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Bactericera Cockerelli: Range Expansion, Candidatus Liberibacter Solanacaerum Detection, And Microbial Community Analysis, Alex Arp

Biology Theses

The potato psyllid (Bactericera cockerelli) is an emerging pest of solanacious crops. Traditionally their range expanded from Guatemala north through the central United States and into southern California. Recent expansions have led to potato psyllids residing as far south as Nicaragua and as for north as Washington State. Potato psyllids were also accidentally imported into New Zealand. These expansions are alarming because potato psyllids transmit Candidatus Liberibacter solanacaerum (Lso), the bacteria associated with Zebra Chip disease in potato, which results in millions of dollars in damages annually. In this study, potato psyllid and Zebra Chip range expansion into Central America …

Ground-Truthing Maxent In East Texas Rivers, David F. Ford

Biology Theses

Unionid mussels are a guild of freshwater, sedentary filter-feeders, which play a critical role in freshwater systems. Mussels are currently experiencing a global decline in both species richness and abundance, due to invasive species, human alteration of water systems, and climate change. In North America, which is considered to have the highest global diversity of bivalve species, native mussels are currently declining rapidly with at least 37 species considered to already be extinct. If extant mussel species are to be preserved, then it is vital that conservation efforts be prioritized towards areas in which they are likely to be found. …

The Identity Of Rana Margaritifera Laurenti, 1768 (Anura, Bufonidae), Esteban O. Lavilla, Ulisses Caramaschi, José A. Langone, José P. Pombal Jr., Rafael O. De Sá

Biology Faculty Publications

Rana margaritifera was described by Laurenti in 1768 and currently is associated to the genus Rhinella, under the combination Rhinella margaritifera. Currently, the R. margaritifera species group consists of 16 recognized species. Further-more, many additional species have been suggested to exist in this group which highlights the ambiguity surrounding the identity of Rhinella margaritifera and impend further description of the species in this group. After an exhaustive bibliographic review, we concluded that the recent designation of a lectotype for R. margaritifera is invalid according with Art. 73, ICZN, 1999. Herein, we designate and provide the description of a …

Habitat Characterization, Habitat Use And Associated Growth Of Juvenile Spotted Seatrout (Cynoscion Nebulosus) In A Mississippi Bay System: Implications For Stock Enhancement Practices, Joseph Read Hendon

Dissertations

The spotted seatrout (Cynoscion nebulosus) is the most targeted recreational fishery species in Mississippi coastal waters. Consequently, the Seatrout Population Enhancement Cooperative stock enhancement program was initiated to investigate methods for supplementing this heavily exploited population. Given ecological data needs for both wild and hatchery-reared (HR) juveniles of the species, habitat mapping, directed sampling and a caging study were conducted. Submerged aquatic vegetation (SAV), oyster shell and non-vegetated substrates were mapped at water depths < 2 m in Point aux Chenes Bay, Mississippi, using a sidescan sonar, which provided more accurate estimations of habitat coverage, particularly for SAV, compared to point-based sampling. Applying habitat strata delineated from sidescan mapping, late-juvenile spotted seatrout [125 - 275 mm total length (TL)] were sampled in SAV, marsh-edge and non-vegetated habitats as part of a seasonal gill net survey conducted in 2011 and 2012. Spotted seatrout ranging from 138 to 485 mm TL were collected using a smallmesh gill net, and 65% of collected individuals fell within the targeted late-juvenile size range. Overall mean catch-per-unit-effort of C. nebulosus did not differ for abundance or biomass between years, but both metrics were significantly higher in SAV habitats. Employing cage enclosures that …

Advocacy For Marine Management: Contributions To A Policy Advocacy Initiative In The Maldives, Neal Collins

Capstone Collection

On June 5, 2009 a 42-­‐km2 area of coral reef situated in the Alif Dhaalu (South Ari) atoll of the Republic of Maldives was designated the South Ari Atoll Marine Protected Area (S.A. MPA) due to a globally significant whale shark aggregation site. The whale shark is notorious for its gargantuan size and docile nature, which has led to a burgeoning tourist industry that gives people the opportunity to swim with the gentle giants in tropical sites such as the Maldives. The S.A. MPA receives tens of thousands of visitors a year that engage in whale shark excursions, however, there …

Variations In Phenotypic Plasticity And Fluctuating Asymmetry Of Leaf Morphology Of Three Quercus (Oak) Species In Response To Environmental Factors, Joseph Kusi

