Physical Sciences and Mathematics Commons^™

From Mountain Streams To Urban Rivers: An Assessment Of Microplastic Sources And Characteristics, Macy Gustavus

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plastic products are produced and discarded at an alarming rate. Bottles, bags, toys, and clothing break down into tiny plastic pieces called microplastics, ranging in size from an eraser on the top of a pencil to smaller in size than a red blood cell. Microplastics are becoming so common in the environment that they travel in the atmosphere, rivers, and ocean currents in ways that are similar to other types of Earth Systems Cycles (i.e., the water cycle). In this study, we explored microplastic sources and sinks in a freshwater river system and how seasonal changes in discharge affect how …

Comparing Fecal Dna Capture-Recapture Methods To Traditional Mark-Resight Methods For Estimating Abundance Of Mule Deer On Winter Ranges, Andi M. Stewart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Well-designed monitoring strategies are required to obtain accurate estimates of population abundance, which is important for evaluating conservation and management strategies. Obtaining abundance estimates using traditional survey methods, like aerial surveys, is not possible in all scenarios and can be expensive and risky. One survey method that has gained popularity in the last decade is fecal DNA-based capture-recapture (CMR). However, this method has not been evaluated on winter ranges or in snowy, winter conditions.

My first objective was to implement fecal DNA CMR to estimate abundance of mule deer in the Round Valley and Goodale winter survey areas in the …

Evaluation Of Best Practices For Urban Water Conservation And Water-Smart Growth Implementation In Utah, J. Ivy Harvey Thomson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Policies and programs have been utilized throughout the United States (U.S.) to reduce water use as a strategy to ensure sufficient water supplies for future demand. As governmental leaders and policy makers face increasing freshwater scarcity and supply unpredictability, along with rising costs and decreased federal funding, Best Practices (BPs) in water conservation are increasingly important to facilitate decision-making in choosing which strategies to employ. This project uses policy analysis to review and summarize various BPs, referencing both academic and professional literature. National fixture efficiency standards enacted in 1992 are credited as among the leading factors reducing indoor water use …

A Model Explaining Medusahead Invasion And Novel Targeted Grazing Approaches Of Control, Casey N. Spackman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Medusahead (Taeniatherum caput-medusae (L.) Nevski) is currently one of the biggest threats to rangelands and livestock operations in the Western US. High silica concentrations in medusahead contribute to its invasiveness. I developed a model to explain how silica is involved in the invasion process, and attempted to manipulate silica to increase use of the grass by livestock. Experiments were conducted to determine: 1) whether rotational grazing on established forages of improved nutritional quality would provide supplemental nutrients to increase cattle use of medusahead; 2) evaluate intake of and preference for medusahead treated with a glyphosate herbicide at different rates …

Why Do They Do That? Understanding Factors Influencing Visitor Spatial Behavior In Parks And Protected Areas, Abigail M. Sisneros-Kidd

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Visitors to parks and protected areas within the United States and worldwide often visit these areas with a particular destination in mind, such as seeing Old Faithful erupt in Yellowstone National Park or standing on the rim of the Grand Canyon in Grand Canyon National Park. These visitor use destinations, and the pathways leading to them, such as trails and roadways, see high levels of use, and as a result, impacts to soil, vegetation, air, water, soundscapes, and night skies that result from this use. The field of recreation ecology studies these impacts to park and protected area resources resulting …

Breeding Season Ecology And Demography Of Lesser Scaup (Aythya Affinis) At Red Rock Lakes National Wildlife Refuge, Jeffrey M. Warren

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

It is hypothesized that individuals make reproductive decisions based on current assessments of their physiological condition and environmental conditions. For female lesser scaup (Aythya affinis), breeding occurs after an energetically costly spring migration. Increasing fat reserves (i.e., ‘body condition’) prior to breeding allows a female to produce a larger clutch of eggs, but time spent gaining body condition is costly in terms of time allowed to raise ducklings before freezing conditions in the fall. In Chapter 2 I explored rate of pre-breeding body condition gain in female lesser scaup, and how that rate influenced clutch size. Spring phenology, …

