Digital Commons Network^™

How Do Prey Refuges Affect Predator-Prey Interactions?, Justin Vendettuoli

Senior Honors Projects

While it is well known that predators eat their prey, prey that avoid predation risk can also incur substantial fitness costs through risk-induced changes in survival and reproduction, growth, and morphology. Changes in prey that occur without the predator physically consuming the prey are referred to as ‘non-consumptive effects’. One way to reduce the risk of predation is to use a refuge. While refuge use may reduce predation risk, however, it may also be costly to the prey. These costs may include within-refuge competition for resources, which can alter prey population dynamics, coexistence, and metapopulation dynamics. While these costs may …

The Effects Of Fire On The Vernal Herbs Of An Eastern Mesic Forest, David Randolph Kem

Masters Theses & Specialist Projects

The effects of fire on vernal herbs of the mesic forests of eastern North America are poorly understood. I studied the influence of prescribed fire on species richness, abundance of rare and common species, and density of exotics in the vernal herbaceous layer. To determine these effects, three sites in central Kentucky were surveyed prior to and following one of three treatments: spring burn, winter burn, or negative control. I conducted low-intensity spring burns in April 2010 and winter burns in February 2011. I used chi square analyses to test for changes in species richness, abundance of rare species, abundance …

Differences In Population Structure Estimated Within Maternally- And Paternally-Inherited Forms Of Mitochondria In Lampsilis Siliquoidea (Bivalvia: Unionidae), Robert A. Krebs, W. Calvin Borden, Na'tasha M. Evans, F. Paul Doerder

Biological, Geological, and Environmental Faculty Publications

Mussels in several orders possess two separate mitochondrial lineages: a standard female-inherited form and one inherited only through males. This system of doubly uniparental inheritance (DUI) for mitochondrial genes provides an opportunity to compare the population structure of gene-lineages passed either mother-to-daughter or father-to-son. In the present study, we contrast variation in the male and female haplotype lineages of the American freshwater mussel species, Lampsilis siliquoidea (sometimes called Lampsilis radiata luteola), throughout the Lake Erie, Ohio River, and upper Mississippi River watersheds, and contrast variation with the sequences obtained for the related species/subspecies Lampsilis radiata radiata from Maine. The …

Nest Success And Habitat Choice Of Wilson's Plovers In Tom Yawkey Wildlife Center Heritage Preserve, South Carolina, Elizabeth Zinsser

All Theses

Little is known about the reproductive ecology of Wilson's Plover (Charadrius wilsonia). I conducted a study of nest site selection and nest success at a critical breeding area in South Carolina, USA. Data from other coastal nesting birds in the region suggest that a suite of environmental factors including flooding and predation may limit nest success in this region. To assess nest success rates of Wilson's Plovers in an area with limited human disturbance I monitored 72 nests during 2012 and 2013 on South Island and Sand Island located in Tom Yawkey Wildlife Center and Heritage Preserve. I measured environmental …

Taking The Road Most Travelled: Understanding Patterns Of Snake (Colubridae; Storeria) Movement And Road Mortality In A State Park, Iwo P. Gross

Undergraduate Honors Theses

No abstract provided.

Parentage Analysis And Conservation Genetics Educational Material For The Eastern Hellbender Salamander, Cryptobranchus Alleganiensis Alleganiensis, Sarah A. Chudyk

Master's Projects

Populations of the Eastern hellbender salamander, Cryptobranchus alleganiensis alleganiensis, are declining, making this a species of special concern in New York State and under consideration for Federal Endangered Species listing. As a result of this decline, the New York State Department of Environmental Conservation and the Buffalo Zoo initiated a headstarting program with an egg mass found in the Allegheny River drainage. The juveniles being raised by the Zoo will be released back into the watershed and so understanding the genetic diversity and parentage of these hellbenders will inform the reintroduction efforts. Furthermore, in order to determine how to …

Genetic Structure Of The Copperhead (Viperidae: Agkistrodon Contortrix Mokasen) At Its Most Northern Distribution, Brenna Aaren Levine

