project has been submitted for inclusion in the 2023 Louisiana Coastal Master Plan and received positive feedback from Louisiana Coastal Protection and Restoration Authority. It is uniquely located at the southern edge of St. Bernard Parish between Chandeleur Islands and the future Mid-Breton Diversion. The location was strategically selected to provide another layer of risk reduction for a Parish coastal system that provides multiple lines of storm surge defense. The Project will provide immediate and much needed protection for southern St. Bernard and Plaquemines Parish by absorbing wind and wave energy from the Gulf of Mexico and serving as a barrier to prevent further saltwater intrusion into the area. The Breton Sound Basin has experienced substantial land loss because of factors such as hurricanes and the loss of oyster reefs. This wetland area serves an important role as a buffer between storm surge in the Gulf and populated areas of St. Bernard Parish and New Orleans. Additionally, the coastal marshes of St. Bernard Parish and Plaquemines Parish provide critical habitat for wildlife and enormous financial benefits to the region in the form of recreational and commercial fisheries. The Project will be approximately 8 miles long and create 1,050 acres of back barrier marsh, 105 acres of upland ridge, and 631 acres of ridge foundation. Project design considerations include construction of a marsh and ridge on soft sediments, a dredge delivery pipeline of approximately 20 miles, and circulation and morphology modeling. Modeling analyzed Project effects on the area’s salinity regime, potential wave attenuation benefits, and suitability to enhance oyster habitat.

Poplar Island and Sabine National Wildlife Refuge as Case Studies for Marsh Restoration Trajectories

Safra Altman, USACE Engineer Research and Development Center
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The loss of coastal wetlands due to climate change, changes in sediment supply due to human activity, among other factors has led to a surge of wetland creation projects utilizing dredged material. Understanding the restoration trajectories of these sites can inform future restoration design, monitoring and adaptive management plans, and determinations of restoration success. We are developing trajectories for two separate restoration areas: Poplar Island in the Chesapeake Bay, Maryland and The Sabine National Wildlife Refuge (NWR) located on the Calcasieu Pass in Louisiana. Both projects utilized dredge material as the source of sediment for site development, though they employed different restoration approaches, monitoring regimes, and adaptive management. For each site, we are assessing a number of parameters to understand development across the chronosequence of individual restored marsh units, including vegetation patterns and other marsh characteristics, selected based on scope, resources, and accessibility. Our case studies focus on sediment chemistry, vegetation, and bird population monitoring data in Poplar Island, and vegetation, soil shear strength, and physical, biogeochemical, and microbial properties at Sabine NWR. We compare and contrast different methods of restoration and monitoring to facilitate efficient determinations of success, and likely trajectories of multiple marsh parameters. These trajectories may also offer context to interpret the relevance of stochastic perturbations in marsh restoration development, and the necessity to intervene to meet restoration success criteria.

Phragmites Australis (Common Reed) Fitness and Morphology Along a Salinity Gradient in a Long Term Restoration Project

Alizia Rhodes, Texas A&M University at Galveston
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Anthropogenic changes to freshwater inflow into estuarine environments may have detrimental consequences, as changing salinity regimes may cause some species to proliferate at the expense of others. One such species of management concern is Phragmites australis (common reed) in the Anahuac National Wildlife Refuge (ANWR, Texas, USA). This grass can potentially invade lower salinity portions of estuaries following disturbances such as hydrological alteration or nutrient input. In the ANWR, the recent (2019) closure of a tidal inlet (Rollover Pass) as part of a hydrological restoration project results in decreased tidal input and lowered salinity in the ANWR. As a result, Phragmites management may become more challenging within the refuge. To assess the potential for Phragmites proliferation and thus inform future management decisions, a field survey was conducted at three sites along a salinity gradient within the ANWR. Soil salinity was three times higher at the two downstream sites than at the site furthest upstream. Phragmites stems were 20% taller at the site furthest upstream where soil salinity was lowest. Phragmites stem density and leaf chlorophyll a content were similar at all sites. Although there is some indication that Phragmites may have higher fitness at the lowest salinity site, stands of this species persisted at all three sites. In addition, soil salinities remained high at downstream sites for more than two years following the hydrological restoration project. These results suggest that salinity levels may prevent rapid near-term Phragmites proliferation within the reserve. This may have real-world implications for future wetland restoration and management.

Evaluation of Louisiana Ecotypes of Saltgrass for Selection and Use in Salt Marshes of the Coastal Zone of Louisiana

Garret Thomassie, USDA - Natural Resources Conservation Service
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Saltgrass (Distichlis spicata) is a mat-forming, strongly rhizomatous perennial grass that prefers moist, saline soils, and is often found in sandy, alkaline locations. It is important in salt marshes as nesting habitat for birds, fish and larvae of many species of marine invertebrate animals. Saltgrass persists in saline inundated ecosystems including marshes along the coasts of the Atlantic and Pacific Oceans, and the Gulf of Mexico. It is also one of the more drought-tolerant marsh grasses. Saltgrass is a highly desired plant for coastal restoration projects and is frequently requested for re-vegetation contracts by conservation partners, including those representing federal, state and parish governments and private consultants. However, there is a lack of quality tested plants of this species, especially in sufficient numbers for growers to obtain for commercial production. The USDA-Natural Resources Conservation Service Golden Meadow Plant Materials Center (PMC), Galliano, LA has evaluated 25 accessions of saltgrass collected across coastal Louisiana. Objective of this effort was to identify accessions exhibiting vigorous, drought and flood tolerance, active seed germination, with exceptional spread. Accessions were planted in an initial evaluation in a randomized complete block with three replications in a field where water levels can be managed and manipulated to simulate tidal flux, as in the coastal marsh. Ten of the 25 accessions exhibited superior growth characteristics and worthy of further evaluation and selection. Evaluations of the 10 promising accessions will continue in 2022 by comparing their performance and adaptation at multiple sites in South Louisiana. The PMC plans to release a saltgrass for commercial production for coastal restoration projects in Louisiana coastal parishes.

Restoring Louisiana Coastal Marsh Habitat through Sustainable Sediment Beneficial Use Practices

Andrew McQueen, U.S. Army Engineer Research and Development Center
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Coastal Louisiana (USA) continues to sustain immense land and habitat losses due to subsidence, sea-level rise, and storm events. Approximately 65 million cubic meters (85 million cubic yards) of sediment is dredged annually from Gulf Coast Federal navigation channels to maintain safe waterway passage. The beneficial use of these sediments continues to increase and now this sediment is recognized as a critical resource in large-scale (estimated multi-billion dollar) ecosystem restoration efforts to mitigate land and habitat losses along the U.S. Gulf coast. Yet, documenting the restoration benefits of such projects where dredged sediment is the primary resource is lacking, which limits the potential for future applications. Therefore, this study documents the progress to restore marsh habitat and the resultant benefits in West Bay, Louisiana and investigates how the restoration practices align with principles of the U.S. Army Corps of Engineers (USACE) Engineering with Nature® (EWN®) and UN Sustainable Development Goals (SDGs). Restoration performance was assessed through remotely sensed methods using data spanning approximately 70 years. West Bay, a 4,964-hectare sub-delta adjacent to the Mississippi River, typifies risks of coastal land loss that also threatens the integrity of the adjacent Federal navigation channel. To help restore coastal marsh habitat on a large spatial and temporal scale, the USACE constructed an uncontrolled diversionary channel from the Mississippi River and with subsequent direct and strategic placement of dredged sediment. To date, placement of dredged sediment in the bay facilitated the creation of over 800 hectares of new land in the formerly open waters of West Bay. The West Bay restoration project is a pertinent example of how principles of the EWN initiative deliver nature-based engineering solutions to achieve economic, environmental, and social benefits through collaborative processes, and how the project meaningfully integrates UN SDGs designed to achieve a better and more sustainable future.

