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Anthropogenic Impacts Lead To Plant Biodiversity Losses In A Unique And Fragile Coastal Dune Ecosystem, Natalie Clagett

Theses

At the southern end of the California Floristic Province lie the El Socorro Dunes. These Dunes have the highest biodiversity of any dune system in Mexico, hosting at least 11 perennial endemic and rare plant species. The El Socorro Dunes’ perennial vegetation was surveyed between 2008 to 2010, but since then these dunes have faced pressure from regional land transformations, such as off-roading and mining, invasive species spread, and climate change. This study examines the plant community changes within the El Socorro Dunes and potential links to stressors. Our results show significant losses of native plants, and significant increases in …

Greening The Edge: Investigating Riparian Buffer Restorations In A Pastoral Setting And Their Effects On Soil Carbon And Microbial Community Composition., Seth Mccullough

Masters Theses, 2020-current

Riparian buffer restoration represents a critical strategy for enhancing ecosystem health and resilience in agricultural landscapes. This study investigates the effects of riparian buffer restoration on soil properties, microbial communities, and carbon dynamics in Rockingham County, VA. Through a comprehensive field study, we assessed the physicochemical properties of soil, microbial biomass, community composition, and soil carbon storage in restored and unrestored riparian buffers. Our findings reveal significant improvements in soil physical properties in restored buffers, including increased soil moisture (p < 0.05) and decreased bulk density (p < 0.01), indicating enhanced soil structure and water retention capacity. While no significant differences were detected in soil pH or cation exchange capacity, restored buffers exhibited higher soil carbon stocks (p < 0.05) and carbon-to-nitrogen ratios, suggesting potential differences in nutrient cycling processes and organic matter decomposition rates. Moreover, restored buffers showed increased microbial biomass (p < 0.01), potentially driven by improved habitat conditions and shifts towards a fungal-dominated microbial community.

Although no significant differences were found in overall microbial community composition between restored and unrestored sites, specific shifts in bacterial …

Ancient Wisdom, Modern Prosperity: Harnessing Traditional Ecological Knowledge To Revitalize Australia's Economy, Environment, And Human Wellbeing, Annabelle L. Baulch

Student Theses 2015-Present

This paper explores the traditional knowledge of Australia’s Indigenous people and how it can improve Australia's environment, health, and economic prosperity to shape a more sustainable future. Indigenous Australians managed the land for thousands of years; however, being forced off the land following European colonization resulted in terrible cultural, social, and environmental disruption for Aboriginal Australians and made conservation efforts difficult. Wildfires, imported species, mining, and agriculture is steadily destroying the Australian ecosystem, contributing to climate change, species extinction, and gaps in our cultural and ancestral knowledge. Chapter One overviews Australia's environmental issues; it uses quantitative data to explore the …

Crossing The Ocean: The Importance Of Gene Flow In Island Evolution, Ethan F. Gyllenhaal

Biology ETDs

Islands have long been a critical arena for the development of ecological and evolutionary theory, particular due to persistent open-water gaps between them. In this dissertation I demonstrates how these caps are permeable, which can be leveraged to understand evolution on islands and more broadly. The first chapter develops this connection between ongoing, overwater gene flow and island biogeographic theory, and tests it on an archipelago species. The second take a three-pronged approach in demonstrating how over-water gene flow can bias phylogenetic inference, and how many phylogeographic metrics in islands are likely shaped by long-term gene flow. The final two …

Fecal Genomics Provides Insights On Connectivity Of Endangered Wildlife In A Human Dominated Landscape, Abhinav Tyagi

Theses and Dissertations

Many mammalian species, facing severe historic range reductions, now inhabit fragmented habitats. Habitat fragmentation involves the reduction of habitat into smaller patches, increasing distances between them, and eventually leading to small isolated populations. Species' responses to habitat alteration may vary based on factors such as body size, dispersal ability, and abundance. Understanding these differences is crucial for effective multispecies conservation planning. Genomic data, within a landscape genetic framework, are increasingly applied to evaluate the effects of habitat fragmentation and understand influential landscape features for connectivity. The quantity of data enhances the power and precision of assessing landscape impacts on gene …

Lmpact Of Salmonella Enterica Effector Proteins On Plant Physiology And Immunity, Sara Qader

