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Gauging The Importance Of Microhabitat In Qualitative Macroinvertebrate Sampling In An Effluent Dominated Stream, Samuel James Gradle

Masters Theses

In the past different sampling strategies have been used to relate macroinvertebrate assemblages with habitat quality in the Sangamon River, above and below the sanitary district effluent discharge in Decatur, IL. The standard 20 jab method of proportional sampling in multiple microhabitats, based on QHEI physical habitat score, sampled allowed for comparison between sites based on overall community composition. However, it oversampled fine sediments, which dominate the Sangamon, therefore potentially missing sensitive taxa in isolated quality habitats. In the fall of 2016 I tested an enhanced qualitative approach to better gauge the importance of microhabitat types to macroinvertebrate assemblages in …

The Effect Of Artificial Light Pollution On Orientation Of Hatchling Loggerhead Sea Turtles (Caretta Caretta) In The Grand Strand Region, South Carolina, Emily S. Asp

Electronic Theses and Dissertations

Sea turtle hatchlings primarily utilize sight to detect differences in elevation and light intensity present along the horizon to navigate from the nest to the water’s edge. The addition of artificial lights can cause visual misdirection, resulting in disorientation (aimlessly wandering in circular paths) or misorientation (moving in distinct paths away from ocean). Extensive research has been done on effects of high levels of artificial light but little on effects of comparatively lower levels of artificial light on hatchling sea turtle orientation. This study examined these lower intensity areas to identify if there is a threshold of artificial light above …

Population Genetics And Distribution Of The Oriental Weatherfish, Misgurnus Anguillicaudatus, In Chicago Area Waterways, John Belcik

Master's Theses

Oriental Weatherfish (Misgurnus anguillicaudatus), native to Southeast Asia, are freshwater fish belonging to the family Cobitidae (loaches). They are benthic fish with the ability to breathe atmospheric air, and exhibit an unusual behavior of swimming vertically in the water column in response to changes in barometric pressure. Oriental Weatherfish appear to be successful invaders to North American waterways. Within the last century they have been sighted in freshwater systems throughout the United States, yet the distribution and source of this invasion are largely unknown. This study investigates the distribution patterns, surveying methods, and population genetics of the Oriental Weatherfish within …

The Soundscape Of The St. Johns River And Its Potential Impacts On The Habitat Use Patterns Of Bottlenose Dolphins, Carissa Deeann King

UNF Graduate Theses and Dissertations

The development of effective management plans for animal populations relies on an understanding of how the population is utilizing the habitat as well as the identification of any critical habitat areas. The St. Johns River (SJR), an urban estuary with a high level of anthropogenic disturbance, is home to a resident population of bottlenose dolphins (Tursiops truncatus). In chapter one, SJR dolphin habitat use patterns, the factors that influenced these patterns, and the critical habitat areas were identified. Significant associations were found in most pair-wise comparisons between season, behavioral state, group size, water depth, and location, indicating that …

Alá Es Primero: Faith And Culture On The Mexican-American Border, Alan Ventura

Open Access Theses & Dissertations

The purpose of this Thesis is to show how El Paso Latino Muslims create a new cultural language when they harmonize their Mexican cultural practices with Islam.

Grasshopper (Orthoptera: Caelifera) And Plant Community Relationships On Indio Mountains Research Station, Hudspeth County, Texas, Sara Ebrahim Baqla

Open Access Theses & Dissertations

An ecogeographic analysis of a grasshopper survey was conducted at eight sites on Indio Mountains Research Station (IMRS) in the Chihuahuan Desert during September 2014 through December 2015. Five sites contained ephemeral water sources (earthen tanks), one had perennial water (spring system), and two were open desert. A total of 23 grasshopper species were identified, and six of those were new records for the property. The most species rich site was Echo Tank, with 14 grasshopper species. A UPGMA dendrogram showed Red Tank and Rattlesnake Tank, both wetland sites, to be the most similar (CBR = .84). A poisson model …

Nutrient Removal And Vegetation Recovery Through Successive Harvesting Of The Invasive Hybrid Cattail (Typha X Glauca) In Great Lakes Coastal Wetlands, Kelsey Berke

Master's Theses

Excess nutrient levels have led to invasive hybrid cattail (Typha × glauca) dominance in many Laurentian Great Lakes coastal wetlands. Its ability to alter wetland structure and function has made T. × glauca a target invasive species with respect to Great Lakes coastal wetland

restoration. This study investigated the effect of harvesting invasive T. × glauca biomass on nutrient removal, specifically nitrogen and phosphorus, and plant diversity recovery in Great Lakes coastal wetland ecosystems. This study demonstrated that without considering external nutrient inputs and outputs, a single harvest at Cheboygan Marsh, MI could remove ~2% of the total N and …

