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Unraveling The Behavioral Ecology Of The Western Diamond-Backed Rattlesnake (Crotalus Atrox) Through The Lenses Of Personality, Predator-Prey Interactions, And Crypsis, Oceane Da Cunha

Open Access Theses & Dissertations

To thrive in an environment, individuals need to be able to forage efficiently and acquire mates. These resources are limited, and their acquisition depends upon the energy and time an individual chooses to allocate to each activity and the environmental conditions, leading to behavioral trade-offs. Different species, or even different individuals within the same population, respond to these trade-offs by employing contrasting strategies, leading to differential life-history outcomes. The overarching goal of this dissertation is to gain a better understanding of the trade-offs cryptic ambush mesopredators are facing using the western diamond-backed rattlesnake (Crotalus atrox) as a model species. Each …

The Ecology And Genetic Diversity Of Buckleya Distichophylla (Santalaceae), Montana Hill, Conley K. Mcmullen

Masters Theses, 2020-current

Piratebush (Buckleya distichophylla) is a native, rare, shrub found along the Blue Ridge mountains in North Carolina, Virginia, and Tennessee. Research on its ecology and genetic diversity is limited due to its rarity; only one population on Poor Mountain has been studied extensively in the past. To determine if there are ecological differences between populations of B. distichophylla, research on sex distribution, floral visitors, individual length, leaf area, and amount of light that reached each specimen were conducted and then compared between a population located on Dragon’s Tooth Trail and a population on Poor Mountain, both located …

Evaluation Of Avian Use Of Agricultural Cover Crops During The Winter, Migration Stopover, And The Breeding Season In Tennessee, Brittany Panos

Masters Theses

The U.S. Department of Agriculture Natural Resources Conservation Service administers the cover crop program to provide technical and financial assistance to agricultural producers to sow herbaceous plant seeds to establish cover crops to protect agricultural fields from soil erosion during the non-growing season (late fall through spring). Soil retention and water quality benefits have been documented, but potential benefits for avian wildlife remain largely unknown. I used line-transect avian and vegetation surveys to examine use of cover crop fields by birds during the non-breeding period (winter), migration, and the breeding season. I compared avian use of cover crop fields with …

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 …

To Melt, Huanzhe Hu

Masters Theses

This thesis focuses on the need for a reevaluation of the relationship between humans and nature in the face of the current ecological crisis. The author argues that the dominant anthropocentric orientation, which sees nature as a resource to be exploited for human benefit, has led to over extraction and resource abuse, disrupting the balance of ecosystems. Instead, the author suggests adopting an ethical framework based on mutual understanding and appreciation, breaking the "hunter's gaze" and fostering empathy for non-human life forms. This thesis also explores the potential for new forms of communication and engagement with nature, such as through …

The Materiality Of Waka And Ikebana: Locating Ecological Relationships Between Delivery And Arrangement, Bianca Oliveira

All HCAS Student Capstones, Theses, and Dissertations

Rhetorical applications of delivery and arrangement have grown to reflect the global interconnectedness of cultures, bodies, and material objects. Informed by rhetorical and ecological approaches to delivery and arrangement (Edbauer Rice; Lambke;), this project performs a rhetorical and ecological analysis of ikebana (Japanese flower arrangements) and waka (Classical Japanese poetry) by Meishu-Sama and Saigyō Hōshi. Waka and ikebana, as compositional modes, reveal an interpolation of delivery and arrangement that invites both composer and audience to embody nature. As such, this project examines the visual-material and sonic rhetorics of waka and ikebana in order to discover how delivery and arrangement affect …

Trophic Ecology And Mercury Concentrations Of Canary Rockfish (Sebastes Pinniger) In The California Current System, Michaela M. Melanson