Honors Theses

Salmonella enterica serovar Typhimurium are primarily recognized as pathogens associated with foodborne illnesses in humans. Salmonella also can colonize plant tissue effectively. The pathogen relies on type III secretion systems (T3SS) to infect mammals and plants successfully and counteract the immune response. Understanding the molecular mechanisms underlying Salmonella’s interactions with plants is essential for developing effective strategies to reduce its impact on human health and agriculture. Effector proteins, known for their role in modulating host-pathogen interactions, have been implicated in the virulence and pathogenicity of Salmonella. However, their specific functions and contributions to Salmonella’s interactions with plants remain largely unknown. …

Beating The Heat: The Use Of Coral-Benefitting Bacteria For Heat-Stressed Anemones And Inspiring Future Biologists, Navah Eshraghi

Undergraduate Honors Theses

The warming of ocean temperatures has caused mass coral-bleaching events characterized by the expulsion of vital algal symbionts from coral tissues. However, the possibility of algal reuptake and existence of bacteria that support coral-algal symbiosis are two avenues of potential restoration efforts. Using the sea anemone Exaiptasia diaphana as a model for corals, I tested whether the coral-benefitting bacterium Endozoicomonas montiporae could enhance algal uptake under ambient (27°C) and heat-stressed (32°C) conditions. I then turned acquired results into an article modeled after National Geographic Kids to introduce the experiment to younger ages. While temperature was a larger determinant of algal-uptake …

Three Additions To The False Click Beetle (Coleoptera: Elateroidea: Eucnemidae) Fauna In The Nearctic Region, Robert L. Otto

Insecta Mundi

Three species of false click beetles (Coleoptera: Eucnemidae) are added to the Nearctic fauna. One new species, Isorhipis bicolor, is described from a small series collected in Florida, U.S.A. Eighteen specimens collected from Georgia were identified as Dyscharachthis amplicollis (Fleutiaux), new U.S.A. records for a species previously taken from Japan and Southeast Asia. Examination of a series of eucnemids collected by Kyle Schnepp in Florida allowed me to revisit the Deltometopus fauna in eastern North America. Antennal structures present in a series of male specimens in the loan and past examined specimens are definitive enough to resurrect Deltometopus …

First Record Of The Beekeeping Pest Aethina Tumida Murray (Coleoptera: Nitidulidae) For Honduras, Jesus Orozco

Insecta Mundi

Aethina tumida Murray (Coleoptera: Nitidulidae) (also known as the small hive beetle), an important pest in apiaries, is reported from Honduras for the first time, new country record. The precise distribution in the country is unknown, and no damage related to it has been observed. Photographs are provided to aid in its identification. Differentiation of A. tumida from Aethina villosa Reitter and Aethina quadrata Sharp, which also occur in Honduras, is provided.

ZooBank registration. urn:lsid:zoobank.org:pub:DAF12C6A-0F8C-4151-9C4D-F191CCC4032F

The First Draft Genome Of Cold-Water Octocoral Anthothela Grandiflora, The Great Flowerbud Coral, Laurel Humphrey

Honors Scholar Theses

Cold-water corals are important sources of ocean biodiversity, yet populations are increasingly threatened by human activity and climate change. Soft octocorals may endure higher ocean acidification levels in comparison to stony hexacorals, although the mechanisms of octocoral biomineralization are less understood. Building genomic resources for cold-water octocorals could help to close information gaps by elucidating the evolutionary history of octocoral calcification and provide a reference for future studies of adaptation to acidified waters. This report describes the first reference genome for the cold-water octocoral species Anthothela grandiflora found throughout the Atlantic Ocean. Sequencing using Oxford Nanopore Technologies generated 43.6 Gb …

New Records Of Mesobuthus Rakhshanii Barahoei, 2022 In Iran (Scorpiones: Buthidae), Ersen A. Yağmur, Zhale Baghernavesi, Zahra Taherkhani, Parsa Akbari, Mohammad Moradi

Euscorpius

Mesobuthus rakhshanii Barahoei, 2022 (Scorpiones: Buthidae) was so far known only from the type locality in Sistan and Baluchestan Province, Iran. We give a list of numerous new records of this species from the same province. A map and detailed illustrations are provided.

