Digital Commons Network^™

Holdrege Fall Field Days, Janis Paseka

Nebraska Bird Review

The 2023 NOU Fall Field Days were held in Holdrege on September 22–24, with approximately 45 in attendance. The programs were held at the Rodeway Inn. The meeting was planned by Robin Harding, Jan Johnson, and Ruthie Stearns. Field trips were led by Robin Harding, Paul Dunbar, and William Flack to numerous locations including Johnson Lake SRA, Elwood Reservoir WMA, the eagle viewing site on the Phelps County Canal in northern Gosper Co., the Platte River bridge south of Overton, Cottonwood WPA, Harlan Co. Reservoir, the Alma water treatment plant, Funk WPA, Nature's Mosaic Recreation Area, and Sacramento-Wilcox WPA.

The …

Social Connections Across Migration: Do Golden- Crowned Sparrows (Zonotrichia Atricapilla) That Socialize In Winter Also Breed Together?, Theadora A. Block, Bruce E. Lyon, Zachary Milakonis, Alexis S. Chaine, Daizaburo Shizuka

School of Biological Sciences: Faculty Publications

Many birds that are territorial in the breeding season live in groups during the nonbreeding season, thereby gaining benefits such as protection from predators and increased access to resources. However, how the social connections in group life change across seasons in migratory animals is mostly unknown. We ask whether winter social connections continue during the breeding season in a migratory songbird. Golden-crowned Sparrows (Zonotrichia atricapilla) have distinct, stable winter communities that include both site and group fidelity across years: birds almost always rejoin the same social community each year after migration. If these birds have social connectivity across …

Rapid Evolution Of A(H5n1) Influenza Viruses After Intercontinental Spread To North America, Ahmed Kandeil, Christopher Patton, Jeremy C. Jones, Trushar Jeevan, Walter N. Harrington, Sanja Trifkovic, Jon P. Seiler, Thomas Fabrizio, Karlie Woodard, Jasmine C. Turner, Jeri Carol Crumpton, Lance Miller, Adam Rubrum, Jennifer Debeauchamp, Charles J. Russell, Elena A. Govorkova, Peter Vogel, Mia Kim-Torchetti, Yohannes Berhane, David Stallknecht, Rebecca Poulson, Lisa Kercher, Richard J. Webby

United States Department of Agriculture Wildlife Services: Staff Publications

Highly pathogenic avian influenza A(H5N1) viruses of clade 2.3.4.4b underwent an explosive geographic expansion in 2021 among wild birds and domestic poultry across Asia, Europe, and Africa. By the end of 2021, 2.3.4.4b viruses were detected in North America, signifying further intercontinental spread. Here we show that the western movement of clade 2.3.4.4b was quickly followed by reassortment with viruses circulating in wild birds in North America, resulting in the acquisition of different combinations of ribonucleoprotein genes. These reassortant A(H5N1) viruses are genotypically and phenotypically diverse, with many causing severe disease with dramatic neurologic involvement in mammals. The proclivity of …

The Floral Thermal Environment: Physical, Morphological, And Environmental Determinants, And Their Impact On Plant-Pollinator Interactions, Jennifer Apland

All Theses

Anthropogenic climate change is driving major shifts in global temperatures and increases in extreme temperature events that contribute to reduced survival and species loss. To counteract extreme temperatures, many organisms can undergo geographic range shifts or engage in behavioral thermoregulation (e.g., movement to suitable microhabitats). While plants are sessile and thus subject to highly variable ambient temperatures, they have evolved mechanisms to regulate internal floral temperature. Floral thermoregulation may mitigate thermal stress on pollen and ovules and impact plant-pollinator interactions. These mechanisms for thermoregulation are often highly dependent on ambient temperature and solar radiation as most plants are not endothermic. …

Effects Of Landcover On Mesocarnivore Density And Detection Rate Along An Urban To Rural Gradient, Leah E. Mctigue, Brett Degregorio