Master's Theses

Canary rockfish are a profitable fishery resource that has failed and successfully recovered in the 21st century. This study aimed to evaluate their trophic ecology through stomach content and stable isotope analysis and relate these to their mercury concentrations, biological traits, and environmental conditions. Canary rockfish consume mostly krill and teleosts with their geographic location affecting the proportion of prey items, suggesting regional environmental effects: chlorophyll-a, relief, port, and depth impact dietary choices. Mean ??13C values (-17.18 ± 0.54) significantly increased in individuals residing in deeper depths, higher latitudes, higher productivity, and higher temperatures, and in sexually mature individuals. Mean …

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 …

Competing Behaviors Of Thermoregulation And Ambush Foraging In The Timber Rattlesnake (Crotalus Horridus Horridus): A Mechanistic Assessment Of Thermal Conduction, Larry K. Kamees

Graduate Theses and Dissertations

The interaction between the biophysical environment and ectotherm morphology elicits behaviors designed to maintain internal body temperature (Tb) within a range that promotes physiological functions. The short-term requirements of mass (energy requirements) and heat balance are subject to tradeoffs imposed by the organisms current physiological (heat and mass budgets) and environmental (biophysical, demographic, social, and predation) constraints and available resources. In temperate forests, extreme temperatures are common in summer even with intermittent sun exposure due to dense canopy cover. In Spring and Fall, temperatures can range from below freezing to 35 ℃ in 24 hrs. An ambush predator like the …

Distribution Patterns Of The Invasive Mussel Arcuatula Senhousia In Mission Bay, San Diego, California: Effects Of Sediment Grain Size And Byssus Thread Production On Predation, Samantha Ahlman

Theses

The ability of bivalves to avoid predation by using defensive behaviors such as burrowing and byssus production may vary depending on the sediment characteristics of a given habitat. The varying sediment characteristics that change with water velocity within estuaries may influence the distribution of bivalves and limit them to areas that optimize their ability to defend against predators. We examined the distribution patterns of the invasive Asian date mussel Arcuatula senhousia relative to the sediment grain size distribution in Mission Bay, an urban estuary located in San Diego, California, USA. Mussels and sediment were collected using an Ekman grab at …

Detection, Occupancy, Abundance, And Mercury Accumulation Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Texas, David Rosenbaum

Electronic Theses and Dissertations

Land use practices and physical alterations of ecosystems result in habitat loss and fragmentation, while chemical alterations, such as pollutant input, reduce habitat quality and health of exposed organisms. Here, I investigated the effects of watershed- and local-scale environmental variables on the occupancy, abundance, and mercury accumulation of a threatened aquatic species (Macrochelys temminckii, i.e., alligator snapping turtle) within the southwestern periphery of its distribution. Hierarchical modeling suggested the distribution of the species is more affected by watershed-scale land-cover than local habitat, and provided a baseline estimate of average species abundance across its range in eastern Texas. Abundance …

Research Handling Effects On Stress Hormones, Blood Parameters, And Heart Rate In Juvenile Northern Elephant Seals (Mirounga Angustirostris), Lauren A. Cooley

Master's Theses

Wildlife researchers must balance the need to safely capture and handle their study animals to sample tissues, collect morphological measurements, and attach dataloggers while simultaneously ensuring their results are not confounded by stress artifacts caused by handling. To determine the physiological effects of research activities including chemical immobilization, transport, instrumentation with biologgers, and overnight holding on a model marine mammal species, I collected hormone, blood chemistry, hematology, and heart rate data from 19 juvenile northern elephant seals (Mirounga angustirostris) throughout a translocation experiment. Across my six sampling timepoints, cortisol and aldosterone data revealed a moderate hormonal stress response to handling …

Microbial Communities Hosted By Carnivorous Pitcher Plants: Diversity, Recruitment, Functions And Succession In Sarracenia Purpurea Microbiomes, Jacob Jeffrey Grothjan

Theses and Dissertations

The pitcher plant Sarracenia purpurea supplements nutrient acquisition through carnivory, capturing insect prey which are digested by a food web community of eukaryotes and bacteria. Analysis of both bacterial and eukaryotic diversity, and an understanding of bacterial recruitment into pitchers and succession of bacterial and eukaryotic communities over time have not been well explored. This thesis presents three studies designed to address these gaps using field sampling and manipulative greenhouse experiments. Study I compared bacterial and eukaryotic composition and diversity of pitcher communities within and between populations of plants in two distinct wetland habitats. Genetic sequence analysis revealed an underappreciated …

