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Lead Biosorption By Oceanobacillus Profundus Kbz 3-2: Strategies For Bioremediation Systems In Kabwe, Danielle S. Desmarteau Jan 2026

Lead Biosorption By Oceanobacillus Profundus Kbz 3-2: Strategies For Bioremediation Systems In Kabwe, Danielle S. Desmarteau

Scripps Senior Theses

Lead contamination remains a significant global public health concern, particularly in Kabwe, Zambia, the site of a former lead mining operation. Bioremediation, which utilizes biological materials and processes to remove environmental contaminants, represents a promising approach for addressing lead pollution. However, the development of effective bioremediation systems requires a detailed understanding of the mechanisms underlying metal removal and the feasibility of implementation in low-resource settings. Oceanobacillus profundus KBZ 3-2, a bacterium isolated from Kabwe mine waste, has demonstrated the ability to remove lead from aqueous environments. This study proposes to investigate the mechanism of lead biosorption by this organism, …


Food Stamp Participation And Health Outcomes In Ca Immigrants, Esther Kang Jan 2026

Food Stamp Participation And Health Outcomes In Ca Immigrants, Esther Kang

Scripps Senior Theses

The U.S. social welfare system includes programs aiming to increase access to nutritious food to reduce nutrition insecurity. However, studies suggest that immigrants continue to face disproportionate risks of nutrition insecurity and may face barriers to enrollment due to legal status. This study, using secondary data from the 2023 California Health Interview Survey, examines the associations between food stamp participation, food insecurity, and clinical diagnosis of diabetes among adult U.S.-born, naturalized, and non-citizen adults in California. The findings suggest that those enrolled in food stamps are more likely to report food insecurity than those who are not enrolled, and that …


Advancing Nanotechnology For Hematological And Osteological Disorders, Chase K. Hamilton Jan 2026

Advancing Nanotechnology For Hematological And Osteological Disorders, Chase K. Hamilton

Integrated Studies

When people think of medicine, they often picture stethoscopes, routine clinical checkups, surgeries, and standard prescriptions. One field that needs more acknowledgement is the technological side. As technology continues to evolve, healthcare advances alongside it, with nanotechnology emerging as a substantial area of innovation. This paper reflects the expanding role of nanotechnology in modern medicine, focusing on its potential applications in trauma and internal medicine care and in the treatment of blood and bone disorders as well as bone and blood related cancers. By working at an extremely small scale, nanotechnology allows for more precise and targeted treatment, reducing damage …


Public Libraries: Communities Need Them To Survive, Genesis Wilson Jan 2026

Public Libraries: Communities Need Them To Survive, Genesis Wilson

Integrated Studies

Public libraries continue to play a highly impactful and transformative role in community life, even as digital technologies reshape how individuals access information, participate in civic life, and access social support. The literature consistently shows that public libraries function not only as information centers but also as inclusive community anchors that advance digital equity, civic engagement, lifelong learning, and social well-being. Drawing on research from respected scholars such as Akst, Alemanne et al., Lewis, Elmborg, and Schencker, this literature review integrates key themes related to public libraries as community builders, technology and broadband leaders, and essential social support systems for …


Forage Legume Community Dynamics In Response To Stand Management, Nicholas Warren Jan 2026

Forage Legume Community Dynamics In Response To Stand Management, Nicholas Warren

Doctoral Dissertations

A primary challenge for perennial forage production systems is maintaining crop productivity and forage quality over time. Including legume species in these systems is an opportunity to reduce external inputs, to extend the seasonal productivity of a pasture, and to balance the nutritional characteristics of grass species. However, legume persistence in mixed stands is frequently poor. Identifying harvest practices, legume species, or species mixtures that improve legume persistence would help to maximize the ecosystem services of forages. I conducted a four-year field experiment (2019 to 2022) in southeastern New Hampshire to evaluate the productivity and persistence of four perennial legumes …


Perception Of Posed And Naturally Occurring Emotion Expressions In Close Friendships, Kaitlyn M. Mcmullen Jan 2026

Perception Of Posed And Naturally Occurring Emotion Expressions In Close Friendships, Kaitlyn M. Mcmullen

Doctoral Dissertations

While relationships are critical to our daily emotional lives, the limited research on emotion perception among close friends presents inconsistent evidence concerning whether differences exist between close friends and strangers. The present work examined the ways in which familiarity between close friends’ shapes emotion perception. In Study 1a, expressors provided both naturally occurring and dynamic posed emotion expressions for seven emotion categories (anger, sadness, fear, disgust, happiness, surprise, and neutral) in order to develop a stimulus set where the stereotypicality of the expressions varies within-subjects. In Study 1b, a self-identified close friend of each expressor viewed and rated the expressions …


