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From Millionaires To Marsh Island: Origin And Development Of Wetland Conservation Efforts In Louisiana, Roan Guidry

Distinguished Undergraduate Researcher Program

Wetlands are protected, managed, and restored worldwide to provide a range of ecosystem services, including (i) habitat for plants and animals, (ii) carbon storage, (iii) improving downstream water quality, and (iv) reducing flooding by river and coastal waters. When did such conservation begin, and how do early conservation efforts shape recent public policy? This thesis identifies some of the earliest recorded examples of private efforts in Louisiana and analyzes how these early efforts shaped State and Federal Government action in the realm of conservation. The earliest wetland protection efforts in Louisiana began in the 1910s to sustain continental populations of …

Novel Sequential Modeling Framework Improves Phytoplankton Biomass Predictions In Response To Multiple Environmental Stressors, Zhuyin Tong, Jiayu Guo, Yikai Liu, Lizhen Lin, Jixin Chen, Xin Liu, Bangqin Huang, Edward A. Laws, Wupeng Xiao

Faculty Publications

Understanding the impacts of multiple environmental stressors on phytoplankton biomass is crucial for predicting marine ecosystem responses under global climate change. This study employed a sequential modeling framework integrating principal component analysis, generalized additive models, and artificial neural networks to improve predictions of phytoplankton chlorophyll a concentrations in the Taiwan Strait. Analyzing a decadal dataset, we found that a 2°C rise in sea surface temperature and a 0.2 pH decline will each lead to an 11.3% reduction in chlorophyll a biomass, whereas nitrogen enrichment is expected to increase it by only 2.8%. The combined effects of these stressors will result …

Nonnative Species Richness And Dominance Reveal Differing Support For Invasion Theory At A Continental Extent, Lily M. Thompson, William K. Annis, Stephen R. Midway, Julian D. Olden, Brandon K. Peoples

Faculty Publications

Aim: Empirical tests of conceptual hypotheses describing species invasions often differ depending on the spatial scale (spatial resolution and extent of study area) at which they were conducted. Some of this disparity may arise from tradeoffs in data quality necessitating the use of different indices of community invadedness among scales. Local-scale studies typically use fine-resolution, descriptive measures of community invadedness (‘dominance’, the proportion nonnative individuals) at limited spatial extents, while macroscale studies often aggregate datasets to cover large spatial extents but use coarser spatial resolution and less descriptive indices (nonnative species richness). We investigated the consequences of using different indices …

Indirect Effects And Context Dependency In Stream Fish Invasions, William K. Annis, Lily M. Thompson, Stephen R. Midway, Julian D. Olden, Brandon K. Peoples

Faculty Publications

Aim: Invasion ecology is replete with a body of well-supported yet contradictory evidence for numerous invasion hypotheses, likely as a result of context dependency. Context dependency in invasion studies can arise in two ways: (1) apparent, when results differ between studies solely due to methodical differences, or (2) mechanistic, when results truly differ due to ecological processes. One form of apparent context dependency occurs when causally linked factors associated with invasion success (hereafter, invasion drivers) either mask or enhance each other's effect on invasion success. Mechanistic context dependency can occur when regional scale processes modify the influence of local scale …

History, Annotated Gazetteer, And Bibliography Of Ornithology In Kalimantan, Indonesian Borneo, Frederick H. Sheldon, Mohammad Irham, Daisy G. S. Kho, Erik Meijaard, Subir B. Shakya, Dewi M. Prawiradilaga, Sebastianus (Bas) Van Balen

Occasional Papers of the Museum of Natural Science, Louisiana State University

Kalimantan comprises nearly three quarters of the island of Borneo and is the place where scientific study of Bornean birds began. We describe the history of bird research in Kalimantan from its beginning, highlighting the ornithologists who explored the region and how their interests and methods changed over time, from a concentration on specimen collection, to examinations of community ecology, to conservation in the face of habitat change and species depletion, to the latest investigations using satellite, genetic, and digital technology. We also highlight some future directions for research, especially the need for more work on basic ecology and biogeography. …