Aligning Conservation Goals And Management Objectives For Bonneville Cutthroat Trout (Oncorhynchus Clarki Utah) In The Logan River, Utah, Harrison E. Mohn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rivers are often managed without informed knowledge of how sportfish use different areas of the river to reproduce, and rarely take into account the relationship between fish movement and how they are distributed within the river when making management decisions. The population of native Bonneville cutthroat trout (Oncorhynchus clarki utah) within the Logan River is the largest documented population remaining for this imperiled species, and still maintains extremely high numbers of fish in the upper river. Currently, fishing is not allowed in the upper 20 kilometers of the Logan River watershed during spawning, based on the assumption that …

Modeling Habitat Use Of A Fringe Greater Sage-Grouse Population At Multiple Spatial Scales, Anya Cheyenne Burnett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greater sage-grouse (Centrocercus urophasianus; hereafter sage-grouse) are a prominent bird species of sagebrush-dominated landscapes across the western United States. Over the past 15 years, sage-grouse have gained international attention due to decreasing population trends despite management efforts. In 2010 the U.S. Fish and Wildlife Service designated this species as warranted for listing under the Endangered Species Act, but the listing was precluded by other species at higher conservation risk. Habitat loss, degradation, and fragmentation have been implicated as primary sources of declines in sage-grouse distribution and abundance. The Bald Hills population in southwestern Utah occupies an area with …

Factors Affecting Gunnison Sage-Grouse (Centrocercus Minimus) Conservation In San Juan County, Utah, Phoebe R. Prather

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Due to loss of habitat, Gunnison sage-grouse (Centrocercus minimus) currently occupy 8.5% of their presumed historical range. One population survives in Utah, occurring in San Juan County. The Gunnison Sage-grouse Rangewide Conservation Plan and the San Juan County Gunnison Sage-grouse Conservation Plan recommended management strategies to address identified conservation threats to the Utah population. I addressed three conservation strategies identified in the plans: 1) creation and enhancement of brood-rearing areas; 2) assessment of habitat conditions within the Gunnison Sage-grouse Conservation Area; and 3) prevention or reduction of perching events by avian predators on distribution line power poles.

From 2007-2009, I …

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 …

Critique Of A Wildlife Habitat Evaluation Method Applied To Residential Open Space, Sarah Rigard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To this date, little research has been done evaluating the quality of wildlife habitat provided by open space in residential areas. Quality wildlife habitat for the purposes of this study is defined as those areas which contain the physical and biological characteristics necessary to support native wildlife species of the region. This thesis critiqued a wildlife habitat assessment method used in a nationwide study of residential open space for the purpose of better understanding the research conducted by the study and to inform similar, future habitat evaluations of landscapes altered by human activity to accommodate residential land use. The methodology …

Simulated Browsing Impacts On Aspen Sucker's Survival And Growth, Koketso Tshireletso

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Western forests dominated by aspen (Populus tremuloides Michx.) are highly regarded by most resource managers for their ability to provide a variety of benefits (Bartos and Mueggler 1982, Mueggler 1988). They noted aspen to be beneficial for production of livestock forage, wildlife habitat, and scenic beauty, and they are a potentially valuable source of wood products. However, in the West, communities are concerned about the dwindling acreage of aspen. The decline of aspen has been partly attributed to excessive ungulate browsing (Smith et al. 1972, Collins and Urness 1983, Bartos and Campbell 1998). Long-term grazing exclosures have also revealed …

Effects Of Flow Augmentation On Channel Morphology And Riparian Vegetation In The Upper Arkansas River Basin, Colorado, Dewitt S. Dominick

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined historic change of riparian plant communities and fluvial geomorphic response of gravel-bedded streams and their floodplains to over 50 years of hydrologic disturbance. Four tributary basins of the Arkansas River were analyzed. Lake Creek, Clear Creek, and Cottonwood Creek are drainages similar in area, physiography, and vegetation composition. However, Lake Creek may receive an instantaneous discharge of approximately 28 m3sec^-1 from the Twin Lakes tunnel, over three times the normal flow of the stream during spring runoff. By contrast, Clear Creek and Cottonwood Creek, nonaugmented streams, were used as controls to compare the historic and present …

A Model Of Energy Expenditure In White-Tailed Jackrabbits (Lepus Townsendii) Based On Integrated Studies Of Energetics And Field Ecology, Gordon L. Rogowitz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Field and laboratory studies were conducted to develop a model of energy expenditure in a population of white-tailed jackrabbits (Lepus townsendii). Field work in southwestern Wyoming during 1985-87 showed that the breeding season commenced at snowmelt and ceased during late- July drought. Adult females reproduced relatively synchronously and produced a mean of three litters annually. Greatest fetal production occurred in the second litter period. Collections indicated a 1:1 sex ratio, few jackrabbits >2 years-old, and a density of 7 animals / km² in the population. Postnatal growth was sigmoidal, culminating in heavier adult females than males. Using …

