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Exploring Factors Mediating White-Nose Syndrome In Little Brown Bats, Carly R. Trujillo

Graduate Theses/Dissertations

The little brown bat (Myotis lucifugus) has experienced drastic population declines across North America due to the recent disease white-nose syndrome (WNS). Previous studies have identified putatively adaptive alleles (PAAs) that may give individuals a greater likelihood of survival. However, there could be geographic-specific adaptation, creating different adaptive landscapes. Additionally, there may be energetic trade-offs between disease survival and reproductive output, and it is not clear what the long-term survival outcomes for the species may be as a result. Long-term evolutionary outcomes are unclear because this species has a lifespan exceeding the arrival of WNS and is difficult …

Compositional And Functional Shifts In Fish Community Structure In Response To Low-Head Dam Removals, Joshua D. Bruegge

Masters Theses

Low-head dams serve as intermittent barriers to aquatic connectivity and directly alter both upstream and downstream habitats and biotic communities. In 2018 and 2019, two low-head dams in the Vermilion River watershed of eastern Illinois were removed, reconnecting over 1,700 kilometers of upstream habitat within the basin. To determine the impacts of these dam removals, fish community surveys were conducted at 12 fixed sites across three reaches in two rivers from 2012-2022. This study assessed reach-specific temporal responses of the fish community and habitat characteristics. I linked trait expressions within the fish community to abiotic variables using the co-inertia RLQ …

Complexity Theory And Environmental Conservation Management: A Case Study With Coyote And Red Wolf Hybridization, Gretchen E. Mahalic

Honors Undergraduate Theses

Conservation biology and invasion biology are value-led scientific disciplines founded on environmental advocacy, operating at the intersection of research and action. Though these disciplines are known for their scientific veracity, unexamined values are often promulgated without scrutiny and drive decisions that work against good ecological outcomes. A case in point is that coyotes migrating into southeastern territory are framed as the greatest threat to the conservation of the endangered red wolf because hybridization is seen as diminishing their species integrity. Applying Val Plumwood’s ecofeminist account of dualistic frameworks, I will use this case to show how the vilification of the …

Climate, Biogeography, And Dispersal: A Unifying Framework For Ameri-Caribbean Dry Forests, Pablo Lopez Bustamante

Theses and Dissertations

Seed dispersal is a crucial ecological function that enables plants to alter their distributional range, avoid intense competition and natural enemies near the parent plant, and recover from disturbances. These processes shape species and functional composition of forests. Wind has traditionally been considered the dominant dispersal mechanism in Ameri-Caribbean dry forests, yet growing evidence suggests that other dispersal mechanisms also play significant roles in this ecosystem, responding differently to biotic and abiotic conditions. Still, how dispersal syndrome composition influences plant communities, the ecological drivers underlying these patterns, and the effects of climate change on dispersal syndrome dominance remain poorly understood. …

Sex In Plants: Birth, Death, And Trying To Survive In Changing Climates, Elena M. Meyer

Theses and Dissertations

Plant mating systems are key determinants of fitness. Angiosperms exhibit a wide variety of reproductive strategies, including self-fertilization (or selfing), outcrossing, and mixed mating. It has been estimated that up to 43% of plant species are capable of selfing, and selfing has been hypothesized to provide reproductive assurance where opportunities for mating may be limited, such as in marginal environments. However, questions regarding the overall distribution of selfing rates across angiosperms, the maintenance of mixed mating in the face of inbreeding depression, and the impact of self-fertilization on diversification rates remain incompletely resolved. Here, we explore the dynamics of self-fertilization …

Nutritional Niche Separation Amongst Sympatric Threatened Lemurs: The Role Of Micronutrients In Food Selection And Implications For Physiological Health, Maire K. O'Malley

Graduate Research Theses & Dissertations

Madagascar’s biodiversity is heavily affected by anthropogenic change and consequently, conservation management plans need to reflect current research to protect biodiversity. Primate nutritional ecology offers valuable insights into ecology, evolution, health, habitat requirements, social behavior, and conservation management strategies. Macronutrients (fat, carbohydrates, and protein) provide consumers with energy whereas micronutrients (vitamins and minerals) are essential to metabolic processes but are frequently overlooked. This study provides a novel examination of dietary niche separation by comparing mineral consumption between three sympatric species differing in feeding strategies: 1) Grey Bamboo lemur (Hapalemur griseus), a bamboo specialist, 2) Diadema sifaka (Propithecus diadema), a folivore, …