Electronic Theses and Dissertations

Leaf morphology of Quercus (oak) species is highly variable and complicated confounded with phenotypic plasticity and fluctuating asymmetry (FA). However, the study of variation is mostly limited to leaf morphology. This study was extended to plasticity and FA variations in Q. alba (white oak), Q. palustris (pin oak), and Q. velutina (black oak). It was hypothesized that light exposure, individual trees, leaf position, and other leaf traits will influence variation in these species. Leaves were sampled from trees of these species and their morphological traits were measured. Absolute asymmetry of leaf width and area were determined and plasticity of each …

Examining Mitochondrial Genetic Diversity In A Population Of Eastern Hognose Snakes (Heterodon Platirhinos) In Cape Cod, Ma, Stephanie R. Parelli

Theses, Dissertations and Culminating Projects

The Eastern Hognose snake (Heterodon platirhinos) is a relatively poorly studied species found in the eastern half of the United States from southern New England and Ontario south along the Atlantic coast to Florida and west to Texas, Kansas, Nebraska, and South Dakota. In the Northeastern part of their range they are considered to be a species of regional conservation concern by the Northeast Endangered Species and Wildlife Diversity Technical Committee. They are protected by conservation measures in the states of Rhode Island, Connecticut, and Massachusetts, and are listed as endangered by the state of New Hampshire. The purpose of …

Seed Germination And Seed Bank Of Scutellaria Species, Jennifer O'Brien

Undergraduate Honors Theses

Florida skullcap, Scutellaria floridana Chapm. (Lamiaceae), is a federally threatened species found in the Florida Panhandle. Its habitat is a fire-prone, longleaf pine forest dominated by Aristida stricta Michx. var. beyrichiana (wiregrass). Other Scutellaria species used in the study are found in southeastern U.S., including two within the Florida Panhandle. The objective of this study was to compare several techniques to germinate seeds of Scutellaria incana, Scutellaria lateriflora, Scutellaria ovata ssp. ovata, and Scutellaria floridana, and to access the presence of a seed bank for S. floridana. For the germination study, Scutellaria later …

Arthropod Density In A Fragmented Urban Landscape Along The Northern Coast Of The Gulf Of Mexico, Anna E. Williams

Honors Theses

Ecologists once focused their research on “pristine” habitats that were considered untouched by human activity. As urbanization rapidly increases, the concept of pristine habitats becomes obsolete. Urban habitats must be studied in order to understand the ecology of our increasingly developed society. Rapid urbanization greatly affects coastal habitats. Popular real estate, strip malls, casinos, and resorts all fragment urban landscapes. Much of the northern coast of the Gulf of Mexico is a fragmented urban landscape caused by rapid development. That same coastal landscape is ecologically important and includes habitats important to many different organisms, among them intercontinental migratory songbirds that …

Influence Of Wind Turbines On Mammalian Occupancy Patterns, Brian P. Tanis

Master's Theses or Doctor of Nursing Practice

Wind energy is among the most rapidly growing energy industries in the United States, with support for development coming from both state and federal governments. While the industry depicts an environmentally friendly image, the addition of infrastructure associated with wind farms alters landscapes in novel ways. Numerous studies have documented impacts wind turbines have on bird and bat mortality; however, far less attention has been directed towards responses of non-volant, terrestrial organisms. Mammalian mesocarnivores are model organisms to assess the alteration of communities surrounding wind turbines as they respond to addition of turbines and human activity, addition and improvement of …

Transforming The South Carolina Botanical Garden, Amy Blackwell

All Dissertations

This dissertation addresses the question of how to transform a small to mid-sized public garden into a botanical garden capable of making a significant contribution to science. Botanical gardens have certain features that distinguish them from pleasure gardens and public parks. These include a scientific basis for collections, an emphasis on recording data on the plants in the collection, exchanging plant materials and data with other botanical gardens, and providing educational information to visitors. Gardens often have several missions, including conservation of rare and endangered species, botanical and ecological research, and involving the public through citizen science. I describe my …

Understanding Effects Of Changes In Land Use, Environmental Parameters, Habitat Characteristics On The Great Basin Aquatic Invertebrates Using Ecological Stoichiometric Theory, Knut Mehler

UNLV Theses, Dissertations, Professional Papers, and Capstones

Many freshwater ecosystems in the Great Basin have undergone dramatic alteration over the past decades due to groundwater withdrawal, water diversion and changes in land use. These changes have affected benthic food web dynamics by altering the availability of chemical key elements for primary and secondary producers, by loss of biodiversity and extinction of endemic species. However, only few studies are available that addresses the link between changes in land use, habitat characteristics and its effects on benthic macroinvertebrates (BMI) communities comprehensively and little attention has been given to integrating physiochemical aspects to link ecosystem functions.

