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Reconstructing Stand-Age Structure In A Wet Miombo Woodland Using Dendrochronology, Zambia, Clara Tiyembekeze Zulu

All-Inclusive List of Electronic Theses and Dissertations

Dendrochronological research in tropical Africa has remained limited, leaving critical gaps in stand-age structure and climate-growth relationships in seasonally dry tropical woodlands. This study reconstructed stand-age structure and assessed climate sensitivity in the wet Miombo woodland of African Explosives Limited (AEL) forest, Copperbelt Province, Zambia. Field sampling was conducted during four African Dendrochronology Fieldschools (2021-2024) using a Modified Variable Area Transect (MVAT) design across nine plots. The series intercorrelation was 0.351; the average mean sensitivity was 0.423. The oldest tree was 170 years old, and more than 70% of the sampled species showed potential for dendrochronology. Markhamia obtusifolia was the …

Reconstruction Of Copepod Populations In Sierra Nevada Lakes Using The Diatom Fragilaria Cyclopum, Rorie Reisner

All-Inclusive List of Electronic Theses and Dissertations

Copepods are one of the most abundant types of zooplankton, and their populations are often a vital part of the food chain, but their past populations cannot be estimated from lake sediments because their exoskeleton usually does not fossilize. Gull Lake is a glacial lake located in the subalpine region of the Sierra Nevada, California, which stands out due to the presence of the diatom Fragilaria cyclopum, which is rarer in diatom assemblages. Fragilaria cyclopum exclusively grows on copepods in lakes. Diatoms have an opaline silica skeleton that often fossilizes in lake sediments, so we can use this relationship with …

A Comparison Of Ahdrift And Pitfall Traps For Surveying Small Vertebrates, Gabrielle Risko

All-Inclusive List of Electronic Theses and Dissertations

Understanding species occupancy is necessary to inform wildlife management and conservation decisions. To minimize the invasiveness of occupancy studies, some wildlife researchers have deployed game cameras to detect the presence of small vertebrates instead of utilizing stressful traditional live-capture methods. The Adapted Hunt Drift Fence Technique (AHDriFT) is an increasingly popular method for modifying and deploying camera traps to detect small vertebrates; however, no studies have directly compared AHDriFT to traditional pitfall traps operating at the exact same time, even though both are deployed along drift fences to capture small vertebrates. I compared these two methods (pitfall trapping and AHDriFT …

Determining The Role Of Maumee River Sediments In Microbial Nitrogen Transformations And Net Fluxes, Ashlyn Stanalonis

Master's Theses

The Maumee River watershed is the largest of any river feeding into the Laurentian Great Lakes and is primarily comprised of agricultural land uses. Most cultivated crops require fertilizer applications to sustain growth and productivity. Fertilizer runoff is a major source of nutrient loading to the river, and total nitrogen (N) and phosphorus (P) inputs contribute to eutrophication and cyanobacterial blooms in the western basin of Lake Erie. This study aimed to characterize Maumee River sediments as net N sinks or sources to the western basin and evaluate N removal efficiency (a valuable ecosystem service) to determine if river sediments …

Eusocial Caste Specialization Under Abiotic And Biotic Stress In A Stingless Bee, Tetragonisca Angustula, Kristin M. Robinson

Dissertations

Eusocial insects rely on division of labor to achieve high colony efficiency and provide essential ecosystem services, but specialization may also constrain colony resilience when workers operate near their physiological or behavioral limits under abiotic and biotic stressors. How specialization mediates these responses remains poorly understood, particularly in stingless bees (Tribe: Meliponini). Using the agriculturally relevant stingless bee Tetragonisca angustula, which possesses a specialized soldier subcaste, I investigated how a high degree of worker specialization influences physiological tolerance and predator responses across worker subcastes.