Graduate Theses and Dissertations

The focus of molecular studies in North American pitvipers has been on species that warrant conservation concern, such as Timber (Crotalus horridus) and Massasauga rattlesnakes (Sistrurus catenatus). Scant effort has been directed towards the molecular ecology of the Copperhead (Agkistrodon contortrix), other than to evaluate male reproduction in a laboratory setting and phylogenetic history. Thus, employing DNA-based molecular techniques to study the natural history of A. contortrix will broaden our knowledge of molecular ecology in North American pitvipers, and particularly in a non-threatened species that can serve as a surrogate for threatened and endangered …

The Life History Of Larinus Minutus, A Biological Control Agent Of Invasive Knapweeds, And Its Dispersal From Release Sites In Arkansas, Adam M. Alford

Graduate Theses and Dissertations

Larinus minutus Gyllenhal, a biological control agent of invasive knapweeds, has become established in several states and provinces since initial North American introduction in 1991. In order to reduce growing spotted knapweed populations in Northwest Arkansas, Larinus minutus (a biological control agent of spotted knapweed) was released annually from 2008-2011. Little is known about the larval development of this species, although the widespread use of this insect has provided research describing detailed host range and generalized life history. The speed and extent of the spread of this weevil from release sites following introduction have not been reported. This research described …

Ecology And Flock-Following Behavior Of The Wedge-Billed Woodcreeper In Eastern Ecuador, Abigail Darrah

Graduate Theses and Dissertations

The wedge-billed woodcreeper (Glyphorynchus spirurus) is a common understory suboscine passerine of lowland Neotropical rainforests. It frequently joins mixed-species understory flocks but also regularly forages alone, and thus is an excellent model species on which to conduct comparative behavioral observations to examine the hypothesized costs and benefits of flock-following. Individuals exhibit variable flocking propensities (proportion of time spent with flocks), and thus observing the correlations between flocking propensity and physical and environmental factors can provide further insight into the importance of flock-following to the ecology of this species. Despite its abundance at many sites and its wide geographic range, surprisingly …

A New Commons: Considering Community-Based Co-Management For Sustainable Fisheries, Charlotte L. Dohrn

Pomona Senior Theses

Commercial fisheries on the West Coast are traditionally managed under large-scale management and conservation plans implemented by state and federal agencies. This scale of management can present obstacles for fishing communities. This thesis examines emerging cases of attempts to define and implement sustainable management of commercial fisheries under a community-based co-management model. In Port Orford, Sitka, San Diego and Santa Barbara, preliminary community-based co-management models are enabling fishing communities to pursue social sustainability through preserving access, participating in local science, and direct marketing for fish products. These communities are actively reshaping traditional models of conceptualizing and managing common-pool resources like …

Amphibian Occupancy And Functional Connectivity Of Restored Wetlands In The Missouri River Floodplain, Michelle L. Hellman

School of Natural Resources: Dissertations, Theses, and Student Research

Wetland decline may threaten many taxa including shorebirds, amphibians, and fish. As agencies increase restoration of wetland habitat, monitoring is crucial to inform the process. Permeable skin sensitive to water quality and biphasic life histories requiring both terrestrial and aquatic habitat make amphibians good indicators of wetland health. I modeled amphibian occupancy in restored Missouri River bends to determine habitat characteristics associated with the presence of amphibians.

Occupancy modeling acknowledges imperfect detection and allows the inclusion of detection covariates. To assess detection I examined two methods currently used to assess anuran occupancy in wetlands, aural anuran surveys and tadpole dip-netting. …

A Multi-Scale Investigation Of Factors Limiting Bull Trout Viability, Tracy Bowerman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recent declines in many species of aquatic organisms have raised concerns about loss of biodiversity in river systems and the need to protect populations in peril. To conserve endangered species, scientists need to know information about the habitats organisms use throughout their life cycle and how environmental stressors cause populations to grow or decline. The goal of this research was to improve our understanding of the life-cycle requirements for bull trout (Salvelinus confluentus), a threatened freshwater fish species. I assessed environmental factors that affect bull trout egg incubation success and quantified juvenile bull trout movement patterns and survival …

