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Full-Text Articles in Ecology and Evolutionary Biology

Winter Roost Selection Of Eastern Red Bats And Impacts Of Non-Growing Season Prescribed Fire On Foraging Activity Of Forest Roosting Bats In Tennessee, Ashley D. Epstein May 2024

Winter Roost Selection Of Eastern Red Bats And Impacts Of Non-Growing Season Prescribed Fire On Foraging Activity Of Forest Roosting Bats In Tennessee, Ashley D. Epstein

Masters Theses

With an increase in wind energy development and continued deforestation and habitat degradation, eastern red bats (Lasiurus borealis; LABO) and other migratory foliage roosting bats (hoary bat [Lasiurus cinereus; LACI], silver-haired bat [Lasionycteris noctivagans; LANO]) are at risk of severe population declines, potentially leading to the need for protection under the Endangered Species Act. While studies have been done examining the ecology of these species, there is still a lack of research on winter roosting and foraging behaviors. This research aims to fill some of those knowledge gaps by 1) Examining roost use (i.e., trees vs. litter) …


Aquatic Transitions And Interspecific Relationships In Fissidens Mosses, Julia R. Butler May 2024

Aquatic Transitions And Interspecific Relationships In Fissidens Mosses, Julia R. Butler

Masters Theses

Embryophytes have undergone numerous re-invasions to aquatic habitats, impacting their morphological evolution. Despite the prominence of these transitions, their phylogenetic implications and morphological adaptations are just beginning to be investigated, especially as molecular methodologies become more accessible. We investigate these phenomena using the genus Fissidens, a diverse group of mosses encompassing both terrestrial and aquatic species. Our study integrates phylogenetic methods with morphological analyses to elucidate the evolutionary patterns within Fissidens and explore correlations between habitat transitions and morphological traits. Through extensive taxon sampling from herbarium specimens, DNA extraction, and sequencing, we construct robust phylogenetic trees using concatenated and …


Evaluating Current And Future Potential Distribution Of Epiphytic Orchids In The Congo Basin With Ecological Niche Models, Michael L. Ngoh Aug 2022

Evaluating Current And Future Potential Distribution Of Epiphytic Orchids In The Congo Basin With Ecological Niche Models, Michael L. Ngoh

Masters Theses

The Congo Basin Forest harbors a rich diversity of epiphytic communities, with the Orchidaceae alone making up more than 50% of all epiphytes in the region. Despite the huge diversity of epiphytes, many species, including epiphytic orchids, are at risk to a diverse array of threats. Climate change for instance poses severe threats to epiphytic orchids due to elevated temperatures, prolonged periods of droughts, as well as reduced rainfall across the Congo Basin Forest. In this study, we used ecological niche modeling and GIS techniques to identify spatial patterns of species richness, potential future climate refugia, and novel climatic suitability …


Climate-Driven Selection Results In Powerful Geographic Framework For Predicting Phenotype, Alexandra Neild May 2022

Climate-Driven Selection Results In Powerful Geographic Framework For Predicting Phenotype, Alexandra Neild

Masters Theses

Our ability to prepare for and mitigate the likely ecological and evolutionary impacts of climate change largely depends upon our ability to predict the phenotypic responses of organisms that allow them to persist, adapt, and migrate along environmental stress gradients. Using fifteen populations of cottonwoods, a dominant riparian forest tree, that are distributed along elevation gradients and represent three genetic provenances, we hypothesized and show that: 1) populations within a provenance demonstrate parallel evolutionary responses to climatic gradients associated with elevation; and 2) the evolutionary effects of elevation on bud-break phenology varied by provenance. Across all populations, we find strong …


Life History, Diet And Habitat Of The Federally Endangered Laurel Dace (Chrosomus Saylori), Shawna M. Fix May 2021

Life History, Diet And Habitat Of The Federally Endangered Laurel Dace (Chrosomus Saylori), Shawna M. Fix

