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Trophic Ecology Of A South Carolina Estuarine Predator Guild, Shane John Molander

Electronic Theses and Dissertations

Estuaries are among the world’s most productive ecosystems in the world and are characterized by the convergence of two distinct habitats, creating a mosaic of environmental conditions from inland rivers to the nearshore ocean. Many fishes occupy estuaries during various life stages for growth, reproduction, or foraging, and may reside in them seasonally. The co-occurrence of species, particularly upper-trophic level carnivores, can result in competitive interactions for prey resources within a shared environment. Identifying the degree of these interactions as well as understanding basal energy consumption can inform food web dynamics and how overlapping species use shared spaces. I used …

Movement And Distribution Dynamics Of Predatory Fishes In The St. Lucie Estuary, Sarah Fae Leonowicz Torre

Electronic Theses and Dissertations

Estuaries are productive but highly variable ecosystems that support recreationally and commercially valuable fisheries, as well as species of conservation concern. However, coastal development, habitat loss, altered freshwater inflow, and declining water quality can modify the environmental gradients that structure fish distributions. In the St. Lucie River and southern Indian River Lagoon, located in southeast Florida, managed freshwater discharges, watershed runoff, shoreline modification, and degradation of essential fish habitats (e.g., seagrass, oyster, and mangrove forests) have altered estuarine conditions.

This dissertation evaluates how four estuarine fish species with contrasting life histories respond to environmental variability, hydrologic disturbance, and habitat structure …

Chesapeake Bay Water Clarity: Challenges And Successes, Jessica S. Turner, Carl T. Friedrichs, David B. Parrish, Kelsey A. Fall

OES Faculty Publications

The Chesapeake Bay is a large estuarine system spanning multiple jurisdictions and serves as a model for estuarine health worldwide. Historically, nutrient loading degraded water quality, prompting the need for regulation. Water clarity, one component of water quality, is vital for benthic communities and serves as a key indicator of overall ecosystem health. Here, physical resuspension and salinity gradients, nutrient and sediment inputs, production of organic detritus by phytoplankton, and benthic communities all interact to drive clarity patterns, with high spatial variability. Trends over the last 50 years show improvement, though with a temporary increase in organic detritus in response …

Investigating Spatial And Seasonal Differences In Microgastropod Assemblages Within The Little-Studied Camamu Bay, Brazil: A Potential Bioindicator For Remote Tropical Areas?, Francisco Kelmo, Sol De Maria Cesar Ferreira, Eduardo Henrique Galvão, Martin J. Attrill

School of Biological and Marine Sciences

This study investigates spatial and seasonal variation in the assemblages of benthic microgastropods (snails < 5–10 mm in length) within a poorly studied tropical bay. As these organisms are abundant, diverse and relatively easy to sample, with well-established taxonomy, they may prove a highly suitable group for ecological studies in such areas. Sediment samples were collected from three river basins in Camamu Bay, Brazil, during the wet and dry seasons. A total of 132 microgastropod species was recorded, demonstrating high diversity. The most abundant species were Eulithidium affine, Bittiolum varium, Cerithium atratum, Vitta virginea and Schwartziella bryerea. The least abundant species were Tenaturris gemma, Turbinella laevigata, Petaloconchus erectus, Parviturboides interruptus and Vitrinella cupidinensis. Statistical analysis revealed significant seasonal and spatial differences in diversity and assemblage composition, which correlated with environmental gradients. The results suggest that microgastropods are a suitable component of the biota for ecological and applied studies in marine sediments, particularly in remote tropical locations where full macrofaunal analysis may be challenging. Whilst further testing across impact gradients is needed, this approach offers a practical solution for ecological investigations in remote regions with limited taxonomic expertise and highlights microgastropods as a useful indicator taxon for impact biomonitoring in tropical marine sediments.