Macroevolution Of The Plant–Hummingbird Pollination System, Elisa Barreto, Mannfred M.A. Boehm, Ezgi Ogutcen, Stefan Abrahamczyk, Michael Kessler, Jordi Bascompte, Agnes S. Dellinger, Carolina Bello, D. Matthias Dehling, François Duchenne, Miriam Kaehler, Laura P. Lagomarsino, Lúcia G. Lohmann, María A. Maglianesi, Hélène Morlon, Nathan Muchhala, Juan Francisco Ornelas, Mathieu Perret, Nelson R. Salinas, Stacey D. Smith, Jana C. Vamosi, Isabela G. Varassin, Catherine H. Graham

Faculty Publications

Plant–hummingbird interactions are considered a classic example of coevolution, a process in which mutually dependent species influence each other's evolution. Plants depend on hummingbirds for pollination, whereas hummingbirds rely on nectar for food. As a step towards understanding coevolution, this review focuses on the macroevolutionary consequences of plant–hummingbird interactions, a relatively underexplored area in the current literature. We synthesize prior studies, illustrating the origins and dynamics of hummingbird pollination across different angiosperm clades previously pollinated by insects (mostly bees), bats, and passerine birds. In some cases, the crown age of hummingbirds pre-dates the plants they pollinate. In other cases, plant …

Spatial Roost Networks And Resource Selection Of Female Wild Turkeys, Nicholas W. Bakner, Erin E. Ulrey, Patrick H. Wightman, Nick A. Gulotta, Bret A. Collier, Michael J. Chamberlain

Faculty Publications

Wildlife demography is influenced by behavioural decisions, with sleep being a crucial avian behaviour. Avian species use roost sites to minimize thermoregulation costs, predation risk and enhance foraging efficiency. Sleep locations are often reused, forming networks within the home range. Our study, focusing on female eastern wild turkeys (Meleagris gallopavo silvestris) during the reproductive season, used social network analysis to quantify both roost site selection and network structure. We identified roost networks which were composed of a small percentage of hub roost sites connecting satellite roosts. Hub roosts were characterized by greater values of betweenness (β = 0.62, s.e. = …

Complementing Model Species With Model Clades, Makenzie E. Mabry, R. Shawn Abrahams, Ihsan A. Al-Shehbaz, William J. Baker, Simon Barak, Michael S. Barker, Russell L. Barrett, Aleksandra Beric, Samik Bhattacharya, Sarah B. Carey, Gavin C. Conant, John G. Conran, Maheshi Dassanayake, Patrick P. Edger, Jocelyn C. Hall, Yue Hao, Kasper P. Hendriks, Julian M. Hibberd, Graham J. King, Daniel J. Kliebenstein, Marcus A. Koch, Ilia J. Leitch, Frederic Lens, Martin A. Lysak, Alex C. Mcalvay, Michael T.W. Mckibben, Francesco Mercati, Richard C. Moore, Klaus Mummenhoff, Daniel J. Murphy, Lachezar A. Nikolov, Michael Pisias, Eric H. Roalson

Faculty Publications

Model species continue to underpin groundbreaking plant science research. At the same time, the phylogenetic resolution of the land plant tree of life continues to improve. The intersection of these 2 research paths creates a unique opportunity to further extend the usefulness of model species across larger taxonomic groups. Here we promote the utility of the Arabidopsis thaliana model species, especially the ability to connect its genetic and functional resources, to species across the entire Brassicales order. We focus on the utility of using genomics and phylogenomics to bridge the evolution and diversification of several traits across the Brassicales to …

Spatial Mapping Of The Benthic Community And How It Is Used To Research Effects Of Dredging In Louisiana's Lake Borgne., Meghan Johnson

LSU Master's Theses

Benthic communities are vitally important for healthy aquatic ecosystems across Louisiana’s coast. Specifically in Lake Borgne, ecologically important species of fish like the Gulf Sturgeon (Acipenser oxyrinchus desotoi) rely on benthic macrofauna as their main food source. The purpose of this study was to determine the spatial landscape of biodiversity and abundance of the benthic macrofauna community in Lake Borgne. Environmental conditions played a key role in community structure during the study period (fall 2021 through summer 2023) with a major drought occurring in 2023. In 2023, the decline in the abundance of most benthic invertebrates and in …