Layers Of Biodiversity: Linking Urban Garden Plants And Arthropods, Chenyang Su

Dartmouth College Ph.D Dissertations

Diverse arthropods play essential roles in urban agriculture, while urban agriculture provides food and habitat that support arthropod biodiversity in fragmented urban landscapes. In urban community gardens, a form of urban agriculture characterized by allotment-style gardens, arthropods interact with plants and green space across multiple spatial scales of management, from individual gardeners' plots to broad urban landscapes. Understanding how plant communities in urban community gardens and urban landscapes shape arthropod biodiversity and interactions across scales can inform both agricultural management and urban biodiversity conservation. In this thesis, I conducted a series of field studies on ecologically and economically important arthropods …

Evaluating Planting Methods For Native Seed Production And Exploring Granivory In The Northern Great Plains, Allison Dollen

Electronic Theses and Dissertations

Temperate grasslands have faced immense losses due to land use change in the last 150 years and less than half of the overall grasslands that once covered North America remain today. A portion of historic and remaining U.S. grasslands are located within the northern Great Plains (NGP) region which is home to over 1,600 species of native plants and provides many ecosystem services and economic benefits. Initiatives to restore grasslands and their ecosystem services are currently underway, but barriers such as limited native seed supply and granivory hinder restoration efforts. My first chapter addresses knowledge gaps in planting methods for …

Non-Native Seagrass, Halophila Stipulacea, Reaches Northern Caribbean, Elizabeth R. Whitman, Elizabeth W. Stoner, Stephanie K. Archer

Gulf and Caribbean Research

Halophila stipulacea, a seagrass native to the western Indian Ocean, has become an established invader throughout the western Atlantic, where it often outcompetes native seagrass species across diverse environmental conditions. Here, we report its presence in the northern Bahamas, ca. 2300 km northwest of the first Caribbean record in Grenada and 304 km northeast of the recent observation in Florida, USA. This range expansion represents the northernmost Caribbean record to date and highlights the species’ capacity for long-distance dispersal and continued spread within the region. Our observation underscores the need for coordinated monitoring efforts to track the trajectory of …

Manatee Dock Sign Distribution And Its Influence On Publicly-Sourced Sighting Reports In Alabama, Daniela Payán Arias, Sophia C. Corde, Ruth H. Carmichael

Gulf and Caribbean Research

No abstract provided.

Using Side Looking Hydroacoustics And Community Size Spectra To Assess Invasive Carp’S Impact On Fish Assemblage Integrity, Daniel Jacob Bryan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Often accounting for over half of total fish biomass, invasive silver carp have dramatically reshaped the ecosystem of the Mississippi River and its tributaries. These high silver carp densities have been shown to affect native fish body condition, abundance, and community structure, highlighting the need for efficient methods to quantify silver carp’s effect on the native fish assemblage. Community size spectra (CSS) is a metric that quantifies fish assemblage body size structure based on the decrease in fish abundance with increasing size. To estimate silver carp’s effects on CSS in the Ohio River, side looking hydroacoustic monitoring was used alongside …

Assessing Climate-Driven Shifts In Floral Resource Availability For Bees On Barrier Islands In The Southeastern U.S., Hannah Brown

College of Graduate Studies: Theses & Dissertations

Climate change can alter the timing of bee and angiosperm phenology, potentially reshaping the seasonal availability of floral resources for bee species. Although plant-pollinator phenology has been widely studied in temperate systems, less is known about these dynamics in subtropical coastal ecosystems, such as barrier islands in the southeastern United States. In this study, we examined climate-driven changes in bee activity and floral resource availability across 16 barrier-island sites spanning from Florida to Virginia. Using museum bee occurrence records, herbarium-derived flowering phenology models, site-specific floristic inventories, and published bee-plant interaction data, we estimated species-specific bee activity periods and daily floral …

The Influence Of Localized Water Quality On Eastern Oysters (Crassostrea Virginica) And Their Internal Microbiome Under Changing Environmental Conditions, Jessie Rivera Lafreniere

College of Graduate Studies: Theses & Dissertations

Oysters are found ubiquitously in estuaries along the Georgia coast, where marsh morphology and large daily tidal fluctuations create dynamic and stressful conditions to which oysters may be locally adapted. Based on water quality data from the Sapelo Island National Estuarine Research Reserve, it is evident that changing climatic conditions are rapidly causing shifts in water quality that may be adversely affecting oyster health, especially as ocean acidification alters the carbonate buffering capacity, increasing the amplitude of daily pH variations. Importantly, the rate of change of conditions are not uniform within estuaries, varying on spatial and temporal scales. The symbiotic …