Monitoring Shifts In Estuarine Microbial Communities: A Dna-Metabarcoding Approach, Ashley M. Reaume

Graduate Studies Theses and Dissertations 2026

Estuarine microbial communities, including plankton, algae, and bacteria, play important roles in nutrient cycling and food web structure. They are sensitive to changes in abiotic conditions, and shifts in community composition can provide insight into estuarine ecosystem functioning in the face of various physiochemical and anthropogenic stressors. Therefore, monitoring these communities is essential for understanding and maintaining estuarine health. DNA metabarcoding is an emerging technique for enhancing biological monitoring, allowing for the detection of multiple species within a single sample. This dissertation first focuses on how methodological decisions impact DNA metabarcoding results and then implements these optimized methods to perform …

Linking A Seasonal Freshwater Prey Subsidy To The Body Condition Of An Estuarine Consumer In A Subtropical Coastal River, Jordan A. Massie, Ryan J. Rezek, W. Ryan James, Rolando O. Santos, Natasha M. Viadero, Ross E. Boucek, Jennifer S. Rehage

Marine Science

Movements of fishes among habitats often correspond to shifting resource availability and can occur in response to fluctuating freshwater inflows in coastal systems. Seasonal availability of prey can provide resources that increase fitness, yet hydrologic variability can influence the movements of both consumers and prey. Shifts in the timing/magnitude of prey availability driven by climate and water management may lead to a resource mismatch, carrying consequences for growth, survival, and reproduction. Here, we examined how seasonal/interannual variation in prey biomass (sunfishes, Lepomis spp.) affects the body condition of Common Snook (Centropomus undecimalis) in Everglades National Park. Further, we investigated how …

Long-Term Patterns In The Relative Abundance Of Common Snook As A Factor Of Shifting Environmental Conditions In The Florida Coastal Everglades, Jordan A. Massie, Ryan J. Rezek, Rolando O. Santos, W. Ryan James, Natasha M. Viadero, Ross E. Boucek, Jennifer S. Rehage

Marine Science

Objective Environmental variability as a factor of climate change and water management can result in fluctuations in the abundance and distribution of fish populations from year to year, with either negative or positive effects depending on behavioral and physiological requirements and the ability to adapt to changing conditions. Variability in water levels can also influence prey availability, affecting predator abundance in seasonal foraging areas. In this study, our objective was to better understand how environmental variation has affected the relative abundance of Common Snook Centropomus undecimalis in the freshwater/estuarine habitats of Everglades National Park. Methods Electrofishing data over 17 years …

An Investigation Of Hydro-Morphological Changes At The Estuarine Outlet Of Kitchener Drain, Northern Coast Of Egypt, Nada Mansour, Karim Nassar, Mahmoud El-Gamal, Tharwat Sarhan

Mansoura Engineering Journal

In recent years, sedimentation and coastline erosion have occurred in the Kitchener Drain, where its outflow meets the Mediterranean Sea. Several measures have been taken to mitigate the impact of these problems. Excavation continues toward the drain's outlet, and there have been multiple stages of hard protection work, such as groins along the drain's eastern and western banks. What would happen if the working near the drain was kept, where accretion and erosion are most severe. The Coastal Modelling System (CMS) was used to find it out. The two-dimensional hydrodynamic circulation model known as the CMS is outfitted with modules …

Exploring Fisheries Species Distribution Shifts In Response To Freshwater Inflow Through The Bonnet Carré Spillway Using Species Distribution Models, David T. May

Master's Theses

The Bonnet Carre Spillway (BCS) is a flood control structure on the Mississippi River (MR) ~52 km upstream of New Orleans. The BCS protects downstream communities from MR flooding by diverting floodwaters into Lake Pontchartrain when the MR exceeds 5.18m flood stage. Diverted waters flow east into the Mississippi Sound (MSS), introducing turbid, nutrient rich freshwater to the estuary before draining into the Gulf of Mexico. BCS openings have become much more frequent in the last decade, though little work has been done to explore the impact of the BCS on nektonic fisheries species. Here, a series of seasonal Maximum …

A Comparative Study Of Land Use Regulations And Impact On Coastal Estuaries, Mabel W. Dadzie