Biological Sciences Faculty Publications and Presentations

Human development has major implications for wildlife populations. Urban-exploiter species can benefit from human subsidized resources, whereas urban-avoider species can vanish from wildlife communities in highly developed areas. Therefore, understanding how the density of different species varies in response to landcover changes associated with human development can provide important insight into how wildlife communities are likely to change and provide a starting point for predicting the consequences of those changes. Here, we estimated the population density of five common mesocarnivore species (coyote (Canis latrans), bobcat (Lynx rufus), red fox (Vulpes vulpes), raccoon (Procyon …

Interactions Between Fitness Components Across The Life Cycle Constrain Competitor Coexistence, Miguel Gómez-Llano, Wade A. Boys, Taylor Ping, Simon P. Tye, Adam M. Siepielski

Biological Sciences Faculty Publications and Presentations

1. Numerous mechanisms can promote competitor coexistence. Yet, these mechanisms are often considered in isolation from one another. Consequently, whether multiple mechanisms shaping coexistence combine to promote or constrain species coexistence remains an open question.
2. Here, we aim to understand how multiple mechanisms interact within and between life stages to determine frequency-dependent population growth, which has a key role stabilizing local competitor coexistence.
3. We conducted field experiments in three lakes manipulating relative frequencies of two Enallagma damselfly species to evaluate demographic contributions of three mechanisms affecting different fitness components across the life cycle: the effect of resource competition on individual growth …

Effects Of Seasonal Environment On Abundance, Behavior, Visual Signaling, And Perception In Prairie Butterflies, Grace Elizabeth Hirzel

Graduate Theses and Dissertations

Phenotypic plasticity is a widespread mechanism that allows animals to respond quickly to seasonal changes in their environment. However, the depth and complexity of these plastic responses is still being discovered. One aspect of seasonal physiology that is relatively unstudied is changes to sensory physiology and how it may explain changes in behavior. To determine how changes in seasonal conditions affect behavior, coloration, and vision, I examined populations of wild butterflies in Northwest Arkansas. Focusing on a single species, the common buckeye Junonia coenia, I found that seasonal coloration covaries with thermoregulating behavior and is accompanied by changes in visual …

Human-Bat Interactions In A Disease Emergence Hotspot: Implications For Human Health And Bat Conservation, Reilly Tempest Jackson

Graduate Theses and Dissertations

Bats are an ecologically important taxon that can host zoonotic pathogens. Globally, many bat species are synanthropic and live closely with humans, often roosting in man-made structures. The spatial overlap between humans and bats creates opportunities for human-bat contact, which can lead to human exposure to bat-borne pathogens and conflicts that cause bat mortality. Despite this risk, little is known about the drivers and characteristics of these human-bat interactions in buildings and work is needed to understand this aspect of the wildlife-urban interface. In Chapter I, I present a literature review that identifies the geographic and taxonomic trends in reported …

Seagrass Epibiont Biodiversity In The Northern Gulf Of Mexico, Kathryn Wyssmann

LSU New Orleans Theses and Dissertations

Epibionts on seagrass leaves contribute substantially to productivity and trophic interactions in seagrass ecosystems. Differences in epibiont assemblages and factors that contribute to epibiont diversity have been little studied on the seagrass Halodule wrightii in the northern Gulf of Mexico (nGoM). We used a metabarcoding approach to describe epibiont assemblages on H. wrightii leaves in four bays across the nGoM and to test whether epibiont assemblages differed spatially at local levels (within bays) or regional levels (from west to east). Furthermore, we tested if epibiont diversity was related to environmental conditions and/or seagrass productivity. Epibiont assemblages differed significantly between bays …

How Beavers (Castor Canadensis) Affect Habitat Availability For Two Native Oregon Turtles: Actinemys Marmorata And Chrysemys Picta Bellii, Rodé Krige

University Honors Theses

Oregon is home to two native freshwater turtle species: the northwestern pond turtle and the western painted turtle. Both turtles are Oregon conservation strategy species with a status rating of sensitive, indicating declining populations. Oregon's decline in these turtle's populations is thought to be predominantly due to loss and degradation of habitat that results from development and urbanization. Beavers' ability to dam streams and create ponds may be creating habitat usable by turtles, but the relationship is under-studied. This study assessed water temperature, basking habitat, and overall turtle habitat suitability at beaver-dammed and control ponds in Portland, Oregon. Average basking …