Cytonuclear Incompatibilities In Hybrid Systems: Oxidative Phosphorylation Capacity And Nuclear Marker Transmission Ratio Distortion In Hybrids Of An Introgressed Strain Of Parasitoid Wasp, Julie Kessler

College of Graduate Studies: Theses & Dissertations

Speciation is an evolutionary process resulting in the divergence of populations into reproductively isolated species, a key concept that supplies our planet with an abundance of biodiversity. Mechanisms for speciation center on obstacles to fertilization and include post-zygotic barriers, such as intrinsic deleterious interactions, that arise in hybrid systems where genetic variants are combined. Genes from separate parent lineages are often incompatible due to the co-evolution of paired genes within a singular species not matching their complement genes in another species, and the result is a reduction in fitness of the hybrid when these genes come together. The mitochondrial OXPHOS …

Evaluating Donor Site Recovery Following Halodule Wrightii Harvest For Restoration In Northwest Florida, Katie M. Konchar, Becca A. Hatchell, Colin P. Shea, Bradley T. Furman, Kent Smith

Gulf and Caribbean Research

Bare‑root harvesting of Halodule wrightii is widely used to supply donor material for seagrass restoration, yet the capacity of donor meadows to recover in near‑temperate systems remains poorly documented. We evaluated donor‑site recovery following bare‑root harvesting in St. Andrew Bay, northwest Florida—an estuary at the northern extent of Tropical Atlantic Bioregion 2 where H. wrightii exhibits strong seasonal senescence and a shortened growing season. Thirty harvest impact sites were monitored for 388 days to quantify changes in shoot density, percent frequency, and sediment elevation relative to nearby reference conditions. Shoot density and percent frequency at harvested sites converged with reference …

Comparative Analysis Of Six New Chloroplast Genomes In Platanthera (Orchidaceae) Enhances Understanding Of Its Diversification, Lisa E. Wallace, Martin I. Batalla, Matthew Maisonave

Biological Sciences Faculty Publications

Platanthera is among the most diverse genera of orchids in north temperate regions, with high species diversity in Asia and North America. Despite many ecological studies in this group, little is known about its genomic diversity. Here, we report the newly annotated chloroplast genomes from six species in subgenus Limnorchis from North America and compare them with plastomes published for Platanthera species from Asia and Europe. We found that the plastomes of species in subg. Limnorchis are among the smallest reported for Platanthera thus far. While major structural differences were not detected in the newly sequenced species, ndh genes were …

Challenging And Diagnosing Structured Population Models By Testing Predictions From Stochastic Demography, Stephen P. Ellner, Robin E. Snyder, Daniel T. Blumstein, Dylan Z. Childs, Joshua C. Fowler, Christina M. Hernández, Julien G. A. Martin, María Paniw, Yngvild Vindenes

Biological Sciences Faculty Publications

1. Structured population models are parameterized to accurately project expected population sizes, stage/state distributions and population growth rates, but they also predict the variation in outcomes among individuals, such as the variance and skewness of lifetime reproductive output (LRO) and lifespan, the probability of never reproducing, and many other life-history metrics.

2. Testing such predictions about individual outcomes can be very useful model 'stress tests', because they depend on how components of the model (e.g. submodels for survival and fecundity) interact over multiple time steps, not just on the accuracy of the submodels. Because data on among-individual variation is rarely …

A Note On The Novel Passive Sampling In Environmental Dna (Edna) Collection Technique To Detect Yellow Mud Turtle (Kinosternon Flavescens): Field And Laboratory Approaches In Turtle Edna, Sakib Tahmid Rishan, Richard J. Kline, Md. Saydur Rahman

School of Integrative Biological & Chemical Sciences Faculty Publications

Environmental DNA (eDNA) is a powerful and sensitive method for monitoring aquatic and terrestrial organisms, offering insights into their distribution. Usually, eDNA is collected using a filter membrane through water filtration. However, the passive eDNA method can simplify sampling and broaden its scope, offering new insights for ecological surveillance. This study examined the efficacy of six different membrane filters in detecting the yellow mud turtle (Kinosternon flavescens) through a novel passive eDNA method. After being immersed in water for 12 h, only the mixed cellulose ester (MCE) membrane filter consistently demonstrated specific polymerase chain reaction (PCR) amplification using …

Larval Crowding In Culex Pipiens Generates Cumulative Cascading Effects Under Changing Environmental Conditions, Sengul Talay, Zafer Sakaci, Michele C. Weigle, Bugrahan Regaip Kilinc, Jenah Parman, Holly Gaff, Deniz Sirin, Bulent Alten, Dennis Bente, Sirri Kar