Masters Theses

Laurel Dace (Chrosomus saylori) is a small, freshwater minnow that is endemic to headwater streams on Walden Ridge, Tennessee. The species was listed as federally endangered in 2011 and the U.S. Fish and Wildlife Service Recovery Plan indicates a need for life history, diet and habitat studies. A literature review, samples of archived specimens, and a surrogate species, the Tennessee Dace (Chrosomus tennesseensis), were used to describe the life history and diet of the Laurel Dace. A total of 370 Tennessee Dace were collected from Laurel Ford Branch, a stream 8.6 km from the Laurel Dace …


Conservation Of Terrestrial Salamanders Through Hemlock Woolly Adelgid Management In Eastern Hemlock Forests Within Great Smoky Mountains National Park, Jonathan Lawrence Cox Dec 2020

Conservation Of Terrestrial Salamanders Through Hemlock Woolly Adelgid Management In Eastern Hemlock Forests Within Great Smoky Mountains National Park, Jonathan Lawrence Cox

Masters Theses

Hemlock woolly adelgid (Adelges tsugae; HWA), an invasive aphid-like arthropod, was first documented on the east coast of the United States in the 1950s. HWA is an herbivore which primarily feeds at the needle base of hemlock tree species (Pinaceae: Tsuga). With no evolutionary defenses and few biotic controls, the eastern and Carolina hemlock (Tsuga canadensis and Tsuga carolinensis) serve as the primary diet of HWA in eastern North America. The invasive pest began to spread rapidly throughout the hemlock’s range causing defoliation and death of the trees within 4 – 10 years. With the …


Carbon Metabolism In Cave Subaerial Biofilms, Victoria E. Frazier Dec 2020

Carbon Metabolism In Cave Subaerial Biofilms, Victoria E. Frazier

Masters Theses

Subaerial biofilms (SABs) grow at the interface between the atmosphere and rock surfaces in terrestrial and subterranean environments around the world. Multi-colored SABs colonizing relatively dry and nutrient-limited cave surfaces are known to contain microbes putatively involved in chemolithoautotrophic processes using inorganic carbon like carbon dioxide (CO2) or methane (CH4). However, the importance of CO2 and CH4 to SAB biomass production has not been quantified, the environmental conditions influencing biomass production and diversity have not been thoroughly evaluated, and stable carbon and nitrogen isotope compositions have yet to be determined from epigenic cave SABs. …


Environmental Controls On The Diversity And Distribution Of Endosymbionts Associated With Phacoides Pectinatus (Bivalvia: Lucinidae) From Shallow Mangrove And Seagrass Sediments, St. Lucie County, Florida, Thomas Walters Doty Dec 2015

Environmental Controls On The Diversity And Distribution Of Endosymbionts Associated With Phacoides Pectinatus (Bivalvia: Lucinidae) From Shallow Mangrove And Seagrass Sediments, St. Lucie County, Florida, Thomas Walters Doty

Masters Theses

Lucinid bivalves are capable of colonizing traditionally inhospitable shallow marine sediments due to metabolic functions of bacterial endosymbionts located within their gills. Because lucinids can often be the dominant sediment infauna, defining their roles in sediment and pore fluid geochemical cycling is necessary to address concerns related to changes in coastal biological diversity and to understanding the sensitivity of threatened coastal ecosystems over time. However, there has been limited research done to understand the diversity and distribution of many lucinid chemosymbiotic systems. Therefore, the goals of this thesis were to evaluate the distribution of Phacoides pectinatus and its endosymbiont communities …


Effects Of Forest Management Practices On Raccoon Ecology In A Longleaf Pine Ecosystem, Ronald Brian Kirby Dec 2015

Effects Of Forest Management Practices On Raccoon Ecology In A Longleaf Pine Ecosystem, Ronald Brian Kirby

