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Bobcat Abundance And Habitat Selection On The Utah Test And Training Range, Kyle David Muncey Dec 2018

Bobcat Abundance And Habitat Selection On The Utah Test And Training Range, Kyle David Muncey

Theses and Dissertations

Remote cameras have become a popular tool for monitoring wildlife. We used remote cameras to estimate bobcat (Lynx rufus) population abundance on the Utah Test and Training Range during two sample periods between 2015 and 2017. We used two statistical methods, closed capture mark-recapture (CMR) and mark-resight Poisson log-normal (PNE), to estimate bobcat abundance within the study area. We used the maximum mean distance moved method (MMDM) to calculate the effective sample area for estimating density. Additionally, we captured bobcats and estimated home range using minimum convex polygon (MCP) and kernel density estimation (KDE) methods. Bobcat abundance on the UTTR …


Characterizing Spatial And Temporal Changes And Driving Factors Of Groundwater And Surface-Water Interactions Within The Mississippi Portion Of The Mississippi Alluvial Plain, Courtney Killian Aug 2018

Characterizing Spatial And Temporal Changes And Driving Factors Of Groundwater And Surface-Water Interactions Within The Mississippi Portion Of The Mississippi Alluvial Plain, Courtney Killian

Theses and Dissertations

The Mississippi Alluvial Plain, a robust agricultural region in the South-Central United States, provides commodities across the United States and around the world. Water for irrigation, which is necessary due to irregular rainfall patterns during the growing season, is withdrawn largely from the Mississippi River Valley Alluvial aquifer, one of the most intensely used aquifers in the United States. The groundwater-dependent region has observed recent declines in groundwater and streamflow levels, raising concerns about the availability and use of fresh-water resources. Declining water levels have prompted investigation into the current understanding of groundwater and surface-water interaction. Previous research does not …


An Ecological And Distributional Analysis Of Great Basin Bristlecone Pine (Pinus Longaeva), Gregory Watson Taylor Aug 2018

An Ecological And Distributional Analysis Of Great Basin Bristlecone Pine (Pinus Longaeva), Gregory Watson Taylor

Theses and Dissertations

Understanding the impacts of climate change is critical for improving the conservation and management of ecosystems worldwide. Ecosystems vary along a precipitation and temperature gradient, ranging from tropical jungles to arid deserts. The Great Basin is a semi-arid eco-region that is found within the western United States. Plant communities within the Great Basin range from sagebrush valleys to sub-alpine conifer forests found at high elevation areas. It is predicted that the Great Basin will experience prolonged periods of drought, more intense fires, and greater variability in average annual and monthly precipitation, all in response to changes in climate patterns. At …


Questing Activity Of Cattle Fever Tick Larvae, Rhipicephalus (Boophilus) Microplus (Acari: Ixodidae): Environmental Influences And Implications For Control In South Texas, Brenda Leal Aug 2018

Questing Activity Of Cattle Fever Tick Larvae, Rhipicephalus (Boophilus) Microplus (Acari: Ixodidae): Environmental Influences And Implications For Control In South Texas, Brenda Leal

Theses and Dissertations

Questing ticks ascend stems, leaves, or rocks, extend their front legs, and wait poised for attachment to a passing host. Ixodid ticks have four developmental stages. Because ticks detach and molt between stages most ticks require three separate hosts to complete their lifecycle. Three-host ticks quest for a new host between each stage, whereas a few specialist tick species remain on and thus require only a single host. These one-host ticks only quest for hosts as larvae. As much as 90% of the life cycle may consist of questing when hosts are scarce. Most of the literature on questing relates …


The Effects Of Common Forest Management Practices On Community Structure In A Southern Pine Forest, Donald Paul Chance May 2018

The Effects Of Common Forest Management Practices On Community Structure In A Southern Pine Forest, Donald Paul Chance

Theses and Dissertations

Planted pine (Pinus spp.) comprises nearly 10% of the total land cover in the state of Mississippi. Often, understory structure is limited in this system. Thus, managers use a variety of management practices to improve understory biomass and structure. I assessed the impacts of common forest management practices (canopy reduction, prescribed fire, and selective herbicide application) and their combined effects on aspects of community structure. More specifically, I assessed impacts of disturbance intensity on non-native plant invasions, and evaluated how microscale vegetation characteristics influenced use by white-tailed deer (Odocoileus virginianus) and wild turkey (Mealagris gallopavo). Combining canopy reductions with prescribed …


