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Introduced Sport Fish And Fish Conservation In A Novel Food Web: Evidence Of Predatory Impact, Kevin Lee Landom

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study addressed a fundamental question in applied ecology and conservation; what is the predatory impact of introduced piscivorous sport fish on imperiled native fish populations? More specifically, which of many introduced species and size-classes represent the greatest threats and should be targeted for control? In order to explore this important question, an integrated analysis of stable isotopes, quantified observed diet analysis, and stable isotope mass-balance models were used to quantify trophic interactions. These tools were used to construct food web models that were then compared to draw inferences regarding the relative contribution of prey fish, including rare native fish, …

Characterizing Ecologically Relevant Variations In Streamflow Regimes, Kiran J. Chinnayakanahalli

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Maintaining the ecological health of streams is vital for sustainable water resources management. Streamflow is a primary factor influencing the structure and function of ecological communities. A quantitative understanding of how stream biota respond to variation in streamflow is required for stream bioassessment. This dissertation focuses on quantifying relationships between streamflow regime and stream macroinvertebrate richness and composition. The contribution comprises statistical models that predict stream macroinvertebrate class from streamflow regime and predict streamflow regime from watershed attributes, and a tool that helps derive watershed attribute variables used in these models.

The dissertation is a collection of three papers. In …

Evaluation Of Semiochemical Strategies For The Protection Of Whitebark Pine Stands Against Mountain Pine Beetle Attack Within The Greater Yellowstone Ecosystem, Greta Katherine Schen-Langenheim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

High-dose verbenone, verbenone plus nonhost volatiles (NHVs), and both semiochemicals in combination with aggregant-baited funnel traps were tested for stand- level protection against mountain pine beetle attack for two consecutive years (2004-2005) at three seral high elevation whitebark pine sites in the Greater Yellowstone Ecosystem. In 2004, two 0.25-hectare treatments comprised of 25 high-dose verbenone pouches or verbenone pouches combined with single baited funnel traps were tested in a push-pull strategy. In 2005, 25 high-dose verbenone and 25 NHV pouches, or verbenone and NHV in combination with baited funnel trap clusters were tested. In both years, treatments were compared to …

Assessing Quaking Aspen (Populus Tremuloides) Decline On Cedar Mountain In Southern Utah Using Remote Sensing And Geographic Information Systems, Chad M. Oukrop

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Quaking aspen (Populus tremuloides Michx.) is the most widespread deciduous tree species in North America and aspen ecosystems are highly valued for multiple use, being noted for forage production, understory diversity, wildlife habitat, timber, hydrological assets, and aesthetics. However, aspen communities in the Intermountain Region of the western United States are in evident decline, with certain areas experiencing rapid mortality over the past decade. One location of special interest is the quaking aspen on Cedar Mountain in Southern Utah, USA, an isolated population in the southwestern portion of aspen's geographic range.

Lacking critical information on the location, extent, and …

Quantifying Legacy Effects Of Managed Disturbance On Sagebrush Steppe Resilience And Diversity, Julie Ripplinger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Land-use legacies can affect landscapes for decades to millennia. A long history of shrub management exists in the sagebrush steppe of the Intermountain West where shrub-removal treatments, a type of managed disturbance, have been implemented for over 50 years to reduce sagebrush cover. The assumption behind managed disturbances is that they will increase forage for domestic livestock and improve wildlife habitat. However, the long-term effects of managed disturbance on plant community composition and diversity are not well understood. We investigated the legacy effects of three common types of managed disturbance (chemical, fire, and mechanical treatments) on plant community diversity and …

Reproductive Ecology Of Astragalus Filipes, A Great Basin Restoration Legume, Kristal M. Watrous

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Astragalus filipes Torrey ex. A. Gray (Fabaceae) is being studied and propagated for use in rangeland restoration projects throughout the Great Basin. Restoration forbs often require sufficient pollination services for seed production and persistence in restoration sites. Knowledge of a plant's breeding biology is important in providing pollination for maximal seed set.