Masters Theses

Raccoons (Procyon lotor) are ecological generalists common throughout a variety of habitats across their range. Although considered an economically important furbearer species in many regions, they are considered potentially important nest predators of certain species. Because raccoons may have a significant ecological impact on the landscape, it remains important to understand their ecology in a variety of ecosystems. We studied raccoon ecology in a longleaf pine ecosystem in southwestern Georgia, where little information for the species exists. Specifically, we assessed 269 daytime resting sites (i.e., refugia) associated with 31 radio-collared adult raccoons (18M, 13F) during 2014-2015 using an …


Survival And Growth Rate Of Translocated Freshwater Mussels Lampsilis Fasciola And Medionidus Conradicus, Laura L. Pullum Aug 2015

Survival And Growth Rate Of Translocated Freshwater Mussels Lampsilis Fasciola And Medionidus Conradicus, Laura L. Pullum

Masters Theses

Freshwater mussels (Family Unionidae and Margaritiferidae) are a widely threatened group of bivalve molluscs, particularly in the Southeastern United States. Translocation of freshwater mussels is an increasingly common conservation method. However, there are relatively few studies that quantitatively investigate the factors influencing translocation success or failure. In October 2013, hundreds of Medionidus conradicus and Lampsilis fasciola were translocated to the Pigeon and Nolichucky Rivers in Tennessee, with an interim partial survey (June 2014) and a full survey (October 2014). In this study, I analyze this field-collected data to determine the mechanism(s) that currently influence the outcomes of Tennessee mussel translocation. …


Influence Of Habitat Manipulations On Northern Bobwhite Resource Selection On A Reclaimed Surface Mine, Jarred Milford Brooke May 2015

Influence Of Habitat Manipulations On Northern Bobwhite Resource Selection On A Reclaimed Surface Mine, Jarred Milford Brooke

Masters Theses

Northern bobwhite populations have declined range-wide over the past 40 years. The intensification of agriculture, conversion of pastures to nonnative cool-season grasses, advanced succession, and urbanization have resulted in the deterioration and elimination of bobwhite habitat. Recent conservation efforts have called for a landscape-level approach to the conservation of northern bobwhite populations. However, identifying large areas to manage bobwhite populations is problematic. Reclaimed mine lands offer an opportunity to manage large contiguous tracts of early successional vegetation to conserve northern bobwhite populations. We studied northern bobwhite resource selection throughout the year from August 2009 to March 2014. We investigated the …


Habitat Use And Response To Wetland Management Practices Of Non-Breeding Dabbling Ducks In Western Tennessee, Matthew Doddridge Mcclanahan May 2015

Habitat Use And Response To Wetland Management Practices Of Non-Breeding Dabbling Ducks In Western Tennessee, Matthew Doddridge Mcclanahan

Masters Theses

Western Tennessee is an important area for non-breeding waterfowl in the Mississippi Flyway, including over 40% of the Mississippi Flyway population of American black ducks (Anas rubripes, hereafter black ducks), a species in decline. Information is lacking on waterfowl community ecology in the region, and managers must identify key habitats and consider functional use and potential predictors of resource use by non-breeding communities. Impacts of wetland management practices, such as moist-soil disking and subsequent planting of desirable grasses (i.e., Japanese millet [Echinochloa frumentacea], hereafter millet), must also be tested relative to impacts on waterfowl use and …


Freshwater Mussels (Bivalvia: Margaritiferidae And Unionidae) Of The Buffalo River Drainage, Tennessee, Matthew Philip Reed May 2014

Freshwater Mussels (Bivalvia: Margaritiferidae And Unionidae) Of The Buffalo River Drainage, Tennessee, Matthew Philip Reed

Masters Theses

The Buffalo River in Tennessee once hosted a rich population of freshwater mussels. During the 1980s, monitoring efforts demonstrated evidence of drastic declines and extirpation of entire assemblages. Increases in municipal development in the headwater tributaries and agriculture in the main stem of the Buffalo River are suspected causes for mussel community declines throughout the river. In 2011, collection data documented evidence of recovery in the lower Buffalo River. The aims of this project were: 1) to update the status, distribution, and species composition of mussels in the Buffalo River and its major tributaries through qualitative sampling, and 2) to …


