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Prymnesium Parvum And Fish Kills In A Southern Nevada Man-~Made Reservoir, Tara Gregg

UNLV Theses, Dissertations, Professional Papers, and Capstones

The water chemistry of Lake Las Vegas (LLV), a Southern Nevada man-made reservoir, is influenced by both anthropogenic and natural sources. These sources affect the reservoir's water chemistry, which may promote harmful algal blooms (HABs) leading to massive fish kill events. Fish kills, caused by the golden algaePrymnesium parvum (P. parvum), continue to pose a threat in the reservoir. However, no effective treatments to controlP. parvumin large reservoirs such as LLV have been determined. This cross-sectional study evaluated important variables that may affectP. parvumHABs in LLV, including non-P. parvumbiomass (mg/m3), total zooplankton abundance (#/m3), temperature, TDS (salinity), mineral concentration (Ca, …

Pronghorn (Antilocapra Americana) Offspring Recruitment On The Carrizo Plain National Monument: Evaluating The Effects Of Low Population Density And Marginal Habitat Quality., Diego Ramirez Johnson

UNLV Theses, Dissertations, Professional Papers, and Capstones

Demographic fluctuation among ungulate populations is strongly linked to variability in recruitment. Rates of recruitment are subject to various forms of density-dependent and density-independent regulation. For species which benefit from the presence of conspecifics, reduced population density can decrease rates of recruitment and trigger a decline in per capita growth. Termed the Allee effect, this scenario can cause demographic collapse and population extinction. For many ungulate species, predation on juveniles is reduced when the timing and distribution of births is synchronized within a local population. Because birth synchrony is density-dependent, it may act as a mechanism for the Allee effect …

Population Response To Climate Change: Wintering Strategy Has Carryover Effects On The Timing Of Nest Initiation And Mate Choice In A Partial Migrant, The American Kestrel (Falco Sparverius), Alexandra Marie Anderson

Boise State University Theses and Dissertations

The ability of a population to respond to climate change will depend on phenotypic plasticity, adaptation, or both. Bird populations have already responded to warming temperatures by shifting their distributions, adjusting migration distance and timing, and breeding earlier. A population of American kestrels (Falco sparverius) in southwestern Idaho has advanced its nesting by approximately 30 days, on average, in the last 30 years and this has been correlated with changes in winter climate. The mechanisms allowing for this shift, however, are not clearly understood. I investigated if assortative mating of wintering kestrels and non-wintering kestrels is accompanying to …

The Role Of Vegetation Structure, Composition, And Nutrition In Greater Sage-Grouse Ecology In Northwestern Utah, Brian R. Wing

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The greater sage-grouse (Centrocercus urophasianus; sage-grouse) is the largest grouse species in North America and an indicator species for the condition of sagebrush (Artemisia spp.) ecosystems. The Box Elder Sage-Grouse Management Area (SGMA) in northwestern Utah encompasses one of the state’s largest sage-grouse populations.

To fill knowledge gaps regarding the population inhabiting the Raft River subunit of the Box Elder SGMA, I captured, radio-marked, and monitored 123 (68 female, 55 male) sage-grouse from January 2012 through December 2013. My purpose was to describe how the seasonal movements, survival, and reproductive rates of this sage-grouse population …

Paleozoic Seed Bank And Their Ecological Significance, Petra Seka Yehnjong

Electronic Theses and Dissertations

Soil seed banks are a reservoir of viable seeds present in the soil in plant communities. They have been studied and characterized in various ways in different habitats. However, these studies are limited to modern seed banks. This study extends seed bank studies to the Paleozoic Era. It was hypothesized that size distribution and seed density in Paleozoic seed banks exhibit similar patterns as in modern seed banks. Seed sizes and seed density of fossil seed from Wise Virginia were estimated. Modern seed bank information was obtained from published data. Data were analyzed using one-way ANOVA and Kruskal-Wallis test. The …

Diel Patterns Of Foraging Aggression And Antipredator Behavior In The Trashline Orb-Weaving Spider, Cyclosa Turbinata, James C. Watts

