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Analyzing Ballast Water Treatments, Invasive Species, And Pathogens, And A Decade-Long Analysis On The San Francisco And Baltimore Ports, Jasmin Ibarra-Cortes

Master's Projects and Capstones

Installation of advanced technologies to treat ballast water on ships is necessary to meet current ballast water management standards and reduce the secondary spread of invasive species during intracoastal voyages. This research includes a literature review on non-native aquatic species, particularly diapausing eggs, and available treatment methods for installation. A comparative analysis from 2014 - 2024 on bulker, tanker, and container vessels arriving coastwise to the ports of San Francisco and Baltimore was performed to evaluate treatment installation trends, traffic patterns, and the effectiveness of treatment(s) on targeting diapausing eggs. Use of ultraviolet (UV) radiation combined with filtration has increased …

Plastic In The Pack: Assessing Microplastic Risk To Urban Coyotes (Canis Latrans) In The San Francisco Bay Area, Elaina E. Herrmann

Master's Projects and Capstones

Microplastics are an emerging concern worldwide. However, their impact on terrestrial mammals, such as Canis latrans (coyotes), has yet to be extensively studied. Coyotes are unique in their ability to adapt to urban environments and have recently begun bridging the gap between marine and terrestrial food webs. This research examines the potential sources and impact of microplastic exposure in urban coyotes in the San Francisco Bay Area and possible food web impacts through literature synthesis and Geographic Information System (GIS) mapping. This research examined potential mechanisms for direct and trophic microplastic uptake by coyotes resulting from the anthropogenic, terrestrial, and …

Balancing Burrowing Owl (Athene Cunicularia Hypugaea) Protections While Maintaining Renewable Energy Development Within The San Joaquin Valley, Madison Lenzi Mcginn

Master's Projects and Capstones

Balancing the needs of wildlife and people has long been a complex challenge. The San Joaquin Valley exemplifies this tension, as space for agriculture and urbanization compete for land use of native grasslands– often resulting in the conversion of grasslands for agriculture fields, commercialized areas, or energy development. With an increasing number of agricultural landscapes going fallow and the passing of SB-100 in 2018, solar farm development has emerged as an attractive option to offset financial losses from unproductive farmland. However, the same landscapes favored for solar development also provide suitable habitat for sensitive species such the western burrowing owl …

Turtle Creek Tree Restoration Project, Rebecca Beneroff, Risa Kanefsky, Max Dicerbo, Pj Newhart, Amanda Mitchell

Final Reports in ENST 411: Environmental Community Projects

Over the course of this project our group members Rebecca, Max, PJ, Amanda, and Risa worked closely with Jim Knight and Brian Auman from Turtle Creek Park to help research, plan, and execute a tree transplanting event that would be efficiently implemented and environmentally sound. This work involved extensive preparatory work in the park including soil testing, bare leaf tree identification, tree and shrub species characterization, and recommendation. The entire process was rooted in the most up to date literature and scientific practices surrounding bare root tree nurseries, existing land management plans, invasive species and public park management, ecological succession, …

Microbial Biodiversity Of The James River Rock Pool Ecosystem., Jordan C. Heydt

Masters Theses, 2020-current

Rock pools are ephemeral aquatic environments that offer a unique opportunity to study complex communities and their responses to environmental changes. The urban James River rock pool system consists of over 700 individual rock pools varying in size and depth. This unique urban freshwater ecosystem has been studied for its invertebrate, plant, and zooplankton populations but not for its microbial community composition. To fill that gap, the microbial community of this system was characterized using 16S rRNA gene sequencing, and the influence of environmental variables on the community composition was analyzed. Our findings show variation in microbial community composition across …

Experimentally Testing A Mechanism Of Urban Adaptation: Are Wild Catbirds Able To Immediately Adjust Their Song In Response To Urban Noise?, Eriberto Osorio

Masters Theses, 2020-current

Anthropogenic noise is loud and low-frequency (low-pitch) sound with frequencies spanning from 1-2.5 kHz in frequency. In noisy urban areas, many birds sing songs with higher minimum frequencies, which can avoid the masking effects of anthropogenic noise. However, the mechanism for an individual to alter spectral aspects of bird song in real time to avoid the masking effect of urban noise is unknown. Immediate flexibility is the ability a bird may use to shifts their song frequency or amplitude in response to noise fluctuations in the environment. Some species that sing higher frequency songs in noisy habitats are not able …

Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xxxviii. Parabuthus Puntlandus Sp. N. From Somalia (Puntland) (Buthidae), František Kovařík, František Šťáhlavský, Hassan Sh A. Elmi, Roman Štarha

Euscorpius

A new species Parabuthus puntlandus sp. n. from Somalia (Puntland) is described. Combination of five characters; metasoma V black; pectine teeth number 39–42 in both sexes; pedipalp chela length/width ratio 3.05–4.26 in both sexes; metasoma and telson sparsely hirsute; smooth inner side of the base of fingers of pedipalp chela (tubercle absent) distinguish P. puntlandus sp. n. from all other species in the region. In addition to the analyses of external morphology, we have provided descriptions of the karyotype of P. puntlandus sp. n. (2n=16). Included is also a map of distribution of Parabuthus species in Horn of Africa.

Temporal Assessment Of Fish Communities In A South Central Plains Ecoregion Watershed, Tara L. Schnelting

ATU Theses and Dissertations 2021 - Present

Among South Central Plains ecoregion fish communities, there is limited knowledge of the importance of headwaters yet this information is needed to understand their role in fish communities. I addressed this gap by assessing seasonal changes in fish communities in headwater streams of the Moro Creek watershed, Arkansas. I conducted two studies pertaining to temporal fish community assessments: (i) utilize multi-season, community occupancy models to estimate μ (species probability), Ω (community occupancy mean), and p (detection probability) and (ii) utilize beta diversity (β) analyses to address the diversity across different scales in the headwaters of the Moro Creek …

Assisted Reproductive Technologies For Southern Cricket Frogs (Acris Gryllus), Audrey Grace Koltz

Honors Theses

Amphibians are facing the most drastic biodiversity declines of all vertebrates, with an estimated 41% of amphibians threatened with extinction. Captive breeding programs employ a variety of assisted reproductive technologies including environmental manipulation, hormonal therapies, artificial fertilization, and gamete preservation to augment vulnerable populations and optimize genetic diversity. Amphibians require a species-specific combination of environmental, social, and physiological cues to reproduce, which makes universal and successful captive breeding programs especially elusive. Here, I investigate assisted reproductive technologies for a small frog species, the southern cricket frog (Acris gryllus). Establishing successful methods for southern cricket frogs may yield promising results for …

Impact Of Unconventional Gas Extraction On Tributaries Of Tenmile Creek, Greene County, Pennsylvania: A 12-Year Perspective, Christian L. Beall

Electronic Theses and Dissertations

Much of southwestern Pennsylvania has been central to a rapid increase in development for unconventional natural gas extraction in the past two decades. The continued monitoring of streams over their lifetime as extraction sites is pivotal to understanding the effects of fracking on local waterways and their ability to provide for wildlife and human use. Here, using multiple indices of biotic integrity (IBI), I perform analyses of fish and macroinvertebrate communities as well as water chemistry on two streams, Bates Fork (with shale wells) and Fonner Run (without), as part of a follow-up to work performed there from 2010-2012. Fish …

Demography Of Alligator Snapping Turtles (Macrochelys Temminckii) Along A Fishing Pressure Gradient, Luke T. Micek

Electronic Theses and Dissertations

Passive fishing gear is a threat to the alligator snapping turtle (Macrochelys temminckii). The spatio-temporal persistence of this threat and its impacts on M. temminckii populations has not been quantified. I quantified the density of passive fishing gear and the demographic parameters of M. temminckii along a fishing pressure gradient in East Texas streams. Most gear was abandoned and illegally deployed, with densities varying seasonally. Detectability of passive fishing gear declined with increasing gear age, water depth, and volume, but increased with increasing precipitation. Macrochelys temminckii catch per unit effort, abundance, and survival was lower at sites with …

Genomic Structure Among Populations Of A Regionally Rare Perennial Plant Indicates The Need For Reevaluation Of Management Units, Cheyenne Moore, Angela J. Mcdonnell, Scott Schuette, Christopher T. Martine

Faculty Journal Articles

Conservation of rare species often relies on the delineation of management units and genomic tools can now be applied for this purpose. However, this is not as common on a local scale, where populations are often small and fragmented, despite the utility of informing conservation and management practice at the regional level. We use a genotyping by sequencing (GBS) approach to assess the perennial riparian plant species Baptisia australis (Fabaceae) in Pennsylvania, where the taxon is at the edge of its natural distribution and considered threatened. In this system, we investigate whether sampled subpopulations exhibit genetic structure. We find that …