Impacts Of Disturbance And Nutrient Addition On Coastal Dune Arthropod Communities, Kayla Beitzel

Honors Theses

Coastal dune ecosystems are globally distributed ecosystems that occur from the tropics to the poles and serve as the first line of defense during storms. They are critical habitats for a variety of organisms and also play a critical role in stabilizing coastal habitats. These systems face increased pressure via urban development, recreational expansion, and sea-level rise (Newman et al. 2023; Webster et al. 2005). Insects are vital consumers in coastal ecosystems and act as regulators of plant growth. Low-diversity ecosystems, like coastal dune systems, often contain a higher abundance of low-diverse insect consumers (Ripple et al. 2021), which can …

Breaking Virulent: The Coincidental Evolution Of Virulence Factors In Bacteria., Rhiannon Emmanuelle Cecil

Electronic Theses and Dissertations

Understanding how innocuous organisms can evolve to be pathogenic to humans is of increasing global concern. Further, understanding how existing pathogens may evolved to be more virulent is also vital to our ability to provide healthcare to people afflicted with diseases that promote chronic bacterial infections, such as cystic fibrosis. With the rise of antibiotic resistance in both bacteria and fungi it is paramount that new therapeutics are identified. Understanding what mutations occur that result in increased virulence in microbes can potentially provide new targets for antimicrobial drugs to combat antibiotic resistance. The Coincidental Evolution Hypothesis is a fundamental hypothesis …

Balancing Societal Demands For Agricultural Land: Insights, Innovations, And Conservation Priorities, Sarah Halperin

Boise State University Theses and Dissertations

With an increasing global population and the effects of climate change and biodiversity loss intensifying, society faces many challenges in reconciling conflicting demands for the landscape. Covering roughly half of the land area of the United States, agricultural land is in direct competition with other land uses and will likely play an important role in addressing these important conservation challenges. In this dissertation, we used well-supported existing methodologies and principles from ecosystem services, message framing, and biodiversity conservation to create knowledge about how to better protect agricultural lands. We conducted our study in the Treasure Valley, Idaho, where the issue …

Accelerated Evolution Of Sars-Cov-2 In Free-Ranging White-Tailed Deer, Dillon S. Mcbride, Sofya K. Garushyants, John Franks, Andrew F. Magee, Steven H. Overend, Devra Huey, Amanda M. Williams, Seth A. Faith, Ahmed Kandeil, Sanja Trifkovic, Lance Miller, Trushar Jeevan, Anami Patel, Jacqueline M. Nolting, Michael J. Tonkovich, J. Tyler Genders, Andrew J. Montoney, Kevin Kasnyik, Timothy J. Linder, Sarah N. Bevins, Julianna B. Lenoch, Jeffrey C. Chandler, Thomas J. Deliberto, Eugene V. Koonin, Marc A. Suchard, Philippe Lemey, Richard J. Webby, Martha I. Nelson, Andrew S. Bowman

United States Department of Agriculture Wildlife Services: Staff Publications

The zoonotic origin of the COVID-19 pandemic virus highlights the need to fill the vast gaps in our knowledge of SARS-CoV-2 ecology and evolution in non-human hosts. Here, we detected that SARS-CoV-2 was introduced from humans into white-tailed deer more than 30 times in Ohio, USA during November 2021-March 2022. Subsequently, deer-to-deer transmission persisted for 2–8 months, disseminating across hundreds of kilometers. Newly developed Bayesian phylogenetic methods quantified how SARS-CoV-2 evolution is not only three-times faster in white-tailed deer compared to the rate observed in humans but also driven by different mutational biases and selection pressures. The long-term effect of …

Analysis Of Mitochondrial Dna Sequence Data Demonstrates That Monophyly Of Myotis Occultus Is Complicated By Greater Sampling Of Myotis Lucifugus, Jeffrey M. Lorch, Daniel R. Taylor, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Abstract