Culture Techniques And Evaluation Of Snail Consumption By Black Buffalo Ictiobus Niger, Emmet Liam Guy May 2018

Culture Techniques And Evaluation Of Snail Consumption By Black Buffalo Ictiobus Niger, Emmet Liam Guy

Theses and Dissertations

Black Buffalo Ictiobus niger are a catostomid species native to the Mississippi River Basin with declining populations. Aquaculture is a common component of recovery plans, however little information is published on catostomid culture methods. This study developed culture techniques for Black Buffalo including tank acclimation, induced spawning, larval rearing, and protein requirements. Fish needed a lengthy acclimation (> 2 months) to reduce signs of stress. After, an induced-spawning protocol was described with gonadotropin-releasing hormone analogue. Swim-up fry did not readily consume zooplankton at first feeding but began selecting for cladocerans one week after stocked in a rearing pond. The juvenile …


Estimating Feral Swine Abundance And Their Effects On Native Wildlife In The Mississippi Alluvial Valley, Matthew Ryan Ivey May 2018

Estimating Feral Swine Abundance And Their Effects On Native Wildlife In The Mississippi Alluvial Valley, Matthew Ryan Ivey

Theses and Dissertations

Feral swine (Sus scrofa) are an invasive species in the Mississippi Alluvial Valley (MAV). They cause millions in damage annually to agriculture, and likely negatively affect native wildlife species. Using camera traps, I monitored 36 forest patches within the MAV to assess the effects of swine invasions on native wildlife species richness. I also modified the double-observer point count technique into a new method for estimating swine abundance with camera traps. Feral swine suppressed native vertebrate richness by 26% when compared to uninvaded patches. I validated the new double-observer technique by determining if it could detect an abundance-area relationship in …


Small Mammal Diversity, Rattlesnake Demographics, And Resource Utilization In The Great Basin: Implications For Management And Stable Isotope Proxies, Bryan T. Hamilton Apr 2018

Small Mammal Diversity, Rattlesnake Demographics, And Resource Utilization In The Great Basin: Implications For Management And Stable Isotope Proxies, Bryan T. Hamilton

Theses and Dissertations

Plant carbon isotopes were used to track assimilation of riparian resources by small mammals. Voles and shrews derived significant portions of their carbon from riparian vegetation. Deer and harvest mice were abundant in riparian habitat but assimilated little riparian vegetation indicating that the riparian corridor provided resources other than food. This is first use of stable carbon isotopes to trace riparian resources into a vertebrate community. Conifer encroachment in sagebrush ecosystems negatively affects many wildlife populations. Conifer removal is recommended across millions of hectares in the Great Basin. However the effects of conifer encroachment and conifer removal are unknown for …


Characterization Of Ambient Noise, Rachel C. Ramirez Mar 2018

Characterization Of Ambient Noise, Rachel C. Ramirez

Theses and Dissertations

An Air Force sponsor is interested in improving an acoustic detection model by providing better estimates on how to characterize the background noise of various environments. This would inform decision makers on the probability of acoustic detection of different systems of interest given different levels of noise. Data mining and statistical learning techniques are applied to a National Park Service acoustic summary data set to find overall trends over varying environments. Linear regression, conditional inference trees, and random forest techniques are discussed. Findings indicate only sixteen geospatial variables at different resolutions are necessary to characterize the first ten ⅓ octave …


Learning To See The Forest For The Corn: Establishing Sense Of Place And Community In A Field-Based Ecology Course For Pre-Service Educators, Michelle Edgcomb Friday Feb 2018

Learning To See The Forest For The Corn: Establishing Sense Of Place And Community In A Field-Based Ecology Course For Pre-Service Educators, Michelle Edgcomb Friday

Theses and Dissertations

In this dissertation grounded theory techniques were used to characterize pre-service educators’ experiences in a semester-long, field-based ecology course. Through participation in a citizen science project, participants formed a community of practice that extended their conceptions of themselves as ecology students and scientists. Extended field experiences in a variety of local ecosystems contributed to the development of a sense of place. Paired fieldwork with lecture aided their developing ecological literacy and their understanding of place-based pedagogy. All of these combined to support their growing understanding of their role in field-based ecology education. Lack of background in ecology and ecology pedagogy …