Coastal Plain Stream, Floodplain and Wetland Restoration Using Wood Structures Harvested from the Project Site

Joe Berg, Biohabitats
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Wood is a natural renewable resource and has been a common feature in stream stability across North America prior to extirpation of beaver, European colonization, and removal of wood from streams under the mistaken auspices of creating fish passage and mitigating flooding risks. Adding wood to riffle features to improve their habitat quality, using buried wood as bank stabilization and habitat improvement features, using rootwads to attenuate velocities and improve bank cover are all highly valued applications of wood in stream restoration. The use of wood in stream restoration structures is a logical refinement of stream restoration techniques. Building wood and earth plugs in incised, over-widened, and disconnected stream channels re-establishes lateral floodplain reconnection without extensive grading, creates deeper stream flow to support better aquatic life habitat and hyporheic connectivity, and reduces sediment and nutrient loading. In addition, this approach is regenerative and sustainable in a forested landscape. Wood production rates are higher than decomposition rates. Floodplain reconnection reduces in-stream shears and supports accumulation of wood and leaf material. The restored groundwater supports riparian and floodplain wetland community development and helps maintain stream temperature and flow during dry periods. Wood also creates a much more structurally complex habitat. A project totaling more than 20,000-lf that used engineered wood structures in combination with an understanding of natural stream and floodplain processes and functions to deliver significant functional uplift will be presented as a model for Gulf Coast stream restoration. The design approach, the regulatory experience, and the results of groundwater monitoring will be discussed. The goal is to stimulate more projects of this type by helping the design and construction community to build capacity for this type of truly sustainable ecological restoration.

Examining the impacts of coastal development and mangrove coverage on oyster abundances in Mosquito Lagoon, FL

Emily Suchonic, University of Central Florida
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Historically, below-freezing winter air temperatures have limited mangrove expansion in sub-tropical and temperate estuaries. However, as winters have grown warmer within the past century, red (Rhizophora mangle) and black (Avicennia germinans) mangroves have begun expanding poleward into temperate salt marshes and increasing in abundance in sub-tropical estuaries where oyster reefs occur. Previous research from McClenachan et al. (2021) found a 103% increase in mangroves on oyster reefs in Mosquito Lagoon, FL, potentially causing a decline in oyster acreage. However, eastern oysters (Crassostrea virginica) can attach to mangrove aerial roots, which suggests increased mangrove area could provide additional substrate for oyster settlement. Another mechanism influencing oyster success is increasing available hard substrate for recruitment through changes in land use and shoreline stabilization. Using high-resolution imagery and Summer 2022 field surveys, this study aims to determine how mangrove encroachment affects oyster abundances. From the imagery, random sampling points were generated in three regions (North, Central, South) (n=216 points) for each of four site types: 1) mangroves + oysters on oyster reefs, 2) mangroves + oysters seaward of stabilized shorelines, 3) oysters on mangrove islands, and 4) mangroves + oysters along unrestored shorelines. Monitoring metrics included densities of live and dead oysters by substrate type (mangrove roots, stabilization materials, and reef oysters) and live oyster shell lengths. Preliminary results showed northern sites with the largest mean shell lengths (± S.D.) and oyster percent live were mangroves + oysters on oyster reefs (28.6 ± 21.7 mm; 35% live) and mangroves + oysters along stabilized-shorelines (23.2 ± 16.2 mm; 64% live). Additionally, stabilization materials had the tallest mean live (61.8 ± 117.7 mm) and dead oyster attachment heights (58.0 ± 107.1 mm) (± S.D.). Going forward, we will digitize mangrove abundance changes during recent decades and continue collecting field data on oyster abundance on mangroves.

Piloting Seagrass Restoration in Mosquito Lagoon, FL

Gabriel Benson, University of Central Florida
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Halodule wrightii (Hw) is the most abundant species of seagrass in Mosquito Lagoon FL, the northernmost basin of the Indian River Lagoon system. Between 2009 and 2019, seagrass coverage in southern Mosquito Lagoon declined by 97% representing a substantial ecosystem disturbance. To inform future restoration efforts, our goals were to assess efficacy of planting methods, model seagrass suitability, and establish a nursery in which fragments can be grown before out-planting. Suitability modeling was conducted using ArcGIS Pro and focused on identifying the best shorelines for planting. A recirculating pilot nursery was established to help determine which fragments are most suitable for collection, as well as gain insights as to how Hw grows in a closed system. A field study compared the success of field-collected Hw fragments (all with 5 shoots) attached with floral wire to biodegradable BESE™ elements, garden staples, and burlap mats. Treatments were deployed in June 2022 across 5 shorelines. At each site four, 1m¬2 plots were established and randomly assigned as a planting treatment or a control. At the time of planting every plot was bare of seagrass. Monitoring was conducted bi-weekly through September and will continue monthly through December 2022. During the study period, seagrass coverage increased dramatically throughout the system. Although planting success varied greatly between sites, after 9 weeks, the shoot density in staple plots was 287% greater than in control plots. Preliminary analysis suggests the staple plots were the only planting treatment with significantly more seagrass than control plots. Hw fragments survived in the pilot nursery and new growth was observed. Shoreline slope, and low wave action were found to be the best predictors of site suitability. The findings from this study will guide larger-scale seagrass planting efforts during the spring of 2023.

Unravelling Feedbacks Preventing Seagrass Colonization

Beatriz Marin-Diaz, University of Florida
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Coastal ecosystems can provide protection to critical national infrastructure by preventing coastal erosion and attenuating waves. Tyndall Airforce Base, which is located in Saint Andrew Bay, FL, is surrounded by seagrass meadows that are vulnerable to hurricane damage and loss of shoreline protection services. During summer 2022 we assessed the state of the seagrass inside and outside the Bay and we found a large decline in the Gulf side, directly exposed to the hurricane Michael in 2018, whereas seagrass on the bay side appears to be stable during the same time period. We are currently examining patterns of seagrass establishment, sediment movement, and bioturbators to evaluate bare areas that are suitable for restoration. Initial results from a field experiment show that a combination of bioturbators and sediment movement may be keeping some areas bare. These ecological processes could be reinforcing bare patches and potentially counteracting the long term success of restoration activities.