Integrating, Developing, And Testing Methods To Generate More Cohesive Approaches To Biogeographic Inference, Mallory Elizabeth Eckstut

UNLV Theses, Dissertations, Professional Papers, and Capstones

As a fundamental component of the developing discipline of conservation biogeography, broadscale analyses of biotic assembly and disassembly across multiple temporal and spatial scales provide an enhanced understanding of how geologic transformations and climate oscillations have shaped extant patterns of biodiversity. As with any scientific field, there are limitations in the case of biogeographic historical reconstructions. Historical reconstructions are only as robust as the theoretical underpinnings of the methods of reconstruction (including data collection, quality, analysis, and interpretation). Nevertheless, historical reconstructions of species distributions can help inform our understanding of how species respond to environmental change.

My dissertation takes a …

Dispersal Ecology Of Desert Mosses Along Gradients Of Elevation, Wildfire Disturbance And Local Niche, Robert Joseph Smith

UNLV Theses, Dissertations, Professional Papers, and Capstones

Much of the variation in plant communities can be explained by the dispersal of individuals across landscapes, an ecological process that contributes to clinal variation, post-disturbance recovery and habitat occupancy. The role of dispersal is of particular concern for Mojave Desert plant communities that may not be able to tolerate recent departures from historical fire regimes. The aim of this thesis was to infer how dispersal is reflected by patterns of diversity in disturbed and undisturbed bryophyte communities in the Spring Mountains of southern Nevada. Chapter 2 presents an examination of sub-surface bryophyte communities (propagule "soil-banks") along a 1400 m …

The Evaluation Of Water Storage In Death Valley Using Grace Satellite Data, Maile Sweigart

UNLV Theses, Dissertations, Professional Papers, and Capstones

As drought conditions spread across the United States, concerns over water supplies, water use, and water management policies are growing and possible contributing environmental factors are continually being scrutinized. This thesis examines Death Valley as an analog for Southern Nevada and utilizes NASA EOS data, combined with ancillary climate data, to assess the effect of decadal climate variability on groundwater storage in the Death Valley area. Historical climate data, combined with satellite imagery observations, were compiled and calculated for analyses. Conclusions derived from statistical analyses infer trends between GRACE (Gravity Recovery and Climate Experiment) satellite data and fluctuating levels of …

The Affect Of Low Tide On The Digestion Of Balanus Glandula, The Acorn Barnacle., Jesse Osborn

Scripps Senior Theses

The rocky intertidal zone, experiencing fully marine and fully terrestrial conditions, has become increasingly investigated as a model ecosystem for studying the future implications of climate change. The barnacle, Balanus glandula, a common rocky intertidal inhabitant, plays an important role as a key prey item for many organisms. Low tide can be particularly challenging for barnacles as they are marine organisms subjected to the abiotic conditions of a terrestrial environment. The most stressful of these are increased temperature and decreased oxygen availability. This study aimed to investigate how low tide impacts the energy budget, specifically the digestion, of B. …

The Democratic Landscape: Envisioning Democracy Through Aldo Leopold's Land Ethic, Stacey L. Matrazzo

Master of Liberal Studies Theses

Since its founding, nature and nature-ownership have been central to American democracy, with property ownership remaining a fundamental part of its citizens' idea of liberty and freedom. Although initially constrained by common law principles, private property rights have varied over the centuries and have largely ignored the land's natural features. Landownership today tends to equate more with individual power than public responsibility. As a result of individualistic actions that have degraded the landscape and neglected the interdependence of humans with the greater biotic community, the divide between humans and nature has grown. In his groundbreaking essay, "The Land Ethic," Aldo …

Migrating Mule Deer: Effects Of Anthropogenically Altered Landscapes, Patrick E. Lendrum, Charles R. Anderson Jr., Kevin L. Monteith, Jonathan A. Jenks, R. Terry Bowyer

