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Factors Associated With Acoustic Bat Presence During Spring Emergence In The Appalachian Mountains Of Western Virginia, Emily Kirk Pody

Theses, Dissertations and Capstones

Studies of threats that bats face during hibernation have increased in response to white-nose syndrome (WNS), a fungal disease that has ravaged North American bat populations. However, impacts of WNS on bat ecology during spring emergence, when bats are potentially recovering from infection and allocating resources for reproduction, is relatively understudied. As more bat species become listed at the federal and state level, the need to understand the factors associated with spring emergence is critical for improving conservation guidelines and habitat management practices. Acoustic monitoring is an efficient method for monitoring bat presence for prolonged periods of time, giving biologists …

A Comparative Study Of Biocrusts On Gypsum And Non-Gypsum Soils In The Northern Chihuahuan And Eastern Mojave Deserts, Usa: Biocrust Mosses Respond To Soil, Environmental, And Climatic Conditions, Katelyn Gobbie

Masters Theses

Biological soil crust communities (biocrusts) growing on gypsum soils have been well- documented for their prolific appearance and rich diversity of lichens and bryophytes. However, studies characterizing gypsum biocrusts have primarily occurred outside of the U.S., most of which lack comparisons to other soil types. We conducted intensive field surveys to evaluate the cover and frequency of biocrust functional groups and moss species on gypsum and non-gypsum soils in the U.S. regions with the most extensive gypsum outcrops, the northern Chihuahuan and eastern Mojave Deserts. We employed canonical correspondence analysis (CCA) to relate the observed differences in biocrust abundance and …

Environmental Biology Masters Capstone, Antonio Gonzalez-Pita

Regis University Student Publications (comprehensive collection)

Human wildlife interactions (HWI) pose a complex challenge for wildlife managers. Human encroachment into wildlife habitat and the growing number of outdoor recreationists are increasing the frequency of contact and conflict, especially in regions such as the Front Range of Colorado. Geographic information systems (GIS), which use a combination of remote sensing and environmental survey data, allow for predictive spatial analyses of where human wildlife interactions are likely to occur. I used publicly reported observations of moose to create spatial predictive maps in a species distribution model framework. Slope and elevation were shown to be the strongest predictors of HWI, …

Habitat And Demography Of The Ozark Chinquapin (Castanea Ozarkensis) At Roaring River State Park In Barry County, Missouri, Danielle Evilsizor

Electronic Theses & Dissertations

The Ozark chinquapin, Castanea ozarkensis Ashe, is a chestnut tree with a range concentrated in the Interior Highlands of North America. Like other North American members of Castanea, it was reduced from an overstory tree to an understory shrub by the invasive chestnut blight fungus (Cryphonectria parasitica [Murrill] M.E. Barr) during the early 20^th century. However, relatively little is known about the habitat of this species or its health and reproductive capability post chestnut blight. Chapter one of this study analyzed the habitat of this species through a random forest species distribution model (SDM) to predict where …

The Interaction Between Predation And Sound Pollution On The Internal And External Microbiome Of The Grasshoppers Melanopus Sanguinipes, Alanna Bond

Theses and Dissertations

Anthropogenic activities such as construction and agriculture directly affect its surrounding environments. Many studies have focused on how megafauna and flora are impacted by human activities, however, relatively little is known how new occupation of land affects smaller organisms such as insects and microbes. Additionally, other stressors such as predation can impact host physiology. The grasshopper species Melanopussanguinipes was chosen to be used in a study to measure how stress caused by artificial sound and predation can alter exoskeleton and gut microbiomes once exposed to these stressors.

An Ecological Survey Of East Texas Salamanders Across The Camp Tyler Outdoor Field School In Smith County, Texas, Justin C. Hunt

Biology Theses

Amphibians are a unique class of organisms with a very long and storied evolutionary history of survival. Many modern amphibian clades occupy several vital ecological roles within their native freshwater environments. One of these roles, typically includes functioning as an ecological indicator species, whereby the presence of stable and diverse populations of many amphibian species, including salamanders, within a freshwater ecosystem have long been considered ecological indicators of good habitat quality and stable ecosystem health. Similarly, salamanders also function as important members of their local food webs and act as valuable mediators of complex trophic hierarchies to facilitate nutrient cycling …