Harnessing Natural Succession to Enhance Coastal Dune Restoration

Hallie Fischman, University of Florida
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Coastal dune restoration efforts have been escalating globally as a way to protect valuable infrastructure from rising seas and increasing storms. However, restored dunes vary widely in their ability to establish resilient systems and have notoriously high failure rates. Traditional dune restoration involves the planting of a single dominant grass species across the entire dune face, disregarding the high native diversity in these systems, stressful conditions that are common after restoration, and natural recovery pathways. Here, we evaluate if dune restoration outcomes can be improved by planting early successional pioneer species. We test if the facilitation model of succession, where pioneer species enhance the establishment of climax species by ameliorating stressors, applies to sand dunes and if this natural recovery pathway can be harnessed to increase dune restoration success. Field surveys of Southeastern US dunes suggest that Panicum amarum is commonly found in disturbed areas, suggesting it acts as an early successional species. A planting experiment revealed that stem production of the dominant dune grass Uniola paniculata is enhanced by 37% over one growing season in the presence of Panicum, while Panicum growth is suppressed by 40% in the presence of Uniola, confirming their respective roles as pioneer and climax species. An additional field experiment evaluated the optimal Panicum density that maximizes Uniola growth. These results suggest that planting early successional species in addition to or prior to planting climax species can increase the growth rate of dune building grasses, which is critical for establishing resilient, high-functioning dunes.

Comparing Spotted Gar Reproductive Potential and Body Condition in Connected and Disconnected Floodplains

Emily Ott, Nicholls State University
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To mitigate flood damage, Louisiana has implemented extensive hydrological modifications that have disconnected floodplains such as the upper Barataria Estuary (UBE) from the mainstem of the Mississippi River. Historically, floodplains that were connected to the mainstem of the River were inundated by an annual flood pulse and were highly productive. Organisms in the disconnected UBE floodplain experience lower food availability, reduced vegetation cover and limited spawning habitat compared to organisms in the Atchafalaya River Basin (ARB) floodplain, that remains connected to the mainstem Mississippi River. In this study, adult Spotted Gar Lepisosteus oculatus will be collected from UBE and ARB to compare adult Spotted Gar reproductive potential and body condition. Spotted Gar will be collected using a 7.5 Generator Powered Pulsator electrofisher and brought to Bayousphere laboratory for processing. Morphometrics of Spotted Gar will be measured to allow for size comparisons between Spotted Gar residing in UBE and ARB. Gonads will be histologically examined to classify reproductive phase of collected Spotted Gar. Comparing reproductive and body condition characteristics of adult Spotted Gar from ARB and UBE will provide insight into how or if disconnection of floodplains from the mainstem of the Mississippi River impacts adult Spotted Gar reproductive potential and or body condition. Preliminary results indicate that adult ARB female Spotted Gar are larger and possibly more fecund than adult UBE female Spotted Gar.

Assessing Landscape Resistance at a Gulf Coast Essential Fish Habitat Restoration Site

Casey Craig, Florida Fish and Wildlife Conservation Commission
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Juvenile sportfish, including snook and tarpon, are obligate users of nursery habitat provided by salt marsh and mangroves. Juveniles immigrate through creeks and across marsh/mangrove landscapes during extreme high-water events into backwater ponds, which have reduced predator abundance and calm waters due to a lack of connectivity to open water. After reaching an appropriate size, fish will emigrate back across the landscape into open water to continue their life cycle. Essential fish habitat was recently restored in the Cape Haze region of Charlotte Harbor, located on the central Gulf coast of Florida, restoring tidal connectivity to mangrove and salt marsh habitats known to be used by snook and tarpon. The purpose of this study was to assess landscape resistance, habitat connectivity, and utilization by migrating and juvenile fish in restored and natural habitats in Cape Haze. Basal cover and species of vegetation, canopy cover, elevation, sediment grain size, sediment organic matter, and landscape resistance were measured in 18 restored and natural ponds in Cape Haze. Data will be presented on which habitat metrics are most important for determining “hot spot” and “cold spot” locations for the aggregation of juvenile sportfish, including snook and tarpon. Similar work has been conducted in Tampa Bay, though this study is the first for the Cape Haze region.

Restoring the New Jersey Meadowlands - Understanding the Role of Sawmill Creek’s Tidal Wetlands in Minimizing Climate Change Vulnerability

Terry Doss, Meadowlands Research & Restoration Institute - NJ Sports & Exposition Authority
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Sawmill Creek, a 727-acre state wildlife management area comprised of tidal brackish marshes, mudflats, and open water, is a vital resource to both the New Jersey Meadowlands and the surrounding New York/New Jersey Harbor Estuary. Sawmill Creek provides critical functions such as water filtration, storm surge absorption, and wildlife habitat, as well as several forms of public recreation, including boating, fishing, and, in the fall and winter months, duck hunting. Given the multi-faceted benefits that Sawmill Creek provides, ensuring its preservation is paramount to the Meadowlands and the surrounding area. Unfortunately, it has undergone significant ecological change due to development, pollution and climate change, reducing hundreds of acres of vegetated marsh to open water and mudflat. This creates several issues, not the least of which is that these areas, which once stored carbon, are now a carbon source. The loss of vegetation has also diminished wildlife habitats and its ability to provide storm surge protection for nearby infrastructure. As sea level rises and erosion continues, further loss of the vegetated marsh is likely to occur. The situation is dire, but not irreversible. Current data indicates that Sawmill Creek’s remaining brackish marshes are effective at storing carbon, but many questions remain. How much organic carbon is currently stored in the remaining marshes? How much potential might there be for additional carbon storage if the marshes were restored? Conversely, what will become of the organic peat deposits currently stored within the sediment if environmental stressors such as climate change and sea level rise continue to impact the area? The Meadowlands Research & Restoration Institute is working under an EPA-funded study to answer these questions and gather the information needed to restore the marsh to its former functionality amid a changing climate.

Comparing Oyster Restoration Approaches on Grass Island Reef, Aransas Bay, Texas

Emma Clarkson, Texas Parks and Wildlife Department
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Since 2008, the Texas Parks and Wildlife Department (TPWD) has restored over 600 acres of oyster habitat by placing cultch (clean substrate such as rock or shell on which oyster larvae settle and grow) on degraded oyster habitats. While constructing high vertical relief reefs can increase resilience to sedimentation, dredging, and low dissolved oxygen, rising cultch costs can be prohibitive to achieving both areal coverage and vertical relief targets. At Grass Island Reef in Aransas Bay, Texas, TPWD used an experimental restoration design to compare the performance between the “mounding approach” (where cultch is placed in high vertical relief mounds spaced approximately 6 meters apart) and the more cost-efficient “flats approach” (where cultch is placed in a uniform layer with an average depth of 7 cm). Preliminary results indicate that while both restoration approaches successfully increase oyster density as compared to an unrestored reference site, oyster density was higher on mounds versus flats. This information is used to adaptively manage and design future TPWD restoration projects, and additional studies are planned this year to evaluate the impact of dredge harvest on restored reef performance.