The Effect Of Sexually Objectifying Media And Social Threat On Sexual Coercion, Carissa Ann Malevich Jan 2018

The Effect Of Sexually Objectifying Media And Social Threat On Sexual Coercion, Carissa Ann Malevich

Theses and Dissertations

Sexual aggression researchers have struggled to find a specific profile of individuals likely to become sexually aggressive (Abbey, 2005). As most of the research has focused on internal personal characteristics, some researchers have called for more research into external or situational factors that may increase the likelihood for men to become sexual perpetrators (Farris, Viken & Treat, 2010). Thus, the current investigation sought to explore the impact of two promising external factors, sexually objectifying media and social threat, on sexual coercion proclivity. Sexual coercion is a much lesser studied form of sexual aggression but is very common and often normalized …


Evaluation Of Movements And Habitat Use Of Suburban Striped Skunks (Mephitis Mephitis) In The Northern Great Plains To Inform Rabies Management, Anna Schneider Jan 2018

Evaluation Of Movements And Habitat Use Of Suburban Striped Skunks (Mephitis Mephitis) In The Northern Great Plains To Inform Rabies Management, Anna Schneider

Theses and Dissertations

Few studies have investigated the ecology of urban striped skunks (Mephitis mephitis) despite their role as a primary rabies vector species paired with an ability to thrive in these landscapes. Our aim was to obtain baseline ecological information with an emphasis on spatial ecology of urban striped skunks in the Northern Great Plains region that is missing in the literature. This information, such as home range, nightly movements, habitat selection, and denning behavior is important for informing rabies management decisions such as the placement of oral rabies vaccine (ORV) baits. We used radio telemetry equipment to track 22 (4M, 18 …


From Rhetoric To Response: Climate Change, Conflict, And Development In Karamoja, Uganda, Daniel Abrahams Jan 2018

From Rhetoric To Response: Climate Change, Conflict, And Development In Karamoja, Uganda, Daniel Abrahams

Theses and Dissertations

This dissertation addresses the broad question: How do the discourses of climate change and conflict travel across time and space to become policy, programming, and ultimately a development initiative that exist on the ground? To answer this question, I broke the research into three separate papers. The first examines how the US policy community approaches, understands and seeks to address the discourses of climatesecurity. The second examines the ways in which climate change affects conflict outcomes in Karamoja, Uganda. And the third, using the efforts of Mercy Corps in Karamoja as a case study, examines the realities and opportunities in …


Prescription Drug Monitoring Programs And Opioid Poisoning: Evaluating The Impact Of Prescriber Use Mandates On Prescription Opioid Poisoning Emergency Department Visits, Sarah Almanie Jan 2018

Prescription Drug Monitoring Programs And Opioid Poisoning: Evaluating The Impact Of Prescriber Use Mandates On Prescription Opioid Poisoning Emergency Department Visits, Sarah Almanie

Theses and Dissertations

Introduction: Prescription drug monitoring programs (PDMPs) are one strategy established to curb the prescription opioid abuse epidemic. Prescriber use mandates has emerged as a promising practice to increase PDMPs impact on prescription opioid abuse; however, evidence of its effectiveness has not yet been established. Kentucky was the first state to implement comprehensive prescriber use mandates in July 2012.

Objective: To assess the relationship between prescriber use mandates policy and emergency department (ED) visits related to prescription opioid poisoning among adults in Kentucky and

North Carolina. Secondary aim: to evaluate the economic impact of prescriber use mandates in Kentucky.