The validity of Myotis occultus as a species unique from Myotis lucifugus has been a source of debate. Most recently, many authorities treat M. occultus as a distinct species, at least in part because a previous study showed that M. occultus and M. l. carissima (the subspecies that occurs in closest geographic proximity to M. occultus) form separate monophyletic clades based on sequences of two mitochondrial genes (cytochrome-b [cytb] and cytochrome oxidase subunit II [COII]). We re-evaluated the phylogenetic relationship between M. occultus and M. lucifugus based on mitochondrial sequences …

Unlocking The Mysteries Of Opportunism: Neuroendocrine Insights From An Aseasonal Breeder (Taeniopygia Guttata), Jessica A. Moodie

Graduate Theses and Dissertations (2019 - present)

The regulation of reproductive physiology in animals is mediated by the Hypothalamus-Pituitary-Gonad (HPG) axis. In seasonal breeders, a conserved reciprocal switching of deiodinase enzymes alters thyroid hormone signaling, which controls HPG activity. This study tested the hypothesis that neural regulation of the HPG axis as described in seasonal systems is conserved and repurposed to respond to other cues in aseasonal species. Using water deprivation and nest restriction in the opportunistic Zebra Finch, we were able to create a breeding group and non-breeding group, confirmed by egg laying and changes in ovarian anatomy. Breeding females had clear follicular hierarchy, increased ovary …

Interactions Between Sediment Mechanical Structure And Infaunal Community Structure Following Physical Disturbance, William Cyrus Roger Clemo

Graduate Theses and Dissertations (2019 - present)

Shallow, river-influenced coastal sediments are important for global carbon storage and nutrient cycling and provide a habitat for diverse communities of invertebrates (infauna). Elevated bed shear stress from extreme storms can resuspend, transport, and deposit sediments, disrupting the cohesive structure of muds, and sorting and depositing sand eroded from beaches. These physical disruptions can also resuspend or smother infauna, decreasing abundances and changing community structure. Infaunal activities such as burrowing, tube construction, and feeding can impact sediment structure and stability. However, little is known about how physical disturbance impacts short and long-term sediment habitat suitability and whether disturbance-tolerant infauna influence …

Polluting The Senses: The Impact Of Noise And Light Pollution On Fledgling Movement And Evolution Within The Avian Eye, Margaret C. Mackinlay

Master's Theses

There is more human-generated noise and light today than ever before, a trend tied to ongoing urbanization and with reverberating impacts on a wide range of organisms. While research on these impacts is mounting and particularly plentiful when it comes to birds, there is still much to explore within its effects on avian behavior, fitness, and evolution. In chapter 1, we investigated how fledgling movement is influenced by noise and light pollution. While adult birds have well-documented species-specific responses to these stimuli, fledglings are sorely understudied in this context. We experimentally manipulated light levels and took advantage of an existing …

An Integrative Approach To Managing A Species Of Conservation Concern: Resource Selection, Spatial Ecology, And Population Genetics Of The Green Salamander (Aneides Aeneus), Megan Novak

All Dissertations

The relationship between wildlife and the environment they inhabit is dependent on both spatial and temporal scales. It is therefore crucial that biological investigations account for ecological scale when analyzing patterns and processes established, particularly when such investigations inform conservation management plans. This dissertation provides extensive insight into the conservation biology of the green salamander (Aneides aeneus), a critically imperiled species in South Carolina. The green salamander is a species that exists in a patchy network of rock outcrops within mountainous forest landscapes, and most studies on habitat suitability for green salamanders have been conducted on the macrohabitat, …

Effect Of Plant Genotype On Plant-Microbe Interactions And Multi-Generation Ecosystem Selection Of Microbial Communities Associated With Plant Biomass In Arabidopsis Thaliana, Nachiket Shankar