The Garden Of The Machine: Simulated Wildness And Digital Domestication In American Literature 1970-2020, Cameron Netland Jan 2026

The Garden Of The Machine: Simulated Wildness And Digital Domestication In American Literature 1970-2020, Cameron Netland

Doctoral Dissertations

Studying American literature produced during the Information Age, from 1970 to 2020, reveals an evolution of wild human resistance to the increasing powers of digital technology. These increasing powers include capturing attention, fostering dependence, and training behavior through a process I call digital domestication. Digital domestication distances people from wildness, and as William Cronon writes in “The Trouble with Wilderness”, “Learning to honor the wild—learning to remember and acknowledge the autonomy of the other—means striving for critical self-consciousness in all of our actions.” (20). Through this framework of wildness, one reads characters in fictional narratives resisting non-coercive new technologies as …


Launching Love Online: How Soft-, Hard-, And No-Launch Practices Shape Perceptions Of Commitment And Relationship Security, Aleana Goetz Jan 2026

Launching Love Online: How Soft-, Hard-, And No-Launch Practices Shape Perceptions Of Commitment And Relationship Security, Aleana Goetz

Master’s Theses

Social media has introduced new ways couples signal relationship status, ranging from a “hard launch” (a clear couple post) to a “soft launch” (subtle cues such as hands or hints) to a “no launch” (no posting at all). Although these posting choices may seem minor, they may shape how committed and secure a relationship feels. Guided by the Investment Model (Rusbult, 1980) and interdependence theory (Kelley & Thibaut, 1978), the present study examines whether relationship visibility on Instagram relates to perceived partner commitment and relationship security.

A total of 176 participants (36 male, 118 female, 22 did not report) viewed …


Mitochondrial Efficiency: Bridging Early-Life Environment And Organismal Performance, Kayla E. Lichtner Jan 2026

Mitochondrial Efficiency: Bridging Early-Life Environment And Organismal Performance, Kayla E. Lichtner

Master’s Theses

Mitochondria operate at the forefront of organismal-environmental interactions. Despite remarkable diversity in mitochondrial function both within and among species, all mitochondria serve a universal role in facilitating the flow of energy between organisms and their environment. Energetic efficiency, the way in which organisms assimilate and transform environmental substrate into physiological currency, is a major determinant of organismal performance. Although previous studies have shown that early-life environment can have lasting effects on metabolism, the underlying mechanisms driving the emergence of mitochondrial phenotypic variation remain poorly understood. Leach’s storm-petrels (Hydrobates leucorhous) provide a valuable opportunity to investigate longitudinal hypotheses of …


Overview And Methods Of Molecular Paleontology: A Review, Shelby Touchstone Jan 2026

Overview And Methods Of Molecular Paleontology: A Review, Shelby Touchstone

Williams Honors College, Honors Research Projects

Molecular paleontology—the study of ancient biomolecules preserved in fossils and sediments, including ancient DNA, lipids, and proteins—has motivated researchers since the 1950s, inspiring both scientific inquiry and broader cultural imagination. Think Jurassic Park. This honors thesis presents a comprehensive review of the history, current state, and methods of the field of molecular paleontology. Drawing on peer-reviewed literature and scholarly resources accessed through databases such as EBSCO and Bierce library, this review examines key techniques such as Next Generation Sequencing and amino acid racemization and will go over limitations and controversies in the field. It will also explore potential new …


Rebuilt From The Same Stone: Religion And Colonization In Sixteenth-Century Mexico, Aziren South Jan 2026

Rebuilt From The Same Stone: Religion And Colonization In Sixteenth-Century Mexico, Aziren South

Williams Honors College, Honors Research Projects

When the Spanish landed in what is now Mexico in the early sixteenth-century, religious figures on mission trips took it upon themselves to convert indigenous peoples to Christianity and to the European way of life. The role of these missionaries was complex. They wanted to abolish the way of life of the societies they encountered, but they were also some of the most prominent defenders of the people they were trying to convert. They lived with them, learned their languages, advocated for their protection, and some supported indigenous efforts to preserve their history in writing. Ultimately, this paper aims to …


Rate Response Of Curlyleaf Pondweed And Native Plants To Flumioxazin In Minnesota Lakes, Pearl J. Jensen Jan 2026

Rate Response Of Curlyleaf Pondweed And Native Plants To Flumioxazin In Minnesota Lakes, Pearl J. Jensen