The Impacts of pH Manipulation on Pre-Settlement Oyster Larvae in a Hatchery Setting

Leslie Townsell, University of Georgia
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With the decline in water quality, coastal leaders may look to increase the role of hatcheries in resource management and restoration. Aquaculture accounted for more than half of the world’s seafood supply between 1997-2017, with mollusk mariculture contributing to about a quarter of that rise. Georgia was once a leading producer in the nation’s oyster fishery, but its harvest is now the smallest in the Southeast. Oyster aquaculture, supported by a thriving hatchery program, could contribute to the revival of the shellfish industry in Georgia and the regeneration of vital oyster habitats. Most hatcheries depend on intake water from local estuaries, which is subject to coastal acidification. Growers often amend low pH intake with bicarbonate, but the optimum range or upper limit has not been established. To help guide growers, we evaluated the larvae of Georgia’s cultivated variety of Crassostrea virginica and their ability to tolerate high pH conditions. A series of incubation experiments were conducted to measure the growth, survival, and mortality of C. virginica larvae at the University of Georgia, Shellfish Research Lab in Savannah, Georgia. pH levels were manipulated by adding sodium bicarbonate to seawater to identify the optimum pH range. Oyster larvae did not grow or survive at the expected rate based on their life cycle stages measure by sieve size, causing a decline in larval survival and indicating that life cycle day played a larger role in the growth and survival than the pH treatment. We also found mortality was not impacted by pH treatment or life cycle day. This study suggests that maternal lipids may play an important role in supporting C. virginica growth and survival prior to day nine of the life cycle. Lessons learned include that pH may not be the only water quality variable of concern to growers.

Use of Enhancement Structures to Restore Oysters and Increase Biodiversity in the Lower Hudson River

Allison Fitzgerald, New Jersey City University
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In summer 2021, approximately 11 million oyster spat were placed into the lower Hudson River, between Pier 26 and Pier 34 on the west side of Manhattan. These oysters were either set onto large reef balls, or onto recycled shell which was then placed into gabions. In an intricate experimental design featuring 96 reef balls, 80 gabions, 18 textured pilings, and 6 biohuts (gabions wrapped around a pier piling), a team of restoration practitioners and scientists are evaluating the growth and survivorship of oysters as well as the use of the enhancement structures to increase biodiversity of invertebrates and fish in the area. Specifically, the role encrusting invertebrates play as both a deterrent to oyster spat settlement and in oyster growth or mortality will be assessed using image analysis and visual species identification. Early monitoring (after 1 year) shows variability in survivorship that may be linked to tank setting (some structures had very low survivorship), fast growth rates for surviving oysters, and settlement of multiple colonizing species on both gabion and reef ball structures. Community analysis shows a difference between the reef balls and gabions. One particularly important species, the eastern oyster drill Urosalpinx cinerea was found on most structures, and mortality due to drills (as assessed with scars on remnant shells) was high. This is the first of a 5-year monitoring series, and methodology worked out here will allow for a deeper exploration of the ecology of restoration of this key bivalve back into the Hudson Estuary and influence future restoration projects.

Experimental Olympia Oyster Restoration in the Salish Sea; South Puget Sound

Jeff Barney, Pierce County Floodplain and Watershed Services
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To better understand the potential for an Olympia oyster restoration at Penrose Point State Park, this project utilized experimental test plots established in September 2020, recruitment monitoring over the last three years, and long-term monitoring efforts since 2013. The project found that the test plots varied both in the stability of shell substrate and the survival of outplanted oyster seed. This survival of seed was lower than anticipated after 9 months and therefore, the monitoring efforts did not detect any differences between Penrose Point and the reference site at Maple Hollow Park. Additionally, larval settlement of Olympia oysters at Penrose Point and Maple Hollow was extremely low across all years monitored. Although full analyses of community data have not yet been conducted, initial observations indicate a lack of community-level changes. Therefore, we conclude that any future Olympia oyster restoration at Penrose Point State Park should focus on areas with the greatest shell stability and juvenile oyster survival. Furthermore, because the site does not experience regular Olympia oyster settlement, restoration should include the addition of oyster seed. The addition of seed should use methods to reduce mortality due to predation and other factors. Monitoring of this project will continue to determine the continued survivorship of outplanted Olympia oysters and their potential impact on the surrounding community. Troyer S 1 , Behrens M 2 , Becker B 3 , Matheson-Margullis H 3 , Davidson M 2 , Benson A 3 , Cross-Schroeder H 2 , Marvin F 3 , Buxel S 1 1 Harbor WildWatch, Gig Harbor WA, USA 2 Pacific Lutheran University, Tacoma WA, USA 3 University of Washington Tacoma, Tacoma WA, USA

Developing a Coastwide Habitat Suitability Index to Guide Oyster Restoration Planning in Coastal Louisiana

Brandon Champagne, Coastal Protection and Restoration Authority
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Louisiana’s eastern oyster (Crassostrea virginica) population is one of the most valuable oyster resources in the country. In addition to Louisiana’s annual oyster harvest, oyster reefs provide shelter for estuarine species, enhance water quality, and reduce shoreline erosion. Oyster communities and the industries that rely on them are threatened by low population levels caused by stressors like overharvesting, oil spills, and river flooding. Meanwhile, the state faces a land loss crisis as dozens of square miles of coastal marsh erode every year. Recent restoration efforts have constructed oyster living shorelines that work synergistically with natural reef building to protect marsh edges from erosion while contributing to the natural oyster larvae population. Despite the recent implementation of oyster living shorelines in coastal Louisiana, there is insufficient data available on a coastwide scale to inform sustainable oyster restoration planning. A habitat suitability index (HSI) was created to predict future oyster habitat suitability in coastal Louisiana. The model included environmental variables like salinity, fetch, and sediment deposition to predict overall oyster viability in the coming decades. Additional spatial data layers identified potential regulatory constraints such as existing coastal use permits and navigation channels that could otherwise limit project implementation. The resulting tool can help guide both oyster harvesters and restoration practitioners in considering future habitat conditions in their planning efforts. This could improve implementation of restoration projects now and optimize their ecological and environmental benefits in the future.

A Comparative Analysis into the Ecology of Crassostrea Virginica Population Health in the Chesapeake Bay and Gulf of Mexico

Leila Avery, Loyola University New Orleans
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A study evaluating oyster population health of the Chesapeake Bay and Gulf of Mexico using restorative practices protecting sacred native land. Comparing oyster restoration materials and success in different regions of the country. Data on planted oyster reef has been collected over the course of 2 to 5 years examining oyster growth, spat attachment, presence of other invertebrates and predation. The success of a planted oyster reef will include the presence of vertical reef growth, spat attachment, and protection of scared native mounds mitigating land erosion. Most data has been collected in the field at different deployment sites across the Chesapeake Bay watershed and Southern Louisiana close to the Gulf of Mexico. The evaluation of water quality and sustanibility is included in this study.