Monitoring The Effects Of Poultry Waste On Fishes And Macroinvertebrates In The Sabine River, Karley R. Parker

Biology Theses

Freshwater is a vital resource that provides life and sustainability for almost all organisms on Earth. It is important to maintain its health and protect it from emerging pollutants that pose a threat to the organisms that use it. Pollution continues to threaten the well-being of the environment’s freshwater sources all around the world that could lead to damaging effects in the future. The Sabine River is a major freshwater resource in the east Texas and western Louisiana areas that provides a habitat for thousands of organisms as well as other domestic uses for humans. In 2019, a waste discharge …

Consequences Of Host Life Cycles For Symbiont Genome Evolution, Ashley Elizabeth Dederich

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Aphids are small insects that feed exclusively on plant sap, a notoriously low source of nutrients due to the high sugar content and low amino acid content. To make up for these deficiencies in nutrition, aphids harbor Buchnera aphidicola, a bacterial endosymbiont that resides in a specialized organ called the bacteriome. B. aphidicola provides essential amino acids and vitamins for the aphid in exchange for a safe place to live. Over the course of the symbiosis (established 160 million years ago), B. aphidicola has lost much of its genome, including essential genes for cell envelope synthesis, DNA replication and …

The Effects Of Habitat Isolation On Fine-Scale Genetic And Geographic Structure Of Populations Of Two Threatened Endemic Insects In Southern Nevada, Pseudocotalpa Giulianii And Icaricia Shasta Charlestonensis, Kristen Tovar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Assessing the role geographic isolation and ecological specialization have on phylogeographic patterns contributes to our understanding of the evolutionary history of a species and the processes that erode genetic diversity. I used mitochondrial and nuclear genomic sequences to assess whether habitat isolation has shaped the fine-scale patterns of present-day genetic structure and diversity in two threatened insect species endemic to southern Nevada. Pseudocotalpa giulianii (Coleoptera; Scarabaeidae) is a dune obligate scarab beetle endemic to only two small, isolated sand dunes in Nye County, Nevada, with a usable habitat of less than 4.2 km sq that is impacted by on-going degradation. …

Testing For Relationships Between Animal Personality Traits, Activity Level And Voracity, And The Underlying Influence Of Body Size In The Dragonfly Predator, Epitheca Canis, Flynn Gorman

Senior Theses and Projects

Animal personality, defined as among-individual variation in behavior, is taxonomically widespread, but its ecological implications remain unclear. While associations between animal personality and ecological traits have been examined, methodological shortcomings, such as lack of repeated measurements, limit the insights these studies provide. Here, I measured the repeatability of activity level and feeding rate behaviors in the nymph stage of the dragonfly predator, Epitheca canis, taking 10 repeated measurements of each trait over a 10-week period. Moreover, I tested for a relationship between among-individual variation in activity level and feeding rate while accounting for the underlying influence of nymph body …

The Effect Of Environmental Factors On Movement Patterns And Habitat Use Of Young-Of-The-Year Scalloped Hammerhead Sharks (Sphyrna Lewini) In The Tolomato River Nursery, Matthew Bernanke

UNF Graduate Theses and Dissertations

Various shark populations on the southeastern coast of the United States experienced declines in the late 20^th century, including the scalloped hammerhead shark (Sphyrna lewini). Improved management strategies, implemented in the late 1990s, have helped these populations to recover, but they are still under threat from fishing pressure and habitat loss. In continuing to strive towards population recovery and conservation, it is important to identify Essential Fish Habitat, or habitats that are necessary for the spawning, feeding, breeding, or growth of marine organisms. One such habitat is that of the shark nursery habitat. Nursery habitats are those …

Habitat Associations And Fine-Scale Movements Of The Red-Spotted Toad (Anaxyrus Punctatus) In Kansas And The Efficacy Of Remote Telemetry For Monitoring Small-Scale Movements, Elisabeth Russell

Master's Theses

As climate change progresses, arid-adapted anurans might be particularly susceptible to population declines because of their reliance on ephemeral pools for successful reproduction. Because arid-adapted anurans are difficult to study due to short active seasons and cryptic lifestyles, little is known about their habitat preferences. One such arid-adapted species is the Red-Spotted Toad (Anaxyrus punctatus; RST), a Kansas Species in Need of Conservation. Since this designation in 1987, little research has been conducted to understand their conservation needs. During the summers of 2021 and 2022, RST surveys were conducted both near areas where the species has historically been …