Do Belugas (Delphinapterus Leucas), Bottlenose Dolphins (Tursiops Truncatus), & Pacific White-Sided Dolphins (Lagenorhynchus Obliquidens) Display Lateralized Eye Preference When Presented With Familiar Or Novel Objects?, Deirdre Yeater, Sara Guarino, Steve Lacy, Tricia Dees, Healther Hill

Psychology Faculty Publications

Lateralization of behaviors and information processing are common across species. Hypothesized to be crucial for more efficient responding to environmental stimuli, lateralization has been investigated for a number of topics. Cetaceans are proposed to be hemispheric specialists, given a small corpus callosum, complete decussation of the optic nerve, and the ability to respond to a different visual stimulus presented to each eye simultaneously. Research with cetaceans has shown strong biases in a number of behaviors, including swimming, foraging, social interactions, and responses to myriad visual stimuli. Given similar evolutionary pressures, different species of cetaceans should display similar lateralized preferences. Previous …

Evolution Of Antagonistic Relationships In Proteins: A Case Study Of Radialis- And Diviricata-Like Genes, Ao Gao

Theses and Dissertations

The antagonistic relationship of proteins describes the opponent interactions that result in one protein suppressing the function of another. Developmental genetic studies of Antirrhinum majus demonstrated that two transcription factors from the MYB gene family, RAD and DIV, interact through antagonism to regulate floral dorsoventral asymmetry. Interestingly, similar antagonistic interactions were found among proteins of FSM1 (RAD-like), MYBI (DIV-like), and DRIF in Solanum lycopersicum, which is involved in fruit development. Here, we report on the homology of these antagonistic MYB proteins based on reconstruction of the phylogeny of I-box-like and R-R-type clades, where RAD- and DIV-like belong, …

The Status Of Snapping Turtles (Chelydra Serpentina) In Virginia: Population Viability, Demography, Regulatory Analysis, And Conservation, Benjamin C. Colteaux

Theses and Dissertations

Snapping turtles (Chelydra serpentina) are being harvested in unprecedented numbers in the United States (US) to meet the needs of international markets. Over three million live snapping turtles from farm and wild caught stock were exported from the US to Asia in 2012-14 alone. In the Commonwealth of Virginia, records indicate that 29,860 snapping turtles were commercially harvested between 2000 and 2015. Size limits are often used to regulate harvest pressure in snapping turtles and other game species. I analyzed the historic harvest of eleven US states to test the efficacy of minimum-size limit regulations at reducing commercial …

The Effect Of Chronic Nutrient Addition From Wastewater On Forest Ecosystems At The Rice Rivers Center, Michael Beck

Theses and Dissertations

Wastewater application to land can be a useful tool for mitigating impacts of nutrient enrichment on aquatic systems. A land application treatment system at VCU’s Rice Rivers Center in Charles City County, VA provided an opportunity to study the impact of wastewater addition on the biogeochemistry of forests representative of the Mid-Atlantic Coastal Plain. Nutrient concentrations in throughfall and leachate were measured at Treatment and Control sites to assess differences in nutrient deposition and retention. Wastewater amended plots from the Walter L. Rice education building received 20-fold (N) and 6-fold (P) higher inputs relative to Control plots and plots located …

The Effects Of Disturbance And Species Specific Interactions On Diversity In An Agent Based Forest Simulation, Matthew E. Mills

Theses and Dissertations

In ecology literature, there is much data which suggests that conspecific negative density dependence (CNDD) and abiotic disturbances increase biodiversity in forests. This thesis elucidates the notion that not only do these two forces increase diversity, but they may also interact with one another in order to achieve higher levels of biodiversity. Abiotic disturbances, like fires and hurricanes, can indirectly impact conspecific effects because when these forces remove individuals from the landscape, the role of the conspecific effects will change. The interaction of these two factors in biodiversity are explored in an agent based forest simulation through a resource surface. …

Niche Conservatism Or Divergence: Insights Into The Evolutionary Histories Of Pinus Taeda, Pinus Rigida, And Pinus Pungens, Constance E. Bolte