How Low Can You Go? Expanding Oyster Tidal Niche with Induced Predator Defenses

Carter Lin, Dauphin Island Sea Lab
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Organisms exist within a realized niche constrained by both biotic and abiotic factors. An oyster’s realized niche is constrained by different types of stressors based on their tidal elevation. Higher tidal elevation increases desiccation risk, but can provide a refuge from predation. In contrast, deeper water increases feeding time and accelerates growth but also increases vulnerability to benthic predators. These factors constrain survival at both tidal elevations, setting the boundary for their realized niche. Oysters possess an induced predator defense and will harden their shells in response to predation risk, which reduces their mortality and could allow them to expand their realized niche. We performed an empirical study to determine the optimal tidal elevation for oyster survival and growth in Mobile Bay, AL and to investigate if oysters’ phenotypic plasticity could be manipulated to increase their realized niche. We raised oysters in the presence of blue crab predators (Callinectes sapdius) or in controls without predators, measured changes in their shells, and then monitored their growth and survival at different tidal elevations in seven locations with varying predation regimes. Predator exposure increased oyster survival in all locations and reinforced the elevation-based refuge at 0.36m above the sediment, though some sites saw an additional threshold at 0.62m. Proximity to oyster farms was correlated with higher mortality rates. Our findings suggest non-lethal exposure to predators can bolster oyster restoration and aquaculture and that restoration in intertidal areas can increase oyster survival.

Zinc Incorporation During the Molting Cycle of Blue Crabs, Callinectes Sapidus

Lauren Eagon, Nicholls State University
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Toxic chemicals and heavy metals can have harmful effects on the environment and the organisms within them. In Louisiana, the vast amount of water provides multiple pathways for these xenobiotics to spread and eventually settle. Crustaceans provide a model organism to study the effects of toxic xenobiotics because of high local abundance and exposure from both the sediment and surrounding water. Crustaceans use molting as an important route of elimination for toxic chemicals. Molting is a sensitive growth period where the old exoskeleton is removed, and a new exoskeleton is hardened with calcium carbonate. A divalent cation like calcium, zinc is an essential but toxic metal with both natural and anthropogenic sources that can be harmful to crustaceans. This study aims to identify what stage of the molting cycle zinc enters the exoskeleton of blue crabs (Callinectes sapidus) and the pathway zinc uses for incorporation. Late premolt or “buster” blue crabs are purchased and monitored for completion of ecdysis. Following this removal of the shell, zinc and Pantin’s crustacean saline are injected at three treatment levels: 1.0 mg Zn/ml, 0.5 mg Zn/ml, and 0.0 mg Zn/ml. After two equal injections calculated by wet weight, crabs are harvested for samples of the exoskeleton, epidermis, hemolymph, gill, and muscle. Samples are analyzed for differences in zinc content among treatment levels using ANOVA. We expect to see zinc entering the exoskeleton during post-ecdysial mineralization by way of the calcium transporter using ionic mimicry.

Preliminary Study to Link Sediment Microplastics to the Shorebird Food Web in Caven Point, Liberty State Park (Jersey City, NJ)

Robert Belibrov, New Jersey City University
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Caven Point, a well-known shoreline for bird migration stopovers, is located within the urbanized Hudson Raritan Estuary. This sandy beach and small maritime forest provide food and resting grounds for many species of migratory shorebirds. Being at the heart of an urban estuary, it also provides access to many pollutants, including microplastics. Microplastics have become a more widely researched topic within the field of ecology, and its effects on the environment and species that dwell within the environment are still not very well known. A small preliminary study was performed this summer to try and link the migratory shorebird community to microplastics within the sediment, water, and food web. The study focused on the quantitative collection of the types of birds present at this area, and the identification and assessment of possible microplastics found in bird fecal matter. The species and abundance of shorebirds were observed throughout summer and early fall at several locations across Caven Point. Additionally, samples of sediment and water were analyzed for microplastics. Fecal samples from shorebirds were also collected to assess for microplastics. The data shows that the Canadian goose (Branta canadensis), and Herring gull (Larus argentatus) are the most abundant shorebirds in Caven Point. Along with those species the Great blue heron (Ardea herodias), Great egret (Ardea alba), and Snowy egret (Egretta thula) are also always present. Microplastics were found in the majority of samples, and inferences were drawn with this data to connect the food webs together. This study will be used as a stepping stone to future food web studies in the area, and as a tool to help restore and protect Caven Point. The study will also help to identify the role of microplastics within the shorebird community, and if increases in abundance happen as microplastics move through the trophic levels.

Effect of Sea-Level Rise Induced Salinity and Inundation Regimes on Mature Bald Cypress (Taxodium Distichum) Stands of Southeast Louisiana

Blair Miller, University of Louisiana at Lafayette
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As increased salinity and flooding accompany sea-level rise, freshwater coastal wetlands like bald-cypress stands are becoming ever more susceptible to deterioration, loss of vigor, mortality, and/or transformation to more salt-tolerant herbaceous vegetation. In this study, we assessed how root growth and canopy cover (measured through leaf area index), as two structural properties of bald-cypress stands are affected by different salinity and inundations regimes across 9 sites distributed in the Barataria and the Terrebonne/Atchafalaya estuaries. Root growth was measured using ingrowth cores, while leaf area index estimated from a diffuse light radiation analyzer (LI-COR LAI-2000). Both were measured quarterly from May 2022 to December 2022. Preliminary results from two quarterly measurements indicate that canopy cover is not affected by salinity. However, inundation has had an effect as plots with the highest average water level during the past 3 years showed a decrease in canopy cover from the spring to the summer season. Our presentation will also examine emerging results from root growth measurements.

Proactive Landscape Coastal Habitat Protection in Alaska

Michael Daigneault, U.S. Fish and Wildlife Service
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The U.S. Fish and Wildlife Service Coastal Program, in partnership with Alaska land trusts and Alaska Native organizations, has been focused on proactively protecting intact, functioning coastal habitat across Alaska for over 20 years. Our goal is to protect functioning ecosystems in advance of anthropogenic impacts that require restoration. Alaska's climate is changing at a rate of 2-3 times faster than the continental U.S., and these protected coastal habitats provide a variety of ecosystem services and nature-based coastal resilience. Over the past two decades, the Coastal Program and our partners have focused conservation efforts in coastal areas of Southeast, Southcentral, and Southwest Alaska - these efforts have resulted in the protection of significant acreage of high quality coastal habitat. These habitats support an abundance of fish and wildlife species: resident, anadromous, and marine fish, resident and migratory birds, and resident mammals. Further, these habitats and species support Alaska Native food security, a cultural connection to the land, and recreational and commercial harvests that are foundational to Alaska's economy. This poster celebrates the coastal habitat conservation successes over the history of Alaska's Coastal Program and provides context for the countless fish and wildlife species that have benefitted from this proactive conservation. We also recognize that many of Alaska's coastal areas are not addressed by this Program - Alaska's coastal habitat protection needs are great and we endeavor to expand the Program to fulfill the needs across all of Alaska.