Electronic Theses and Dissertations

Few studies have rigorously assessed the adaptive value of diel rhythms in animals. We laid the groundwork for assessing the adaptive rhythm hypothesis by assaying diel rhythms of foraging and antipredator behavior in the orb-weaving spider Cyclosa turbinata. When confronted with a predator stimulus in experimental arenas, C. turbinata exhibited thanatosis behavior more frequently and for longer durations during the day. However, assays of antipredator response within webs revealed more complex diel patterns of avoidance behaviors and no pattern of avoidance behavior duration. Assays of prey capture behavior found that the likelihood of exhibiting prey capture behavior varied significantly …

Tactical Adjustment Of Signaling Leads To Increased Mating Success And Survival, Laura Sullivan-Beckers, Eileen A. Hebets

Eileen Hebets Publications

Most sexually reproducing animals overcome the challenge of searching for and attracting mates by utilizing signals that are broadcast through a spatially and temporally varying environment. A diverse suite of behavioral solutions exist for overcoming such environmental variability, including the adjustment of signaling behavior based upon receiver feedback. Few studies have directly examined the relationship between such tactical signaling adjustments and proxies of male fitness; the few that have, failed to find a relationship. Using the wolf spider, Schizocosa rovneri, we set out to first quantify among-male variation in the form and degree of responsiveness to female feedback. Following …

An Evaluation Of The Relative Performance Of Diploid Versus Triploid Brook Trout With Consideration Of The Influence Of Lake Characteristics, Andy Dean

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Brook trout are native to the east and Midwestern United States. Brook trout have become a popular sport fish in the western United States and are currently widely stocked to provide sport fishing opportunities throughout the west. The Utah Division of Wildlife Resources (UDWR) regularly stocks brook trout into high mountain lakes in the Uinta Mountains to provide one of these popular fisheries. Stocking non-natives to high mountain lakes can cause competition with native species for food and habitat resources and provides source populations for dispersal of non-natives downstream. Triploid (sterile) fish may provide an opportunity to stock non-native fish …

Plasticity In Female Mate Choosiness: A Result Of Variation In Perceived Predation Risk And The Interaction Of Female Age And Male Density, Ashley N. Atwell

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

In many species, female mate choices can be a strong source of sexual selection. Females often prefer a certain male phenotype, and this can be due to benefits females gain from mating with preferred males. However, such benefits can sometimes be outweighed by the cost of searching for a preferred male. These costs and benefits often change concomitantly with changes in environmental (e.g., predator abundance and conspecific density) and internal factors (e.g., female age). Thus, female mate choosiness (the degree to which preferences for certain males are expressed) should often be plastic. Plasticity in female mate choosiness may be complicated …

The Equitable Contributions Of Environment, Management And Restoration Status On Grassland Diversity And Composition, Raeann C. Powers

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

Plant composition is controlled by a combination of environmental, biotic, historical and management factors. Although there has been much focus on restoring grassland diversity, it is unclear which factors and/or interactions of factors are constraining diversity in grasslands and the relative influences of different factors. We measured soil fertility, soil texture, grazing intensity, fire frequency and plant cover in 694 plots, located within 33 remnant and restored fields in managed grasslands in the central Great Plains. Using univariate (general linear model) and multivariate (PERMANOVA) analyses, we identified significant factors and their relative contributions to plant richness, evenness, floristic quality index …

Adaptive Strategies For Foraging And Their Implications For Flower Constancy, Or: Do Honey Bees Multitask?, Ashley E. Wagner

Electronic Theses and Dissertations

Classical experiments on honey bee time-memory showed that foragers trained to collect food at a fixed time of day return the following day with remarkable time-accuracy. Previous field experiments revealed that not all foragers return to a food source on unrewarded test days. Rather, there exist 2 subgroups: “persistent” foragers reconnoiter the source; “reticent” foragers wait in the hive for confirmation of source availability. To examine how these foragers contribute to a colony’s ability to reallocate foragers across sources with rapidly changing availabilities, foragers were trained to collect sucrose during a restricted window for several days and observed over 3 …

Distribution And Drivers Of A Widespread, Invasive Wetland Grass, Phragmites Australis, In Great Salt Lake Wetlands, Arin Lexine Long

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Non-native invasive plant species can often have negative effects on native ecosystems, such as altered nutrient cycling, decreased habitat for wildlife, and outcompeting native plants. Around the Great Salt Lake (GSL), Utah, the invasive wetland grass Phragmites australis has become abundant in wetlands around the lake. Phragmites is replacing many native wetland plants provide important waterfowl habitat around the GSL. For successful management of Phragmites in GSL wetlands, it is important to know the current distribution of Phragmites, as well as areas that might be vulnerable to future invasion by Phragmites. To do this, we used multispectral aerial …

