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Residency, Diel Movement, And Tidal Patterns Of Large Juvenile Bull Sharks (Carcharhinus Leucas) In Winyah Bay, Sc, Jeremy Lee Arnt

Electronic Theses and Dissertations

No abstract provided.

Responses Of Juvenile Atlantic Salmon To Competition And Environmental Change: Implications For Performance In Maine Streams, Nicole C. Ramberg-Pihl

Electronic Theses and Dissertations

New England’s climate is changing faster than that of any other region in the continental United States. Over the last century, Maine has experienced an increase in annual temperature of approximately 1.48^oC along with a 15 percent increase in annual precipitation. Temperature and precipitation play vital roles in shaping the ecology of freshwater environments. Therefore, changes in regional climate could undermine the structure and stability of Maine’s freshwater systems as they currently exist.

Maine currently harbors the last wild populations of Atlantic salmon (Salmo salar) in the United States. Atlantic salmon were once abundant in Maine …

Determining The Trophic Role Of Red Snapper (Lutjanus Campechanus) In Mississippi State Waters Using Stomach Content And Stable Isotope Analysis, Branden Kohler

Master's Theses

The goal of this study was to determine the diet composition, trophic position and ecological role of red snapper (Lutjanus campechanus) in Mississippi state waters utilizing stable isotopes (δ¹³C and δ¹⁵N) and stomach content analysis. Stable isotope analysis of fish and their prey can provide information on species-specific basal resource utilization, diet composition and trophic position which can improve food web models and inform fisheries management decisions. Particulate organic matter (POM), the presumed base of the food web, red snapper muscle tissue, and red snapper stomach contents were collected from 25 sites in 2016 and …

An Examination Of The Influence Of Multi-Scale Processes And Connectivity On The Population And Assemblage Dynamics Of Headwater Fishes, Josh P. Hubbell

Dissertations

Typified by their branching pattern, headwaters are numerically abundant as the density of these habitats increases with increasing distance from the base of a dendritic river system. Connectivity among headwaters is complex, resulting in the spatial isolation of populations. Headwater specialists have evolved a suite of traits that permit these species to permanently reside within these habitats. The spatial configuration and connectivity of headwaters has repercussions for metapopulations and meta-assemblages. I investigated how multi-scale processes and connectivity influenced the patch occupancy, coexistence, movement ecology, population structure, and gene flow of headwater specialists. In chapter two, I used occupancy modeling to …

Dietary Development And Nutritional Ontogeny In Gorilla Beringei : A Multi-Layered, -Omics Approach, Emma C. Cancelliere

Dissertations, Theses, and Capstone Projects

In species who consume folivorous diets, immature individuals must contend with the challenges of extracting nutrients from fibrous foods before dietary adaptations and strategies are fully developed. Additionally, immatures have distinct nutritional needs to support their stage-specific metabolic and biophysiological requirements. To meet these stage-specific needs, while constrained by underdeveloped feeding strategies and digestive capacities, immatures may adopt distinct diets better suited to their specific developmental context. However, where dietary modification is constrained by low dietary diversity or landscape homogeneity, it is unclear how immature individuals compensate through alternative strategies. In turn, little is known about the nutritional and life …

Carbon Sequestration In A Restored West Michigan Oak Savanna: Implications For Management Practices, Jeffrey A. Heise

Masters Theses

The savanna system is an ecosystem (i.e. a transitional ecosystem) that lies between forest and grassland ecosystems. They occur across the world in various forms, but in the North American Midwest they are specifically oak savannas: systems where the open overstory is dominated by various species of oak (Quercus spp.) and the understory consists of carbon-rich prairie grasses and forbs. This ecosystem is a highly degraded ecosystem and has lost almost 99% of its former range due to agriculture and fire suppression. Since savannas are fire-evolved systems, they are maintained by and require fire as a regular disturbance to …

Movements Of White-Headed And White-Backed Vultures, Teague K. Scott

Boise State University Theses and Dissertations

Vultures are the only obligate vertebrate scavengers, and as such provide crucial services as keystone species and support the health and function of ecosystems in which they live. African vultures are a diverse group, with nine species found throughout Sub-Saharan Africa, many with overlapping distributions. Unfortunately, African vultures are faced with numerous threats throughout their range that have led to significant population declines, some greater than 90%, in only three generations. Four of these species are currently listed as critically endangered, and three as endangered.