This dissertation analyzes the …

Exploring Signals Of Historical Demography In Boreal Mammals Through Integration Of Statistical Conservation Phylogenetics, Taxonomy, And Comparative Phylogeography, Jason L. Malaney

Biology ETDs

Understanding how diversity is partitioned across the landscape can provide perspectives related to the environmental processes that have influenced the evolutionary history of organisms. This main idea, often termed phylogeography, serves as the backdrop to my research where I explore three broad concepts including historical biogeography, cryptic diversity and ecology, and conservation phylogenetics. I address various questions in each of these concepts by using a set of mammals that are associated with montane and mesic environments of North America. More specifically, I focus on the jumping mice (Zapodidae) to test hypotheses that scale to the broader community. This approach allows …

An Environmental History Of The Bear River Range, 1860-1910, Bradley Paul Hansen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The study of environmental history suggests that nature and culture change all the time, but that the rate and scale of such change can vary enormously. During the late 19th and early 20th centuries, Anglo settlement in the American West transformed landscapes and ecologies, creating new and complex environmental problems. This transformation was particularly impressive in Cache Valley, Utah's Bear River Range. From 1860 to 1910, Mormon settlers overused or misused the Bear River Range's lumber, grazing forage, wild game, and water resources and introduced invasive plant and animal species throughout the area.

By the turn of the 20th century, …

Integrated Management Of Downy Brome (Bromus Tectorum L.) Infested Rangeland, Heather Elwood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Invasive weed species are a threat to the health and functionality of many rangeland systems. Downy brome (Bromus tectorum) is an invasive annual grass that affects the productivity of rangelands by decreasing the grazing capacity for livestock as well as altering the wildfire cycle and competing against more desirable vegetation for limited resources.

In 2006, an Invasive Plant Management Plan and Environmental Assessment was approved for Dinosaur National Monument, calling for prioritization of invasive species management on high value wildlife habitat, vector areas, and for species with a high ecological impact. The Cub Creek Watershed was identified as a priority …

Forest Recovery, Nutrient Cycling And Carbon Sequestration In A Southern Appalachian Spruce-Fir Forest, Patrick T. Moore

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Our forests provide us with a variety of services from clean water, forest products and wildlife habitat to the lesser known functions of nutrient cycling and carbon
sequestration. This research helps to demonstrate the extent of some of these services in a heavily disturbed southern Appalachian spruce-fir forest within Great Smoky Mountain National Park, the most heavily visited National Park in the United States. Following a catastrophic infestation of the non-native balsam wooly adelgid, the future of this forest was unknown, causing some to speculate about the future of this sensitive forest type. Though predictions about this forest’s future varied …

A Data-Intensive Assessment Of The Species Abundance Distribution, Elita Baldridge

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One of the most commonly observed patterns in ecology is the fact that at most locations there are a large number of relatively rare species, composed of only a few individuals per species, and a small number of relatively common species. This pattern of commonness and rarity is quantified by the species abundance distribution. As one of the most commonly observed patterns in ecology, it has been studied intensively for over 100 years.

A major emphasis of this research has been developing models to try to understand the forces that generate such a general pattern. As a result, there are …

Activities Of Methionine-Γ-Lyase In The Acidophilic Archaeon “Ferroplasma Acidarmanus” Strain Fer1, M. A. Khan, Madeline M. Lopez-Munoz, Charles W. Kaspar, Kai F. Hung

Faculty Research & Creative Activity

Biogeochemical processes on exposed pyrite ores result in extremely high levels of sulfuric acid at these locations. Acidophiles that thrive in these conditions must overcome significant challenges, including an environment with proton concentrations at pH 3 or below. The role of sulfur metabolism in the archaeon “Ferroplasma acidarmanus” strain fer1’s ability to thrive in this environment was investigated due to its growth-dependent production of methanethiol, a volatile organic sulfur compound. Two putative sequences for methionine- γ-lyase (EC 4.4.1.11), an enzyme known to carry out α,γ-elimination on L-methionine to produce methanethiol, were identified in fer1. Bioinformatic analyses identified a conserved pyridoxal-5′-phosphate …