Microplastics In Wetlands Of West Central Ohio : Concentration And Distribution, Mitchell Link

Browse all Theses and Dissertations

Wetlands provide many valuable ecosystem services; however, an emerging global contaminant—microplastic (< 5 mm)—may be degrading this important resource. Few studies have extensively surveyed microplastic distribution in wetlands over a broad spatial area. Therefore, the goal of this study is to identify where microplastics are accumulating in wetlands, and whether there is any correlation between microplastic concentration and wetland quality. Soil samples were collected from 30 wetlands in west–central Ohio. Samples were physically separated, density separated, and digested. Average microplastic concentrations were 637 ± 494 items per kg soil per wetland. Higher quality wetlands are accumulating larger concentrations of microplastics. This relationship seems to be driven by greater accumulation of microplastics in forested wetlands than in wetlands surrounded by agriculture. There is no clear distribution pattern of microplastics within wetlands. These results provide insight into the role that wetlands have in association with microplastic accumulation.

To What Extent Do Non-Native Shrubs Support Higher Trophic Levels?, Ari Zakroff

Browse all Theses and Dissertations

Invasive species threaten ecosystems and economies. Globally, biological invasions are estimated to have cost over $2.1 trillion since 1970. In Eastern North American woodlands, invasive plants are rapidly displacing natives. This is concerning, because invasive plants may not support the diverse and abundant arthropod communities essential to ecosystem function. Despite the conceptual understanding of invasive shrubs’ potential to transform forest communities, scant research has focused on the effect of invasive plants on higher trophic levels here in Ohio. To address this gap, I examined the diversity and abundance of arthropod communities, caterpillar performance, and caterpillar predation on two invasive shrubs, …

Differences In Drifting Invertebrate Communities Across Arctic Ecozones And The Influence On Potential Growth Of Grayling (Thymallus Arcticus), Charles Chanyi

Theses and Dissertations (Comprehensive)

Invertebrate drift is a key process that potentially affects multiple levels of food web organization within stream environments. However, our understanding of the mechanistic drivers of drift in high latitude streams and subsequent bottom-up control that drift may have on fish predators in these environments remains understudied. This project aimed to gain the baseline knowledge of how drift functions across two major high latitude ecozones, the boreal forest and tundra, and how those possible differences in drifting community characteristics may impact drift-feeding Arctic grayling (Thymallus arcticus). These objectives were accomplished by characterizing stream environments across both ecozones, sampling …

Ecology And Evolution Of Social Information Use, Clare T. M. Doherty

Dartmouth College Ph.D Dissertations

Sociality is a strategy many animals employ to cope with their environments, enabling them to survive and reproduce more successfully than would otherwise be possible. When navigating their environments and making decisions, social individuals often use information provided by conspecifics (in the form of social cues and signals), thereby increasing the scope and reliability of the information they can gather. However, social information use may be influenced by many factors, including key differences in context across the physical and social environment. My thesis asks and answers a series of questions regarding the trade-offs in social information use across different contexts, …

Niche Overlap In Sympatric Rocio (Teleostei: Cichlidae) Of Guatemala, Cesar Estuardo Fuentes Montejo

College of Science and Health Theses and Dissertations

Rocio is a small genus of Neotropical freshwater fishes that is distributed in Atlantic drainages of northern Middle America. Two species in the genus exhibit sympatry in the Río Dulce basin (in Izabal, Guatemala), where one species is endemic (R. spinosissima), while the other only includes this area as part of a larger geographic range (R. octofasciata). Unfortunately, the ecology of these species has been poorly studied. This study sought to determine the ecological and morphological differences between these two closely related sympatric freshwater fishes. We hypothesized that R. octofasciata would exhibit greater ecological and morphological …

Effects Of Mass Death On Community Structure And Ecosystem Function, Abby Kimpton Jones

Theses and Dissertations

Death and decomposition are natural processes that are generally well-understood. However, large events of death, such as mass mortality events (MMEs) are increasing in frequency and their impacts on the ecosystem are largely unknown. These events may have both bottom-up effects from increased nutrient input as well as top-down effects from loss of an ecological functional group by the affected population. Different functional MMEs may result in different top-down effects, creating cascading effects. In Chapter 1, I test the hypothesis that scavenger and herbivore simulated MMEs generate novel bottom-up and top-down effects. Results indicate that MMEs have a significant effect …