Fiddler Crab Gut Microbiomes As An Indicator For Eutrophication Due To Waste-Water Contamination In Estuaries, Madison L. Geraci

Honors Theses

Estuaries are unique biogeochemical zones in coastal systems that provide a myriad of ecological functions: providing habitat for critically important fishery species, diverse species of plants and animals, and contributing to nutrient cycling. Estuaries are vulnerable to anthropogenic stressors as they are intersections between marine and terrestrial communities and are often the hotspot of coastal development and activity. Estuarine sediments act as repositories for anthropogenic contaminants, including excess nutrient runoffs and waste-water pollution that can cause states of eutrophication. Microorganisms are sensitive to these environmental changes, presenting a unique opportunity of being useful bioindicators of environmental stress. Isolating microorganisms from …

Impacts Of Urbanization On Demographics And The Stress Level Of White-Tailed Deer In The Piedmont Of South Carolina, Cameron Bramhall

Graduate Theses

Population demographics and density studies are a common way of determining number of individuals in location. Understanding how many individuals and sex ratios can help estimate total populations for future potential management practices. For white-tailed deer (Odocoileus virginianus), commonly referred to as whitetail deer, like other cervids, having too many or too few individuals in an area can cause issues. Some of the issues that may arise with too many individuals include higher disease potential, and a general lack of resources leading to an increase in competition. As areas that were once habitat for whitetail deer become more and more …

Threads Of Connection: An Offering To Re-Tangle Humanity And Nature With The Patterns Of Our World, Emily Shelton

Graduate Theses

In our world there are patterns of self-similarity that serve as evidence of the interconnectedness between humankind and the rest of the natural world. They are reflected in our bodies, behaviors, and environments, both natural and manmade, and can be found throughout systems at every scale, micro through macro. These organic, linear motifs branch into smaller iterations that seem to shape our existence on this planet as we gravitate towards experiences that echo these patterns. During everyday acts like shopping in a grocery store or a crowd at a concert, we unconsciously participate in self-similar collective movements as we navigate …

West Coast Rock Lobster Resource Harvest Strategy, Department Of Primary Industries And Regional Development, Western Australia

Fisheries Management Papers

Harvest strategies for Western Australia’s (WA) aquatic resources are formal documents developed by the Department of Primary Industries and Regional Development (DPIRD, the Department) to support decision-making processes that ensure the outcomes are consistent with the principles of Ecologically Sustainable Development (ESD; Fletcher 2002a) and Ecosystem Based Fisheries Management (EBFM; Fletcher et al. 2012). Harvest strategies are a key component of all contemporary fishery management systems and a requirement for certification under the Marine Stewardship Council (MSC). The objectives of ESD are reflected in the objectives of the Fish Resources Management Act 1994 (FRMA) and the Aquatic Resources Management Act …

Do American Bison Practice Democracy? Group Consensus Decision Making Drives Bison Herd Movements And Cohesion., Matthew Sapien

Electronic Theses and Dissertations

The American bison is an iconic mammal that lives in large social herds and is considered a threatened species. Little is known about how bison make decisions as a group, whether through despotic individuals or group consensus. In this dissertation, I researched the mechanisms bison use to make herd movement decisions in 3 herds in the United States. In chapter one I examined the number of bison that participated in voting events for herd movement decisions and whether the final movement decision matched the direction with the most votes. Bison herd movements did match the direction with the most adult …

Reconnecting With Nature One Classroom At A Time, Bianca Apuzzo

Senior Honors Projects

Environmental science is more important to today’s society than it has ever been, and developing basic ecoliteracy is the easiest way we can work towards a more sustainable future. Ecoliteracy allows us to connect deeper to nature and provides us with the information needed to protect and restore our beautiful planet. We are rolling downhill, picking up speed as we go, through a silent mass extinction. The scariest part of it all: nobody seems to care.

In response to the lack of environmental education provided to today’s students, I have created a syllabus for a high school level science course …

Invasive Shrubs Differentially Alter Autumnal Activity For Three Common Small-Mammal Species, Brian M. Connolly, Chad Zirbel, Carson Keller, Mark Fuka, John L. Orrock

Biology Faculty Scholarship

Seasonal variation in animal activity influences fitness and the intensity of ecological interactions (e.g., competition, predation), yet aspects of global change in the Anthropocene may catalyze shifts in seasonal activity. Invasive plants are components of global change and can modify animal daily activity, but their influence on animal seasonal activity is less understood. We examined how invasive woody shrubs (Autumn olive [Elaeagnus umbellata] and Amur honeysuckle [Lonicera maackii]) affect seasonal activity of three common small-mammal species by coupling experimental shrub removal with autumnal camera trapping for two consecutive years at six paired forest sites (total 12 …