Thermal Tolerance Variation in Young-Of-The-Year Winter Flounder Across the Southern New England Region

Geresa-Leigh Luke, Stonybrook University
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Warming estuaries driven by climate change pose a risk for early life stages of coastal fish species. Water temperature increases can induce thermal stress in juveniles symptomatic of growth inhibition, increased respiration, and mortality thus reducing recruitment into the offshore adult population. This research aims to identify thermal tolerance variation among juvenile Winter Flounder subpopulations within the Southern New England region. A common garden laboratory experiment was conducted using Young-of-the-Year Winter Flounder from Boston Harbor, MA, Narragansett Bay, RI, Shinnecock Bay, NY, and Sandy Hook Bay, NJ. The test subjects from each population were placed in individual bowls in 3 recirculating seawater systems and acclimated to 14, 20, or 24C. Over the course of 5 weeks, length and weight were measured to determine temperature’s effect on growth rates. Additionally, opercular flaps were recorded on video and used as a proxy for ventilation and respiration rates. Growth was strongly influenced by temperature and fish population. Fish from Shinnecock Bay and Narragansett Bay, grew at the highest rate, with positive growth observed for all populations at temperatures of 14C and 20C, with most populations experiencing negative growth rates at the warmest temperature (24C). As expected ventilation tended to increase as a function of temperature, but the response varied among the populations tested. Further statistical analysis of the preliminary data is still ongoing. The preliminary results suggest that growth and ventilation vary across populations of Winter Flounder and response to warming conditions may vary by location. This research aims to understand how juvenile fish respond to climate change and the final conclusions will be used in modeling efforts to inform coastal fisheries management and support the resiliency of Winter Flounder.

Comparison of Finfish and Crustacean Assemblages Among Established Marsh Terraces, New Marsh Terraces and Open Water in a Restored Brackish Marsh

Shasta Kamara, Nicholls State University
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Louisiana has lost approximately a quarter of coastal lands that were present in 1932 from subsidence, disconnection of the Mississippi River from its floodplain and other natural and anthropogenic factors, necessitating restoration activities. One such technique is the creation of marsh terraces from local sediments in areas where marsh has been degraded to open water. Marsh terracing aids in slowing land loss as it reduces the exposure of surrounding marshland to wave energy. This study evaluated the influence of marsh terraces on finfish and crustacean assemblages in a brackish marsh east of Golden Meadow, Louisiana. The study region contained three habitats, new terraces built in 2022 (1.1 km^2), established terraces built in 2017 (0.57 km^2) and an adjacent open water area (0.44 km^2). Gee’s® minnow traps, experimental mesh gill nets and a shrimp trawl (1.8 m wide) were used to sample finfish and crustaceans along terrace edges, in channels between adjacent terraces and in open water. Sampling occurred twice a month May through October 2022. Finfish and crustaceans were identified to species, counted and measured (mm). Catch per unit effort was calculated as number of individuals collected per unit of effort for each gear type. Fundulus grandis (Gulf Killifish) had higher mean CPUE in the minnow traps in the established terraces (0.34 mean CPUE ± 0.11 Standard Error) than the new terraces (0.02 ± 0.01). The difference between the established and the new terraces may indicate that the perceived habitat quality for some species may change over time. Examining the finfish and crustacean assemblages provided insight into possible ecological effects of terraces and how those effects may change over time.

Tracing Energetic Connectivity Across Restored and Reference Salt Marsh Landscape Mosaics

Katherine Loesser, Louisiana State University
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The rapid rate of coastal land loss in Louisiana spurred the implementation of numerous federally authorized marsh restoration projects in the state. Evaluations of coastal wetland restoration often focus on nekton diversity and abundance as key metrics of success. However, establishment of trophic linkages and food web structure are critical to ensuring the return of proper ecosystem function. We used a stable isotope-based approach to quantify the degree of basal resource overlap between marsh platform, creek, and channel nekton communities at created and reference salt marshes in southeastern Louisiana. Using carbon, nitrogen, and sulfur stable isotopes, we constructed three-dimensional niche ellipsoids for each community. For each site, we compared niche breadth, shape, and overlap between communities, and used the degree of overlap to determine the strength of energetic connectivity across habitat mosaics. We then compared energetic connectivity between and within created and reference sites to evaluate the success of marsh creation in re-establishing trophic structure. As coastal restoration grows increasingly important, understanding the ability of restoration efforts to re-establish food web structure is critical to effectively evaluating restoration and implementing adaptive management practices.

A Survey of Benthic Invertebrates in Saw Mill Creek, Hackensack River NJ

Ebony Chilin, New Jersey City University
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The Meadowlands are a large expanse of saltwater marshland in northeast NJ, bordering the Hackensack river and Hudson River. Much of the Meadowlands is impacted by the urbanized area surrounding it, and by past impacts such as tidal gates that separated parts of the marsh from the main stem. One of the many tributaries running throughout the marsh is Saw Mill Creek, which was closed by tidal gates until the 1950s when a storm surge broke the gates and re-flooded the marsh. Slowly this marsh has been naturally restoring itself, all while the native Spartina grasses fight with the invasive Phragmites for space. Saw Mill creek is home to many different types of benthic invertebrates, fiddler crabs, fish, and more. These animals are very important for life on the mudflats to be productive. Benthic invertebrates allow for bioturbation to occur and have more biodiversity within mudflat than in the deeper channels. Whereas Fiddler crabs allow for oxidation to occur within mudflats, and are found closer to the vegetation. Using grab samples and hand capture, a survey of the biodiversity of the mudflats in Saw Mill Creek was obtained in July 2022. Grab samples assessed infaunal invertebrate diversity along a depth gradient in 3 locations, while fiddler crab behavior and population demographics were also observed at the same locations. Benthic invertebrates were more diverse as distance from the main stem increased (further back into the marsh) and changed along a depth gradient. Various polychaetes as well as Macoma tenta clams were abundant infaunal organisms. This data will be used by various restoration practitioners as the Hackensack River is restored as a Superfund site over the coming years.