Seed Germination And Seed Bank Of Scutellaria Species, Jennifer O'Brien

Student Honors Theses

Florida skullcap, Scutellaria floridana Chapm. (Lamiaceae), is a federally threatened species found in the Florida Panhandle. Its habitat is a fire-prone, longleaf pine forest dominated by Aristida stricta Michx. var. beyrichiana (wiregrass). Other Scutellaria species used in the study are found in southeastern U.S., including two within the Florida Panhandle. The objective of this study was to compare several techniques to germinate seeds of Scutellaria incana, Scutellaria lateriflora, Scutellaria ovata ssp. ovata, and Scutellaria floridana, and to access the presence of a seed bank for S. floridana. For the germination study, Scutellaria lateriflora and S. ovata ssp. ovata were stratified …

A Pharm-Ecological Perspective Of Terrestrial And Aquatic Plant-Herbivore Interactions, Jennifer Sorensen Forbey, M. Denise Dearing, Elisabeth M. Gross, Colin M. Orians, Erik E. Sotka, William J. Foley

Biology Faculty Publications and Presentations

We describe some recent themes in the nutritional and chemical ecology of herbivores and the importance of a broad pharmacological view of plant nutrients and chemical defenses that we integrate as “Pharm-ecology”. The central role that dose, concentration, and response to plant components (nutrients and secondary metabolites) play in herbivore foraging behavior argues for broader application of approaches derived from pharmacology to both terrestrial and aquatic plant-herbivore systems. We describe how concepts of pharmacokinetics and pharmacodynamics are used to better understand the foraging phenotype of herbivores relative to nutrient and secondary metabolites in food. Implementing these concepts into the field …

Functional Annotation And Comparative Analysis Of A Zygopteran Transcriptome, Alexander G. Shanku, Mark A. Mcpeek, Andrew D. Kern

Dartmouth Scholarship

In this paper we present a de novo assembly of the transcriptome of the damselfly (Enallagma hageni) through the use of 454 pyrosequencing. E. hageni is a member of the suborder Zygoptera, in the order Odonata, and Odonata organisms form the basal lineage of the winged insects (Pterygota). To date, sequence data used in phylogenetic analysis of Enallagma species have been derived from either mitochondrial DNA or ribosomal nuclear DNA. This Enallagma transcriptome contained 31,661 contigs that were assembled and translated into 14,813 individual open reading frames. Using these data, we constructed an extensive dataset of 634 orthologous nuclear protein-encoding …

Low Mortality In Tall Tropical Trees, R. Q. Thomas, J. R. Kellner, D. B. Clark, D. R. Peart

Dartmouth Scholarship

The dynamics of the tallest trees in tropical forests are of special interest due to their carbon content, canopy dominance, and the large canopy gaps created when they die. Known ecological mechanisms that may influence tall tree survival lead to conflicting predictions. Hydraulic stress and exposure to high winds and desiccation should increase death rates, yet the tallest trees have the greatest access to light and escape damage caused by falling boles and branches. The uncertainty in tall tree mortality rates has been difficult to address due to their low density, which makes mortality rates challenging to estimate accurately. Here, …

An Informational Algorithm As The Basis For Perception-Action Control Of The Instantaneous Axes Of The Knee, Wangdo Kim, Margarida M. Espanha, António P. Veloso, Duarte Araújo, Filipa João, Luis Carrão, Sean S. Kohles

Mechanical and Materials Engineering Faculty Publications and Presentations

Traditional locomotion studies emphasize an optimization of the desired movement trajectories while ignoring sensory feedback. We propose an information based theory that locomotion is neither triggered nor commanded but controlled. The basis for this control is the information derived from perceiving oneself in the world. Control therefore lies in the human-environment system. In order to test this hypothesis, we derived a mathematical foundation characterizing the energy that is required to perform a rotational twist, with small amplitude, of the instantaneous axes of the knee (IAK). We have found that the joint’s perception of the ground reaction force may be replaced …

The Need To Address Black-Backed Jackal And Caracal Predation In South Africa, David L. Bergman, Ho De Waal, Nico L. Avenant, Michael J. Bodenchuk, Michael C. Marlow, Dale L. Nolte

Wildlife Damage Management Conference

Prior to 1990, the four provincial governments of South Africa had a variety of programs in place to manage predation by black-backed jackals and caracals through lethal and nonlethal management in close cooperation with livestock farmers. During the 1990s the official programmes were phased out due to a multitude of factors including lower predation rates. Today, thousands of livestock (primarily sheep and goats, but also cattle and wildlife) are lost each day in South Africa due to black-backed jackal and caracal predation. The actual numbers are not known because not all losses are accounted or reported. It also does not …