Reproductive output from four manual pollination treatments (autogamy, geitonogamy, xenogamy, and distant xenogamy) was examined in a common garden. Pod set, seed set, and seed germination were quantified for each of the treatments. Seed set from four wild populations was compared to that of an openly visited common …

Plastic And Genetic Determination Of Population, Community, And Ecosystem Properties In Freshwater Environments, Leigh C. Latta Iv

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The hierarchy of biological organization, from molecules to ecosystems, describes the relationships among various biological systems. Of particular interest is assessing how the factors that primarily determine the nature of one hierarchical level also have transcendent qualities that affect the ecology and evolution of higher hierarchical levels. The goal of this dissertation was to use a bottom-up approach to examine the transcendent effects of two factors that strongly determine the nature of their associated level of biological organization. The first, phenotypic plasticity, is a primary factor that determines the phenotype of an individual. The second factor, genetic diversity, largely determines …

The Effects Of Spruce Beetle (Coleoptera: Curculionidae: Scolytinae) On Fuels And Fire In Intermountain Spruce-Fir Forests, Carl Arik Jorgensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In spruce-fir forests, there are many biotic and abiotic disturbances that can alter stand structure and composition. Many of these disturbances can produce high percentages of tree mortality at different scales. Spruce beetle has been considered a devastating disturbance agent, capable of creating high levels of mortality that will alter fuel complexes that may affect fire behavior. For comparison, stand data were gathered in endemic (near Loa and Moab, UT), epidemic (near Loa and Fairview, UT), and post-epidemic (near Salina and Loa, UT) condition classes of spruce beetle activity. Generally, fine fuels were higher during the epidemic and returned to …

Comparative Ecology Of Narrowly Sympatric Horned Lizards Under Variable Climatic Conditions, Kevin V. Young

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We studied the Flat-tailed Horned Lizard, Phrynosoma mcallii, and the Sonoran Horned Lizard, P. goodei, in an area of narrow sympatry near Yuma, Arizona, and found they overlapped broadly in use of available food resources, body size, and growth rates. We compared diet (Chapter 2), growth and reproduction (Chapter 3), and survivorship (Chapter 4) of P. mcallii and P. goodei during two years of drought followed by a year of higher-than-average rainfall. We predicted that P. mcallii would be more tolerant of drought conditions than its congener, since P. mcalliiis found only in an extremely arid region while …

Maternal Effects In Transmission Of Self-Medicative Behavior From Mother To Offspring In Sheep, Udita Sanga

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mammals begin learning food preferences in utero and maternally mediated influences early in life help offspring develop their feeding habits. Mammals also learn by individual experience to ingest medicinal compounds such as polyethylene glycol (PEG), which attenuates the negative post-ingestive effects of tannins, a group of potentially toxic plant secondary compounds. The objective of this study was to investigate the transmission of acquired self-medicative behavior from mother to offspring using polyethylene glycol (PEG) as a medicine to relieve malaise caused by tannins. I hypothesized that: 1) mothers trained to associate the beneficial effects of PEG while consuming tannins will pass …

Evaluating Native Wheatgrasses For Restoration Of Sagebrush Steppes, Jayanti Ray Mukherjee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pseudoroegneria spicata and Elymus wawawaiensis are two native perennial bunchgrasses of North America's Intermountain West. Frequent drought, past overgrazing practices, subsequent weed invasions, and increased wildfire frequency have combined to severely degrade natural landscapes in the region, leading to a decline in the abundance of native vegetation. Being formerly widespread throughout the region, P. spicata is a favorite for restoration purposes in the Intermountain West. Elymus wawawaiensis, which occupies a more restricted distribution in the Intermountain West, is often used as a restoration surrogate for P. spicata. However, since most restoration sites are outside the native range of …

Genomic Perspectives On Evolution In Bracken Fern, Joshua P. Der

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The fern genus Pteridium comprises a number of closely related species distributed throughout the world. Collectively they are called bracken ferns and have historically been treated as a single species, Pteridium aquilinum. Bracken is notorious as a toxic weed that colonizes open fields and poisons livestock. Bracken is also easily cultured and has become one of the most intensively studied ferns. Bracken has been used as a model system for the study of the fern life cycle, fern gametophyte development, the pheromonal mechanism of sex determination, toxicology, invasion ecology, and climate change. This dissertation places bracken within a global …