Graduate Doctoral Dissertations

The microbiome's role in shaping host phenotypes is a critical area of investigation, with implications for ecology, evolution, and host health. Dynamic plant-microbe interactions are influenced by factors like soil type, environment, and genotype. Understanding their impact on microbial communities is key for tailored plant benefits. An artificial ecosystem selection experiment was done for eight generations with Arabidopsis thaliana Ler and Cvi. This revealed distinct microbial communities shaped by genotypes and biomass treatments. Initially, environment dominated, but over time, genotype and biomass gained influence, explaining ~40% of the variation. Moreover, genotype-specific rhizobacterial associations were observed, enhancing understanding of community dynamics …

Specialized Recreation, Spatial Behavior, And Ecological Implications In The Nature Reserve Of Orange County, Ca, Jake Van Deursen

All Graduate Theses and Dissertations, Fall 2023 to Present

A widespread surge in park and protected area (PPA) visitation strikes managers with the imminent challenge of preserving ecological conditions and maintaining accessibility in the open spaces that are a fundamental component to the health and wellness needs of society. In the field of recreation resource management, recreation specialization, the selective channeling of interests and abilities into a specific recreational activity, has contributed to comprehensive understandings of recreation behavior, site preference, management perceptions and conservation support. Contributing to historical understandings of specialization can inform recreation planning on the diversity of uses occurring in urban-proximate PPAs. Survey data providing information on …

Dusky Grouse Population Ecology And Thermal Landscape Ecology In The Great Basin Ecosystem, Stephanie M. Landry

All Graduate Theses and Dissertations, Fall 2023 to Present

Dusky Grouse are a mountainous forest grouse found throughout the western, inland mountain ranges of the United States and Canada. While a few studies have looked at Dusky Grouse in the Rocky Mountain Ecosystem of their range, there have been no prior studies of the Dusky Grouse in the Great Basin Ecosystem aside from a brief survey by Zwickel and Bendell in 2004 in the Duck Creek Range of Nevada. With the available habitats differing in both species diversity and availability on the landscape between the two Ecosystems, I wanted to assess characteristics about the Dusky Grouse populations at the …

Restoration Strategies For Wetlands In The Arid West: Seeding And Planting Approaches For Lakeshore Ecosystems, Jes Braun

All Graduate Theses and Dissertations, Fall 2023 to Present

Wetlands are widely recognized for their valuable benefits such as providing habitat, improving water quality, and reducing the impacts of flooding. However, wetlands face threats from development, drought, and invasive species. This is particularly apparent in the arid west, where upstream water use and drought make water scarcer and contribute to dramatically changing water levels. Here, I investigated revegetation techniques for lakeshore wetlands, using Utah Lake as a case study. Although recent management efforts have minimized invasive Phragmites cover, the desired plant communities are not returning as quickly as needed, highlighting the need to research restoration techniques. Through my research, …

Reducing Inputs And Adding Value To Turfgrass Systems Through Clover Inclusion And Plant Growth-Promoting Rhizobacteria Applications, Paige E. Boyle

All Graduate Theses and Dissertations, Fall 2023 to Present

Recently, the US has seen an expansion in the amount of turfgrass land cover (lawns, parks, roadsides, sports fields, and golf courses), as well as an interest in reducing fertilizer, water, and pesticide use in these grass systems. To help maintain quality and function while reducing resource inputs, two promising approaches have emerged: planting clover into lawns and applying plant growth-promoting rhizobacteria.

White clover and grass mixtures have been studied for their ability to cut down on fertilizer usage and provide a uniform, dark green lawn, but other clover types have not been as widely studied and may provide similar …

Ecology And Management Of Dyer's Woad (Isatis Tinctoria) In Northern Utah, Erin Marie Hettinger

All Graduate Theses and Dissertations, Fall 2023 to Present

Dyer’s woad (Isatis tinctoria L.) is a non-native forb that continues to threaten natural areas throughout Northern Utah and much of the Intermountain West. Once introduced, dyer’s woad can become extremely invasive, decreasing forage quality, and displacing native species. While dyer’s woad is found throughout much of Northern Utah, its range in other states remains limited. If promptly managed, control success in these areas will be much higher and populations may be kept at bay before ecological damage becomes severe.