Large Mammal Herbivores As Gardeners Of Tropical Forest Ecosystems, Kathryn Garner

Student Scholarship

Ecosystems worldwide are experiencing changes in structure and function as populations of fauna decline and experience local extinctions (Torres-Romero et al. 2020). Due primarily to their body size, large mammal herbivores (LMHs) are disproportionately prone to extinction from human activities such as agricultural expansion, deforestation, and anthropogenic climate change (Pringle et al. 2023). Additionally, as the number of domesticated LMHs (i.e. cattle, pigs, etc.) continue to increase in both density and distribution, their wild counterparts are continually displaced, resulting in increased competition for resources and an increased risk of disease transmission between domestic to wild species (Pringle et al. 2023; …

Ghosts In Glass: Ghost Crabs (Ocypode Quadrata) As Judges Of Glass Sand For Coastal Restoration, Emily Parrish

Poster Presentations

Coastal erosion is heavily impacting coastal ecosystems across the Gulf. For instance, the state of Louisiana loses a football field worth of land every 100 minutes (Couvillion, 2017). The drastic loss of coastline highlights the dire need for restoration in the Northern Gulf Coast. An unexpected solution to this sediment loss may solve two major environmental issues at once by diverting millions of tons of glass waste from entering America’s landfills each year. By crushing glass to create sand and gravel for coastal restoration, we may generate a consistent and sustainable source of substrate. Our goal is to determine the …

The Impact Of Maternal Age On The Expression Of Transgenerational Plasticity In Daphnia Pulicaria, Calvin Nguyen

2025 Spring Honors Capstone Projects - Archive

Transgenerational plasticity refers to heritable, non-genetic changes in phenotype that persist across multiple generations and can enhance offspring survivability in variable environments. In Daphnia, increasing maternal age has been associated with maladaptive plasticity. To investigate this relationship, six clones were collected from two Wisconsin lakes and acclimated to laboratory conditions through a common garden rearing process. For each clone, ten replicates were generated and evenly divided between young (clutches 2–4) and old (clutches 5–8) maternal age groups. Offspring were exposed to three dietary treatments for three experimental generations: one fed only green algae, one fed only cyanobacteria (a nutritionally …

Elucidating The Role Of Transposable Element Derived Gene, Dplg3, In Drosophila Melanogaster, Kaisy A. Martinez

2025 Spring Honors Capstone Projects - Archive

A big fraction of most eukaryotic genomes is comprised of transposable elements (TEs). TEs are mobile genetic sequences often causing deleterious effects as they increase in copy number. On rare occasions, TEs can undergo molecular domestication, where the TE proteins are co-opted by the host to serve cellular functions. In Drosophila melanogaster, domestication from PIF/Harbinger TEs has resulted in five Drosophila PIF-Like Genes (DPLG1-4 and 8). This study focuses on investigating the function of DPLG3. In DPLG3 knock out lines, DPLG3-KO, a fraction of the progeny shows an abnormal gonad phenotype. We sought to confirm …

Uncovering The Evolutionary Origins Of Neo-Sex Chromosomes In The Insect Family Membracidae, Mary Kumah

2025 Spring Honors Capstone Projects - Archive

This research explores the evolution of the neo-XX/XY sex chromosome system of Amblyophallus exaltatus, a treehopper insect in the family Membracidae. Neo-XX/XY sex chromosome systems can evolve from an XX/X0 sex chromosome system via fusion events between the X chromosome and an autosome. Although cytological work has indicated the presence of a neo-XX/XY system within A.exaltatus, the chromosomal identity of the fused autosome and the molecular drivers behind this chromosomal fusion remain poorly understood. By performing a coverage analysis with whole genome sequence data, the parts of the A.exaltatus genome that fused with the X chromosome will be better …

The Movement Ecology, Ranging Patterns, And Territoriality Of Azara’S Owl Monkeys (Aotus Azarae) In The Argentinean Chaco Forest, Jeremy D. Pustilnik

Master of Environmental Science Theses

Azara’s owl monkeys (Aotus azarae) are small, pair-living, socially monogamous primates that inhabit the Chaco Forest of South America. Their activity and life history patterns have been particularly well studied, however, their movement ecology and ranging patterns within their home ranges remains largely unknown. Herein I descriptively analyze these patterns with respect to time, space, ambient environment, and physical environment using spatial information on five owl monkey groups that were followed over the course of a year between 1998 and 1999 at a multi-decade-operating field site near Formosa, Argentina. Analysis of distance and speed moved during different diel …