Despite the significant perils faced by African vultures, there are still significant knowledge gaps and, …

Congruence And Temporal Variation Of Floral Visitation And Pollen Transport Networks In Southern Appalachia, Daniel A. Barker

Electronic Theses and Dissertations

Observation of floral visitation is an accepted method to describe plant-pollinator interactions despite potential biases. Collecting pollen from pollinators offers new insights on the structure and function of plant-pollinator communities. Furthermore, the strength and frequency of plant-pollinator interactions can vary across temporal scales. However, within-season and within-day (morning vs. evening) variation in plant-pollinator networks has been little studied. By evaluating variation in network structure across these biologically relevant time scales, we will gain a better understanding of the factors that shape plant-pollinator communities. The objectives of this study are to 1) Compare the structure of plant-pollinator networks built on floral …

Impact Of Disturbance Regimes On Community And Landscape Biodiversity In Atlantic Coastal Pine Barren Ecoregion Streams, Sean T. Mccanty

Graduate Doctoral Dissertations

Streams are dynamic systems shaped by geographic location, hydrology, riparian vegetation, and in-stream habitat. Furthermore, ecosystem disturbance plays a major role in structuring stream communities and ecosystem processes. Disturbances include natural occurrences, such as flooding, drought, and fire events and anthropogenic disturbances such as land use changes, damming, and pollution. Agricultural use acts as a press disturbance regime, homogenizing the surrounding landscape and simplifying in-stream habitat, leaving legacy effects after farming ceases. Active restoration is intended to ameliorate these effects by reintroducing variation, with the goal of shifting the ecosystem into a more diverse and natural state. The act of …

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 …

Impact Analysis On The Invasive Oriental Weather Loach (Misgurnus Anguillicaudatus) In The Grant Creek And Prairie Creek Watersheds At Midewin National Tallgrass Prairie, Adam Vanhaitsma

Pence-Boyce STEM Student Scholarship

In 2014, the invasive Oriental weather loach was found in the Prairie Creek wetland at Midewin National Tallgrass Prairie. While little is known about the Oriental weather loach and its impact on freshwater ecosystems it has become a widespread invasive species. Being the first to investigate the impact of the Oriental weather loach on the Grant Creek and Prairie Creek watersheds at Midewin National Tallgrass Prairie, we set traps for specimens from early June till late July in both watersheds. Each loach that was caught was euthanized and dissected in order to understand what the Oriental weather loaches are eating …

Analyzing Thermal Gradients Using Terrestrial Laser Scanning In Scrub Oak Habitats, Alyssa Silbey

Honors Theses

Thermal microclimates are an important component of natural ecosystems because they provide appropriate niche space for many organisms; however, they are not widely studied because of their small scale. Likewise, variation in these microclimates may significantly impact animal thermoregulation and plant physiological processes and be especially important in the face of climate change. The goal of this study is to determine how the size and structure of Quercus ilicifolia shrubs influences ground temperature gradients. We hypothesized that differences in leaf cover and leaf area index (LAI) would cause temperature under shrubs to cool relative to the ambient temperature, and that …

Behavioral Ecology Of Territorial Aggression In Uca Pugilator And Uca Pugnax, Abbey N. Thomas

Honors Theses

The nature of animal aggression has long been a research interest in many different scientific fields. Resources, including food, shelter, and mates are all common assets for which animals compete. Two species of fiddler crabs, the Atlantic Sand Fiddler Crab (Uca pugilator) and the Atlantic Marsh Fiddler Crab (U. pugnax) were studied in regards to their aggression shown when competing for shelter. One crab was placed in a contained shelter for two days, and then a second of the same species was introduced. Aggressive interactions were scored and compared with claw and carapace size to ascertain …

Ecological Analyses Of Macroinvertebrates And Fish Species In Six Streams On A Louisiana Military Base From 2001 To 2019, Danielle Joerger

Biology Theses

An in-depth ecological analysis of how and why the aquatic community changes over time was conducted for 6 streams on the Fort Polk military base in Louisiana using data collected from 2001 to 2019. Fort Polk is a unique location as nineteen first-order streams are located on the premises belonging to three separate drainages. The primary goal was to determine whether temporal or between-drainage variation has a larger effect on community structure. To accomplish this the effects of disturbance on fish and macroinvertebrate assemblages was determined temporally and between drainages. Several hypotheses were drawn from this: 1) temporally, assemblages exhibit …

Historical And Contemporary Variables Affecting The Range And Distribution Of Aedes Aegypti, The Yellow Fever Mosquito, In The United States, Nicole Mackey

Master's Theses

Aedes aegypti, the primary mosquito vector of the yellow fever virus, threatens global health by passing on this virus, as well as chikungunya, dengue, and Zika viruses. Through its natural tendency to live in highly urban areas and bite human hosts; understanding the factors that affect the historical and current range of the pest is invaluable (Gubler, 1998). Although these viruses are not normally found in the United States, lack of vaccinations and wide-spread presence of the mosquito could lead to these diseases being reintroduced with potentially devastating effects (Monath, 2001). To determine a partial historical range of A. aegypti …

Chronoecology Of A Cave-Dwelling Orb-Weaver Spider, Meta Ovalis (Araneae: Tetragnathidae), Rebecca Steele