Theses and Dissertations

Environmentally related selective pressures and community interactions are well-documented drivers for niche differentiation, as natural selection acts on adaptive traits best fit for survival. Here, we investigated niche evolution between and within Pinus taeda, Pinus rigida, and Pinus pungens and sought to identify which climate variables contributed to species divergence. We also sought to describe niche differentiation across genetic groupings previously identified for P. taeda and P. rigida. Ecological niche models were produced using Maximum Entropy followed by statistical testing based on a measure of niche overlap, Schoener’s D. Both niche conservatism and niche divergence were …

A Range-Wide Assessment Of Migratory Connectivity For The Prothonotary Warbler Using Stable Hydrogen Isotopes, Jessica Reese

Theses and Dissertations

Populations of many species of migratory birds are declining, and an understanding of how populations are linked between the breeding and nonbreeding grounds is necessary in order to determine drivers of declines. While all current tracking technologies to study the movements of small songbirds are limited by their coarse resolution, tracking birds by measuring stable isotopes in keratin offers an advantage because it requires only a single capture and is cost-effective, which leads to robust sample sizes. While this tracking method is accurate, stable hydrogen isotope values measured in feathers (δ²H_f) are known to be variable …

Habitat Use And Movement Patterns Of Two Redwood Forest Salamanders, Aneides Vagrans And Ensatina Eschscholtzii, With An Examination Of The Efficacy Of Pit Tags For Marking Small Plethodontids, Christian Brown

Cal Poly Humboldt theses and projects

The habitat use and movements of small, secretive salamanders are generally poorly understood, in part due to the difficulty associated with marking and recapturing such animals. This study was designed to test the efficacy, both in the laboratory and in the field, of using passive integrated transponder (PIT) tags to mark and track two small-bodied plethodontid salamander species native to coastal northwestern California, Aneides vagrans, the Wandering Salamander, and Ensatina eschscholtzii, the Ensatina Salamander.

Aneides vagrans inhabits tree crowns. Using cover objects and visual encounter surveys, I searched for A. vagrans in the angiosperm understory canopy at least twice …

Movement, Habitat, And Home Range Of Introduced Bullfrogs (Lithobates Catesbeianus) On Mad River Gravel Ponds (Humboldt Co., Ca, Usa), With Implications For Hydro-Modification As A Method Of Management, Madeline C. Cooper

Cal Poly Humboldt theses and projects

American Bullfrogs are a non-native, invasive species in California (USA), where they are known to have deleterious effects on many native species. Carnivorous adults prey on native amphibians and fish, while herbivorous tadpoles outcompete native tadpoles for algal food resources. Bullfrogs have been successful at colonizing old tailing ponds and other pools left over from mining activities, and these relict pools are common on many rivers in California. Information on the dispersal capabilities of Bullfrogs could help predict range expansions and inform management decisions. Unfortunately, this information is lacking from both their native and invaded range. From May to August …

Modeling The Spread Of Sudden Oak Death Across A Heterogeneous Landscape In Redwood National Park Using A Spatially-Explicit Epidemiological Model, Laura A. Morgan

Cal Poly Humboldt theses and projects

The pathogen Phytophthora ramorum, the causal agent of Sudden Oak Death (SOD), is responsible for the deaths of millions of oak (Quercus spp.) and tanoak (Notholithocarpus densiflorus) trees in California and Oregon (USA). A recent infection in Redwood National Park (RNP) in California (USA) provided an opportunity to adapt an existing SOD model to assess the efficacy of current and proposed management strategies. A common method of SOD treatment includes killing both infected and uninfected hosts in the area of infection, as well as the area surrounding the infection to create buffers to account for undetected …

Darlingtonia Californica Phytotelma Organisms: Spatial Relations Within The Metacommunity, Stefani Marie Brandt

Cal Poly Humboldt theses and projects

The California pitcher plant, Darlingtonia californica, provides a unique setting to research community ecology because it harbors small ponds of water, or phytotelmata, in its modified leaves. Each phytotelma hosts a unique community of various invertebrates who live among carcasses of drowned plant prey. These pitchers and their inquiline communities are relatively small yet abundant in the wild, resulting in an ideal natural setup for community composition comparisons. There have been no previous studies that research D. californica inquiline communities across multiple geographic regions concurrently. This study sought to survey phytotelma communities throughout the range of D. californica at …

An Estimation Of Potential Salmonid Habitat Capacity In The Upper Mainstem Eel River, California, Emily J. Cooper