Terrestrial Ecosystem Classification In The Rocky Mountains, Northern Utah, Antonin Kusbach

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Currently, there is no comprehensive terrestrial ecosystem classification for the central Rocky Mountains of the United States. A comprehensive classification of terrestrial ecosystems in a mountainous study area in northern Utah was developed incorporating direct gradient analysis, spatial hierarchy theory, the zonal concept, and concepts of diagnostic species and fidelity, together with the biogeoclimatic ecosystem classification approach used in British Columbia, Canada.

This classification was derived from vegetation and environmental sampling of both forest and non-forest ecosystems. The SNOwpack TELemetry (SNOTEL) and The National Weather Service (NWS) Cooperative Observer Program (COOP) weather station network were used to approximate climate of …

Natural History And Breeding System Of Maguire Primrose, Jacob B. Davidson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The goal of this thesis was to examine the breeding system and natural history of the Maguire primrose (Primula cusickiana var. maguirei). Maguire primrose is an endemic, threatened subspecies found only along a narrow corridor within Logan Canyon in northern Utah, USA. This plant displays distinct flower distyly, with clear distinction of pin and thrum morphologies (morphs). The timing of Maguire primrose flower blooms was disparate between upper and lower canyon populations, and the flowers experienced cool temperatures occasionally. I captured eight different species of flying insects visiting Maguire primrose flowers, and made 67 observations of insect visitation. …

The Effect Of In-Line Lakes On Dissolved Organic Matter Dynamics In Mountain Streams, Keli J. Goodman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research combines observation, experimentation, and modeling to evaluate the influence of lakes on dissolved organic matter (DOM) quantity, quality and export in subalpine watersheds of the Sawtooth Mountain Lake District, central Idaho.

First, I conducted an empirical study of the hydrologic and biogeochemical controls on DOM dynamics in stream-lake fluvial networks. I hypothesized that lakes would decrease temporal variability (i.e., buffer) and alter the characteristics of DOM from inflow to outflow. I tested these hypotheses by evaluating DOM temporal patterns and measuring annual export in seven-paired lake inflows and outflows. I then evaluated how ultraviolet (UV) exposure affected DOM …

Modeling Bark Beetle Outbreak And Fire Interactions In Western U.S. Forests And The Invasion Potential Of An Invasive Puerto Rican Frog In Hawaii Using Remote Sensing Data, Simon A. Bisrat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I used Moderate-Resolution Imaging Spectroradiometer (MODIS) imagery to answer two ecological questions. In the first project, I investigated the interactions between bark beetle-caused tree mortality and fire occurrence in western U.S. forests. I used remotely sensed fire data detected by MODIS satellite and bark beetle-caused tree mortality data. I tested the hypothesis that there is an increased probability of fire incidence in bark beetle-damaged forests compared to healthy forests using conditional probability modeling across the national forests of the western U.S. regardless of forest type. My results did not show a consistent pattern (increase or decrease of conditional probability of …

A Multi-Scale Evaluation Of Pygmy Rabbit Space Use In A Managed Landscape, Tammy L. Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Habitat selection has long been viewed as a multi-scale process. Observed species responses to resource gradients are influenced by variation at the scale of the individual, population, metapopulation, and geographic range. Understanding how species interact with habitat at multiple levels presents a complete picture of an organism and is necessary for conservation of endangered species. The main goal of this dissertation is to evaluate distribution, relative abundance, and habitat selection of a rare species, the pygmy rabbit Brachylagus idahoensis, at multiple scales in order to improve management and conservation for this species.

At the broadest scale, pygmy rabbit occurrence …

Zooplankton Population Dynamics In The Upper Mississippi River-Lake System, Krystal Michaels

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.