Ringtail Distribution, Dermatoglyphics, And Diet In Zion National Park, Utah, Adrian Argie Roadman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Current scientific knowledge of the ringtail (Bassariscus astutus) is limited, thus impeding appropriate management decisions. Ringtails in Zion National Park, Utah, are rarely seen, but are involved in increasing occurrences of negative interactions with park visitors and employees such as food theft and denning in buildings, interactions which are harmful to both parties. To manage this conflict, an update to the general knowledge about the status of the population is required as the only previous study on ringtails in this area was conducted in the 1960s. Using noninvasive techniques provides dependable large-scale population information. I used two noninvasive detection methods …

Use Of A Net Rate Of Energy Intake Model To Examine Differences In Juvenile Steelhead (Oncorhynchus Mykiss) Densities And The Energetic Implications Of Restoration, C. Eric Wall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Bonneville Power Administration (BPA) Fish and Wildlife Program mitigates for impacts of hydroelectric dams on ESA-listed salmon and steelhead populations in the Columbia River Basin (CRB). Considering the sizable investments in mitigation and the diversity of stream habitats within the CRB, there has been a pointed effort to develop and identify meaningful metrics relating to fish populations and trends in their habitat across the CRB. The Integrated Status and Effectiveness Monitoring Program (ISEMP) was developed in 2003 specifically for this purpose, and is tasked with developing and testing strategies for determining the status and trend of salmonid populations and …

Trophic Status, Energetic Demands, And Factors Affecting Lahontan Cutthroat Trout Distribution In Pyramid Lake, Nevada, Nicholas A. Heredia

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The progression of human development across the landscape has caused declines to both terrestrial and aquatic fauna. Many fishes, specifically native salmonids, have seen reductions in both population size and geographic distribution resulting from reduced habitat, overharvest, and the introduction of non-native predators and competitors. A native North American fish particularly hard hit by these types of actions, Lahontan cutthroat trout, are now limited to less than 10% of their historical habitat, and currently occupy only half of the lakes that they once occupied.

In Pyramid Lake, Nevada, where Lahontan cutthroat trout were once locally extinct, due to overfishing, water …

Macroinvertebrate-Driven Nutrient Recycling In Four Large Rivers, Matt A. Schroer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The cycling of nutrients is a fundamental process in streams and rivers, and scientists are increasingly recognizing the importance of animal communities to nutrient dynamics in these ecosystems. Despite growing evidence that animal excretion (i.e. urine) can supply limiting nutrients to primary producers in small streams, the importance of excretion is uncertain in large rivers. Accordingly, I used three estimation approaches based on past and new excretion rate data to determine nitrogen (N) and phosphorus (P) excretion inputs from insect communities in four large rivers (discharge > 10 cubic meters per second) in North America, and I compared these rates to …

The Ecosystem Role Of Fishes In Lotic Environments, Christopher C. Wheeler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

It is important for humans to understand how ecosystems work because we depend on them for a variety of products and services. For example, rivers and streams provide fisheries, improved water quality, and recreational opportunities to many individuals. In rivers, interactions among fishes, other stream plants and animals, and the physical river environment can influence continued provision of these valuable services. However, the role played by many freshwater fishes in the provision of these services remains unknown. Additionally, it is important to identify different factors that affect the outcome of interactions involving riverine fishes. To address these issues, I evaluated …

Estimating Baseline Population Parameters Of Urban And Wildland Black Bear Populations Using A Dna-Based Capture-Mark-Recapture Approach In Mono County, California, Jonathan L. Fusaro

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Prior to European settlement, black bear (Ursus americanus) were far less abundant in the state of California. Estimates from statewide harvest data indicate the California black bear population has tripled in the last 3 decades. Bears inhabit areas they formally never occurred (e.g., urban environments) and populations that were at historically low densities are now at high densities. Though harvest data are useful and widely used as an index for black bear population size and population demographics statewide, it lacks the ability to produce precise estimates of abundance and density at local scales or account for the numerous …

Influence Of Stand Composition On Soil Organic Carbon Stabilization And Biochemistry In Aspen And Conifer Forests Of Utah, Mercedes Román Dobarco