Methods: A …


Climate Metric Coherence: Stationarity Of The Relationships Between North Pacific Climate Indices And Ecological Processes In The Gulf Of Alaska, Michael Opiekun Jan 2018

Climate Metric Coherence: Stationarity Of The Relationships Between North Pacific Climate Indices And Ecological Processes In The Gulf Of Alaska, Michael Opiekun

Theses and Dissertations

The Pacific Decadal Oscillation (PDO) has been used to characterize the dominant basin-scale climate variability, in the North Pacific. The PDO index has been correlated to Pacific salmon (Oncorhynchus spp.) population dynamics in the Gulf of Alaska (GOA) during the late 1900s, but the stationarity of the statistical relationships between salmon production and the basin-scale index (and between the regional physical processes and the basin-scale index) has not been quantified. A change in the relationship between the PDO and salmon catches has been noted during the late 1980s, motivating further investigation of variability in climate and ecosystem properties during this …


Application Of Non-Targeted Volatile Metabolomics In Plant Pathology, Jinyan She Dec 2017

Application Of Non-Targeted Volatile Metabolomics In Plant Pathology, Jinyan She

Theses and Dissertations

Our study focuses on the application of volatile metabolomics and chemometrics in plant pathology. Specifically, volatile metabolites or volatile organic compounds (VOCs) from the American chestnut tree (Castanea dentata) and its pathogenic fungus Cryphonectria parasitica have been investigated. The American chestnut was once a dominant tree species in the eastern forests of the United States. However, it was nearly devastated by the fungal pathogen C. parasitica. The loss of this tree species has significantly impacted the ecosystem. Therefore, preservation and restoration of American chestnut are crucial. Chapter one provides an overview of mass spectrometry based volatile metabolomics and their implementation …


Distributions Of Polychaetes As A Function Of Sediment Composition In A Subtropical Lagoon, Anthony William Cox Oct 2017

Distributions Of Polychaetes As A Function Of Sediment Composition In A Subtropical Lagoon, Anthony William Cox

Theses and Dissertations

Fine-grained organic-rich sediments (FGORS) in the Indian River Lagoon (IRL), Florida, the human activities and nutrient inputs and have a varied composition, including water content, silt-clay content, and organic matter. When these constituents reach, by weight, 75%, 60% dry, and 10% dry, respectively, this is sometimes referred to as IRL “muck”. Many polychaetes inhabit the benthic sediments of estuaries and must tolerate various degrees of FGORS. The Cox IRL Muck Index (CMI) is proposed as a mechanism for determining the organic sediment tolerances of infaunal species in a simple and direct manner. IRL muck will have a minimum CMI of …


Advancing Our Understanding Of The Edwardsiella, Stephen Ralph Reichley Aug 2017

Advancing Our Understanding Of The Edwardsiella, Stephen Ralph Reichley

Theses and Dissertations

Diseases caused by Edwardsiella spp. are responsible for significant losses in wild and cultured fishes around the world. Historically, Edwardsiella tarda has been considered the most phenotypically and genotypically heterogeneous member of the genus. Investigations into intraspecific variability of E. tarda demonstrated isolates previously classified as E. tarda actually represent three genetically distinct yet phenotypically ambiguous groups, leading to the adoption of E. piscicida and E. anguillarum as discrete taxa. Current genomic investigations have demonstrated significant differences between these organisms. To this end, real-time quantitative PCR assays were developed to quickly and accurately detect the pathogens in pond water, fish …


Response To Drought Of A Stream Fish Assemblage In A High Elevation Stream In The Intermountain West, Richard M. Simkins Jul 2017

Response To Drought Of A Stream Fish Assemblage In A High Elevation Stream In The Intermountain West, Richard M. Simkins

Theses and Dissertations

One of the most influential disturbances for stream fish assemblages is large-scale declines in flow caused by periods of drought. Although stream characteristics are known to influence the response of stream fishes to drought, we asked if ecological traits of stream fishes determine, in part, their population level response to drought. To test for ecological trait-based responses to drought in a stream fish assemblage, we quantified species abundances over a period of 5 years that represented a wet to dry period. We sampled stream fishes in Yellow Creek, Wyoming, USA, a high elevation stream dependent on snow-storage for most of …


Causes And Consequences Of Individual Phenotypic Differences In Brachyuran Crabs With A Focus On Behavior, Benjamin A. Belgrad May 2017

Causes And Consequences Of Individual Phenotypic Differences In Brachyuran Crabs With A Focus On Behavior, Benjamin A. Belgrad

Theses and Dissertations

Individual variation defines almost every morphological, physiological, and behavioral aspect of populations and is a fundamental component of many ecosystem processes. Recent work indicates that accounting for these individual differences can enhance our ability to predict community responses to environmental disturbances which is becoming increasingly important in an era of extraordinary global change. However, our understanding of how different individual characteristics are connected to each other and governed by the environment remains limited.