Natural Resource Management Faculty Publications

Background: Migration is an adaptive strategy that enables animals to enhance resource availability and reduce risk of predation at a broad geographic scale. Ungulate migrations generally occur along traditional routes, many of which have been disrupted by anthropogenic disturbances. Spring migration in ungulates is of particular importance for conservation planning, because it is closely coupled with timing of parturition. The degree to which oil and gas development affects migratory patterns, and whether ungulate migration is sufficiently plastic to compensate for such changes, warrants additional study to better understand this critical conservation issue.
Methodology/Principal Findings: We studied timing and synchrony of …

A Multi-Gene Molecular Systematic Study Of The Kickxellomycotina, Including The Examination Of Two New Genes (Mcm7 And Tsr1) For Phylogenetic Inference, Eric Dennis Tretter

Boise State University Theses and Dissertations

Kickxellomycotina is a recently described subphylum of Fungi defined by the presence of a unique disciform septal pore with a lenticular plug. The relationship between members of the group has proven difficult to resolve with traditional methods due to the degree of morphological and ecological variation among taxa within the clade. Furthermore, existing phylogenetic studies have lacked either the taxonomic coverage or had insufficient phylogenetic resolution to reveal the evolutionary history of the group.

In chapter one, I investigate the phylogenetic utility of two single-copy protein-coding genes, MCM7 and TSR1, to improve phylogenetic resolution within the clade. Suitable primers were …

The Effects Of Starvation Selection On Drosophila Melanogaster Life History And Development, Lauren A. Reynolds

UNLV Theses, Dissertations, Professional Papers, and Capstones

In nature, animals may endure periods of famine to complete their life cycles. Starvation stress will increase in populations as climates around the world change. To predict how populations may respond to such a stress, laboratory experimentation becomes essential. The evolutionary process of adaptation, its innovations and their trade-offs, can be studied in populations experiencing starvation stress. For this purpose outbred populations ofDrosophila melanogasterwere selected for starvation resistance in the laboratory.

After 60+ generations of starvation selection the starvation-selected flies have gone from surviving 2-3 days without food to 12-14 days without food. How this amazing feat of resistance is …

Soil Moisture Recognition And The Spatial Distribution Of Storm Activity In The Mojave Desert Using High-Resolution Aster And Modis Imagery For Thermophysical Mapping, Russell J. Skuse

UNLV Theses, Dissertations, Professional Papers, and Capstones

Climate models suggest that the Mojave Desert ecoregion is vulnerable to becoming drier in the future, and as the human population grows and development increases, environmental stresses will likely increase. Determining the spatial distribution and variation of soil moisture on a regional scale is an essential component to climate change, hydrologic, and habitat analyses. Soil permeability and sediment stability are characteristics that have been shown to be measurable from remote sensing observations. The primary objective of this project is to map the mechanical composition of the surface materials in the Mojave Desert ecoregion with implications for soil permeability, sediment stability, …

The Effect Of Landlocking On Intestinal Aquaporin 1 Expression In Alosa Pseudoharengus (Alewife), Emily Funk

Honors Scholar Theses

To determine the role of intestinal aquaporin 1 (AQP1), a passive water absorption channel, in the evolution of osmoregulatory physiology, I examined the differential expression of intestinal AQP1 between anadromous and landlocked ecotype of alewife in response to seawater challenges. I cloned and sequenced AQP1 from intestinal tissue of the alewife, following which I quantified the relative expression of AQP1 in each ecotype using Real-Time qPCR. In response to an acute seawater (30ppt) challenge, the anadromous alewives showed an upregulation of intestinal AQP1, while the landlocked alewives did not show a significant increased in AQP1 expression. After …

Larval Performance And Kill Rate Of Convergent Ladybird Beetles, Hippodamia Convergens, On Black Bean Aphids, Aphis Fabae, And Pea Aphids, Acyrthosiphon Pisum, Travis M. Hinkelman, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Generalist predator guilds play a prominent role in structuring insect communities and can contribute to limiting population sizes of insect pest species. A consequence of dietary breadth, particularly in predatory insects, is the inclusion of low-quality, or even toxic, prey items in the predator’s diet. Consumption of low-quality prey items reduces growth, development, and survival of predator larvae, thereby reducing the population sizes of generalist predators. The objective of this paper was to examine the effect of a suspected low-quality aphid species, Aphis fabae (Scopoli) (Hemiptera: Aphididae), on the larval performance of an abundant North American predator, Hippodamia convergens (Guérin-Méneville) …

Characterization Of Aebp2 Mutant Mice, Arundhati Bakshi

Honors Capstones

No abstract provided.