Community Perceptions And Aesthetic Valuation Of Remediation Gardens, Rachel Bechtold

Graduate Theses and Dissertations

Creating successfully remediated landscapes may rely on both natural resources and human perception in landscape design. Urban areas present a dynamic environment wherein communities and nature compete for resources and space. This dissertation study was designed to better understand aesthetic perceptions of native plants capable of land remediation in midwestern communities. Findings from this study show the importance of aesthetic perceptions of stakeholders towards rehabilitated landscapes and the importance of organizing indicators for future design decisions in an interdisciplinary fashion. Recommendations include continued evaluation of aesthetic perceptions for plant species in urban landscapes and modeling a more consistent framework for …

The Effects Of Urbanization On The Avian Gut Microbiome, Mae Berlow

Doctoral Dissertations

The gut microbiome influences and is influenced by the host, and can affect the host organism by contributing to health, development and immunity. Similarly, the host can influence this community; it’s makeup can vary with host species, locality, diet, social stressors, and environmental stressors. Some of these environmental stressors have arisen due to human-induced rapid environmental change, like urbanization. The physiology and behaviors of organisms that are able to persist in urban environments are often different from their non-urban congeners. Nutrition, development, and immunity—all of which are affected by the gut microbiome—are important factors that can determine survival in urban …

Acoustic Analysis Of Saproxylic Arthropod Diversity In North And Central American Pine Forests, Kristy Marie Mcandrew

Theses and Dissertations

Biodiversity of arthropods living in dead wood is often understudied despite their potential effects on ecological processes such as wood decomposition and nutrient cycling. More time-efficient and less destructive methods are needed to study these saproxylic organisms to fully understand their global diversity. Because ecoacoustic methods have never been applied to saproxylic communities before, field and analytical methods such as waveguides, and soundproofing were developed, tested, and optimized. After developed methods were implemented in the field, Pearson's correlation tests were conducted to compare ecoacoustic index performance to traditional biodiversity indices. We found five significant correlations, all of which occurred at …

Creating A Comprehensive Western American/Canadian Fire Dataset, 1880-2018, Katherine Welch

WWU Graduate School Collection

The currently available fire-history data of Western North America (US/Canada) available for geographic and other analyses is largely piecemeal and difficult to find. Data from before the 1980s is scattered among many sources and held by a plethora of different agencies. The aim of this project was to change that daunting reality and provide a single dataset that would fill that data gap and make doing research on and mapping of fires in the late 19th and early 20th centuries more accessible.

This data encompasses 138 years (1880 - 2018), 12 US states, three Canadian provinces and two Canadian territories. …

Roles And Interaction Of Blow Flies (Diptera: Calliphoridae) And Introduced Fire Ants (Hymenoptera: Formicidae: Solenopsis Invicta And S. Invicta X Richteri) In Carrion Decomposition In The Southeastern United States, Grant De Jong

Theses and Dissertations

Invasive fire ants (Solenopsis invicta and its hybrid with S. richteri) have been reported from carrion in the southeastern United States and are considered a part of the succession community. Alteration of ecological processes by fire ants could affect forensic interpretation of entomological data; therefore, I conducted studies to investigate the relative roles and interactions of fire ants and blow flies in carrion decomposition. The blow fly species composition in Mississippi has not been studied since 16 species were reported in 1983. Specimens from the Mississippi Entomological Museum were used to update the checklist of the blow flies of Mississippi …

Analyzing The Von Neumann Entropy Of Contact Networks, Thomas J. Brower

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

When modeling the spread of disease, ecologists use ecological or contact networks to model how species interact with their environment and one another. The structure of these networks can vary widely depending on the study, where the nodes of a network can be defined as individuals, groups, or locations among other things. With this wide range of definition and with the difficulty of collecting samples, it is difficult to capture every factor of every population. Thus ecologists are limited to creating smaller networks that both fit their budget as well as what is reasonable within the population of interest. With …