Quantification Of Belowground Biomass And Sediment Accretion In Mangroves Of Different Coastal Environmental Settings Of The Costa Rican Pacific Coast, Denise M. Poveda

LSU Master's Theses

The adaptation of intertidal ecosystems such as mangroves to anticipated accelerated relative sea level rise is dependent on net increase of sediment surface elevations and forest migration inland. Ecosystem models developed to simulate trajectories of ecosystem adaptations have determined that rates of soil formation are most sensitive to surface sediment (organic and inorganic) deposition and subsurface organic production by mangrove roots. Mangrove belowground biomass contributes to soil organic matter accumulation, while mangrove litter has minor contribution due to export and annual decay. In addition to belowground biomass production, inorganic sediment loading is also key contribution to soil formation and accretion. …

Local Social Capital, Disaster Housing Damage, And Mental Health: Insights From Hurricane Harvey, Ethan J. Raker, Kevin T. Smiley

Faculty Publications

Community-level social capital has been theorized to shape mental health, particularly in disaster contexts, but methodological complexities hamper prior studies. Pairing zip-code-level data on social capital from Opportunity Insights with repeated cross-sectional health survey data before and after Hurricane Harvey in Houston, Texas, we examine how local social capital moderated the mental health consequences of disaster housing damage. We first document null associations between local social capital and residents’ mental health before the disaster. Next, we fit models predicting psychological distress and poor mental health days, revealing that local levels of economic connectedness and rates of volunteering offset adverse mental …

The Influence Of Salinity And Vegetation Texture On The Ecological Roles Of Insects In Tidal Marshes In Louisiana, Benjamin G. Aker, Claudia Husseneder, Lane D. Foil

Faculty Publications

Tidal marsh insect communities are influenced by both salinity and aspects of vegetation texture (vegetation diversity, plant density, and architectural structure). These factors affect the abundances and intra- and interguild interactions of these insects and should result in broad-scale variation in the distribution and ecological functioning of tidal marsh insect communities along these gradients. However, this assumption has not been tested within Gulf Coast marshes, and the insect communities and their ecological roles are not well known. This study identifies how family-level insect biodiversity varies by salinity and which factors are most important in affecting the distribution of insect functional …

Improving Cellphone-Based Bio-Imaging Technique For Fluorescence Detection, Erteza T. Efaz

LSU Master's Theses

The research presented in this thesis focuses on the design, development, and evaluation of a fluorescence detection system. The system is implemented primarily as an Android application, Auto Camera, which leverages smartphone cameras to capture and analyze fluorescent images. The application provides a user-friendly interface with some configurable features like exposure time, ISO speed, and storage limit; as well as defining detection thresholds and setting acquisition intervals. This study begins with the architectural framework of the Android application, which is written in Java using Android Studio. The API compatibility is set to version 33, and users are prompted to grant …

Using Machine Learning To Measure Changes In Immunity Due To Climate Change In The Fall Armyworm, Spodoptera Frugiperda, Nathaniel T. Haulk

LSU Master's Theses

Object detection is a recent development that allows for the detection of multiple objects in photographs. Numerous machine learning algorithms have been developed for object detection. Here we sought to determine which algorithm performed best when relating to an organism's health and immunological response. The fall armyworm (Spodoptera frugiperda) is a major agricultural pest causing millions of dollars in damage to farmlands across the globe. With their recent spread into Africa and Asia, the need for understanding how best to control population outbreaks via biocontrol has increased. While viruses are a major biocontrol agent for controlling insect pests, we …

Regional Variation In The Trophic Ecology Of Wahoo (Acanthocybium Solandri) In The Western Atlantic Ocean, Brendan Gough, Alexandra Prouse, Michael A. Dance, R. J.David Wells, Jay R. Rooker

Faculty Publications

Intrinsic tracers, such as stable isotopes of carbon and nitrogen, are common dietary markers that accumulate in the muscle tissue of consumers and can be used to determine the dietary sources and trophic positions of consumers. The aim of this study was to assess regional variation in the trophic ecology of wahoo (Acanthocybium solandri) using bulk stable isotopes. Muscle biopsies of wahoo were collected from four regions in the western Atlantic Ocean: the eastern Gulf of Mexico, western Gulf of Mexico, Northwest Atlantic Ocean, and Caribbean Sea. Muscle tissue δ¹³C and δ¹⁵N values for wahoo ranged …