All Graduate Theses, Dissertations, and Other Capstone Projects

Curlyleaf pondweed (Potamogeton crispus L.) is an invasive aquatic plant present across the United States that causes significant recreational issues, outcompetes native plant species, and depletes water quality. Before senescing in mid-summer, curlyleaf pondweed forms a large number of turions that can lay dormant in the sediment for several years. Typical herbicide management of this species occurs in early spring to target the plant before turion production occurs and while native plants are dormant. Flumioxazin has shown potential in curlyleaf pondweed management in small scale studies, but its effects have not been assessed in operational management. In this study, treatments …


Ethanol And Iron Absorption Interactions Within Crayfish Invertebrate Models, James Rollman, Andrew Wissmar Jan 2026

Ethanol And Iron Absorption Interactions Within Crayfish Invertebrate Models, James Rollman, Andrew Wissmar

Williams Honors College, Honors Research Projects

Analysis of the effects of alcohol consumption (ethyl-alcohol) on iron absorption within crayfish model. The use of tube-feeding provides a novel, more precise output, and less invasive procedure compared to the traditional approach of dissolving the target substance in tank water and measuring hemolymph changes. The project aims to determine the extent to which alcohol influences iron absorption. Ultimately, the choice of iron reflect the future potential to aid in research with genetic hemochromatosis and or Iron overload.


Galician Culture Through The Lens Of Sargadelos, Rosella J. Messaros Jan 2026

Galician Culture Through The Lens Of Sargadelos, Rosella J. Messaros

Williams Honors College, Honors Research Projects

This research project covers the history and significance of the Sargadelos ceramics brand in Galicia, Spain. I then relate my research to my own personal experiences, tying into my family's Spanish heritage.


Ceramics And Trade In Mesoamerica: Identity And Resistance In The Maya Culture, Mason A. Swanson Jan 2026

Ceramics And Trade In Mesoamerica: Identity And Resistance In The Maya Culture, Mason A. Swanson

Williams Honors College, Honors Research Projects

The region of Mesoamerica has been researched extensively by archaeologists over the past decades. There are numerous cultures and civilizations that occupied Mesoamerica over thousands of years. This paper will focus on the Maya, one of the most researched and examined of the cultures of Mesoamerica. By examining the ceramics and trade of the Maya one can reconstruct how the Maya identity was viewed in the past. Often the Maya are suggested to have experienced a collapse at the end of the Classic period around (AD 900). This, however, is an oversimplification of the events that occurred. The goal of …


The Implementation Of A Token Economy On The Behaviors Of Children With Adhd, Dominic M. Hritsko Jan 2026

The Implementation Of A Token Economy On The Behaviors Of Children With Adhd, Dominic M. Hritsko

Williams Honors College, Honors Research Projects

The Saturday Treatment Program (SatTP) is a ten-day treatment program that was designed through the Cleveland Clinic and takes place at a middle school on Saturdays during the school year. The program design follows that of the Summer Treatment Program, where counselors utilize a comprehensive point system that is part of a token economy to evaluate children’s behaviors (ADHD summer treatment program). I will be working with other counselors led by Dr. Hallie Fetterman Ph.D., a pediatric psychologist, to deliver the program and evaluate the behaviors of sixteen children. The program is split into three age groups: six through …


The Effects Of Habitual Temperature And Diet On Crayfish Physiological Processes, Tyler D. Deramo, Sunny Rana, Victor Popoviciu Jan 2026

The Effects Of Habitual Temperature And Diet On Crayfish Physiological Processes, Tyler D. Deramo, Sunny Rana, Victor Popoviciu

Williams Honors College, Honors Research Projects

We will use crayfish to test the individual and combined effects of temperature and diet to see how they impact physiological processes such as metabolism, growth rate, molting patterns, and behavioral analysis. A total of forty-eight crayfish will be used throughout the experiment, and they will be housed in separate containers. A plant-based diet (consisting of fresh kale) and an animal-based diet (consisting of dried bloodworms) will be tested alongside room temperature (~18 degrees Celsius) and a warmer habitual temperature (~24 degrees Celsius). Metabolism will be measured via O2 consumption, and growth will be measured by weighing and measuring the …


Toadally Not A Frog: A Neuromuscular Physiology Study, Iris Renna Jan 2026

Toadally Not A Frog: A Neuromuscular Physiology Study, Iris Renna

Williams Honors College, Honors Research Projects

Upper-level physiology labs in undergraduate education use freshly isolated bullfrog and/or leopard frog tissue to teach core concepts in nerve and muscle physiology. Sourcing live animals for routine educational use raises ethical and conservation concerns. Cane toads (Rhinella marina) are an invasive species that are routinely culled, can provide a potential source of laboratory animals which would remove pressure to native amphibian populations. This study tested the hypothesis that cane toads can serve as a functional substitute for bullfrogs and/or leopard frogs in the muscle and nerve physiology lab. Isolated sciatic nerve and gastrocnemius muscle preparations from cane …