Sustainable Ecological Enhancement of Port Infrastructure: Port of San Diego

Heather Weitzner, ECOncrete
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In 2019, under the framework of the Blue Incubator Program, the Port of San Diego approved a two-year pilot project with ECOncrete, an ecological engineering company developing innovative bio-enhancing concrete infrastructure for the coastal, marine, and offshore industries. The main objective of the project was to develop a specific design to address the ecological enhancement of the riprap armoring protecting Harbor Island, with the primary goal of creating well-defined local ecosystems that mimic natural rock pools and provide for a favorable environment in which to develop an abundant and rich diversity of marine flora and fauna. ECOncrete's technologies for enhancing the ecological value of fully structural concrete is based on three aspects: the materials composition, the surface texture, and the three-dimensional design. The combination of these three principles working in synergy has proven to achieve optimal results when combining ecological enhancement along with structural performance. In 2021, ECOncrete launched the first installation of 74 interlocking single-layer COASTALOCK armor units across two riprap sites along the San Diego Bay shoreline. The units will provide structural, ecological, and community engagement benefits. ECOncrete will conduct ecological and structural monitoring every six months for the first two years. Initial monitoring results are overwhelmingly positive, with the marine ecosystem thriving only months after successful installation, outperforming expectations. Monitoring results included 31 sessile species, 10 mobile invertebrates, and 4 species of fish. In addition, dozens of juveniles of the Nudibranch Aplysia californica were found in the COASTALOCK cavities. With this project, the Port of San Diego and ECOncrete aim to provide an example of inclusive design for coastal protection and port infrastructure which can be applied to urban, natural, and working waterfronts globally.

Mapping Habitat Suitability for Culturally Significant Plants in the South Slough Watershed in Oregon

Tehani Malterre, NOAA/South Slough National Estuarine Research Reserve (student at University of Hawaii at Manoa)
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The National Estuarine Research Reserve (NERR) system is a national network of estuaries co-managed by NOAA and coastal state agencies. In 1974, the South Slough NERR (SSNERR) in Coos County, Oregon became the first of 30 sites in the NERR system designated for protection and research. This project specifically focuses on the Wasson Creek basin, which is a 530-acre section of the SSNERR watershed system that directly feeds one of the main tributaries to the South Slough and has been the subject of ongoing restoration efforts after years of successive timber harvests. Plants such as beaked hazel (Corylus cornuta) and associated plant communities were managed for abundance by the miluk coos and other Native peoples of the Oregon coast since time immemorial and have been severely impacted by timber harvests and inadequate forest management in the past century. These species, along with many more, are culturally important to local Native peoples including members of the Confederated Tribes of the Coos, Lower Umpqua, and Siuslaw Indians (CTCLUSI). To aid in these restoration efforts, this habitat suitability mapping project utilizes ArcGIS to create a map of areas within the Wasson Creek basin that can support some of these culturally important species (e.g. beaked hazel). Suitability is based on environmental parameters such as soil type, drainage, aspect, slope, elevation, accessibility for stewardship and cultural use, and surrounding vegetation. This project was completed by combining GIS data from the Oregon Department of State Lands (DSL) and GIS Living Atlas with literature research, personal communication with Tribal members, and site visits to existing populations and proposed suitable locations. The information and maps generated by this project will be used to inform management processes within the Wasson Creek basin and hopefully aid in Tribal accessibility to these natural cultural resources.

City of Charleston, SC Church Creek Stormwater Basin Study: Restoration of Tidal Flow and Flood Mitigation

Robert Horner, Weston & Sampson
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In one of the fastest growing areas in the historic City of Charleston, South Carolina, recurrent flooding from past development practices brought all new development to a screeching halt for over a year in the popular West Ashley area that drains to Church Creek. The Church Creek drainage basin is a 15,000-acre area including residential and commercial development and significant transportation corridors. The basin also includes significant freshwater and saltmarsh wetlands and tracts of undeveloped property. Based on significant flooding, the City implemented the moratorium on development and commissioned a study by Weston & Sampson to evaluate existing conditions and develop solutions to prevent future flooding that would allow growth while protecting transportation corridors and private property. Weston & Sampson evaluated past studies, upgraded the hydraulic model, and developed seven initiatives that would fix the flooding problems if implemented. One of these initiatives is to restore tidal flow to the system through upstream and downstream connections via Lake Dotterer and an impounded wetland. The capacity of Lake Dotterer as a stormwater facility is much larger than would typically be required to serve the surrounding neighborhoods and urban area. This overall area is approximately 50 acres and was formerly part of the estuarine system which connected Church Creek with the Stono River. The study proved under normal conditions that a high enough tide can cause upstream flow in the channel. Additionally, the study proposed that culverts be equipped with surge protection devices that would allow for two-way flow during normal conditions but would close during abnormally high tides. Ultimately, this study shows the potential for re-establishment of connection between Church Creek and the Stono River, restoring tidal flow to a currently impounded wetland, and adding adaptive capacity to a currently overwhelmed stormwater system.

Monitoring Animal Use of Stabilized Shorelines with Wildlife Trail Cameras

Paul Sacks, Biology Department, Coastal and Estuarine Ecology Lab, University of Central Florida
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An important purpose of living shoreline stabilization, in addition to reducing erosion, is to restore ecosystem services to previously degraded shorelines. This study used wildlife trail cameras to assess the impact of 3 different living shoreline stabilization materials on terrestrial fauna along 3 kilometers of estuarine shoreline in Canaveral National Seashore, on the east coast of central Florida. Stabilization included mangroves in the upper intertidal, smooth cordgrass in the mid-intertidal, and a breakwater in the lower intertidal. Breakwater treatments included Naltex™ (plastic) shell bags, galvanized wire crab pot mesh soft gabions, and cement-jute volcanos. Eroded with minimal vegetation and non-eroded, vegetated shorelines constituted the negative and positive controls, respectively. Trail camera video clips were recorded from early February through June 2022. Raccoons, followed by feral hogs, were the most frequently observed mammals at each of the treatments; great blue herons were the most frequently observed bird. No animals avoided the restoration materials. White-tailed deer foraged on a few mangrove leaves, while invasive feral hogs dug up and displaced plants and Naltex™ shell bag breakwater materials, but not the newer, plastic-free materials. The National Park is actively trying to remove hogs. Overall, these shoreline stabilization strategies did not interfere with behaviors of wading birds and terrestrial animals.

Experimental Oyster Reef Restoration along the Mississippi Coastline

Amy Yarnall, USACE Engineer Research and Development Center
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The significant loss of oyster reefs in the Northern Gulf of Mexico has far-reaching consequences. Depleted reefs impact commercial and recreational fishing and reduce essential fish habitat for commercial and recreational nekton species. Historically, reefs served as pivotal structures supporting a huge range of ecosystem services and processes that make up a healthy coastal system. An evaluation of active oyster reef restoration methodologies is needed to guide future restoration efforts. This poster describes a large-scale replicated oyster reef experiment that will be conducted along the Mississippi coastline. Objectives of this research are to investigate methods for optimizing oyster habitat restoration from two different placement areas within the Mississippi Sound, and to evaluate whether restored oyster reefs enhance habitat for important commercial and recreational fish species and to evaluate the impact of oyster reef creation on federally designated critical habitat for Gulf Sturgeon. This project is a partnership between The University of Southern Mississippi and the U.S. Army Engineer Research and Development Center’s Environmental Laboratory, funded through the Ecosystem Management and Restoration Research Program.