The Visual Decision Making Process As A Technique For Redistributing Outdoor Recreation Use, Martha Gail Hahn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The demand for recreation on public lands has been growing steadily, resulting in undesirable impacts on certain resources as well as recreation experiences. The problem addressed by this research is the uneven distribution of recreational use that causes a concentration of impacts. This thesis describes the development and testing of a method to reduce the uneven/concentrated recreation use occurring on the public lands.

The basic objectives of the study were to determine the effectiveness of redistributing recreationists by the use of photographs and a decisional process using photographic information and to identify its potential as a tool in meeting management …

Relationship Between Rainfall And Storm Runoff For Selected Arizona Watersheds, Robert James Anderson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The relationship between rainfall and runoff was examined for twelve selected Arizona watersheds. Expedient runoff volume model coefficients and runoff curve number model parameters were examined using standardized structure, with modifications to adjust the model for small initial abstractions and large watershed storage capacity.

Forest-land management practices were examined for their effects on curve number coefficients. The effects of rainfall characteristics were also evaluated with respect to changes they induce in curve number populations.

Evaluations included a runoff fraction, a simple multiplier of storm volume to produce runoff volume. The accuracy of this model is promising for more permeable watersheds.

Evaluation Of Some Soil Loss Equations For Predicting Sheet Erosion, Douglas Joseph Trieste

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objectives of this study were (a) to apply sediment and associated plot data from various infiltrometer studies to the parameters in the Universal Soil Loss Equation, a modified version of the original Musgrave Equation, and a modified version of the original Universal Soil Loss Equation, and compare the computed results with the measured soil loss, (b) to suggest reasons for any differences between computed and measured soil loss, and (c) to suggest improvements for each equation so that it will give results near the measured soil loss. The data used consisted of 2805 infiltrometer plots collected by previous researchers …

Coyote-Food Base Relationships In Jackson Hole, Wyoming, John L. Weaver

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I measured three variables of coyote-food base relationships in Jackson Hole, Wyoming, during the period July, 1973, to July, 1975. Field work provided estimates of relative coyote and prey abundance as well as observations on coyote feeding behavior during winter. Laboratory analysis of 1,500 coyote scats revealed feeding patterns while feeding trials with captive coyotes allowed refinement in interpretation of scat analysis.

Deer mice and chipmunks comprised most of the rodent biomass captured in traps in the fall, while ground squirrels accounted for much of the rodent biomass in the spring. Field voles declined from 1973 to 1974 throughout much …

Population Dynamics And Harvest Of Canada Geese In Utah, John Tautin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A twenty-one year (1952-72) accumulation of banding data for Canada geese in Utah was studied to determine the distribution and chronology of the harvest of the geese and the effects that hunting regulations have had upon harvests and population parameters. The banding data were also used in an attempt to develop a population model capable of predicting population trends and desirable survival rates.

Within Utah, the bulk of the annual harvest (78 percent) takes place in the northern portion of the State in the vicinity of the Great Salt Lake marshes. In Northern Utah the harvest peaks on the opening …

The Effects Of Flouride Ion On Some Blood Constituents Of Rainbow Trout, Salmo Gairdneri, Linnaeus, Richard H. Alger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During the past quarter of a century there has been considerable investigation into the effects of fluorides on living organisms. It has been well established, as a result of these studies, that both small and elevated amounts of fluorides present in the environment may have a marked toxic effect upon gaining entry into the organism. Much of the research involving fluorides and the living organism has been confined to experimentation with animals, although considerable evidence indicates that plants are also subject to injury if fluorides are present in the atmosphere or the soil.

The great majority of the research dealing …

Bird Studies Of The Bear River Marshes, Ernest W. Parkinson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The establishment of the Bear River Bay Bird Refuge has created for the state of Utah an immense and valuable biological field, a veritable paradise for naturalist and sportsman alike. The naturalist wants a place to study wild life and the sportsman desires game. With the proper control of open seasons on wild fowl the hunting instinct and incentive for the sport should be satisfied for the sportsman. To the naturalist this region will open up bountiful treasures of knowledge that is to be gained only by intense and prolonged scientific study.