A Tale Of Two Asters: Resolving The Plant And Microbial Community Structure Of An Invasive And Native Forb, William Cartelli

Theses, Dissertations and Culminating Projects

Old fields dominated by flowering forbs are frequent targets for ecological restoration, particularly because they are often inhabited by invasive species whose ecological effects remain context dependent and widely debated. While native plants are typically favored in restoration efforts, and invasive species viewed as threats to biodiversity, such classifications may oversimplify ecological function. This study investigates two dominant genera of the Asteraceae family —Centaurea stoebe (L) (non-native) and Solidago spp. (S. rugosa and S. canadensis, both native)—to examine whether biogeographic origin or ecological strategy more strongly influences their impact on above and below ground community structure. Despite their contrasting origins, …

Movement Ecology Of Sandhills Chub, A Carolina Endemic, Zachary Adam Ramsey

Electronic Theses and Dissertations

Fish movement studies have traditionally focused on species that support commercial and recreational fisheries, but recently more focus has been given to non-game, stream fishes because of their recognized importance in maintaining biodiversity within these ecosystems. Stream fish movement is described as being “restricted” and following a leptokurtic distribution via diffusive spread related to environmental and biological factors. Many studies of stream fish movement ecology in North America have occurred in high-gradient streams with coarse substrate in mountains or in streams of the interior plains. Sandhills streams of the southeastern USA are characterized as warm-water, low gradient, and dominated by …

Modifying The Comb, Rethinking The Install: Integrated Approaches To Honey Bee Colony Establishment And Winter Survival, Shelby A. Kittle

Department of Entomology: Dissertations, Theses, and Student Research

The European, or Western honey bee (Apis mellifera L.) plays a vital role in global ecosystems and agriculture, providing essential pollination services and producing valuable hive products. However, honey bee colony losses have escalated worldwide, but particularly across the United States due to various stressors, including biotic and abiotic factors, mismanagement, and environmental challenges. This thesis investigates key challenges in honey bee management and explores solutions aimed at improving colony health and productivity.

Chapter 1 provides an overview of the beekeeping industry, detailing its economic importance, services, and products, as well as the many challenges faced by beekeepers. It …

Epidemiological Inferences Of The Impacts Of Winter Ticks On Moose Health, Krishna S. Woerheide

Department of Entomology: Dissertations, Theses, and Student Research

The North American Moose (mooz in Anishinaabemowin, Ojibwe language, Alces alces), a culturally significant subsistence species for the Anishinaabe people, faces population decline due to calf predation, pathogen transmission, and parasitism by the winter tick (Dermacentor albipictus), all exacerbated by climate change. This study explores the impact of winter tick infestations on moose health, with a focus on natural mineral seeps as potential transmission hotspots in moose habitats within the Grand Portage Indian Reservation (Gichi Onigaming), on Isle Royale National Park (Minong), and within the 1854 Ceded Territory (greater northeastern Minnesota) - ancestral and present homelands of …

Ediacaran Paleocommunity Structure, Body Size Evolution, And The Rise Of Complex Animals, Matthew Philip Craffey

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The Ediacaran period (635-538ma) is a key interval in the evolution of life as it records the first macroscopic animal communities. Major extinction pulses appear to have altered the composition of the global marine biosphere between each sub-interval of the Ediacaran Period: the Avalon, White Sea, and Nama assemblage Zones. While considerable attention has been paid to the causes of these extinction pulses, less has been afforded to the consequences of Ediacaran biotic turnover for community organization and function. Moreover, it is unclear how body size - the defining trait of macrofauna - affected the transition between animal groups across …

Influence Of Biotic And Abiotic Factors On Decomposition And The Determination Of Time Since Death: Applications Of Forensic Entomology And Taphonomy, John Oladapo Obafunwa

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The determination of the postmortem interval (PMI) is essential for the investigation and successful prosecution of suspected cases of homicide. While the forensic pathologist might be able to draw fairly accurate conclusions during the initial 24–36 hours, beyond this period, the assistance of other experts like forensic entomologists and taphonomists would be required. The present study was designed to observe the postmortem changes in Sus scrofa placed in a cage in Nebraska, located in the American Central Great Plains. The setting is in an open grassland in late spring to early summer. The observed variables with respect to biotic and …