This study sought to evaluate the relationship between individual behavior, physiological condition, and local habitat for Brachyuran crabs as well as the subsequent strength of their predator-prey …


Radioactive Contamination Of Natural Biological Systems: Oxidative Balance And Genetic Stability, Daniel Einor Jan 2017

Radioactive Contamination Of Natural Biological Systems: Oxidative Balance And Genetic Stability, Daniel Einor

Theses and Dissertations

The global demand for nuclear energy grows, and so do the risks of an accidental release of nuclear products into the environment. Therefore, understanding the health and ecological effects of contamination by radionuclides should be of great interest for biomedical specialists and the public. Empirical studies unequivocally show that high doses of ionizing radiation (IR) shift the redox-balance of many biological systems and increase the rates of genetic errors. However, the effects of chronic low doses of radiation vary significantly between tissues and between species. The present dissertation comprises the results of experimental and meta-analytical research of a variety of …


Association Between Diabetes And Cancer In Indian And Us Populations Using Longitudinal Study Design, Shraddha S. Vyas Jan 2017

Association Between Diabetes And Cancer In Indian And Us Populations Using Longitudinal Study Design, Shraddha S. Vyas

Theses and Dissertations

Background: There is growing evidence of association between diabetes and cancer. No studies have been conducted in India evaluating this association. With the current epidemiologic, nutritional and economic transition in India, it becomes extremely important to examine this association in an Indian population. Additionally, difference in association exists based on different cancer subtypes. Research has shown that diabetes is associated with an increased risk of colorectal cancer. However most of these studies suggest detection bias to be one of the probable reasons for this association. Additionally, the common risk factors shared by both these conditions are considered to one of …


Spatial And Trophic Niche Specialization In Castor Canadensis, Robert Antonio Francis Dec 2016

Spatial And Trophic Niche Specialization In Castor Canadensis, Robert Antonio Francis

Theses and Dissertations

The Hutchinsonian niche is the n dimensional hyper volume that allows for the persistence of a species. Castor canadensis, a large semi-aquatic rodent, is an ecosystem engineer and often a keystone species for many ecosystems. I examined the effect of multiple spatial scales on hierarchical habitat selection byC. canadensis using presence-only modeling techniques. I also determined individual trophic niche specialization in C. canadensis utilizing stable isotope analysis. I concluded that C. canadensis displayed scale independent habitat selection when comparing landscape and fine spatial scales. Individual trophic niche specialization occurred in colonies of the same resource availability. Also, individual trophic niches …


Natural Population Dynamics Of Rock Iguanas In The Bahama Archipelago, Giuliano Colosimo Dec 2016

Natural Population Dynamics Of Rock Iguanas In The Bahama Archipelago, Giuliano Colosimo

Theses and Dissertations

Understanding whether groups of individuals represent a single panmictic gene pool, or multiple genetically structured populations across a species range should aid in predicting whether specific conservation strategies would be more or less effective for species preservation. Further, contrasting the population structures of multiple coexisting taxa could foster an even deeper understanding of evolutionary divergence among demes and potentially even suggest local adaptation in the form of tight coevolutionary relationships. Finally, the analysis of population dynamics within small and isolated populations could improve our understanding of the relative importance that different evolutionary mechanisms have in predicting population persistence in the …


Interconnectedness, Complicity And Ambiguity: Reading With Dark Ecology, Rachel Dene Whipple Jul 2016

Interconnectedness, Complicity And Ambiguity: Reading With Dark Ecology, Rachel Dene Whipple

Theses and Dissertations

There are many aspects of ecological thinking. When reading texts through a lens of dark ecology, certain conflicts that arise from the imposition of human expectations on natural systems are revealed. These include interconnectedness, complicity, and ambiguities. Within a system, boundaries are contingent and transitory. Beginnings and ends are gradual, not definite. Ecological systems change over time, but it is a category error to imagine that change represents progress or to assume a teleological purpose. While there are hierarchies of power, and different roles, no species is, ecologically speaking, more advanced than another. Ecological criticism focuses on interconnectedness, complicity, and …