Lipid Correction For Carbon Stable Isotope Analysis Of Yellowfin Tuna, Michael A. Dance, Mitchell S. Lovell

Faculty Publications

Carbon stable isotopes (δ¹³C) are widely used in ecological studies to understand diet, food web dynamics, and movements of marine fishes. Still, δ¹³C is influenced by lipid content and often requires chemical extraction or mathematical correction. Here, we developed a species-specific mathematical lipid correction for white muscle tissue of yellowfin tuna (Thunnus albacares), a highly migratory finfish of considerable economic and ecological value. Lipid extraction was conducted on yellowfin tuna white muscle tissue (C:N range: 2.96–6.49), and both linear and non-linear lipid correction models for δ¹³C were fitted and assessed. Lipid extraction increased δ …

An Observed Increase In Cardiovascular And Respiratory-Disease Related Hospitalizations And Mortality In An Area Surrounding A Hazardous Waste Thermal Treatment Plant, Liana Isabelle Dela Torre Baconguis

LSU Master's Theses

Particulate matter (PM) pollution is highly correlated with respiratory and cardiovascular disease incidence. The generation of oxidative stress is a major way by which PM can damage the body. Environmentally persistent free radical-containing PM are generated by combustion processes and are capable of exerting increased damage on the respiratory and cardiovascular systems due to their ability to remain stable and regenerate reactive oxygen species for up to five years. Clean Harbors, LLC operates a thermal treatment plant near the city of Colfax, LA in Central Louisiana. Its regular open burning of explosives causes disturbances to the community, such as loud …

Regional Variation In Feeding Patterns Of Sheepshead (Archosargus Probatocephalus) In The Northwest Gulf Of Mexico, Elsa M. Gutierrez, Jeffrey D. Plumlee, Derek G. Bolser, Brad E. Erisman, R. J.David Wells

Faculty Publications

Feeding patterns of sheepshead, Archosargus probatocephalus, in the northwest Gulf of Mexico were examined from samples collected at two locations in Texas, USA; Galveston and Port Aransas. A total of 53 sheepshead stomachs (Galveston, n = 35; Port Aransas, n = 18) had their contents analyzed along with tissue samples from the muscle and liver for a stable isotope analysis (δ13C, δ15N, and δ34S) because they provide a contrast between short-term (liver) and long-term (muscle) measurements. Multiple species of amphipods made up the majority of the prey items in sheepshead from Galveston (%IRI = 61.79), whereas barnacles were the primary …

Ecophysiology And Genomics Of The Brackish Water Adapted Sar11 Subclade Iiia, V. Celeste Lanclos, Anna N. Rasmussen, Conner Y. Kojima, Chuankai Cheng, Michael W. Henson, Brant C. Faircloth, Christopher A. Francis, J. Cameron Thrash

Faculty Publications

The Order Pelagibacterales (SAR11) is the most abundant group of heterotrophic bacterioplankton in global oceans and comprises multiple subclades with unique spatiotemporal distributions. Subclade IIIa is the primary SAR11 group in brackish waters and shares a common ancestor with the dominant freshwater IIIb (LD12) subclade. Despite its dominance in brackish environments, subclade IIIa lacks systematic genomic or ecological studies. Here, we combine closed genomes from new IIIa isolates, new IIIa MAGS from San Francisco Bay (SFB), and 460 highly complete publicly available SAR11 genomes for the most comprehensive pangenomic study of subclade IIIa to date. Subclade IIIa represents a taxonomic …

Unhealthy Herds And The Predator–Spreader: Understanding When Predation Increases Disease Incidence And Prevalence, Robert L. Richards, Bret D. Elderd, Meghan A. Duffy

Faculty Publications

Disease ecologists now recognize the limitation behind examining host–parasite interactions in isolation: community members—especially predators—dramatically affect host–parasite dynamics. Although the initial paradigm was that predation should reduce disease in prey populations (“healthy herds hypothesis”), researchers have realized that predators sometimes increase disease in their prey. These “predator–spreaders” are now recognized as critical to disease dynamics, but empirical research on the topic remains fragmented. In a narrow sense, a “predator–spreader” would be defined as a predator that mechanically spreads parasites via feeding. However, predators affect their prey and, subsequently, disease transmission in many other ways such as altering prey population structure, …