Oyster Reef Restoration Using Novel Biodegradable Elements in the Indian River Lagoon, FL

Luciana Banquero, University of Central Florida
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In the field of ecosystem restoration, there is increasing interest in finding effective biodegradable alternatives to conventional plastic materials to minimize plastic introduced to restored environments. For example, BESE-elements® (Biodegradable Elements for Starting Ecosystems), which form 3D lattice sheets made of potato starch with oyster shell (Crassostrea virginica) attached, have successfully restored degraded oyster reefs on Florida’s east coast. However, preparing these materials for restoration is time intensive, leading restoration practitioners to look for novel biodegradable options that would be more feasible at larger scale. BESE-reef paste is a new technology that aims to enhance shellfish recruitment when used to restore reefs without the need to attach shell. Six oyster reefs were restored in June 2022, three using BESE-elements® with attached oyster shells and three using BESE-elements® with oyster reef paste. Cement was coated on BESE-elements as a control for the paste. Reefs were monitored weekly over the course of a month following deployment and then quarterly. Data was collected on reef paste and cement retention, as well as oyster recruitment. The objective of this project was to determine which method would be the most effective at recruiting oysters, while maximizing volunteer friendliness and cost effectiveness. Preliminary data shows a significant difference between treatments in oyster recruitment four weeks post-deployment (ANOVA p-value: 0.0043). BESE-elements® with oyster shells had higher oyster recruitment on studied reefs. Regarding volunteer friendliness, BESE-elements® with reef paste took less time to make per mat than BESE-elements® with oyster shells, but many volunteers obtained chemical burns during community oyster reef restoration material preparation events at Marine Discovery Center in New Smyrna Beach, FL while making BESE-reef paste mats. Sourcing materials for reef paste was more expensive than the oyster shell treatment aside from BESE-elements®. Monitoring will be ongoing until June 2023 to examine longer-term trends.

Dynamic Living Shorelines: An Innovative Union of Shoreline Protection and Habitat Enhancement

Joshua Hansen, Underwood & Associates
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Sea-level rise and increasing shoreline development have amplified the demand for more resilient protection against shoreline erosion. Soft engineering practices such as living shorelines have shown to be more resilient during hurricanes than hard engineering counterparts (e.g., bulkheads, revetments), require less maintenance over time, and provide effective protection against erosion. The primary advantage living shorelines have over conventional shoreline erosion control structures is their ability to provide ecological services such as habitat provision and trophic transfer and to act as a tertiary buffer for upland runoff and groundwater. For the past 25 years, Underwood & Associates has been developing the innovative Dynamic Living Shoreline (DLS) technique. This technique creates a complete coastal profile of headlands, beach, backshore, and dune systems, providing resilient shoreline protection and enhancing habitat. Infaunal communities adjacent to our past projects have increased biomass, density, and diversity after project completion. Additionally, the biomass of polychaetes declined after project completion, suggesting a transition toward stable infaunal communities at our projects over time. In the past, gray infrastructure contributed solely to permanent habitat impacts, and mitigation was required to be found elsewhere. Our headlands are our advancement on conventional breakwaters. They utilize a well-graded mixture of sands, gravels, cobbles, and boulders that interlock to create a cohesive unit that can provide the same shoreline protection as a rubble mound. Including smaller sediment sizes permits shallower design slopes, which in turn greatly reduce wave reflection deleterious to the nearshore habitat while supporting the growth of native marsh grasses, and having a natural appearance. The project’s resiliency benefits from the wetland grasses, which create an erosion-resistant turf that functions with greater resiliency than geotextiles. This poster will explain the main features of a dynamic living shoreline with visual aid based on our 25 years of designing and constructing these projects.

True Restoration: Regenerative Stream Channel (RSC) As An Integrated Approach To Restore River-Wetland Corridors To Pre-Civilization Times.

Chris Becraft, Underwood & Associates
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Worldwide, valley floors were once dominated by laterally unconfined river planforms that featured dynamically stable, morphologically complex, multi-threaded channels with vegetated bars, islands, and floodplains. These river-wetland corridors had a high degree of connectivity between subsurface and surface flows, with groundwater tables at or near the surface, and were much wetter than the modern, artificially drained river valleys to which we have become accustomed. These corridors have since been nearly annihilated (>80%) due to various anthropomorphic activities. Conventional stormwater management practices grounded in industrial design have neglected integration with ecosystem processes, economics, and aesthetics. The general public and river managers alike have since lost sight of how restoration goals should appear. Hard, structural methods have led to the dysfunction of many former river-wetland corridors, as they cause erosion and stream channel degradation. All of this leads to an increasing spiral of degradation in which local governments are forced to spend scarce public funds on remediation measures. Alternatively, using nature-based stream restoration techniques to create a dependable, open-channel conveyance with pools and riffle-weir grade controls is a regenerative design that harkens back to pre-civilization conditions. These elements result in a system of chemical processes and biological mechanisms that can have beneficial, positive feedback effects on the ecology of a drainage area. This approach results in low-energy stormwater discharge delivery, potential volume loss through infiltration and seepage, increased temporary water storage, restored groundwater levels, increased vernal pool area, improved water quality treatment, improved local micro-habitat diversity, and provides a significant aesthetic value. An investigation has found that RSCs have enhanced stream function at the reach scale, removing 73.8% of the suspended sediment, 49.7% of the total nitrogen, 25.7% of the nitrate, 45.8% of the total phosphorus, 44.8% of the phosphate, and 48.3% of the ammonium.

Understanding and undertaking the science needed to support Puget Sound ecosystem recovery

Scott Redman, Puget Sound Partnership
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The Puget Sound Partnership, a Washington State agency, provides backbone support for collective, cross-sector efforts to protect and restore the Puget Sound ecosystem. In an evolution of the science-oriented approaches that began developing nearly 40 years ago, the Partnership convenes an advisory Science Panel and includes a staff team devoted to coordinating the research, modeling, and monitoring needed to support ecosystem recovery efforts. The Science Panel, with staff support, develops Science Work Plans that identify priority science work actions and broader recommendations to improve ongoing science. The Science Work Plan for 2020-2024 guides the Partnership's investments in scientific investigations and the work of the Panel and staff to engage the science community in support of Puget Sound ecosystem recovery. To address science needs expressed by various entities and to achieve the Panel's objectives for scientific efforts, the Panel identified 15 top priority science work actions for 2020-2024, which fall into four categories: (1) human-biophysical interactions; (2) effectiveness of recovery interventions; (3) ecological conditions and effects; and (4) science-based decision support. The Science Work Plan for 2020-2024 also specifies the following broader recommendations to improve ongoing science: (a) collaboratively broaden and improve the knowledge network that supports Puget Sound ecosystem recovery; (b) improve incorporation of Indigenous knowledge into science and monitoring efforts; (c) develop capacity and coordinate efforts to assess and report on ecosystem conditions and the effectiveness of recovery interventions; (d) coordinate production and use of interdisciplinary research that explores and emphasizes the integrated nature of socio-ecological systems; (e) build and sustain robust programs and relationships across science-policy interfaces to inform recovery; (f) communicate science findings clearly and to the appropriate audiences; and (g) develop and analyze alternative future scenarios to explore and express desired futures and evaluate trade-offs among possible approaches.