Floodplain Forest Regeneration Dynamics In The Lower Mississippi River Alluvial Valley, Whitney Anne Kroschel

LSU Doctoral Dissertations

Floodplain forest species diversity is driven, in part, by variation in disturbance regime. Flood patterns create heterogeneity in microsite quality from small differences in elevation across a floodplain which, in turn, influence flood timing and duration. Differences in species’ regeneration niches in relation to hydrologic patterns can account for long-term coexistence of various species. In the past century floodplain forests have exhibited a wide range of changes in stand development and species composition as a result of altered hydrology in rivers and floodplains. I evaluated the role of regeneration in floodplain forest systems of the Lower Mississippi River Alluvial Valley …

The Gut Microbiota Of A Wild American Black Bear (Ursus Americanus) Population, Sierra Gillman

All NMU Master's Theses

The gut microbiome (GMB), the mutualistic microbial communities located in the gastrointestinal tract (GIT), has co-evolved in vertebrates to perform micro-ecosystem services to facilitate physiological functions. Despite the key role of the GMB in host health, wildlife managers have been slow to consider the ramifications of anthropogenic pressures to wildlife-GMB diversity. For example, although diet is one of the most influential determinants of a host’s GMB, many wildlife agencies allow baiting with human-provisioned foods to facilitate the harvest of wildlife such as American black bear (Ursus americanus). Additionally, much of our knowledge of wildlife-GMB relationships is based on …

Ecological Studies Of An Abyssal Nodule Province To Inform The Management Of Deep-Sea Mining, Kirsty Alexandra Mcquaid

School of Biological and Marine Sciences Theses

The abyssal environment remains one of the most poorly studied parts of the planet. While predominantly an environment dominated by soft sediments, some abyssal regions are known to harbour potato-sized, rock-like formations known as polymetallic nodules. These nodule provinces are now the subject of exploration by nations and their nominated contractors keen to develop a new deep-sea mining industry. This new industry has the potential for large-scale environmental impacts, but at present these impacts are difficult to predict, and therefore mitigate, as a result of the lack of ecological data and scientific understanding of these areas. The studies carried out …

Land Use Influences Along Elevation Gradient On Macroinvertebrate Communities, Brittany Sprout

Electronic Theses and Dissertations

Land use activities have caused disturbances that affect the quality of freshwater ecosystems worldwide. How the influences of land use along an environmental gradient and the associated environmental variables that may influence stream diversity and function is unclear. We address these issues by studying biodiversity, abundance, and functional diversity of macroinvertebrates across different land types along a gradient in Colorado, USA. We also address how diversity may change along an elevation gradient by analyzing previously published macroinvertebrate research. We found evidence that land use and disturbance are stronger explanations of changes in macroinvertebrate communities, rather than elevation. Functional trait patterns …

Causes Of Variable Jarrah (Eucalyptus Marginata) And Marri (Corymbia Calophylla) Seedling Density At Establishment Following Bauxite Mining In The Northern Jarrah Forest Of Western Australia, Tai White-Toney

Theses

Seedling densities at establishment of jarrah (Eucalyptus marginata D. Don ex Sm.) and marri (Corymbia calophylla (Lindl). K. D. Hill & L. A. S. Johnson) following bauxite mining in the Northern Jarrah Forest of south-western Australia are variable and few factors explored during 40 years of field studies have explained this variability. This study explored establishment within the framework of limitation due to amount of seed supply and number of suitable microsites for establishment. First, relationships were identified between seedling establishment densities on 654 mine sites restored between 1998 and 2017 and restoration practices (seed and fertiliser application rates), climate …

Composition Of Dung Beetle Communities In A Tropical Montane Forest Alters The Rate Of Dung Removal More Than Species Diversity Alone, Elizabeth A. Engle