Habitat Selection And Partitioning Among Darters In Two Tributaries Of The Clinch River, And Stream Restoration Effects On Substrate Profile, Daniel James Walker May 2014

Habitat Selection And Partitioning Among Darters In Two Tributaries Of The Clinch River, And Stream Restoration Effects On Substrate Profile, Daniel James Walker

Masters Theses

The group of fish referred to as darters is extremely biodiverse. Often, several closely related species will inhabit the same areas of streams, and prior research has investigated how these species may be partitioning the resources in low-order streams in which they are sympatric. The habitat partitioning of darters in two streams in the Clinch River system, Coal and Cove Creeks, was investigated. The study sites were picked due to their involvement in both physical and biological stream restoration efforts within the last several years, including the collection, translocation, and reintroduction of rainbow darters (Etheostoma caeruleum) from reference sites in …


Population Demographics And Genetic Structure Of Black Bears In Coastal Louisiana, Jesse Charles Troxler Dec 2013

Population Demographics And Genetic Structure Of Black Bears In Coastal Louisiana, Jesse Charles Troxler

Masters Theses

The range and abundance of the Louisiana black bear (Ursus americanus luteolus) were greatly diminished during the 20th century. This subspecies was reduced to 3 small, isolated subpopulations in Louisiana as bottomland hardwood habitat was converted to agriculture. These bears were listed as threatened by the U.S. Fish and Wildlife Service in 1992 and a recovery plan was published in 1995. Recovery requires estimates of population parameters to evaluate current population status and future viability. I conducted a mark-recapture study from 2010 to 2012 to estimate demographic parameters of the coastal population of Louisiana black bears. Because inbreeding …


Prevalence And Transmission Potential Of Borrelia Burgdorferi In Three Species Of Wildcaught Plestiodon Spp. Skinks Of The Southeastern United States, Teresa Dianne Moody Aug 2013

Prevalence And Transmission Potential Of Borrelia Burgdorferi In Three Species Of Wildcaught Plestiodon Spp. Skinks Of The Southeastern United States, Teresa Dianne Moody

Masters Theses

In the southeastern United States, blue-tailed skinks (Plestiodon spp.) are important hosts for Ixodes scapularis ticks, the principal vector of Lyme disease (LD) in this region. Skinks and other southeastern lizards are not thought to be reservoir competent for Borrelia burgdorferi sensu stricto (Bbss), the etiological agent of LD in the United States. . Lizard-feeding by southeastern I. scapularis may tend to suppress sylvatic cycles of B. burgdorferi, and thus may be an important reason why LD case rates in the Southeast are much lower than in the Northeast and upper Midwest. Nevertheless, some skinks …


Soil Microbial Community Succession During Cadaver Decomposition, Kelly Lynn Cobaugh May 2013

Soil Microbial Community Succession During Cadaver Decomposition, Kelly Lynn Cobaugh

Masters Theses

Microbes play critical roles in nutrient cycling in terrestrial ecosystems. In particular, microbial decomposition of organic matter is a key step in carbon and nutrient cycling, linking above-ground and below-ground pools. It is well known that the microbial community changes in structure and function following the introduction of organic matter into a terrestrial system. The decomposition of plant litter has been extensively investigated but the decomposition of animal-derived organic matter has often been overlooked. The unique characteristics of animal input are hypothesized to dictate a distinct decomposition process. This study examined the microbial community responsible for decomposition of animal-derived organic …


Vegetation Response To Oak Savanna And Woodland Restoration In The Mid-South Usa, Andrew Lee Vander Yacht May 2013

Vegetation Response To Oak Savanna And Woodland Restoration In The Mid-South Usa, Andrew Lee Vander Yacht