Habitat Assessment Of A Newly Established Breeding Pond For The Population Of Western Toads, Anaxyrus Boreas, At The Bernard Field Station, Erin Alison Baumler

Scripps Senior Theses

This study was the first research endeavor ever conducted concerning the population of Western toads, Anaxyrus boreas, at the Bernard Field Station. Despite the current lack of information regarding this population, they will become a concern in future years because they are threatened by habitat destruction. Preceding this study, a single breeding pond has been available to this population, which has been in use for the past 20 to 30 years. However, it is likely that the current breeding pond will be destroyed and the will be land developed for human use. In order to provide these toads with …

An Assessment Of The Potential Success Of Translocation As A Conservation Strategy For Western Toads (Anaxyrus Boreas) At The Robert J. Bernard Biological Field Station, Maya Higgins

Scripps Senior Theses

In response to imminent habitat destruction at the Robert J. Bernard Biological Field Station (BFS), translocation was assessed as a conservation strategy for a population of Western toads (Anaxyrus boreas). Currently, the BFS is home to a relatively unstudied population of Western toads, which rely on the existence of a seasonal breeding pond in open land owned by Harvey Mudd College on the west side of the field station. Unfortunately, there are plans to develop this plot of land within the next few years and so the breeding pond will be destroyed. In an effort to protect the …

Habitat Preference Of Nitrophila Species, Kari Hugie

Undergraduate Research Conference

Nitrophila occidentalis and Nirophlia mohavensis are both members of the same Family and Genus, and they both are found in the Great Basin region. They are the only members of the Genus Nitrophila native to the United States. Nitrophila occidentalisflourishes in the Great Basin, but Nitrophila mohavensis is endangered and limited to a few populations. Habitat analysis was done to the two species using GIS (Geographical Information Systems) to gain some new insight on how to preserve this endangered species. A discrete difference in soil alkalinity preference was found, which may help in saving N. mohavensis.

The Effects Of Food Quality On Preference And Incurred Risk In White-Tailed Deer (Odocoileus Virginianus), Travis Perlman, Jacob Stanton

Undergraduate Research Conference

An observational study was concluded in Nacogdoches County, Texas, to determine if free-range white-tailed deer (Odocoileus virginianus) could assess forage value. Multiple parameters were recorded to determine if individuals were willing to incur hight levels of risk as they sought to maximize their fitness, through dietary selection. Our results indicated that individuals were willing to incur higher levels of risk, in order to attain higher quality food items.

Ecological Niche Modeling And Local Knowledge Predict New Populations Of Gymnocladus Assamicus A Critically Endangered Tree Species, Shaily Menon, Baharul I. Choudhury, M. Latif Khan, A. Townsend Peterson

Peer Reviewed Publications

Gymnocladus assamicus is a critically endangered tree species endemic to northeastern India. Local inhabitants traditionally used this species for a variety of purposes. However, rapid population declines led to the species being considered extinct, until fieldwork in 2004 to 2007 identified 14 discrete populations of 1 to 7 trees each. To overcome constraints on field surveys imposed by the region’s remoteness and rugged terrain, we targeted areas of further field inventories by estimating the potential distribution of the species. Ecological niche modeling enabled us to identify 26 sites which the model predicted to be highly suitable for the species’ occurrence. …

Assessing Invasive Plant Species As Threats In Mojave Desert Parks, Sara L. Mcpherson, Donovan J. Craig, Scott R. Abella

Graduate Research Symposium (2010 - 2017)

The invasion and persistence of exotic plant species threatens the natural features that national parks are designed to protect. For example, park managers have witnessed an increase in the frequency, extent and intensity of fires along with a reduction in native species richness and diversity. Many park managers are familiar with a suite of highly invasive plants, but lack a comprehensive and systematic way of prioritizing invasive plant species based on potential threats to the parks’ resources. We have entered into a collaborative project with the National Park Service’s Inventory and Monitoring program to develop an invasive plant early detection …

29 Years Of Vegetation Community Change Across Environmental Gradients In A Mojave Desert Mountain Range, Christopher L. Roberts, James S. Holland, Scott R. Abella

Graduate Research Symposium (2010 - 2017)