Browse all Theses and Dissertations

Dung beetles provide key ecological functions by degrading and recycling dung. I used experimentally-assembled communities to examine the role of species richness, community biomass, species diversity, species identity, and community composition in dung removal, using Ateuchus chrysopyge, Copris nubilosis, Onothophagus cyanellus, and Dichotomius satanas. I hypothesized: (1) that as species richness, biomass, and diversity increases within a community, dung removal increases; and (2) species are not functionally equivalent, so community composition should influence dung removal rates. As species richness, biomass, and diversity of experimentally-assembled communities increased, the proportion of dung removed also increased. Also, the four species in this study …

Is Context Dependency Imperative To Understanding The Impacts Of Invasive Plants?, Brendan B. Haile

Masters Theses

Introduced exotic species have a tendency to become invasive and impact local biological communities. Invasions often impact community attributes such as cover and species richness, but these factors may also regulate patterns of invasion. In such cases, impacts may be dependent on the invasion context. We used data from the Buell-Small Succession Study, a long-term permanent plot study in the piedmont region of New Jersey, to document context dependency in invasion. To do this, we analyzed the factors that affected the colonization and growth of four invasive species, Alliaria petiolata, Lonicera japonica, Microstegium vimineum and Rosa multiflora, as well …

Ecology And Conservation Of Shrubland Bird Communities In The Eastern Ghats Of Indi, Anant Deshwal

Graduate Theses and Dissertations

Anthropogenic disturbance, in its multiple facets represents a major threat to biodiversity and habitat quality. Consequently, extensive research is guided towards understanding anthropogenic disturbance and their effects on wildlife for development of wildlife management plans. However, for development of effective wildlife management plans it is imperative that we understand the habitat use and preference by local fauna along with effects of anthropogenic presence. In this dissertation, I studied the habitat usage and preferences of Shrubland birds in the Eastern Ghats of India during the pre-monsoon and post monsoon seasons. Eastern Ghats show a marked difference from pre-monsoon season to post-monsoon …

Mammal Species Inventory Using Various Trapping Methods In Zone 4 Of Billy Barquedier National Park, Belize During Rainy Season, Mersady Redding

Animal Science Undergraduate Honors Theses

Belize is a small country, but it is extremely ecologically diverse. Based on the few studies conducted in Belize, the abundance of mammals is low but diversity is high. Particular findings note the number and identity of species differed between four sites in the Maya Mountains of Belize, indicating that a data set from a single site is not representative of the Neotropical region. Insufficient data is available to estimate current species richness of many areas in Belize, including Billy Barquedier National Park (BBNP). The objective of this study was to explore trapping and documentation methods of terrestrial mammals in …

Effects Of Water Table Depth And Edaphic Characteristics On Plant Diversity In A Southern Mississippi Pitcher Plant Bog, Patrick Kirby

Master's Theses

This study examined the effects that water table depth and soil characteristics have on plant species richness and species composition within pitcher plant bogs across seasons. Eight piezometers were installed at random distances to monitor long-term water table depth and pressure fluctuations along a ~710-meter line transect traversing upland and bog habitats. Vegetation sampling quadrats (n=128) were set up near each piezometer. Cover data and water table depths were collected in spring and late summer. Soil samples collected from each treatment group were used to obtain soil texture and nutrient data. The summer collection period yielded a total gdiversity of …

Dynamics And Ecological Implications Of The Ulva-Zostera Ecotone In Elkhorn Slough, California, María Vila Duplá

Master's Theses

Ecotones are transitional areas between adjacent ecological communities that have unique ecological qualities defined by space and time scales, and by the interactions between adjacent systems. Ecotones play an essential role in supporting biologically diverse communities, and are sensitive indicators of global change. An Ulva-Zostera ecotone extends along the northern shore of Seal Bend in Elkhorn Slough, an estuary located in central California. Although previous studies have mentioned the presence of the Ulva-Zostera ecotone, this was the first study to focus on understanding its driving factors, spatiotemporal dynamics, and overall ecological implications. A combination of habitat monitoring, water quality assessments, …