Metagenomics And Metatranscriptomics Reveal Broadly Distributed, Active, Novel Methanotrophs In The Gulf Of Mexico Hypoxic Zone And In The Marine Water Column, Kathryn L. Howe, Kiley W. Seitz, Lauren G. Campbell, Brett J. Baker, J. Cameron Thrash, Nancy N. Rabalais, Mary Kate Rogener, Samantha B. Joye, Olivia U. Mason

Faculty Publications

The northern Gulf of Mexico (nGOM) hypoxic zone is a shallow water environment where methane, a potent greenhouse gas, fluxes from sediments to bottom water and remains trapped due to summertime stratification. When the water column is destratified, an active planktonic methanotrophic community could mitigate the efflux of methane, which accumulates to high concentrations, to the atmosphere. To investigate the possibility of such a biofilter in the nGOM hypoxic zone we performed metagenome assembly, and metagenomic and metatranscriptomic read mapping. Methane monooxygenase (pmoA) was an abundant transcript, yet few canonical methanotrophs have been reported in this environment, suggesting a role …

History, Annotated Gazetteer, And Bibliography Of Sarawak Ornithology, Frederick H. Sheldon, Dency F. Gawain, Daisy G. S. Kho, Rosalina Regai, Subir B. Shakya, Chin Aik Yeap

Occasional Papers of the Museum of Natural Science, Louisiana State University

Sarawak is Malaysia’s largest state, covering most of northern Borneo. It has a remarkable history of scientific bird study, starting in the 1840s and growing ever since. To set the stage for the gazetteer, which is the core of this paper, we start with a review of this history and discuss various forces that have influenced the direction of bird research in the state. Following this introduction comes the gazetteer, which is an annotated list of c. 865 sites in Sarawak where birds have been collected, studied, or regularly observed. The gazetteer provides the latitude, longitude, and elevation of each …

Diet And Disturbance: Seaside Sparrow Resource Use Driven By Oiling And Hurricane Isaac, Allison M. Snider, Andrea Bonisoli-Alquati, Anna A. Pérez-Umphrey, Stefan Woltmann, Philip C. Stouffer, Sabrina S. Taylor

Faculty Publications

The 2010 Deepwater Horizon (DWH) disaster led to extensive oil deposition in Louisiana’s coastal wetlands, followed two years later by Hurricane Isaac. These disturbances led to changes in saltmarsh invertebrate communities, potentially affecting higher-level predators and the saltmarsh food web. Seaside Sparrows (Ammospiza maritima) are ubiquitous, year-round residents of the coastal saltmarsh affected by the DWH spill, where they consume diverse invertebrates and may be considered an indicator species for the ecosystem’s integrity. We used DNA metabarcoding to evaluate prey consumed by Seaside Sparrows to understand how sparrows responded to residual contamination from the DWH oil spill and ecosystem disturbance …

Studies Of Roseau Cane Dieback In The Lower Mississippi River Delta Based On Remote Sensing Data Including Landsat, Worldview, And Drone, Nan Shang

LSU Doctoral Dissertations

This research focused on the Roseau cane (Phragmites australis) dieback assessment in the lower MRD of Louisiana and introduced a comprehensive and systematic multi-source remote sensing method for assessing wetland and Roseau cane dieback and habitat dynamics analysis from three scale levels from large-scale to small scale.

Large-scale historical vegetation/land change analyses were conducted in the lower MRD based on Landsat in the past two decades (2001 - 2021). A strong increasing trend of vegetation was found since 2005. Around 51 km² ofdieback area was detected which accounts for 11% of the overall vegetation coverage. This research …

Economic Freedom, Climate Culpability, And Physical Activity Indicators Among Children And Adolescents: Report Card Grades From The Global Matrix 4.0, Eun Young Lee, Patrick Abi Nader, Salomé Aubert, Silvia A. González, Peter T. Katzmarzyk, Asaduzzaman Khan, Wendy Y. Huang, Taru Manyanga, Shawnda Morrison, Diego Augusto Santos Silva, Mark S. Tremblay