Unexpected Phylogenetic Positions Of The Genera Rupirana And Crossodactylodes Reveal Insights Into The Biogeography And Reproductive Evolution Of Leptodactylid Frogs, Antoine Foquet, Boris Leonardo Blotto, Maximiliano Manuel Maronna, Vanessa Kruth Verdade, Flora Acuña Juncá, Rafael O. De Sá, Miguel Trefaut Rodrigues

Biology Faculty Publications

Despite major progress in deciphering the amphibian tree of life by molecular phylogenetics, we identified two questions remaining to be answered regarding relationships within Hyloidea, the clade of South American origin that comprises most extant anuran diversity. A few genera like Rupirana and Crossodactylodes have enigmatic phylogenetic positions, and relationships among major lineages within some families like Leptodactylidae remain ambiguous. To resolve these specific questions we used two approaches (1) a complete matrix approach representing >6.6 kb, including most major Hyloidea lineages (61 terminals) combining different methods of phylogenetic reconstruction and measures of node support; and (2) a supermatrix approach …

Predation And Behavioral Plasticity In Green Swordtails: Mate Choice In Females And Exploratory Behavior In Males, Andrew J. Melie

School of Biological Sciences: Dissertations, Theses, and Student Research

Two studies were carried out with green swordtails, Xiphophorus helleri, to investigate the effect of predation on swordtail behavior, and to determine how behavioral plasticity operates in both a mate choice and an anti-predator context. Male green swordtails vary in colorful conspicuous traits, e.g. the colorful dorsal fin and sword. Female swordtails have a preexisting bias for males with a sword, and prefer long-sworded males to short-sworded males, but this preference is plastic. The first study examined predator-related plasticity in the behavior of males differing in size. Smaller males showed greater behavioral plasticity; they were more active in the …

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 …

Effects Of Non-Surface-Disturbing Restoration Treatments On Native Grass Revegetation And Soil Seed Bank Composition In Cheatgrass-Invaded Sagebrush-Steppe Ecosystems, Alexandra D. Reinwald

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The sagebrush-steppe communities of the Great Basin have been dramatically transformed by the invasion of the non-native annual grass cheatgrass. In many areas of the Great Basin, this invasion has resulted in the loss of native plant species and ultimately the conversion to cheatgrass-dominated communities. As healthy sagebrush communities provide multiple ecosystem services such as diverse wildlife habitat, forage for cattle grazing, and water filtration, restoration of these communities is a high priority to landowners and land management agencies. Established perennial grasses can successfully compete with non-native annual grasses and increase the resistance of plant communities to invasion by non-native …

Self-Limitation As An Explanation For Species' Relative Abundances And The Long-Term Persistence Of Rare Species, Glenda Marie Yenni

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ecological theories often hinge on species interactions, or how the species in an area "see" other species with whom they have to share food and space. Despite the contributions theoretical coexistence models have made to our understanding of species coexistence, it can still be difficult to match these theories with data from real communities. For example, we know of many species that are very rare where they occur. Theory predicts that these species should quickly go extinct, but they do not. I use simulations and real data to show that rare species are rare because they are more self-limiting. Self-limitation …

Interspecific Interactions Between Penstemon Palmeri And Shrubs In The Arid Shrublands Of The Spring Mountains, Nevada, Jesse M. Poulos

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A project involving shrub removal was undertaken by the United States Forest Service in the Spring Mountains National Recreation Area (SMNRA) to reduce accumulated woody fuels, which can pose risks to human communities. The SMNRA is also home to a variety of species that occur within these fuel reduction boundaries and are protected under the Multiple Species Habitat Conservation Plan (MSHCP) of Clark County, Nevada. It is unknown how MSHCP covered species will respond to shrub removal. This research focuses on the interactions between shrubs and the herbaceous plant Palmer’s penstemon (Penstemon palmeri), one of many nectar sources …