This project tested the ability of dyer’s woad seedlings to compete with common rangeland grasslands at varied densities as …

Activity Patterns Of Whiptail Lizards (Aspidoscelis) Found In The Northern Chihuahuan Desert, Guillermo Alvarez

Open Access Theses & Dissertations

Traditional lizard pitfall traps were modified to allow organisms to escape, while collecting valuable ecological data. Modified camera traps were capable of detecting the same species as traditional traps in a semi-arid environment, without posing the associated mortality risks. Pitfall-camera traps were used to sample the activity of the Side-blotched Lizard (Uta stansburiana) and the Southwestern Fence Lizard (Sceloporus cowlesi) in an urban wetland during four continuous years. Evaluations on activity pattern and the activity overlap between the two species revealed extensive overlap, with minor but significant seasonal shifts mediating coexistence. Traps were also effective at detecting other reptiles, invertebrates, …

Developing Next-Generation Ecoinformatics Tools For Advancing Global Change Science, Ifeanyi H. Nwigboji

Open Access Theses & Dissertations

Ecosystems are responding to a variety of human-induced, interlinked stressors that have emerged from changing climate, alteration to the global water cycle, sea-level rise, and land use and land cover change, among others. Quantifying these changes and their associated impacts on ecosystems requires a huge amount of long-term data. Due to advances in data collection techniques, such as remote sensing platforms, environmental sensors, synthesized datasets, and various software technologies, the volume and variety of long-term ecological data being collected has tremendously increased. Although there are several complex models and analyses that are increasingly parametrized with data from such sensors, there …

Lizard Communities In A Shifting Landscape: The Current State Of Insectivorous Lizard Communities In The Jornada Basin Between Grassland, Mesquite Dune, And Creosote Bush Habitats In A Semi-Arid Landscape Undergoing Shrubification, Julie Marie Schlichte

Open Access Theses & Dissertations

Lizard communities in arid lands can act as model systems of how diversity and abundance are impacted in the face of ongoing climate variability and change, as they are sensitive to shifts in precipitation, temperature, and changing vegetation structure. The main research question we hope to answer is how the community composition of lizards varies between dominant vegetation types (Mesquite dunes, grasslands, and Creosote Bush flats). Nine sites (3 of each dominant vegetation type) with 16 pitfall traps each (n = 144) were surveyed from June 2016 -- June 2017. 12 lizard species were captured, consisting of 923 total captures …

Evolution Of Forest Bitis (Macrocerastes) In Africa: Phylogeography, Population Genetics, And Potential As A Model For Batesian Mimicry, Eugene Richard Vaughan

Open Access Theses & Dissertations

The major biogeographical patterns characterizing the diversification of widely distributed species in the African rainforest remain poorly understood because of the low number of well-sampled studies that are focused on this region. I examine the phylogeography and population genetics of two broadly sympatric sister lineages of large African forest vipers (genus Bitis, subgenus Macrocerastes), the rhinoceros viper (B. nasicornis) and the Gaboon vipers (B. gabonica and B. rhinoceros). Despite their close relationship, these two lineages have notably different patterns of divergence in time and space. A time-calibrated phylogeny with sequence data from five genes, and population structure and PCA analyses …

Patterns In Winter Stonefly Distribution Along A River Continuum And Land-Use Gradient In Northwest Arkansas Streams, Zachary Tipton

Graduate Theses and Dissertations

Freshwater ecosystems are facing a crisis with extinction rates of aquatic species exceeding those of their terrestrial counterparts by up to fivefold. This decline is predominantly attributed to evolving land use patterns within watersheds, leading to chemical and physical transformations in freshwater habitats. Northwest Arkansas (NWA) represents one of the fastest-growing regions in the United States, undergoing substantial shifts in land use. Consequently, the status of aquatic life in this region remains uncertain. Addressing this concern, the latest Arkansas Wildlife Action Plan emphasizes the necessity of distribution and population data to guide conservation efforts for Species of Greatest Conservation Need …