Population and Public Health Science Faculty Publications

Background: Macrolevel factors such as economic and climate factors can be associated with physical activity indicators. This study explored patterns and relationships between economic freedom, climate culpability, and Report Card grades on physical activity-related indicators among 57 countries/jurisdictions participating in the Global Matrix 4.0. Methods: Participating countries/ jurisdictions provided Report Card grades on 10 common indicators. Information on economic freedom and climatic factors were gathered from public data sources. Correlations between the key variables were provided by income groups (ie, low- and middle-income countries/jurisdictions and high-income countries/jurisdictions [HIC]). Results: HIC were more economically neoliberal and more responsible for climate change …

Are Existing Modeling Tools Useful To Evaluate Outcomes In Mangrove Restoration And Rehabilitation Projects? A Minireview, Victor H. Rivera-Monroy, Xiaochen Zhao, Hongqing Wang, Zuo George Xue

Faculty Publications

Ecosystem modeling is a critical process for understanding complex systems at spatiotemporal scales needed to conserve, manage, and restore ecosystem services (ESs). Although mangrove wetlands are sources of ESs worth billions of dollars, there is a lack of modeling tools. This is reflected in our lack of understanding of mangroves’ functional and structural attributes. Here, we discuss the “state of the art” of mangrove models used in the planning and monitoring of R/R projects during the last 30 years. The main objectives were to characterize the most frequent modeling approach, their spatiotemporal resolution, and their current utility/application in management decisions. …

Development And Structural Organization Of Mexico’S Mangrove Monitoring System (Smmm) As A Foundation For Conservation And Restoration Initiatives: A Hierarchical Approach, María Teresa Rodríguez-Zúñiga, Carlos Troche-Souza, María Isabel Cruz-López, Victor H. Rivera-Monroy

Faculty Publications

Mangroves provide ecosystem services worth billions of dollars worldwide. Although countries with extensive mangrove areas implemented management and conservation programs since the 1980s, the global area is still decreasing. To recuperate this lost area, both restoration and rehabilitation (R/R) projects have been implemented but with limited success, especially at spatial scales needed to restore functional properties. Monitoring mangroves at different spatial scales in the long term (decades) is critical to detect potential threats and select cost-effective management criteria and performance measures to improve R/R program success. Here, we analyze the origin, development, implementation, and outcomes of a country-level mangrove monitoring …

The Effect Of Channel Stability On Fish Condition And Diet In Thompson Creek, La, Alexia Lagrone

Honors Capstones

No abstract provided.

Current Methods And Future Directions In Avian Diet Analysis, Brandon D. Hoenig, Allison M. Snider, Anna M. Forsman, Keith A. Hobson, Steven C. Latta, Eliot T. Miller, Michael J. Polito, Luke L. Powell, Samantha L. Rogers, Thomas W. Sherry, David P.L. Toews, Andreanna J. Welch, Sabrina S. Taylor, Brady A. Porter

Faculty Publications

Identifying the composition of avian diets is a critical step in characterizing the roles of birds within ecosystems. However, because birds are a diverse taxonomic group with equally diverse dietary habits, gaining an accurate and thorough understanding of avian diet can be difficult. In addition to overcoming the inherent difficulties of studying birds, the field is advancing rapidly, and researchers are challenged with a myriad of methods to study avian diet, a task that has only become more difficult with the introduction of laboratory techniques to dietary studies. Because methodology drives inference, it is important that researchers are aware of …

Responses Of Wetland Soil Microbial Communities To Different Types Of Anthropogenic Stress, Grace Ann Cagle

LSU Doctoral Dissertations

Microorganisms are the major drivers of biogeochemical transformations of carbon and nitrogen in wetlands. These processes are crucial for ecological sustainability and are heavily impacted by human activities. How anthropogenic stress affects the microbial drivers of carbon storage and nutrient cycling in wetlands is not well understood. I investigated the response of wetland soil microbial communities to three different types of anthropogenic stress using DNA sequencing. First, I studied the effect of warming on microbial carbon processing in a peatland underlaid by permafrost by comparing the abundances of specific genes between sites subjected to five years of warming and controls. …