Regional-Scale Climate-Induced Variation In Ant Physiology And Morphology, Daniel E. Murphy

Biology Theses

The biology of ectotherms such as insects is influenced by ambient thermal conditions. Ants are a ubiquitous and ecologically important group of insects and are well-established as bioindicators of thermal conditions. Ants are sensitive to the thermal extremes that vary with latitude, elevation, and land use, and these thermal gradients influence their spatial and temporal distributions. As a result, ants have evolved physiological and morphological thermal adaptations in response to the thermal environment of their habitats. These adaptations include increased physiological and morphological tolerance for temperature extremes. In Western New York (WNY), temperatures are temporally and spatially heterogeneous, changing with …

Fire And Periodical Cicadas: Impacts On Soil Nutrients And Understory Plant Germination, Andrea Gamache

Master of Science in Integrative Biology Theses

Purpose

A compound disturbance, composed of a prescribed fire and a periodical cicada emergence, occurred in northern Georgia in the summer of 2021. Independently these disturbances have substantial effects on the surrounding ecosystems. This study investigated the collective impact on soil composition and seed germination.

Methods

Through the soil analysis of cicada turrets, burned soil, and unburned soil, we hope to understand the composition of each soil type. Additionally, a 2 x 2 factorial study was performed with those same samples, providing insight into the impact on seed germination these disturbances have. The two factors were between burned and unburned …

Discovery Of Truffles (Tuber Species) In North Mississippi Pecan Orchards, Scout Hodges

Honors Theses

This thesis describes a study conducted in the years 2019-2022, which aimed to discover a new species of truffle in the state of Mississippi. Tuber lyonii, more commonly referred to as the “pecan truffle,” is an ectomycorrhizal fungus found on the roots of pecan trees in much of the southeastern region of the United States. Though there are many truffles native to the United States, the pecan truffle is one of the few that has been found to have high culinary value. Given the plethora of pecan orchards in the state of Mississippi, I decided to search for evidence …

Impact Of Genetic Variation And Timescale On Diatom Salinity Stress Response, Kala M. Downey

Graduate Theses and Dissertations

Natural environments are dynamic, and organisms must sense and respond to changing conditions. One common way organisms deal with stressful environments is through gene expression changes, allowing for stress acclimation and resistance which occurs over varying time spans in different species. The recent evolutionary history of populations could greatly influence their ability to respond successfully. An evolutionary history in disturbed or fluctuating conditions could promote increased resistance or a more rapid response to these environmental stressors. To understand the impact of genotypic variation and timescales on response and acclimation to salinity changes, we have been exploiting the abilities of euryhaline …

A Multi-Spatial Analysis Of Land Use Effects On Freshwater Mussels In The Upper Cuyahoga River And Tinkers Creek, Tamar Atwell

ETD Archive

Mussels are considered one indicator of good water quality in rivers, but over the past 20 years mussel populations have continued to decline, while water quality improves. According to the Ohio Environmental Protection Agency (OEPA), water quality in the Cuyahoga River is now within safe levels for all parameters. However, what are safe levels for humans may not be safe for mussels. An analysis of freshwater mussel populations in two similarly sized watersheds, the Upper Cuyahoga River and Tinkers Creek was conducted. Correlations of mussel abundance and diversity were assessed by multivariate GIS/remote sensing tools to contrast water flow rates, …

Analysis And Identification Of Lipolytic Bacterial Species For The Degradation Of Wastewater Lipids, Lindsay C. Smoak

Honors College Theses

The aim of this study was to isolate native bacterial strains from the wastewater treatment facilities of Statesboro, GA to identify their lipolytic activities. Obtained bacterial strains were further assessed via morphological and biochemical methods to determine their enzymatic capabilities. Use of the detergent Tween-20 in growth mediums was the first criteria to assess lipase activity, and these isolates were further investigated to quantitatively measure lipase presence and activity. Lipase protein was precipitated and dialyzed to perform a lipase activity assay, followed by Sodium Dodecyl Sulphate–Polyacrylamide Gel Electrophoresis (SDS-PAGE) to confirm the presence of the lipolytic enzymes. Sanger sequencing was …