The Causes And Consequences Of Behavioral Plasticity In Anti-Predatory Defense And Mate Choice In Tropical Butterflies, Sushant Potdar

Graduate Theses and Dissertations

Behavioral plasticity, where individuals change their behaviors in response to varying environmental and social conditions, affects major evolutionary trajectories. But how individuals change these behaviors under certain social situations, and what the genetic causes and consequences of such behavioral changes are in response to social environments are yet to be fully understood. I address these questions in the context of anti-predatory behaviors (chapter 1), and mate choice (chapters 2, 3, 4) in tropical butterflies. In the context of anti-predatory behaviors, I found predator-specific behavioral changes in toxic Heliconius butterflies, suggesting variance in predation pressures and butterfly recognition of bird calls. …

Assessing Health Implications Of Monarch Butterfly Populations And Behaviors, Kira Goldman, Kelsey E. Fisher Dr.

Honors Scholar Theses

Pollinator populations have seen massive declines over the past decade due to anthropogenic activity and climate change posing serious threats to the health of humans and ecosystems (Ulyshen & Horn, 2023). As agents responsible for the production of about 35% of micronutrient rich food crops necessary for adequate nutrition to lead healthful lives and prevent nutrition associated diseases, pollinator decline is a public health concern (Aizen et al., 2009). Monarch butterflies (Danaus plexippus) serve as bio indicators for the health of pollinator populations because of their analogous habitat and food resources shared with many other pollinator species, including bees and …

The Influence Of Researcher Disturbance On Raccoon Predation Of American Alligator Nests, Clarissa Tuten

Electronic Theses and Dissertations

Raccoons (Procyon lotor) are a dominant predator of American alligator (Alligator mississippiensis) nests in the southeastern United States, using a combination of olfactory, visual, and tactile cues to identify nest locations. Studies on alligator nesting ecology typically require researchers to create paths through marsh habitat, potentially introducing visual and olfactory cues raccoons may use to locate nests. The purpose of this study was to evaluate the effect of human visitation to alligator nests on the frequency of raccoon nest predation at two sites in coastal South Carolina, Tom Yawkey Wildlife Center (TYWC) and Santee Coastal Reserve (SCR). We hypothesized that …

Vibratory Noise Impacts The Sensory Ecology Of A Funnel-Weaving Spider, Brandi June Pessman

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Animals experience their world through diverse sensory systems, leveraging information from prey, predators, and potential mates to inform behavioral decisions. Environmental noise disrupts information via spectral or amplitude masking, degradation, or distortion, potentially leading to costly errors in responses. Critically, urbanization has accelerated the proliferation of novel noise sources, triggering significant shifts in communication, foraging, and predator-prey dynamics among urban wildlife. While vertebrate studies have illuminated urban animals’ flexibility to anthropogenic acoustic noise, a comprehensive understanding requires broader investigations across diverse animal taxa and sensory modalities. To address these gaps, my dissertation explored the impacts of anthropogenic substrate-borne (vibratory) noise …

Analyzing Phototaxis And Related Visual Behaviors Among Diverse Species Of Drosophila, Madeline M. Hill

Honors Program: Senior Projects (Public)

Phototaxis and related visual behaviors can vary between species, and thus members of the genus Drosophila make an excellent study system to examine the evolution of vision. While some existing research points to these phototactic behaviors arising due to mating requirements or due to their species-specific ecology or environmental factors, there exists a lack of understanding as to why striking behavioral differences can exist between closely related species, or between members belonging to the same genus. The present research seeks to uncover the specifics regarding these discrepancies in visual evolution and aims to provide a foundation of knowledge about visual …

Do Heat Waves Drive Natural Selection In Damselflies?, Adam Baranyk

Biological Sciences Undergraduate Honors Theses

Climate change has led to changes in both mean temperatures and temperature extremes over the recent years. These changes have had differential effects on animals throughout the world. Ectotherms depend on their external environment for thermal regulation, making them especially susceptible to temperature extremes. It is not yet clear whether there is a relationship between physical traits in ectotherms, and survivorship throughout a heat wave. That is, whether or not temperature extremes driven survival selection. In this study, a heat wave was simulated artificially using thermally regulated mesocosms at different temperatures (18°C, 22° C, 26° C, 30° C) with a …