Fish Assemblages Associated With Natural And Anthropogenically-Modified Habitats In A Marine Embayment: Comparison Of Baited Videos And Opera-House Traps, Corey B. Wakefield, Paul Lewis, Teresa B. Coutts, David V. Fairclough, Timothy J. Langlois

Fisheries Research Articles

Marine embayments and estuaries play an important role in the ecology and life history of many fish species. Cockburn Sound is one of a relative paucity of marine embayments on the west coast of Australia. Its sheltered waters and close proximity to a capital city have resulted in anthropogenic intrusion and extensive seascape modification. This study aimed to compare the sampling efficiencies of baited videos and fish traps in determining the relative abundance and diversity of temperate demersal fish species associated with naturally occurring (seagrass, limestone outcrops and soft sediment) and modified (rockwall and dredge channel) habitats in Cockburn Sound. …

Ecological Studies Of Wolves On Isle Royale, 2012-2013, John A. Vucetich, Rolf O. Peterson

Ecological Studies of Wolves on Isle Royale

Annual Report 2012-2013

Loggerhead Shrike (Lanius Ludovicianus): Species Conservation Assessment, Melissa J. Panella

Nebraska Game and Parks Commission: Publications

The primary goal in the development of at-risk species conservation assessments is to compile biological and ecological information that may assist conservation practitioners in making decisions regarding the conservation of species of interest. The Nebraska Natural Legacy Project recognizes the Loggerhead Shrike (Lanius ludovicianus) as a Tier I at-risk species. Here, I provide some general management recommendations regarding Loggerhead Shrikes. However, conservation practitioners will need to use professional judgment for specific management decisions based on objectives, location, and site-specific conditions. This resource provides available knowledge of Loggerhead Shrikes that may aid in the decision-making process or in identifying research needs …

Potential Effects Of Hydrogen Sulfide And Hydrocarbon Seeps On Mammoth Cave Ecosystems, Rick Olson

Mammoth Cave Research Symposia

Recently, Mammoth Cave Guide Bruce Hatcher reported what appeared to be contaminated water seeping into Marianne’s Pass. I visited the site and concluded that it was not likely due to pollution, and that it was a natural phenomenon. To be sure, I sampled the water for fecal coliform and E. coli analyses since sewer lines are in the area. The results were <1 mpn/100ml in both cases. A sulfur spring is mentioned at this site in Rambles in the Mammoth Cave, which was published in 1845, and this predates any well drilling that could lead to hydrocarbon and sulfide pollution. Another line of evidence that the seeps are natural is that they are all deeply weathered into the bedrock, which takes a long time. The seeps support thousands of springtails, which feed on the microbial mats, and crickets are common as well. A possible effect on biodiversity will be discussed.

Spill Retention And Routine Runoff Filtration Structures On Interstate 65 In The Vicinity Of Mammoth Cave National Park, Rick Olson

Mammoth Cave Research Symposia

In the early 70’s, I conducted an ecological study on the Doghill-Donahue Cave System in Southern Indiana. This cave remained relatively un-impacted until Highway 37 was widened near Bedford, and the cave was engineered to be a storm sewer for highway runoff . The consequences of facilitated water entry and easy access for spelunkers via an ungated culvert entrance were severe. Sediments washed into the cave smelled like putrid rubber when disturbed, habitat for cave life was trampled, and beautiful delicate mineral features were smashed. Anticipating that I-65 would someday be widened, I was concerned about possible consequences to Mammoth …

Antibiotic Resistance And Substrate Utilization By Bacteria Affi Liated With Cave Streams At Diff Erent Levels Of Mammoth Cave, Petra Byl, Shannon R. Trimboli, Rick Toomey, Jacob Byl, David Solomon, Tom Byl

Mammoth Cave Research Symposia

Located in south-central Kentucky, Mammoth Cave is one of the most unique National Parks in the United States. The surface landscape includes complex relationships between the flora and fauna along with human influences. However, the primary ecological focus is concealed below ground. Over four-hundred miles of cave passages, created by fl owing groundwater over millions of years, host a variety of macro and micro organisms. The Green River has cut into the limestone formation over geologic time, creating a complex network of passages that are stacked, one below the other, with the newer levels of cave lying near the bottom. …