Electronic Theses and Dissertations

Circadian clocks enable coordination of essential biological and metabolic processes in relation to the 24-hour light cycle. However, there are many habitats that are not subject to this light cycle, such as the deep sea, arctic regions, and cave systems. This study analyzes the circadian pattern of isolated populations of a subterranean spider, Meta ovalis from two Tennessee caves and five Indiana caves. Locomotor activity was recorded with TriKinetics LAM50 Locomotor Activity Monitor under a 12-hour light (L), 12-hour dark (D) (LD 12:12) cycle preceding total darkness (DD). Significant differences were found within and among populations found in Tennessee cave …

Vegetative Community And Health Assessment Of A Constructed Juncus-Dominated Salt Marsh In The Northern Gulf Of Mexico, Nickolas R. Murphy

Master's Theses

Deer Island is a coastal habitat which provides a buffer from storm and flood damage as well as shore-line stabilization to the mainland of Biloxi, Mississippi. A third of the land has been lost since 1850, largely driven by tropical storm and hurricane impacts as well as sea level rise. The United States Army Corps of Engineers and Mississippi Department of Marine Resources have targeted the shores of the island as sites for restoration using beneficial use dredged material, and two sites of differing age have since been planted with Spartina alterniflora, Juncus roemerianus, Uniola paniculata, S. patens, and Panicum …

Temporal Factors Affecting Foraging Patterns Of A Diurnal Orb-Weaving Spider, Micrathena Gracilis (Araneae: Araneidae), Mitchell Davis Long

Undergraduate Honors Theses

Several studies have investigated the ecological factors that affect behavior in Micrathena gracilis, a diurnal orb-weaving spider that forages on flying insects during the day. However, none yet have considered how the temporal distributions of prey and predator occurrences shape their daily behavioral rhythms, especially web construction, which involves a heavy energetic investment well in advance of potential nutritional benefit. Recently, several orb-weaving spider species have been shown to exhibit a variety of abnormal rhythms, suggesting that circadian clock-controlled rhythms may play an unexpected role in behavioral evolution. Despite the appearance of significant insect abundance in the evenings, M. gracilis …

Examination Of Parasite Assemblages In Killifish Of The Genus Fundulus Across The Atlantic Coast Of The United States And Canada, Derek Garvey

HCNSO Student Theses and Dissertations

Killifish of the genus Fundulus were examined to assess the factors shaping parasite community structure at a genus level. A database of previous parasite surveys on Fundulus species across the Atlantic coast of the United States and Canada was created from a literature review. The database included parasite and environmental factor data from 15 sources. Additional sites from New Brunswick, Maine, Massachusetts, Rhode Island, North Carolina, and South Carolina were sampled for Fundulus species. The resulting database includes data for 10 species from a total of 57 unique geographic sites. Data on the diversity and abundance of metazoan parasites were …

Feeding Ecology Of Red Snapper (Lutjanus Campechanus) And Vermilion Snapper (Rhomboplites Aurorubens) Coexisting At The Louisiana Shelf-Edge Banks, Katherine M. Ellis

LSU Master's Theses

Niche partitioning, the process by which competing species use different subsets of the available resources, is commonly used to explain the coexistence of closely related species. In the northwest Gulf of Mexico on the shelf-edge banks, red snapper (Lutjanus campechanus) and vermilion snapper (Rhomboplites aurorubens) are two coexisting closely related species. Yet, little is known about how these species partition resources. In this study, niche partitioning of red snapper and vermilion snapper was investigated using gut contents and stable isotopes. While dietary niche partitioning was apparent, the species relied upon similar prey and displayed isotopic niche overlap, …

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 …

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 …

The Effects Of Low-Level Pharmaceuticals On Stream Biofilm Structure And Function Across A Land-Use Gradient In Streams Of The Huron River Watershed, Elizabeth Mae Stover

Master's Theses and Doctoral Dissertations

Pharmaceuticals and personal care products (PPCPs) are a contaminant class of worldwide concern. Their environmental omnipresence indicates they may be a potential source of global change, and ecosystem-scale impacts at non-lethal levels have not been fully explored. We used stream biofilms to assess ecosystem responses to PPCPs. Biofilms were cultivated in streams draining areas of different land use and then exposed to triclosan, diphenhydramine, and sulfamethoxazole-trimethoprim treatments. We found evidence that low levels of these PPCPs affected some, but not all, aspects of biofilm processes and bacterial community composition. Bacterial carbon uptake was reduced (p = 0.06) and we found …

Stressed Out: Life-History Strategy And The Costs Of Multiple Stressors In Gryllus Crickets, Sugjit S. Padda