From Near And Far: Utilization Of In-Situ And Remotely Sensed Satellite Data From Nasa And Noaa, Jessica Rochelle Price Sutton Jun 2016

From Near And Far: Utilization Of In-Situ And Remotely Sensed Satellite Data From Nasa And Noaa, Jessica Rochelle Price Sutton

Theses and Dissertations

Satellite remote sensing observations have been used for numerous studies to better understand physical and biological properties over varying spatial and temporal scales. Depending on the satellite and sensor, the satellite-derived observations can provide high spatial and temporal resolution for many important physical and biological variables. While there are many limitations in utilizing satellite remote sensing products, there are also many advantages. This dissertation investigates three different applications for satellite remote sensing products to address climatological and ecological concerns. This dissertation is motivated by two overall research questions: (1) How can satellite remote sensing products be used to address important …


Breeding And Brood Rearing Ecology Of Mottled Ducks In The Ashepoo, Combahee, And Edisto Rivers Basin, South Carolina., Molly Rebecca Kneece May 2016

Breeding And Brood Rearing Ecology Of Mottled Ducks In The Ashepoo, Combahee, And Edisto Rivers Basin, South Carolina., Molly Rebecca Kneece

Theses and Dissertations

Mottled ducks (Anas fulvigula) are a non-migratory waterfowl species endemic to the western Gulf Coast, with a separate, genetically distinct subspecies (A. fulvigula fulvigula) occurring in peninsular Florida. Birds from Texas, Louisiana, and Florida were released in coastal South Carolina from 1975-1983, and banding data suggest an expanding population. I monitored 72 mottled duck nests and captured and radio-marked 196 pre-breeding and nesting females between 2010 and 2014 to study breeding ecology of these birds in the Ashepoo, Combahee, Edisto Rivers Basin. Nest success averaged 12% and varied with vegetation height and year. Indicated breeding pair surveys revealed breeding mottled …


Assessment Of Early Successional Arthropod And Breeding Bird Response To Intercropping Switchgrass Within An Intensively Managed Loblolly Pine Forest, Craig Daniel Marshall May 2016

Assessment Of Early Successional Arthropod And Breeding Bird Response To Intercropping Switchgrass Within An Intensively Managed Loblolly Pine Forest, Craig Daniel Marshall

Theses and Dissertations

Loblolly pine (Pinus taeda) plantations are a common land use of the southeastern United States that have the potential to function as a source of cellulosic biomass for biofuel production. A novel land use practice of intercropping switchgrass (Panicum virgatum) between planted loblolly pines has been developed as a potential method of cellulosic biomass production. I evaluated response of arthropods and breeding birds to intercropping switchgrass within loblolly pine plantations compared to typically managed pine plantations. I detected 13 arthropod orders and 44 breeding bird species during 2014 – 2015. Intercropping switchgrass reduced arthropod diversity and evenness, with richness not …


U.S. Population Change: The Roles Of Amenities And Transportation, Xuan Zhou May 2016

U.S. Population Change: The Roles Of Amenities And Transportation, Xuan Zhou

Theses and Dissertations

Studying the spatial distribution and redistribution of population has long been a major concern of demography, because population changes can reflect deep and massive social changes. For decades, the major population change was the moving of people from rural to urban regions. However, with the advancement of transportation and information technology, many new regions have become more attractive to people, such as small and new metropolitan, nonmetropolitan, suburban, and rural areas. Traditional migration and population redistribution studies emphasize economic and social factors. Relatively little attention is paid to how natural amenities and transportation affect changes of population size and net …


The Spatial And Temporal Distribution Of Residential Burglary In Brownsville, South Texas, Sonia Figueredo May 2016

The Spatial And Temporal Distribution Of Residential Burglary In Brownsville, South Texas, Sonia Figueredo

Theses and Dissertations

The study utilized existing theories, including the pattern theory/environmental criminology, and the routine activities and lifestyles theories and also existing technology to examine the spatial and temporal patterning and variations in residential burglary, the processes that produce this type of burglary, and its incidence rates among the twelve law enforcement zones (PPZ’s) in the South Texas border city of Brownsville from 2006 to 2014. The data and information for the thesis were the raw Brownsville Police Department (BPD) data on residential burglary incidents that showed the addresses where, and the times, days, months and years when the incidents occurred. The …