In this dissertation, I quantified variation in thermal tolerance and desiccation resistance among worker subcastes …

Lizards In The Trees: Structural, Functional, And Behavioral Specializations To A High-Risk Environment, Victor D. Munteanu

All Dissertations

Animals must contend with unexpected changes in their habitat and environment to thrive. Arboreal habitats can consist of a wide variety of environmental features, and failure to adequately contend with these features can result in high risk of injury or death upon falling. Despite these strong selective pressures, many vertebrate lineages have successfully invaded arboreal habitats. Using lizard taxa as a model system, I investigated how morphology and behavior have evolved within this specific habitat transition. I pursued these investigations through complementary analyses including: 1) evaluating the effect of stance height and tail prehensility on perturbation recovery, 2) assessing behavior …

Prenatal Acoustic Programming Of The Developing Hypothalamus: A Multi-Omic Analysis Of Heat Call Exposure In Zebra Finch Embryos, Prakrit Subba

All Dissertations

Climate change is intensifying thermal stress on wildlife globally, yet the developmental mechanisms by which embryos use prenatal cues to adjust to predicted environments remain unclear. In Australian zebra finches (Taeniopygia guttata), incubating parents produce distinctive heat call vocalizations at high ambient temperatures, and embryos exposed to these calls during late incubation develop altered growth trajectories, thermoregulatory capacity, and reproductive outcomes, suggesting a form of anticipatory developmental programming triggered by sound alone. To investigate the molecular basis of this response, I initially hypothesized that prenatal heat call exposure would act primarily through hypothalamic neuroendocrine reprogramming, given the central …

Effects Of Urbanization On Barrier Island Bobcats, Meghan P. Keating

All Dissertations

Urbanization is a leading driver of ecological change and presents unique challenges for carnivores by altering habitat availability, prey communities, and exposure to anthropogenic threats. Although many carnivore species persist in developed landscapes, the ecological and demographic consequences of urbanization often remain poorly understood, particularly over long timescales. Using one of the longest-running studies of a free-ranging carnivore population, I evaluated the effects of urbanization on the behavior, resource use, exposure risk, and population dynamics of bobcats (Lynx rufus) inhabiting a residentially developed barrier island in coastal South Carolina, USA. I first examined temporal and spatial responses to …

Alfred Russel Wallace Notes 42: How Accurate Are The Transcriptions Presented At The Alfred Russel Wallace Page Website?, Charles H. Smith

Faculty/Staff Personal Papers

A look is taken at the level of accuracy displayed by the transcriptions of Wallace writings offered at the Alfred Russel Wallace Page website, as determined by a ChatGPT analysis.

A Geometric Morphometric Analysis Of Acetabular Shape Variation Across Bat Families, Jordan L. Huff

Electronic Theses and Dissertations

Bats are the only mammals capable of powered flight, and research is concentrated on this adaptation. Their non-flight locomotion has received comparatively little attention. Previous studies show that non-flight locomotor behaviors vary across families. Members of Pteropodidae are efficient climbers but cannot effectively walk, whereas Phyllostomidae and Vespertilionidae are better at terrestrial locomotion but show reduced arboreal capabilities. The non-flight locomotion of Hipposideridae and Rhinolophidae is less understood, although rhinolophids exhibit limited terrestrial locomotion. This study examined whether differences in locomotor behavior are associated with variation in acetabular morphology. A geometric morphometric analysis of acetabular shape was conducted across multiple …

The Past, Present, And Future Of Climate Adaptation In A Widespread Lizard Species, Matthew R. Mcternan

All Dissertations

Climate, as a selective force, shapes patterns of biodiversity globally. However, how species adapt to climate remains a central question of biology. The need to understand climate adaptation is paramount, as global climate change threatens a large portion of global diversity. Climate can impose selection on life by either controlling rates of energy intake and expenditure through effects on body temperature and activity, or by exposing organisms to conditions beyond their physiological limits. Studies of climate adaptation have identified a wide-range of putatively adaptive phenotypic patterns, but genomic evidence is increasingly being used to investigate these patterns and better understand …

Silviculture For Coastal Forest Resilience: Promoting Forest Regeneration And Managing Invasive Plant Species, Ryan Bohannon

All Dissertations

Coastal forests of the southern United States and the ecosystem services they provide are threatened by an intensifying and interacting suite of disturbances associated with global change. Silvicultural strategies such as enrichment planting, invasive plant management, and browse mitigation treatments can enhance the resilience and adaptive capacity of forests to these threats by promoting sustainable regeneration and recruitment dynamics. To improve our understanding of coastal forest disturbance regimes and their impacts on forest stand dynamics, I conducted a systematic literature review of maritime forest disturbance ecology and identified coastal storms, ungulate browsing pressure, and invasive plants as primary disturbances shaping …

'Fast' And 'Slow' Water Handling Strategies Explain Pinyon Pine Decline And Juniper Expansion, M. Faraz Rehman