University of the Pacific Theses and Dissertations

The frequency, duration, and co-occurrence of several environmental stressors are increasing globally. Multiple stressors may have compounding or interactive effects on animals, resulting in either additive or non-additive costs, but animals may mitigate these costs through various strategies of resource conservation or shifts in resource allocation. Thus, through two related factorial experiments, I measured a range of traits—from those related to life history and behavior to underlying physiology— to investigate the nature of costs (additive, non-additive, or neither additive nor non-additive), cost-mitigating strategies (resource conservation or allocation), and life-history strategy related to multiple stressors. First, I leveraged life-history strategy differences …

Diversity Analysis Of Soil Fungus Communities In Disturbed, Nursery, And Mature Forest Conditions, Dana Whitmore

All Master's Theses

Populations of soil fungi were examined in Derby Canyon Natives, Coeur d’Alene Forest Service nursery, Swamp Lake, and the Keechelus Lake wildlife overcrossing soils. All sampling sites were connected by their relation to the revegetation and native soil plug inoculation of the wildlife overpass. This study was an effort to describe soil fungi communities present on the overpass before plant introduction, those that plants would be bringing in their pots, and the fungi that could be introduced via soil plug transplantation. DNA was extracted from soil samples, then sequenced using next-generation sequencing methods, allowing for the analysis of species richness …

The Influence Of Landscape Factors On Black-Tailed Prairie Dog (Cynomys Ludovicianus) Colony Persistence In Northwest Kansas, Jamie Oriez

Master's Theses

The black-tailed prairie dog (Cynomys ludovicianus) is a colonial and fossorial rodent species that serves as an ecosystem engineer and keystone species in North America’s grasslands. Black-tailed prairie dogs historically ranged from northern Mexico to southern Canada, and from eastern Nebraska to the foothills of the Rocky Mountains. However, with the loss and fragmentation of grasslands, introduction of Sylvatic plague (Yersinia pestis), and control measures such as poisoning and shooting, black-tailed prairie dogs are limited to less than 5 percent of their historical range.

In this study, I examined how colony area, location, isolation, and surrounding …

Physiological Ecology Of Overwintering And Cold-Adapted Arthropods, Leslie Jean Potts

Theses and Dissertations--Entomology

Given their abundance and diversity, arthropods are an excellent system to investigate biological responses to winter. Winter conditions are being majorly impacted by climate change, and therefore understanding the overwintering biology of arthropods is critical for predicting ecological responses to climate change. In Chapters 2 and 3, I investigate the winter biology of a winter-active wolf spider. I show that winter-active spiders can take advantage of periodic prey resources and grown in the winter, which may allow them to get a jumpstart on spring reproduction. I also investigate spiders’ ability to track changes in their environment by quantifying low temperature …

Influence Of Light Availability On Tree Growth, Defense, And Emerald Ash Borer (Agrlius Planipennis) Success In White Fringetree (Chionanthus Virginicus) And Black Ash (Fraxinus Nigra), Michael S. Friedman

Browse all Theses and Dissertations

White fringetree is a host for the invasive emerald ash borer (EAB) despite being lower quality than black ash. Observations suggest that host trees grown in full sun are more resistant to EAB than those grown in shade, however chemical defense mechanisms and the impact of environmental stress have not been assessed. We quantified constitutive and induced defenses and other characteristics white fringetree and black ash phloem tissue grown under differential light conditions, and these traits were related to EAB larval performance. White fringetree had significantly lower constitutive and induced activities of defense associated enzymes and lignin but higher phenolic, …

Fate Of White Fringetree Through The Invasion Wave Of Emerald Ash Borer And Its Variation In Resistance To Attack, Emily A. Ellison

Browse all Theses and Dissertations

Ornamental white fringetrees in IL, IN, OH, and PA were reassessed in 2018 as a follow-up study to determine the fate of the white fringetree through the invasion wave of emerald ash borer. Attack rates decline by half from 2015-2018 and only 13% of trees were infested. Health of not reinfested trees in 2018 improved suggesting resilience against EAB attack whereas currently infested trees in 2018 displayed signs of declining health. Trees differed in their resistance to EAB attack and 41 additional ornamental and wild white fringetrees were studied in OH to determine if the anti-herbivory defense chemical, oleuropein, influenced …

Effects Of Forest Age And Composition On Coleoptera Associated With Fungal Fruiting Bodies In Southwest Ohio, Jeffrey M. Brown

Browse all Theses and Dissertations

Mature forests often harbor greater biodiversity than younger woods. As this relationship of forest age to biodiversity has not been examined for all taxa, this study sought to document the diversity of mycophilous beetle communities in deciduous forests of southwest Ohio and understand how they vary in relation to forest age. I surveyed fungus associated beetles using baited traps at eight forested sites in the Dayton, Ohio region. Traps were surveyed three times during 2018 to account for seasonal variation, something that has not been done for this geographic region. Forest age had no significant effect on beetle abundance or …