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Social concern about climate change and the elevated level of atmospheric CO2 demands understanding carbon (C) storage and dynamics in forest soils, especially since soils are the largest C reservoir in terrestrial ecosystems, storing two thirds of total C. Quacking aspen (Populus tremuloides Michx.) is an iconic species in western United States that offers multiple ecosystem services, such as habitat and forage for wildlife and cattle, biodiversity, water yield, and C storage. A decline in quaking aspen cover has been documented during the last decades, possibly due to fire suppression and ungulate browsing. A shift from aspen- to conifer-dominated …

Population Genetics And Microbial Communities Of The Gopher Tortoise (Gopherus Polyphemus), Daniel Lyle Gaillard

Dissertations

The gopher tortoise, Gopherus polyphemus, is an endangered species living in the southeastern United States. The recent and drastic decline in tortoise numbers has resulted in a multi-faceted approach to conserve this species. I used a population genetic approach to determine the population structure, genetic diversity and barriers to gene flow at a broad, regional and local scale. Tortoises are divided into five distinct genetic populations at the broad scale, the central populations have the highest levels of genetic diversity and the Tombigbee, Mobile, Apalachicola, Suwannee and St. John’s Rivers appear to be barriers to gene flow. At the regional …

Mafia Or Farmer? Coevolutionary Consequences Of Retaliation And Farming As Predator Strategies Upon Host Nests By Avian Brood Parasites, Mark E. Hauber

Publications and Research

Many host species of avian brood parasites have evolved to recognize and reject foreign eggs and chicks in the nest. Yet, other hosts accept and care for parasitic young, despite the fitness losses associated with raising non-kin. It has been suggested that nest predation upon host nests by brood parasites could select for coevolved acceptance by hosts, even when their cognitive and motor traits allow for the successful rejection of brood parasitism. Using a modeling approach, I analyzed the conditions that favor the evolution of two predatory strategies by parasites and the acceptance of parasitism in the presence of predatory …

Host Responses To Interspecific Brood Parasitism: A By-Product Of Adaptations To Conspecific Parasitism?, Peter Samas, Mark E. Hauber, Phillip Cassey, Tomáš Grim

Publications and Research

Background: Why have birds evolved the ability to reject eggs? Typically, foreign egg discrimination is interpreted as evidence that interspecific brood parasitism (IP) has selected for the host’s ability to recognize and eliminate foreign eggs. Fewer studies explore the alternative hypothesis that rejection of interspecific eggs is a by-product of host defenses, evolved against conspecific parasitism (CP). We performed a large scale study with replication across taxa (two congeneric Turdus thrushes), space (populations), time (breeding seasons), and treatments (three types of experimental eggs), using a consistent design of egg rejection experiments (n = 1057 nests; including controls), in areas with …

Hypogenic Versus Epigenic Subterranean Ecosystem: Lessons From Eastern Iberian Peninsula, Alberto Sendra, Policarp Garay, Vicente M. Ortuño, José D. Gilgado, Santiago Teruel, Ana Sofia P.S. Reboleira

International Journal of Speleology

Over the last 40 years, hypogenic karst/caves have become well known and hypogene speleogenesis has been used to explain the formation of some of the largest subterranean maze caves. These hypogenic systems involve confined aquifers with upwards flow, responsible for their karstification. Such spaces begun and could be remain isolated from the surface and the contiguous subterranean habitats, including the shallow ones. We studied the invertebrate fauna and the geology/speleogenesis of two recently opened caves from Eastern Iberian Peninsula, which clearly showed features of hypogenic origin. Their scarce faunistic composition, formed by non cave-adapted fauna, is similar to other hypogenic …

Body Size And Species Richness Changes In Glyptosaurinae (Squamata: Anguidae) Through Climatic Transitions Of The North American Cenozoic, Sara Elshafie

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Poikilothermic vertebrates offer excellent climate proxies based on relationships between environment and measurable variables such as body size and species richness. Relationships of these variables in lizards to environmental transitions over long time scales are poorly understood. Here I show that patterns of body size and species richness in a lizard clade, Glyptosaurinae (Squamata: Anguidae), correspond to known histories of paleotemperatures through the Cenozoic of North America. Glyptosaurines have the richest fossil record among North American Cenozoic lizards and exhibit a wide range of skull sizes. In order to estimate body size for glyptosaurines and other fossil anguids, I collected …

Fossil Crocodilians From The High Guajira Peninsula Of Colombia, And The History Of Neogene Crocodilian Diversity In Tropical South America, Jorge W. Moreno-Bernal