Cal Poly Humboldt theses and projects

In Northern California’s Eel River watershed, the two dams that make up the Potter Valley Project (PVP) restrict the distribution and production of anadromous salmonids, and current populations of Chinook Salmon (Oncorhynchus tshawytscha) and steelhead trout (O. mykiss) in the upper mainstem Eel River are in need of recovery. In anticipation of the upcoming FERC relicensing of the PVP, this project provides an estimation of the extent of potential salmonid habitat and its capacity for steelhead trout and Chinook Salmon in the upper mainstem Eel River watershed above the impassable Scott Dam. Using three fish passage …

Eukaryotic Microbes, Principally Fungi And Labyrinthulomycetes, Dominate Biomass On Bathypelagic Marine Snow, Alexander B. Bochdansky, Melissa A. Clouse, Gerhard J. Herndl

OES Faculty Publications

In the bathypelagic realm of the ocean, the role of marine snow as a carbon and energy source for the deep-sea biota and as a potential hotspot of microbial diversity and activity has not received adequate attention. Here, we collected bathypelagic marine snow by gentle gravity filtration of sea water onto μm filters from similar to 1000 to 3900 m to investigate the relative distribution of eukaryotic microbes. Compared with sediment traps that select for fast-sinking particles, this method collects particles unbiased by settling velocity. While prokaryotes numerically exceeded eukaryotes on marine snow, eukaryotic microbes belonging to two very distant …

Factors Affecting Growth Rates And Preferred Body Temperatures In Hatchling Gopher Tortoises, Gopherus Polyphemus: Clutch And Sex, Matthew Carey

College of Graduate Studies: Theses & Dissertations

Post hatching growth rates in tortoises can affect size at sexual maturity This study looks at what affect clutch and sex has on hatchling tortoises from these two sites as this data is lacking/insufficient from two populations in Southeast Georgia. Eggs were allowed to incubate in natural nests and then were collected between August 19-21, 2015 and hatched in an incubator in the lab. When they hatched, the tortoises were kept in a single room with a rearing temperature that averaged 26.9° C. Sex was determined using laparoscopy at the end of the study to ensure gonad development and to …

Quantifying Relationships Between Phosphorus Availability And Mycorrhizal Associations In Wetland Plants, Daniel Marshall

Theses and Dissertations (Comprehensive)

Increasing evidence indicates that plant community structure and therefore ecosystem function are mediated by below-ground fungal communities that form intracellular associations with plant roots called mycorrhizal associations. Arbuscular mycorrhizal fungi (AMF) are a type of mycorrhiza that colonize the plant host intracellularly but maintain hyphae outside the root cell for resource acquisition. The importance and function of AMF associations are well-documented in terrestrial ecosystems, but are less understood in aquatic or semi-aquatic systems. Phosphorus availability is the primary factor influencing mycorrhizal colonization and growth in terrestrial soils, with phosphorus-abundant soils leading to a decrease in mycorrhizal growth. However, the relationship …

Crassulacean Acid Metabolism As A Continuous Trait: Variability In The Contribution Of Crassulacean Acid Metabolism (Cam) In Populations Of Portulacaria Afra, Lonnie J. Guralnick, Kate Gladsky

Arts & Sciences Faculty Publications

Portulacaria afra L. is a dominant facultative CAM species growing in the Southeastern Cape of South Africa. P. afra is well adapted to regions of the Spekboom thicket in areas of limited and sporadic rainfall. P. afra populations occur in isolated drainages. We hypothesized the utilization of CAM would vary in the different populations in response to rainfall and temperature gradients. Carbon isotope composition can be used to determine the contribution of CAM in leaf tissue. P. afra leaves of populations were analyzed in transects running south to north and east to west in locations from the coast to elevations …

Assessing The Genetic Status And Factors Leading To The Decline Of The Roanoke Bass (Ambloplites Cavifrons), Jackman C. Eschenroeder

College of Graduate Studies: Theses & Dissertations

Although numerous factors have led to the staggering declines in freshwater biodiversity throughout the United States and the world, habitat alteration and introduced species pose some of the greatest challenges to conservation efforts. Learning more about how these two factors lead to the decline of an endemic organism could help prevent the future loss of unique species and the premature conclusion of evolutionary trajectories. Roanoke bass (Ambloplites cavifrons) is a sport fish endemic to portions of the Roanoke, Chowan, Tar, and Neuse river basins of North Carolina and Virginia. This species has been in decline for many years, …