Spatial Ecology And Predator–Prey Interactions Of Mountain Lions In California's San Francisco North Bay, Jacob A. Harvey

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

Understanding spatial ecology and predator-prey interactions are central to wildlife ecology and conservation. We tracked mountain lions with GPS telemetry to evaluate space use, predator-prey interactions, and resource selection in California’s San Francisco North Bay, USA. In Chapter 1, we evaluated the influence of human disturbance on home range size, prey composition, and kill rates on black-tailed deer (Odocoileus hemionus columbianus) across an urban-rural gradient. Both males and females increased home range size with increasing development at low to moderate levels of development, but female home range size stabilized across greater proportions of development while male home range …

Maggot Mass Effect On The Development And Survival Of Forensic Blow Flies, Akomavo Fabrice Gbenonsi

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

Forensic entomology scientists use blow flies' developing patterns to estimate the postmortem interval (PMI). However, larval aggregations produce metabolic heat, resulting in complex microclimates that may change growth timetables. This study investigates how larval density and associated temperature changes affect the development and survival of two forensically essential blow fly species, Lucilia sericata and Calliphora vicina.

This study examined how larval density and associated thermal profiles affect the development of both blow fly species. Using a split-plot design, we tested four larval densities at 25°C and 30°C, with temperature gradients measured via thermocouple at four mass positions three times …

Morphology Of Smallmouth Bass (Micropterus Dolomieu) In Arkansas, Robert Laroche

Biological Sciences Undergraduate Honors Theses

The Smallmouth Bass, Micropterus dolomieu, is one of the most important game fishes in Arkansas. Three distinct lineages are recognized from different river basins: the Northern, Neosho, and Ouachita Smallmouth Bass. Understanding the biodiversity within this species complex inhabiting different water bodies in Arkansas is important for effective management of the fisheries resource and to guide conservation efforts. But current data on distribution of distinct forms are insufficient to guide management. The primary goals of the study presented here was to quantify morphological characteristics to identify distinct lineages of Smallmouth Bass, and to determine their specific locations within Arkansas streams …

Assessment Of Lake Salvador Shoreline Dynamics To Support Restoration Of Submerged Aquatic Vegetation In Jean Lafitte National Historical Park And Preserve, Louisiana, Lydia V. Dipaola

LSU New Orleans Theses and Dissertations

High wave energy degrades shoreline habitat between Lake Salvador and Jean Lafitte National Historical Park and Preserve (JELA), Louisiana. JELA constructed a northern breakwater in 2004, and a southern breakwater in 2024 to protect the shoreline and promote restoration of submerged aquatic vegetation (SAV). This study analyzes Sentinel-2 imagery to quantify coastal loss along the JELA-Lake Salvador using the Change Polygon Approach, assessing annual, cumulative and major storm event-associated shoreline changes for January 2017-2025. SAV cover, nekton diversity, wave energy, and turbidity were measured before-and-after southern breakwater construction to monitor ecological and environmental outcomes. The JELA-Lake Salvador shoreline has lost …

Potamogeton Crispus Invasion: Impacts On Native Aquatic Plants And Associated Faunal Habitat, Meghan-Grace Slocombe

All Graduate Theses and Dissertations, Fall 2023 to Present

Aquatic invasive plants are non-native plants that invade a water body and displace native aquatic plants. Invasion depletes the native plant community's ability to provide ecosystem services, including improved water quality, decreased problematic algae, and increased animal habitat. The loss of these ecosystem services reduces the value of fishing, boating, and swimming opportunities in aquatic ecosystems. The potential changes in plant communities and services are particularly important at sites targeted for restoration because project goals typically include increasing ecosystem services, including wildlife habitat. Curly-leaf pondweed (Potamogeton crispus L.) is a problematic invasive species in North America. To better manage …

Ghosts In Glass: Ghost Crabs As Judges Of Glass Sand For Coastal Restoration, Emily Parrish

Honors Theses

Over 60% of the Gulf of Mexico coastline is actively eroding, which has resulted in thousands of miles of lost coastline over the last 100 years. This drastic loss of coastal land highlights the dire need for coastal restoration across the entirety of the Gulf Coast. A vital aspect of restoring these eroded areas is replenishing eroded substrate, traditionally conducted through offshore dredging of substrates which comes with high economic and ecological costs. Recycled glass sand may be able to fill this role and reduce our reliance on dredging while lowering the amount of glass waste entering landfills each year. …