Computer Science Faculty Publications

Density-dependent population regulation is a fundamental driver in the population dynamics of living systems, ensuring a balanced and sustainable maintenance in nature. It has been suggested that the adverse developmental and morphological effect of high larval density in container mosquitoes represents a significant limiting factor for population density, and the need to investigate this possible importance within the framework of field-based principles has been emphasized. This semi-field study, conducted under the natural thermal regime and using a natural population in Turkish Thrace, aimed to examine the effects of non-food-limiting larval density (crowding effect) in the mosquito species, Culex pipiens ( …

Intensified Push-Pull Technology Enhances Above-Ground Arthropod Assemblages And Ecological Balance, Evanson R. Omuse, Honest Machekano, Daniel M. Mutyambai, Bonoukpoe M. Sokame, Chrysantus M. Tanga, Johnson O. Nyasani, Sevgan Subramanian, Frank Chidawanyika

All Peer-Reviewed Publications

Agroecological intensification aims to increase farm productivity, reduce dependency on external inputs, and enhance biodiversity conservation. However, the contribution of recent sustainable agricultural practices to arthropod assemblages and their ecosystem services remains underexplored. Through a 2-year multilocation trial, we investigated the response of above-ground arthropod assemblages and their ecological functions in cowpea and maize grown under monocropping systems and diversified systems (pure and intensified push-pull technologies). Using three sampling methods (visual observations, pitfall traps, sticky traps), a total of 65, 307 arthropod specimens were collected. The most dominant arthropod taxa were Hemiptera (true bugs; 47%), followed by Thysanoptera (thrips; 17%), …

Viral Diversification And Host-Specific Fitness Of Powassan, Heartland, And Bourbon Viruses In New York State, Rachel E. Lange

Electronic Theses & Dissertations (2024 - present)

This dissertation reports important progress for our understanding of emerging and re-emerging tick-borne viruses circulating in North America including Powassan, Deer Tick, Heartland, and Bourbon viruses. Chapter 2 describes important tools for these viruses including multiplex assays for viral and bacterial pathogens in field-collected ticks and mammals, development of full genome sequencing assays and bioinformatic pipelines for evolutionary analysis, and establishment of tick-specific tools for viral isolation and characterization. Chapter 3 focuses on the disease focality of Deer Tick virus, reporting transovarial transmission in nature in Ixodes scapularis for the first time, further evidence to incriminate shrews as potential Deer …

Population Genomics And Evolution Of Pseudomonas Aeruginosa, Samara T. Choudhury

Electronic Theses & Dissertations (2024 - present)

Pseudomonas aeruginosa is a Gram-negative bacterium ubiquitous in diverse environments and an opportunistic pathogen in humans. It is a leading cause of chronic lung infections in cystic fibrosis patients and of hospital-acquired pneumonia and sepsis. With a large flexible genome and abundant mobile genetic elements, P. aeruginosa exhibits high levels of antimicrobial resistance (AMR), making it a significant public health threat. Evolutionary processes such as homologous recombination, and horizontal gene transfer generate extensive genomic diversity in this species and facilitate the spread of resistance genes. In this dissertation, I investigate the genetic and evolutionary factors shaping P. aeruginosa population structure …

Using Genetic Analysis To Infer Familial Relationships Of Westslope Cutthroat Trout In The Lower Priest River, Idaho, Kolby Emtman

EWU Masters Thesis Collection

The Westslope Cutthroat Trout (Oncorhynchus lewisi) is a native species of salmonid that holds both cultural and ecological significance in the Idaho Panhandle region of the United States. Within this region, the Priest River is a major contributor of migrant Westslope Cutthroat Trout to the Clark Fork Pend Oreille basin. This study aimed to estimate the proportion of juveniles that have at least one migrant parent, illustrate gene flow using juvenile half sibling relationships, and showcase varying levels of spawning success using juvenile full sibling relationships. Sampling of juvenile individuals occurred in 11 tributaries of the Priest River over …

Assessing Forest Health And Small Mammals After A Limited Suppression Wildfire In Colville National Forest, Samantha J. Kennel

EWU Masters Thesis Collection

In the face of a wildfire crisis, there is a growing need to expand the pace and scale of forest treatments, including the strategic use of wildfire as a management tool. However, ecological outcomes remain uncertain in forests shaped by more than a century of fire suppression. The 2022 Thor Fire, a managed wildfire in the Colville National Forest, Washington, provides an opportunity to evaluate forest health in a relatively understudied system. Using a control–impact design, I established 100 monitoring plots in burned and adjacent unburned forests to assess how wildfire and fire severity influence forest structure, fuels, and tree …