Connecting The Dots: A Food Web Of The Lower Ogeechee River, Allison K. Lutz

College of Graduate Studies: Theses & Dissertations

The Ogeechee is a fifth order river that originates in the Georgia Piedmont region and flows through the Coastal Plain region in the Southeastern portion of the state. The Ogeechee is one of the last unregulated rivers in Georgia; allowing for studies to occur under a natural flow regime. To my knowledge, studies that incorporate fish into ecological networks (e.g., food webs) are yet to be developed for the Ogeechee River, thus, one of the main objectives of this research was to address this knowledge gap. Five fish species were collected from June 2016 to October 2016 in order to …

The Role Of Habitat Management In Shaping Predation, Animal Color, And Gene Flow In A Metapopulation Of Florida Scrub Lizards (Sceloporus Woodi), Richard William Orton

College of Graduate Studies: Theses & Dissertations

Anthropogenic disturbance is known to affect biological diversity at the community, species, and genetic levels. Habitat fragmentation, in particular, has been shown to impact predator abundance and distribution, impede dispersal, and augment genetic drift. In small populations, which often result from habitat fragmentation, the effects of human disturbance may be disproportionately expressed. Small populations are more susceptible to selection pressures and random drift because genetic and phenotypic frequencies can become rapidly fixed, in comparison to larger populations. In turn, fixation of maladaptive alleles or morphs can accelerate extinction. For example, cryptic color polymorphism can be maintained by apostatic selection, where …

Silver Nanoparticle Fate And Accumulation In The Aquatic Food Web Of Stream Microcosms, Stefan J. Petersen

College of Graduate Studies: Theses & Dissertations

Silver nanoparticles (AgNPs) are used in 25% of all nano-enabled products and applied for anti-microbial properties. Silver nanoparticles are discharged into aquatic environments through wastewater discharge, runoff, and chemical spills. Once in aquatic environments silver nanoparticles have the potential to harm aquatic organisms. While the fate of silver nanoparticles in lentic systems has been investigated, limited information is available for the fate of silver nanoparticles in flowing environments. The purpose of this study was to compare the fate of AgNPs following a one-time pulsed application simulating a chemical spill, or small repetitive applications simulating effluent discharge, in artificial stream communities …

Evolutionary Linkage Of Mimetic And Non-Mimetic Color Traits In A Coral Snake Mimicry Complex, John D. Curlis Jr

College of Graduate Studies: Theses & Dissertations

Color polymorphism in aposematic mimicry systems is a perplexing phenomenon for evolutionary biologists, as theoretically the benefits of converging on a model phenotype should constrain the evolution of phenotypic diversity in these systems (i.e., color polymorphism should not occur). Nevertheless, color polymorphism in mimicry systems is prevalent throughout many taxa. In some of these systems, the evolution of color polymorphism results in the existence of non-mimetic morphs, such as those that are cryptic. The case of ground snakes (Sonora semiannulata) is unique in that color polymorphism encompasses both mimetic and cryptic morphs, as well as individual mimetic and …

Quantification And Characterization Of Net Precipitation Bacterial Flux From A Subtropical Epiphyte-Laden Oak Forest, Preston Pound

College of Graduate Studies: Theses & Dissertations

Transport pathways of microbes between ecosystem spheres (atmosphere, phyllosphere, and pedosphere) represent major fluxes in nutrient cycles and have the potential to significantly affect microbially-mediated biogeochemical processes. We quantified a previously unexamined microbial flux from the phyllosphere to the pedosphere during rainfall via throughfall (rainfall dripping from the canopy and through gaps) and stemflow (rainwater funneled down the stem). Bacterial concentrations were quantified using flow cytometry and validated with quantitative Polymerase Chain Reaction (qPCR) assays for samples from a Quercus virginiana (oak)- forest with heavy epiphyte cover (Tillandsia usneoides, Spanish moss) in coastal Georgia (Southeastern USA). Bacteria concentrations …

A Population Genetic Investigation Of The Reticulated Flatwoods Salamander (Ambystoma Bishopi) On Eglin Air Force Base, Alexander S. Wendt

College of Graduate Studies: Theses & Dissertations

The reticulated flatwoods salamander (RFS) is an endangered salamander with a unique life history. One of the largest known, best studied refuges for RFS is found on Eglin Air Force Base, and these RFS have been sampled and managed extensively since 2010. My thesis seeks to better understand RFS by using genetic techniques to address several unknowns, including: 1) determining the population structuring of RFS and the manageable units for species conservation, 2) estimating the size and status of populations, 3) understanding dispersal of RFS and factors that influence this, 4) exploring the breeding biology and recruitment patterns of RFS …