Masters Theses

The decline and degradation of oak savanna and woodland communities throughout the Mid-South underscores the need to develop management techniques capable of their efficient and successful restoration. Therefore, my objectives for this work were to document plant community response to variations in canopy disturbance level, fire seasonality, and herbicide control of hardwood midstories. In Chapter One, I provide a thorough review of the current body of knowledge concerning open-oak communities and their restoration, with specific focus on herbaceous and woody plant response to canopy disturbance, fire, and herbicide midstory management. Chapter Two details the response of herbaceous and woody vegetation …


The Impacts Of Surface Mining Restoration Efforts On Soil Dwelling Nematode Communities In The Appalachian Region, Haley Shae Smith Dec 2012

The Impacts Of Surface Mining Restoration Efforts On Soil Dwelling Nematode Communities In The Appalachian Region, Haley Shae Smith

Masters Theses

Traditional restoration of post mining sites in the southeastern U.S. utilizes methods that discourage above and below-ground succession of native floral and faunal communities. Recent advances in mining restoration techniques proposed by the Appalachian Regional Reforestation Initiative (ARRI) have improved above-ground plant succession and growth rates in reclaimed sites by developing the Forestry Reclamation Approach (FRA), a process that discourages substrate compaction and encourages native plant succession. The below-ground component of these reclaimed areas remains undescribed, however. Below-ground invertebrate communities in mining restoration sites have been largely ignored, despite their potential importance to the long-term recovery of these profoundly disturbed …


The Effects Of Nutrient Limitation And Cyanophage On Heterotrophic Microbial Diversity, Claire Elyse Campbell May 2012

The Effects Of Nutrient Limitation And Cyanophage On Heterotrophic Microbial Diversity, Claire Elyse Campbell

Masters Theses

Marine viruses are critically important in the regulation of biogeochemical cycles and host microbial communities. In this study, we tested whether the indirect effects of virus predation on a phototroph (i.e., Synechococcus) affected the composition of co-occurring heterotrophic bacteria under nitrogen and phosphorus limitation in long-term chemostat experiments. Using 454 Titanium barcoded pyrosequencing of the 16S rRNA gene, microbial diversity and technical (i.e., sequencing) reproducibility were assessed for nine individual chemostats across five different time points. A total of 325,142 reads were obtained; 194,778 high-quality, non-cyanobacterial sequences were assigned to 110 OTUs. Our results show high reproducibility …


Soil Nitrogen Amendments And Insect Herbivory Alter Above-And Belowground Plant Biomass In An Old-Field Ecosystem, Jarrod Dwayne Blue Aug 2010

Soil Nitrogen Amendments And Insect Herbivory Alter Above-And Belowground Plant Biomass In An Old-Field Ecosystem, Jarrod Dwayne Blue

Masters Theses

Nutrient availability and herbivory can regulate primary production in ecosystems, but little is known about how, or whether, they may interact with one another. Here I investigate how nitrogen availability and insect herbivory interact to alter above- and belowground plant community biomass in an old-field ecosystem. In 2004, 36 experimental plots were established in which soil nitrogen (N) availability (at three levels) was manipulated and insect abundance (at two levels) in a completely randomized plot design. In 2009, after six years of treatment, I measured aboveground biomass and assessed root production at peak growth. Overall, I found a significant effect …


Plant Genotype And Environment Interact To Influence Soil Carbon And Nitrogen Dynamics, Clara Christina Pregitzer May 2010

Plant Genotype And Environment Interact To Influence Soil Carbon And Nitrogen Dynamics, Clara Christina Pregitzer

Masters Theses

Abiotic and biotic variation has been shown to be important in regulating nutrient cycling and belowground communities in natural systems. However, genetic variation in dominant plants as a driver of rates of nutrient cycling is still poorly understood and few studies have looked at genotype interactions across multiple environments. Using Populus angustifolia and a common garden approach, we hypothesized that all three factors: tree genetic variation, environmental conditions and genetic by environment (G x E) interactions would affect soil carbon (C) storage and nitrogen (N) cycling. Replicated copies of five different reciprocally planted Populus genotypes were studied in three separate …