Understanding The Genomic Influence And Virulence Capabilities Of Environmentally Isolated Vibrios, Shannon Elizabeth Pipes

Theses and Dissertations

The genus Vibrio consists of Gram-negative bacteria that possess a curved rod shape and are routinely isolated from estuarine and coastal salt water. Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus are the major three species that contribute to human disease worldwide, and a variety of other Vibrio species contribute to persistent problems in the aquaculture and fishing industries. The CDC estimates that vibrios cause 80,000 cases of disease each year in the United States alone, however, this number is thought to be underestimated, since some disease is only self-limiting, meaning patients may not seek medical treatment and have …

Geographic Range Size As A Predictor Of Dispersal-Dependent Behavioral Traits In Two Clades Of A Terrestrial Salamander, Teah Evers

Masters Theses

Animal movement has the potential to affect diverse processes within ecology and evolution including range expansion, gene flow, adaptation, and speciation. Two aspects of animal personality that are germane to dispersal are exploratory and aggressive behavior. These behavioral categories may represent a trade-off such that energy invested in territorial defense leaves little energy for movement and dispersal. The Eastern Red-backed Salamander (Plethodon cinereus) is a wide ranging, dispersal limited, terrestrial salamander with well documented phylogeographic divisions. I examined dispersal-relevant behavioral traits within two clades of P. cinereus with disparate geographic ranges. The Northern Clade (NC) has a range extending from …

Bottom-Up Effects Of Degradation Outweighs Stabilizing Potential Of Omnivores, Hannah Marie Moore

Murray State Theses and Dissertations

Anthropogenic activities have led to degradation in streams throughout much of Western North America. In particular, cattle grazing has led to a loss of riparian vegetation resulting in higher water temperatures and an increase in nutrient runoff. The effects of degradation on food quality and quantity for aquatic consumers could have large implications for stream communities. Since omnivores feed at multiple trophic levels, they may be resilient to altered food webs, which may allow them to stabilize communities in degraded environments where resources have been reduced. To test the hypothesis that omnivores positively impact community stability in degraded conditions, I …

Anthropogenic Influences On The Decline, Restoration, And Eco-Evolutionary Dynamics Of Lake Superior’S Coaster Brook Trout, Austin Johnson

Dissertations, Master's Theses and Master's Reports

The coaster brook trout is a life history variant of the brook trout (Salvelinus fontinalis) that is characterized by either lake residency or migration between stream and lake habitats. Coaster brook trout were once widespread throughout Lake Superior and its tributaries, but populations declined sharply in the late 19^th and early 20^th centuries. Historically, brook trout were a popular target of recreational and subsistence fishing in the Lake Superior basin, and it has been hypothesized that angling pressure combined with multiple forms of industrial development are what drove the coaster brook trout’s decline. In the mid …

Wetland Restoration Efforts Result In Increasing Phylogenetic Diversity, Nicholas T. Foster

Graduate Research Theses & Dissertations

Over the course of ecological restoration efforts, it has been observed that, despite restoration activities, species richness sometimes declines in a given habitat. While this response can be interpreted to mean that restoration activities are ineffective, other measures known as Phylogenetic Diversity Metrics can show that the community is actually becoming more diverse. Utilizing plant inventories collected as transect data from 1992-2021 of five wetland sites under various types of restoration in northern Illinois, a regional wetland community phylogeny was assembled. The community phylogeny was then analyzed for phylogenetic diversity measures through this 30-year period across the five sites. Additionally, …

Exploring The Host Range, Impacts, And Distribution Of Black Rot Disease On Alliaria Petiolata, Gabriela Ivette Harney-Davila

Browse all Theses and Dissertations

Garlic mustard is an invasive Eurasian biennial spreading in deciduous forests of North America. Garlic mustard plants in Ohio can be infected with a strain of Xanthomonas campestris, the causal agent of black rot disease in brassicas. I examined variation in susceptibility to X. campestris among garlic mustard populations, several native wild species, and agricultural crop varieties. Twenty-four garlic mustard populations were universally susceptible to X. campestris, though disease severity varied. Cardamine concatenata and Cardamine diphylla were susceptible but can phenologically escape infection in the field. Of the 14 agricultural crops tested, three cultivars (Raphanus sativus, Brassica rapa var. Rapa …