All Theses

The study presents a mixed method and longitudinal assessment of land cover change, estuarine land loss, and policy implemented to address the past and anticipated estuarine losses in the Cooper River and North and South Santee watershed over the past twenty years. This study uses National Land Cover Dataset from 2001 to 2021, NOAA’s SLR projection data and planning documents from 1990 to 2025 to examine policy evolution among ten major themes. The results illustrate significant changes in land cover, notably the transition of wetlands, agriculture, and forests to developed land, as well as an evident spike in the integration …

Assessing The Impact Of Historic Mining On The Geochemistry Of Sediments In The Camel Estuary, Cornwall, U.K., Gregory Price, Matthew Cleave

School of Geography, Earth and Environmental Sciences

This investigation focusses on the geochemical properties of surficial sediments in the Camel Estuary, Cornwall, UK. Thegeochemistry of the samples were determined by XRF and data for Sn, As, Cu, Pb and Zn are presented. The data for Pb, Zn andAs shows a down estuary reduction, probably resulting from a combination of increasing distance from a presumed metalliferousmining source and mixing with marine sediments. The highest concentrations for As (48 ppm) and Zn (304 ppm) exceedsediment quality guidelines. Cu and Pb values are below the sediment quality guidelines. Although elevated Sn concentrations areseen in the middle part of the estuary, …

The Impact Of Seasonal Hydrological Disturbances On The Presence And Formation Of Toxic Cyanobacteria Blooms In Coastal Louisiana, Courtney Nicole Hammond, Sibel Bargu, Caitlin R.R. Turner, Matthew Hiatt, John R. White

Faculty Publications

Estuaries in the Gulf, especially Lake Pontchartrain Estuary in southeastern Louisiana, USA, are experiencing significant changes due to climate change and coastal restoration efforts. Lake Pontchartrain Estuary receives nutrient-rich Mississippi River water through a controlled diversion called Bonnet Carré Spillway (BCS), which has been associated with toxic cyanobacterial blooms (cyanoHABs). This study examines the seasonal factors influencing cyanoHABs in the Lake Pontchartrain Estuary when the BCS is closed, addressing gaps in the understanding of HABs related to other physical drivers. Field samples collected in 2021, during the closure of the spillway, revealed significant evidence of seasonal variations in cyanoHAB formation. …

Investigating Fish Communities As Part Of The Food Web In Artificial Tidal Wetland Ponds Of Humboldt Bay, Ca, Lily M. Olmo

Cal Poly Humboldt theses and projects

In the face of global wetland loss, artificially created wetlands have the potential to restore ecosystem services for humans while also providing habitat for fish and wildlife. This study explored fish communities in three understudied artificial wetland ponds that are connected to Humboldt Bay in northern California and known to be important wildlife foraging areas. The objectives of this research were to 1) Characterize the environmental conditions of each pond, 2) Calculate the relative catch, richness, diversity, and biomass of fish in each pond, 3) Describe the movement of fish into and out of the ponds with the tides, and …

A Blueprint To Greener Shorelines: Advancing The Effectiveness, Sustainability, And Widespread Adoption Of Coastal Nature-Based Solutions Through Transdisciplinary Research, Taylor M. Sloey, Sierra Hildebrandt, Rebecca L. Morris, Matthew V. Bilskie, Aaron Bland, David Bushek, Gabriella Dipetto, Daniel Elefant, Vincent Encomio, Ramin Familkhalili, Christine Hladik, Danielle Kreeger, Avery B. Paxton, Cindy M. Palinkas, Latina Steele, Andrew Scheld, Daisuke Taira, Jason D. Toft, Armando J. Ubeda, Christine Whitcraft, Donna Marie Bilkovic

Biological Sciences Faculty Publications

Coastal nature-based solutions (NbS) have emerged as powerful tools to enhance sustainable development and ecological restoration goals. As a rapidly growing field spanning across social, political, ecological, economic, and engineering disciplines, it is critical that researchers working in coastal NbS regularly attempt to identify emerging focal areas for scientific inquiry. Following the 27th Biennial meeting of the Coastal and Estuarine Research Federation, we provide a transdisciplinary perspective (including biologists, engineers, oceanographers, geoscientists, economists, and facilitators of workforce training programs) of pertinent research questions that, if answered, will advance the effectiveness, sustainability, and widespread adoption of coastal NbS. These suggestions for …