All Graduate Theses and Dissertations, Fall 2023 to Present

Across the western United States, pinyon and juniper woodlands are changing with pinyon pine trees dying back while juniper becoming more abundant. Previous studies suggested that pinyon may lose more water during drier periods. But water loss is only part of the story. Water inputs, or how plants absorb water, are also likely to be important, but rarely well understood. To better understand this, we measured how pinyon and juniper absorb water from different soil depths and how actively they lose water through their leaves. Measurements were made over two years at three sites that ranged from more dry to …

An Analysis Of Mating Strategies In Rotifers Inhabiting Temporary Habitats, Ariel Bollinger

Open Access Theses & Dissertations

Reproduction is critical for organisms inhabiting ephemeral aquatic habitats where desiccation risk favors rapid and successful mating. Monogonont rotifers rely on sexual reproduction to produce diapausing eggs that withstand harsh conditions. I investigated how mating behaviors vary among populations of five rotifer species based on the hydroperiod of their habitat: Epiphanes brachionus and E. chihuahuaensis were sampled from habitats with short (SH) and long (LH) hydroperiods; Euchlanis dilatata was collected from a short (SH) and a permanent habitat; and Plationus patulus and Sinantherina socialis were collected from a long (LH) and a permanent (Perm) habitat. I hypothesized that SH populations …

Land Condition Standards For The Western Australian Nullarbor Pastoral Region, Peter-Jon A. Waddell, Wayne J. Fletcher

Natural resources published reports

This report outlines the quantitative land condition standards that define acceptable pastoral land condition for the Western Australian part of the Nullarbor, to meet the regulatory requirements of the Land Administration Act 1997 and the Soil and Land Conservation Act 1945.

The Department of Primary Industries and Regional Development is developing regional-level pastoral land condition standards for Western Australia as a critical component of the Framework for sustainable pastoral management – revised edition (Fletcher 2022), the purpose of which is to address the Office of the Auditor General’s recommendations to improve the management of pastoral lands in WA …

Integrating Space Use And Demography To Support Management Of An Endangered Alpine Ungulate, Danielle J. Berger

All Graduate Theses and Dissertations, Fall 2023 to Present

The places animals choose to live affect the food they find, the dangers they face, and the weather conditions they experience. These experiences influence whether individual animals survive and reproduce, which in turn affects the size and health of animal populations. Although scientists have long believed that animal movements play an important role in population trends, there has been limited real-world evidence showing this connection. Advances in GPS tracking technology now allow researchers to follow animals over long periods and better understand how movement influences survival. Using 20 years of GPS tracking data from the endangered Sierra Nevada bighorn sheep …

Carbon Cycling, Salinization, And Long-Term Water Quality Trends In Rocky Mountain Streams, Allyson J. Marrs

All Graduate Theses and Dissertations, Fall 2023 to Present

Humans have greatly affected streams and rivers worldwide through urbanization, agriculture, and water use. The purpose of my dissertation is to increase our understanding of various human impacts on rivers. In chapter two, I aim to determine whether there are differences in greenhouse gas (GHG) emissions between a natural river and manmade canals. I did this by measuring the emissions and dissolved concentrations of three of the most prevalent GHGs, carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O). I found that most of the sites I studied were emitting CO₂ and CH …

Regional Occurrence And Spatiotemporal Habitat Partitioning Of The Culex Genus Mosquitoes In Salt Lake City And Uintah Basin, Utah, Katelyn Graybeal

All Graduate Theses and Dissertations, Fall 2023 to Present

West Nile virus is the most common mosquito-borne disease in North America and can cause serious illness, including inflammation of the brain and nervous system. Because there is currently no widely available vaccine for humans, preventing mosquito bites and monitoring mosquito populations remain the most effective ways to reduce disease risk. Understanding which mosquito species are present, where they occur, and how they respond to environmental change is critical for protecting public health.