There is a great deal of uncertainty as to how biological communities respond to changes in land use and climate change, a situation particularly relevant in protected areas such as national parks that were designated to conserve specific biological features. Utilizing extant vegetation data sets with repeatable methodology can provide opportunities for insight into previous vegetation change and provide base line data for long-term monitoring projects useful for modeling vegetation community trajectories. We have relocated and resurveyed 106 sites from a vegetation community study initiated in 1979 in the Newberry Mountains, southern Nevada, within Lake Mead National Recreation Area managed …

Tyrannobdella Rex N. Gen. N. Sp. And The Evolutionary Origins Of Mucosal Leech Infestations, Anna J. Phillips, Renzo Arauco-Brown, Alejandro Oceguera-Figueroa, Gloria P. Gomez, María Beltrán, Yi-Te Lai, Mark E. Siddall

Publications and Research

Background: Leeches have gained a fearsome reputation by feeding externally on blood, often from human hosts. Orificial hirudiniasis is a condition in which a leech enters a body orifice, most often the nasopharyngeal region, but there are many cases of leeches infesting the eyes, urethra, vagina, or rectum. Several leech species particularly in Africa and Asia are well known for their propensity to afflict humans. Because there has not previously been any data suggesting a close relationship for such geographically disparate species, this unnerving tendency to be invasive has been regarded only as a loathsome oddity and not a unifying …

Mathematical Modeling Of Optimal Seasonal Reproductive Strategies And A Comparison Of Long-Term Viabilities Of Annuals And Perennials, Anthony Delegge

Department of Mathematics: Dissertations, Theses, and Student Research

In 1954, Lamont Cole posed a question which has motivated much ecological work in the past 50 years: When is the life history strategy of semelparity (organisms reproduce once, then die) favored, via evolution, over iteroparity (organisms may reproduce multiple times in their lifetime)? Although common sense should dictate that iteroparity would always be favored, we can observe that this is not always the case, since annual plants are not only prevalent, but can dominate an area. Also, certain plant species may be perennial in one region, but annual in another. Thus, in these areas, certain characteristics must be present …

The Loss Of Species: Mangrove Extinction Risk And Geographic Areas Of Global Concern, Beth A. Polidoro, Kent E. Carpenter, Lorna Collins, Norman C. Duke, Aaron M. Ellison, Joanna C. Ellison, Elizabeth J. Farnsworth, Edwino S. Fernando, Kandasamy Kathiresan, Nico E. Koedam, Suzanne R. Livingstone, Toyohiko Miyagi, Gregg E. Moore, Vien Ngoc Nam, Jin Eong Ong, Jurgenne H. Primavera, Serverino G. Salmo, Jonnell C. Sanciango, Sukristijono Sukardjo, Yamin Wang, Jean Wan Hong Yong

Biological Sciences Faculty Publications

Mangrove species are uniquely adapted to tropical and subtropical coasts, and although relatively low in number of species, mangrove forests provide at least US $1.6 billion each year in ecosystem services and support coastal livelihoods worldwide. Globally, mangrove areas are declining rapidly as they are cleared for coastal development and aquaculture and logged for timber and fuel production. Little is known about the effects of mangrove area loss on individual mangrove species and local or regional populations. To address this gap, species-specific information on global distribution, population status, life history traits, and major threats were compiled for each of the …

Fun, Fun, Fun Till The Waters Take The Beaches Away, Briana Ellis

Maria Dittman Library Research Competition: Student Award Winners

No abstract provided.

An Entrepreneurial Approach To Librarianship, Flora Shrode, Jennifer Duncan, Wendy Holliday

Library Faculty & Staff Publications

Librarians from Utah State University explain recent efforts to encourage subject librarians to take a more holistic view of their roles. We are shifting from a traditional emphasis primarily on collection development and refocusing on natural connections between collections, instruction, liaison, and reference service. The poster provides background about Utah State University’s situation and explains our approach to analyzing local needs and culture to inform development of a new organizational structure. We describe our vision of subject librarianship, the process by which we assessed librarians’ ideas and goals for performing as subject librarians, and the actions we are taking to …