Spatial And Environmental Drivers Of Temperate Estuarine Archaeal Communities, Emily Cocksedge, Michael Stat, Alessandra L. Suzzi, Troy F. Gaston, Megan J. Huggett

Research outputs 2022 to 2026

Archaea play a crucial role in the global biogeochemical cycling of elements and nutrients, helping to maintain the functional stability of estuarine systems. This study characterised the abundance and diversity of archaeal communities and identified the environmental conditions shaping these microbial communities within six temperate estuaries along approximately 500 km of the New South Wales coastline, Australia. Estuarine sediments were found to exhibit significantly higher species richness than planktonic communities, with representative sequences from the Crenarchaeota phylum characterising each environment. Ordinate analyses revealed catchment characteristics as the strongest drivers of community variability. Our results also provide evidence supporting distance-decay patterns …

Microplastic Accumulation In The Marsh Periwinkle (Littoraria Irrorata), Sarah Keaton, Hannah Lukhard, Eli Windy, Manar Hasan

DePaul Discoveries

Contamination of oceans by microplastics (mm) currently poses a major threat to aquatic and terrestrial ecosystems worldwide. Recent attention towards this issue has raised questions about the extent to which microplastics have accumulated in the environment, and has led to an increase in studies on the effects of microplastics in various organisms. However, levels of contamination in protected natural areas are still largely unexplored, yet can offer an important empirical perspective on the issue. In addition, little is known about the potential effects of microplastics on behavior in the field. This research was conducted within the protected ACE Basin National …

The Impacts Of Anthropogenic Activity And Climate Change On The Formation Of Harmful Algal Blooms (Habs) And Its Ecological Consequence, Zhangxi Hu, Aifeng Li, Zhun Li, Margaret R. Mulholland

OES Faculty Publications

No abstract provided.

Observations Of Lateral Salinity Variability At A Deltaic-Bay Transition Zone, Mobile Bay, Alabama, Clara Oxford, Brian Dzwonkowski, Josh Goff

Gulf and Caribbean Research

No abstract provided.

Unraveling Sources Of Cyanate In The Marine Environment: Insights From Cyanate Distributions And Production During The Photochemical Degradation Of Dissolved Organic Matter, Rui Wang, Jihua Liu, Yongle Xu, Li Liu, Kenneth Mopper

Chemistry & Biochemistry Faculty Publications

Cyanate is a nitrogen and energy source for diverse marine microorganisms, playing important roles in the nitrogen cycle. Despite the extensive research on cyanate utilization, the sources of this nitrogen compound remain largely enigmatic. To unravel the sources of cyanate, distributions and production of cyanate during photochemical degradation of natural dissolved organic matter (DOM) were investigated across various environments, including freshwater, estuarine, coastal areas in Florida, and the continental and slope regions of the North American mid-Atlantic Ocean (NATL). Cyanate production was also examined during the photochemical degradation of exudates from a typical strain of Synechococcus, an important phytoplankton …

Intra-Decadal Increase In Globally-Spread Magallana Gigas In Southern California Estuaries, Marah L Wolfe, Chelsea M Bowers-Doerning, Anabell Espinosa, Ty Frantz, William J Hoese, Joann G Lam, Kailee R Lamp, Rachael A Lyons, Justin K Nguyen, Bryce D Keyes, Jada Smith, Holly L Suther, Meaghan Swintek, Juliann C Vannordstrand, Danielle C Zacherl

Faculty, Staff and Student Publications

Introduction and establishment of non-indigenous species (NIS) has been accelerated on a global scale by climate change. NIS Magallana gigas' (formerly Crassostrea gigas') global spread over the past several decades has been linked to warming waters, specifically during summer months, raising the specter of more spread due to predicted warming. We tracked changes in density and size distribution of M. gigas in two southern California, USA bays over the decade spanning 2010-2020 using randomly placed quadrats across multiple intertidal habitats (e.g., cobble, seawalls, riprap) and documented density increases by 2.2 to 32.8 times at 7 of the 8 sites surveyed …