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The greatest diversity of Cenozoic crocodilians occurred during the Miocene in equatorial South America. However, the origin of this high diversity and its relationship to environmental factors are poorly understood. Most described species come from localities assigned to Laventan (13.8-11.8 Ma) and Huayquerian (9.0-6.8 Ma) South American land mammal ages (SALMAS), whereas the record is sparse in the early to middle Miocene and after the latest Miocene and Pliocene. Field research in the Castilletes (early Miocene-Pliocene) Formation in the High Guajira Peninsula of Colombia provides new fossil data on the origin of Neotropical crocodylian diversity. The Castilletes Formation crops out …

Sink Or Ecological Trap For Tree Swallows In Central Minnesota?, James T. Pathoulas, Nicole E. Noyes

Celebrating Scholarship & Creativity Day (2011-2017)

Background: An ecological trap is typically defined as a low-quality habitat, incapable of sustaining a population, which is preferred over a high quality habitat. Ecological traps may lead to species extinction in populations with 1) strict habitat requirements 2) minimal information about the habitat, and 3) low population size. Tree Swallows (Tachycineta bicolor) meet the former two of these criteria.

Methods: We monitored Tree Swallow (TS) nest boxes (n=90) at two ecologically similar sites A and B with similar occupancy rates. Site B has lower reproductive fitness —suggestive of an ecological trap. Binary logistic regression was used to …

Ecological Studies Of Wolves On Isle Royale, 2013-2014, John A. Vucetich, Rolf O. Peterson

Ecological Studies of Wolves on Isle Royale

Annual Report 2013-2014

Mapping The Spatial Movements, Behaviors, And Interactions Of Captive Orangutans Using Terrestrial Laser Scanning And Gis, Zachary Joseph Smith

USF Tampa Graduate Theses and Dissertations

Five captive Bornean orangutans (Pongo pygmaeus) were observed in order to better understand their spatial selection, behavior, and interaction with their environment and each other. A newly introduced adult male's interactions with a female group containing two adults, one adolescent, and one juvenile, was documented. Visual observations were performed to document individual behaviors, along with any interactions with silvery langur monkeys, public crowd levels, temperature, and enrichment props. Methods included 15 observation periods, 0.5-3 hours in length each, during which behaviors were verbally and visually confirmed using a HD video camera. Spatial locations of each individual were recorded every three …

Developing Transmissible Vaccines For Animal Infections: Intrinsically Safe Designs And A Staged Transparent Development Process Will Be Essential, Daniel G. Streiker, Megan E. Griffiths, Rustom Antia, Laura Bergner, Peter Bowman, Maria Vitoria Dos Santos De Moraes, Kevin Esvelt, Mike Famulare, Amy T. Gilbert, Biao He, Michael A. Jarvis, David A. Kennedy, Jennifer Kuzma, Carolyne Nasi,Iyu Wanyonyi, Christopher Remien, Tonie Rocke, Kyle Rosenke, Courtney Schreiner, Justin Sheen, David Simons, Ivet A. Yordanova, James J. Bull, Scott L. Nuismer

United States Department of Agriculture Wildlife Services: Staff Publications

Developing Transmissible Vaccines for Animal Infections: Intrinsically Safe Designs and a Staged Transparent Development Process Will Be Essential

Intrinsically safe, biologically compelling vaccine designs

Pahsed development must incorporate checkpoints and engagement

Staged development with established checkpoints

Wquitable partnerships with international governance

Toward deployment

Workshop organization

Seven proposed commitm ents for the responsible development of transmissible vaccines for infectious disease control in animals

Evolutionary outcomes of vaccine transmission depend on the viral vector and the genetic modifications introduced

Host-Parasite Interactions In An Invasive Songbird, Courtney A.C. Coon

USF Tampa Graduate Theses and Dissertations

Introduced species are the greatest threat to biodiversity after habitat loss. Understanding the processes that permit organisms to become successful invaders may provide opportunities to prevent or limit their dispersal and establishment and thereby alleviate some of their harmful effects. The goal of my dissertation research has been to investigate whether invasive species have distinctive interactions with parasites, and some of the mechanisms that may underlie that variation. I used one of the world's most successful vertebrate invaders as a case study: the house sparrow (Passer domesticus; Introduction).

Previous research in the house sparrow suggested that loss of …