Identifying Grassland Cores In The Southeast: Relating Spatial Covariance To Avian Communities And Vegetation Structure, Lauren L. Berry

Graduate Theses and Dissertations

Globally, grasslands are declining in range, which is leading to a decline in grassland-dependent taxa. These declines can be attributed to a variety of issues, a major one being the encroachment of woody species into historic grasslands. There is a new framework for strategizing grassland management, referred to as “Defend the Core,” which calls for proactive management of intact grasslands, meaning conserving remaining grasslands by preventing woody encroachment in the first place. To successfully defend the core, it is imperative that we develop rapid methods to identify intact grassland cores for management priority. One method that can be used for …

Plant-Plant Interaction In Early- Vs. Late-Successional Varieties Of The Hawaiian Landscape-Dominant Tree, Metrosideros Polymorpha, Tomoko Sakishima

UNLV Theses, Dissertations, Professional Papers, and Capstones

Plant-plant interactions play an important role in assembling plant communities. Interactions between neighboring plants can vary as a result of the genetic relatedness of neighbors, impacting rates of growth and patterns of resource allocation. When growing alongside close relatives, some species decrease their growth in a form of cooperation, while others grow faster through facilitation. A complication of plant interaction studies arises because decreased growth in the presence of close relatives can also be due to competition for resources, which increases with phenotypic similarity. Further complicating matters, mycorrhizal fungi, through their connections with plant roots, may strongly influence plant interactions. …

Causes And Consequences Of Space-Use Behavior Under Predation Risk In A Free-Living System, Brian J. Smith

All Graduate Theses and Dissertations, Fall 2023 to Present

Predators can have important ecological effects through killing and eating their prey, the so-called consumptive effect, but predators can also have a nonconsumptive effect (NCE) on their prey – this happens when the risk of predation itself causes prey to alter their behaviors or other traits and these alterations ultimately reduce prey survival, reproduction, or population size. While scientists understand the consumptive effects of predators well, we are still unsure whether NCEs are important in free-living systems. In this dissertation, I sought to better understand the potential NCEs of predators (wolves and cougars) on elk in northern Yellowstone National Park …

Movement Behavior And Habitat Selection Of Juvenile Mountain Lions (Puma Concolor) During Three Behavioral States Of Dispersal, John F. Randolph

All Graduate Theses and Dissertations, Fall 2023 to Present

Juvenile dispersal, the act of moving from their natal range to the place where they eventually reproduce and establish an adult home range is hazardous. Juveniles must travel and find food across unfamiliar landscapes, where they must also cross roads, avoid harvest, and navigate developed landscapes. Despite the inherent dangers of dispersal, this demographic process is important for finding suitable mates and reducing inbreeding depression. Wildlife conservation concerns arise when individuals are unable to disperse due to a loss of connectivity, as this can negatively impact population demographics and genetic diversity. We explored the effects of hunting and human-developed landscapes …

Survey Of The Bolctes From Fish River Nature Preserve, Noah T. Nelson

Honors Theses

Boletes are a special kind of mushroom inside of the Kingdom Fungi that are distinguished from other mushrooms by their uniquely pored hymenium, as opposed to gills. Many boletes are ectomycorrhizal, meaning they are mutualists with vascular plants, and thus beneficial to the overall health of the terrestrial ecosystem. Some are well-known for their edibility and are of economic importance. In the United States 59 genus-level clades comprising 290 operational taxonomic units have been reported. The southeastern US and Gulf Coast regions however are less researched and recorded for their mushroom ecology. In Alabama, only 56 bolete species have been …

Evaluating Novel Approaches For Improving Anadromous Fish Passage In Coastal Rivers, Aaron Bunch

All Dissertations

Few of the world's rivers remain free-flowing for over 1000 km, significantly impacting anadromous fish populations due to dam-induced habitat fragmentation. Three partial migration barriers (low-head dams) on North Carolina's Cape Fear River (USA)—lock and dam 1 (LD1), lock and dam 2 (LD2), and lock and dam 3 (LD3)—impact American shad Alosa sapidissima, Atlantic sturgeon Acipenser oxyrinchus oxyrinchus, and striped bass Morone saxatilis populations. Mitigation strategies to pass fish upstream have included conservation locking, nature-like fishway construction, and environmental flows (e-flows). This study introduced a novel e-flow (dam submergence flow), tested acoustic double-tagging techniques for tracking American …