Environmental And Biotic Habitat Attributes Affect Rocky Intertidal Community Variability In Glacially Influenced Estuaries, Madeleine G. Mcarthur

Marine Biology

Climate change is increasing the rate of glacial recession in high latitude coastal environments. The associated increase in cold, sediment-laden freshwater into the nearshore may alter a wide array of water attributes, which will likely have ecosystem-wide impacts. One of these potential impacts is a change in typical levels of ecological community variability, which can be an indicator of stress in response to an environmental impact. Fluctuation in community composition over time is natural and can be affected by environmental conditions, as well as by the presence of habitat forming, spatially dominant organisms. The goal of this study was to …

The Economic Value Of Sea Otters And Recreational Tourism In A California Estuary, Jessica A. Fujii, Charles S. Colgan, Anthony Castelletto, Michelle M. Staedler, Amy G. Wolfrum, Kyle S. Van Houtan

Journal of Ocean and Coastal Economics

The recovery of marine megafauna can lead to improved ecosystem function and services, but not all stakeholders may benefit equally. Quantifying the local economic value of a species’ presence may appeal to broader range of stakeholders when developing conservation strategies. This study aims to examine the economic effect recreational activities can have on a local region, and to determine what role the presence of southern sea otters (Enhydra lutris nereis) had on the value visitors placed on the visit and the area’s preservation. We surveyed visitors to Elkhorn Slough, a small estuary in California known for diverse wildlife, …

Geoarchaeology Of Estuarine Seascapes In Tampa Bay, Florida., Kendal R. Jackson

USF Tampa Graduate Theses and Dissertations

This dissertation investigates the geological, ecological, and archaeological histories of Tampa Bay, Florida’s largest open-water estuary system. Previous geoscientific and archaeological work has studied the evolution of Florida’s estuaries as ‘pre-anthropogenic’ ecosystems and conceptualized Indigenous maritime societies as mostly passive inhabitants of dynamic ‘natural’ environments. Further, the environmental legacies of more recent, industrial-scale estuary modification attending Florida’s 20th-century population boom have been understudied—leading to popular and scientific confusion about historical conditions. The work composing this dissertation research seeks to reconceptualize Tampa Bay as a complex mosaic of cultural seascapes that have been variously altered and modified by human societies across …

Metal Transport In The Mixing Zone Of An Estuarine River To The Northern Gulf Of Mexico, Zhenwei Wu, Songjie He, Yi Jun Xu

Faculty Publications

To better understand the pollution potential of metals in estuaries heavily concentrated with petrochemical industries, we measured concentrations of total recoverable metals in the lower Calcasieu River in southwestern Louisiana that flows into the northern Gulf of Mexico. Water samples were collected at six sites along the last 88 km reach of the river monthly between May 2013 and November 2015, during which salinity ranged from 0.02 to 29.5 ppt from upstream to downstream. The samples were analyzed for a series of total recoverable metals, including aluminum (Al), arsenic (As), boron (B), cadmium (Cd), calcium (Ca), cobalt (Co), chromium (Cr), …

Neonate Atlantic Sharpnose Shark (Rhizoprionodon Terraenovae) Relative Abundance And Body Condition In Two South Carolina Estuaries Varying In Urbanization, Rileigh E. Hawk

Electronic Theses and Dissertations

Urbanization near estuaries has been shown to affect the growth and survival of juvenile sharks using the system as a nursery. North Inlet and Murrells Inlet, South Carolina, are similarly-sized, tidally-dominated, bar-built estuaries with extensive Sporobolus-lined tidal creeks but differ in degree of human impact. Previously, Murrells Inlet was shown to have a lower abundance and diversity of large sharks than North Inlet and Atlantic Sharpnose Sharks (Rhizoprionodon terraenovae) were shown to use North Inlet as a primary nursery. To examine potential differences in neonate shark abundance and growth between a developed estuary, Murrells Inlet, and a protected estuary, North …

Cultivating Commitment: How Cultural Ecosystem Services Affect Visitor Loyalty In Parks And Protected Areas, Thomas James Robinson