This research examined the mosquito species responsible for spreading West Nile virus in Utah through two complementary studies. The first study focused on the Uinta Basin in …

The Role Of Individual Specialization In Migration Phenology And How Restored Habits Are Used By Native And Nonnative Fishes, Austin Garner

All Graduate Theses and Dissertations, Fall 2023 to Present

Native fish species around the world have declined due to habitat loss, habitat fragmentation, and the spread of non-native species. Because these problems often happen at the same time and interact, recovery efforts can stall unless they address all of the factors limiting a species' comeback. The June sucker (Chasmistes liorus), native only to Utah Lake, UT, has declined for many of these reasons, though its recovery effort has made significant progress due in large part to a successful hatchery program. Yet, the recovery efforts have not yet been able to establish a self-sustaining population in Utah Lake, …

Behavioral And Landscape Factors Affecting The Effectiveness Of Egg-Bait Management For Common Ravens In The Great Basin, Usa, Sierra L. Pederson

All Graduate Theses and Dissertations, Fall 2023 to Present

Common Ravens have become increasingly common across the Great Basin of the western USA, largely because human activities, such as roads, agriculture, livestock operations, and human-made structures, provide them with abundant food, water, and nesting sites. As raven numbers have grown, so has their impact on vulnerable species like the greater sage-grouse. Like many other ground-nesting species, greater sage-grouse eggs and chicks are especially susceptible to predation. To help reduce raven numbers in sensitive areas, wildlife managers often place hard-boiled chicken eggs treated with a toxin (DRC-1339) on the landscape, expecting that ravens will die after eating these eggs and …

The Influence Of Habitat And Individual Specialization On Mountain Lion (Puma Concolor) Hunting Strategy In A Multi-Prey System, Hannah B. Klugman

All Graduate Theses and Dissertations, Fall 2023 to Present

There is a growing recognition that animal species considered generalists (having a broad and varied diet), are actually specialists, a collection of individuals with different preferences and strategies known as specializations. The diet of a specialist depends on the variety and quantity of available food options, and their own ability to take what they need. Mountain lions (Puma concolor) are known for their ability and tendency to hunt large prey, such as elk (Cervus canadensis) and mule deer (Odocoileus hemionus), but despite the fact they overlap with other potential large prey, like feral horses …

Secure Agricultural Futures: Re-Defining And -Imagining Agricultural Water Landscapes In The Us West, Britta L. Schumacher

All Graduate Theses and Dissertations, Fall 2023 to Present

Aridity is swiftly becoming the US West’s new normal. As agricultural communities adjust to persistent growing-season scarcity, they find their livelihoods under increasing threat. This points to the urgency of finding paths toward more secure water futures. A piece of this future puzzle includes water (re-)distribution – taking excess from one place and delivering it to another in need. To begin thinking about (re-)distribution, this dissertation engages with three mixed-methods and multiscale studies. The first study pairs county-level data across the 11 westernmost US states with survey data collected from individual producers in Utah to assess past and current trends …

Understanding The Impact Of Environmental Change On Shorebird Abundance And Distribution Across The Intermountain West Over The Past 30 Years, Sharon Montecino

All Graduate Theses and Dissertations, Fall 2023 to Present

Shorebirds have declined worldwide over the past century, mainly due to wetland loss and degradation. Wetlands are sites that are temporarily or permanently flooded and provide critical habitat for shorebirds, especially in arid and semi-arid regions such as the Intermountain West. However, climate change and human water use threaten these wetlands, and how these threats may affect shorebirds in this region remains poorly understood. In the early 1990s, shorebird counts at over 160 wetlands across the Intermountain West provided a broad assessment of shorebird populations in the region. These counts remained the only large-scale surveys until 2022, when the Intermountain …

From Genes To Streams: Mitochondrial Approaches To Population Monitoring Of The Santa Ana Sucker Catostomus Santaanae, Mariana Antonio

Electronic Theses, Projects, and Dissertations

This study was developed to use aquatic environmental DNA (eDNA) as a tool to detect the presence of the Santa Ana sucker (Catostomus santaanae), a federally threatened fish species, across the Santa Ana River in Southern California. Environmental DNA is any genetic material that an organism sheds into the environment. We can get an idea of what aquatic species are present when sampling water at a given site. We sequenced the complete mitochondrial genome (mitogenome) of the Santa Ana sucker and designed custom DNA primers to improve eDNA detection accuracy. These primers were selected based on high genetic …

From Shallow To Upper Mesophotic Reefs: Examining Environmental Influences On Coral Physiology And Thermal Tolerance, Katherine Eileen Parker

Biological Sciences Theses & Dissertations

Coral reefs are increasingly threatened by rising ocean temperatures, yet coral thermal tolerance varies widely across species, populations, and environments. This dissertation investigates the biological and environmental mechanisms underlying coral thermal resilience, with a focus on symbiosis dynamics, photoacclimation, and the interaction between light and heat stress across environmental gradients. Specifically, it examines how coral-Symbiodiniaceae partnerships respond to thermal stress using the Coral Bleaching Automated Stress System (CBASS) across contrasting thermal and light environments, spanning population-level differences, depth-associated variation, and experimental manipulation of light during acute heat stress. First, thermal thresholds and transcriptomic dynamics were examined in two wild Porites …