Dietary Ecology Of Waterfowl Nest Predators In The Prairie Pothole Region: Evaluating Resource Use From Species To Individual Using Stable Isotope Analysis, Grace Barthelmess

EWU Masters Thesis Collection

Nest predation is a primary factor influencing waterfowl productivity in the Prairie Pothole Region (PPR) of North America. Although this system is intensely managed and studied, research has largely focused on how predators affect waterfowl populations, with comparatively little attention to how predators actually rely on waterfowl as a resource. Understanding predator feeding ecology is therefore critical for informing effective management strategies and interpreting the complexity of predator-prey interactions on this landscape. My objective overall was to elucidate the feeding ecology of nine focal predator species commonly associated with waterfowl nest predation in the Aspen Parkland Ecoregion of the PPR: …

Adapting To Uncertainty: Effects Of Environmental Instability On Zebrafish Behaviour, Britney Sekulovski

Theses and Dissertations (Comprehensive)

This thesis addresses how animals cope with unpredictability by testing how environmental stability changes the behaviour of zebrafish (Danio rerio) in two complementary experiments. In Experiment 1, fish lived for three months in either a Dynamic environment (water temperature, feeding times, habitat complexity, group size, and membership fluctuated) or a Stable environment (all factors constant). Across seven behavioural assays, measuring individual behavioural differences, collective movement, social memory, and information use, Dynamic condition fish were found to be more sensitive to social cues and more likely to conform to recent social information, independent of the quality of the information …

Analysis Of Alternative Oxidase In Non-Angiosperm Plants, Anissa M. Francis

Theses and Dissertations (Comprehensive)

Alternative oxidase (AOX) is a mitochondrial terminal oxidase that provides an alternative pathway for electron transport, allowing plants to maintain respiratory flexibility under environmental stress conditions. While AOX has been extensively studied in angiosperms (flowering plants), little is known about its distribution and conservation in non-angiosperms. Based on gaps identified in the literature, this thesis investigated the distribution of AOX across non-angiosperm plant lineages. Although AOX is present in many green algae and is therefore considered to be an ancient protein that originated before the existence of non-angiosperm plants, it remains unclear whether the protein is uniformly distributed across these …

Homoplasy Of Maxillary Orthognathism In Derived Homo, Jared Jordan

Graduate Studies Theses and Dissertations 2026

The evolution of the orthognathic condition in the genus Homo represents a monumental transition toward the facial morphology of modern humans from that of earlier hominins, but the phylogenetic positioning of this transformation remains poorly understood. This study investigated temporal trends in maxillary and mandibular prognathism in the genus Homo, and whether maxillary and mandibular shortening in East Asian H. erectus and later East Asian Middle Pleistocene Homo (e.g., Homo longi) represent independent derivations of orthognathic morphology, thereby making orthognathism a homoplasy in the genus Homo. Using a sample of roughly 109 cranial and mandibular specimens spanning …

Green Connectivity In Metropolitan Jabodetabek: Climate Change And The Challenge Of Urban Forest, Safira Maharani Putri, Hendricus Andy Simarmata

CSID Journal of Infrastructure Development

Urban areas in Indonesia, particularly the Greater Jakarta metropolitan region (Jabodetabek), are increasingly experiencing the adverse effects of climate change, such as the Urban Heat Island (UHI) phenomenon. Rapid urbanization has contributed significantly to rising greenhouse gas emissions and deteriorating environmental quality. Urban forests are one of the key solutions to mitigate these impacts; however, their spatial distribution in Jabodetabek remains suboptimal and poorly connected. This study uses NDVI as a proxy for urban forest density, where “urban forest” refers to vegetated areas within cities as defined by Presidential Regulation No. 60/2020. The research addresses the following question: How has …

Change In Community Composition And Structure On Subtidal Rock Walls In The Gulf Of Maine Over Four Decades Of Warming, Breck A. Mccollum

Graduate Doctoral Dissertations

The Gulf of Maine (GOM) has faced many changes over the last 47 years from overfishing of its iconic cod fish stocks to the introduction on non-native species, but no change has been as dramatic as the warming ocean temperatures that began to increase rapidly in the 2010s. This thermal shift is due largely to the northward movement of the Gulf Stream current mixing with Arctic meltwater before entering the GOM. Average summer temperatures jumped by 3.35°C between the periods of 1980-1985 and 2015-2020. This warming trend, combined with an increasing frequency of marine heat wave events, has led to …