Master's Theses and Capstones

Parks and protected areas (PPAs) provide essential ecosystem services to society, including both the material and non-material benefits obtained from healthy ecosystems. While research on this topic has mainly focused on material-based ecosystem services, limited attention has been given to the benefits of non-material cultural ecosystem services (CES) such as recreation, history, and culture. Visitor loyalty refers to an individual’s commitment and willingness to return to a PPA in perpetuity and is influenced by various factors, including the quality of the recreation experience and the ecological integrity of a natural resource. CES may significantly influence visitor loyalty in PPAs, as …

Biodiversity Of Forage Fishes In The Lower Laguna Madre, Southernmost Texas, David Camarillo Jr., Elizabeth Mogus Garcia, Carlos E. Cintra-Buenrostro

School of Earth, Environmental, & Marine Sciences Faculty Publications

Coastal estuarine ecosystems serve as nursery habitats for many commercially and recreationally important fishes. Biodiversity is a structural indicator and has been used as a metric for conservation and management. In the hypersaline Lower Laguna Madre of Texas, a variety of organisms makes their living in and around the dominant seagrass vegetation. This study provides a general assessment of forage fishes biodiversity collected seasonally with bag seines in two sites: Holly Beach (HB) and South Bay (SB) within the most southern Texas bay system as part of a broader study on fish biology. A total of 15,880 fishes representing 32 …

Chlorophyll Dynamics From Sentinel-3 Using An Optimized Algorithm For Enhanced Ecological Monitoring In Complex Urban Estuarine Waters, Jonathan Sherman, Maria Tzortziou, Kyle J. Turner, Joaquim Goes, Brice Grunert

Biological, Geological, and Environmental Faculty Publications

Urban estuaries are dynamic environments that hold high ecological and economic value. Yet, their optical complexity hinders accurate satellite retrievals of important biogeochemical variables, such as chlorophyll-a (Chl-a) biomass. Approaches based on a limited number of satellite spectral bands often fail to capture seasonal transitions and sharp spatial gradients in estuarine Chl-a concentrations, inhibiting integration of satellite data into water quality monitoring and conservation programs. We propose a novel approach that utilizes the wide range of spectral information captured by the Ocean and Land Color Instrument (OLCI) to retrieve estuarine Chl-a. To validate our approach, we used measurements in Long …

The Importance Of Winter Dinoflagellate Blooms In Chesapeake Bay— A Missing Link In Bay Productivity, Nicole C. Millette, Sophie Clayton, Margaret R. Mulholland, Leah Gibala-Smith, Michael Lane

OES Faculty Publications

It is widely assumed that phytoplankton abundance and productivity decline during temperate winters because of low irradiance and temperatures. However, winter phytoplankton blooms commonly occur in temperate estuaries, but they are often undocumented because of reduced water quality monitoring in winter. The small body of in situ work that has been done on winter blooms suggests they can be of enormous consequence to ecosystems. However, because monitoring is often reduced or stopped altogether during winter, it is unclear how widespread these blooms are or how long they can last. We analyzed an over 30-year record of monthly phytoplankton monitoring samples …

An Integrative Salt Marsh Conceptual Framework For Global Comparisons, Erik S. Yando, Scott F. Jones, W. Ryan James, Denise D. Colombano, Diana I. Montemayor, Stefanie Nolte, Jacqueline L. Raw, Shelby L. Ziegler, Luzhen Chen, Daniele Daffonchio, Marco Fusi, Kerrylee Rogers, Liudmila Sergienko

Biological Sciences Faculty Publications

Salt marshes occur globally across climatic and coastal settings, providing key linkages between terrestrial and marine ecosystems. However, salt marsh science lacks a unifying conceptual framework; consequently, historically well-studied locations have been used as normative benchmarks. To allow for more effective comparisons across the diversity of salt marshes, we developed an integrative salt marsh conceptual framework. We review ecosystem-relevant drivers from global to local spatial scales, integrate these multi-scale settings into a framework, and provide guidance on applying the framework using specific variables on 11 global examples. Overall, this framework allows for appropriate comparison of study sites by accounting for …