Extinction Risk Of Coral Reef Fishes In The Philippine Marine Ornamental Trade, Jemelyn Grace Baldisimo Sepulveda

Biological Sciences Theses & Dissertations

Coral reef ecosystems in the Philippines face severe threats from intense fishing and habitat degradation. This dissertation evaluated the extinction risk of fishes in the Philippine Marine Aquarium Trade (MAT) using Productivity Susceptibility Analysis (PSA) and temporal genomics. A global PSA framework was modified by including local susceptibility factors. Of the 103 species evaluated, six were categorized as highly vulnerable and 62 as moderately vulnerable, revealing increased local vulnerability and underscoring the importance of local assessments to guide conservation efforts.

Temporal genomics compared historical (1908–1909 U.S.S. Albatross Expedition) and contemporary populations of the MAT-targeted Sphaeramia nematoptera and Pseudanthias squamipinnis, …

Long-Term Spatiotemporal Change In Coral Reef Fish Populations And Communities In The Philippines, John Christopher Whalen

Biological Sciences Theses & Dissertations

The Visayas Region of the Philippines is a global epicenter of marine fish biodiversity. Hypotheses attribute this peak of species richness within the Coral Triangle to processes that occur at geological time scales. However, changes in biodiversity may occur on ecological time scales, allowing for the assessment of the potential impact of anthropogenic activities. Recent declines in genetic, species, and ecosystem diversity have been observed in the tropics, including the Philippines. Within the Philippines the Visayas Region is considered the epicenter of species adversity due to anthropogenic stressors such as habitat degradation, overfishing, and harvesting individuals for the aquarium trade. …

The Role Of Phenotypic Plasticity And Bet-Hedging In Coping With Unpredictable Temperature Fluctuations In The Marine Annelid Ophryotrocha Labronica, Gabrielle Dawn Newton

Biological Sciences Theses & Dissertations

Coastal ecosystems are increasingly exposed to unpredictable temperature fluctuations, potentially favoring strategies that buffer populations against environmental uncertainty. This study examines how phenotypic plasticity and diversified bet-hedging contribute to variation in life-history traits under differing thermal predictability in the marine annelid Ophryotrocha labronica. After three generations at 24 °C, broods were reared for three generations under four thermal regimes: constant 24 °C (C24), constant 27 °C (C27), predictable fluctuations (Fp), and unpredictable fluctuations (Fu). Survival was assessed before and after acclimation to evaluate selective pressure among regimes. Age at maturity, fecundity, and growth rate were used to quantify plasticity (trait …

Evaluating Fish Assemblages At An Early-Stage Living Shoreline Project In Lake Pontchartrain, Collin Glaser

LSU New Orleans Theses and Dissertations

Living shorelines are an increasingly popular restoration approach for reducing erosion while improving habitat quality. The Bucktown Living Shoreline Project is a large-scale restoration effort along the southern shore of Lake Pontchartrain aimed at enhancing coastal resilience and restoring historic marsh habitat. This thesis evaluated early fish assemblage response to the Bucktown Living Shoreline Project over one year and placed those assemblages within the broader historical context of Lake Pontchartrain. Monthly sampling was conducted at the living shoreline and an adjacent riprap control site using seines, cast nets, and minnow traps. Fish assemblage structure was not significantly different between sites. …

Re-Examining Endemic Smoky Dace As An Indicator Species In The Upper Little Tennessee River Index Of Biological Integrity, Tayton C. Alvis, William O. Mclarney, Radmila Petric, Jason P. Love

Southeastern Fishes Council Proceedings

Fish communities can be used to evaluate water quality and stream ecosystem health, helping resource managers understand the effects of anthropogenic disturbance. Fish species inform indexes of biological integrity through their ecological traits and tolerance to stressors (e.g. tolerant of disturbance, intolerant of disturbance), but these designations are difficult to determine without localized, species-specific information. The Upper Little Tennessee River watershed is subject to long-term aquatic biomonitoring, applying an index of biological integrity tailored to the region. In this index, the undescribed endemic Smoky Dace (Clinostomus sp.) is classified as intolerant based on a previous designation for the Rosyside Dace …