Methods Of Euthanasia In Laboratory Animals, Jaiden L. Corley Jan 2026

Methods Of Euthanasia In Laboratory Animals, Jaiden L. Corley

Williams Honors College, Honors Research Projects

The current honors research project will focus on the current use of carbon dioxide (CO2) as a means of euthanizing laboratory mice. CO2 is commonly used as a means of euthanizing laboratory animals and has been a standard of practice for mamy years. it is regarded as fast, painless, and efficient in overwhelming the respiratory control centers of the brainstem and resulting in respiratory depression and death. However, there continues to be debate and ongoing research regarding the 'humaneness' of this approach to euthanasia, and the American Veterinary Medicine Association (AVMA) suggests the inclusion of isoflurane (a volatile anesthetic) as …


The Right To Seek Joy, Tyler Rose Clemons Jan 2026

The Right To Seek Joy, Tyler Rose Clemons

Faculty Publications

Within the past three years, roughly half of American states have restricted access to gender-affirming medical treatment for children. In this article, I argue that these bans violate transgender children’s right to liberty guaranteed by the Fourteenth Amendment’s Due Process Clause. I do so by excavating the Framers’ understanding of liberty as the right to seek joy. Rooted in the philosophies of John Locke and Epicurus, the Framers understood liberty as the right to make important life decisions according to one’s subjective preferences without undue interference from the government. Based on this understanding, I develop a new framework for substantive …


Presidential Slaves: The Story Of Black People In The Lives Of Antebellum U.S. Presidents, Nika Davis Jan 2026

Presidential Slaves: The Story Of Black People In The Lives Of Antebellum U.S. Presidents, Nika Davis

History Dissertations

The historical narrative about American slavery included many topics such as the African slave trade, the Middle Passage, slave culture, rebellions, religion, and abolition.  This study revealed more information to be examined in the record of American slavery relating to the presidents of the United States and their enslaved laborers.  This oversight proved prevalent during the years leading to the American Civil War from 1820-1860.  Therefore, this dissertation focused upon the enslaved and free Black people who intersected with the presidents and their friends, political acquaintances, and family.  By studying their lives, this dissertation revealed that the slaves associated with …


Red Clover Isoflavones And Establishment In The Context Of Tall Fescue Toxicosis Mitigation In The Mid-South, Jonathan L. Stephens Jan 2026

Red Clover Isoflavones And Establishment In The Context Of Tall Fescue Toxicosis Mitigation In The Mid-South, Jonathan L. Stephens

Theses and Dissertations--Plant and Soil Sciences

Low levels of red clover (Trifolium pratense L.) have been shown to mitigate tall fescue (Lolium arundinaceum (Schreb.) toxicosis symptoms. This is because of the presence of plant-produced compounds known as isoflavones. Production of a red clover supplement on a commercial scale would require industrial-level processing of raw plant material into granules or pellets. The first study of this thesis evaluated the impact of drying temperature on bioavailability of isoflavones. Drying temperatures up to 104°C had minimal impact on isoflavone concentrations. Additionally, varietal differences in isoflavone concentrations were documented. The second study of this thesis evaluated optimal establishment …


Characterizing The Role Off The Sp1/Klf Transcription Factor Huckebein In The Drosophila Melanogaster Ventral Nerve Cord, Benjamin Almond Jan 2026

Characterizing The Role Off The Sp1/Klf Transcription Factor Huckebein In The Drosophila Melanogaster Ventral Nerve Cord, Benjamin Almond

Distinguished Undergraduate Researcher Program

Over the course of embryonic development, the ectodermal cell layer gives rise to a vast array of neurons and glia patterned across the central nervous system (CNS). Neurulation and specification is achieved in the ectoderm through temporospatial patterns of transcription factor (TF) expression, many of which are conserved across evolutionary history. These conserved regulatory motifs allow the use of Drosophila melanogaster to study the mechanisms of neurodevelopment across the animal kingdom. The huckebein (hkb) gene encodes a conserved SP1/KLF TF known to play important roles in cell cycle regulation, tissue morphogenesis during tubular organ development, and gut specification in Drosophila. …


Examining The Pre-Columbian Use Of Psychotropic Plants In The South American Andes: Tobacco, Coca, And Ayahuasca, Jalayne Allison Jan 2026

Examining The Pre-Columbian Use Of Psychotropic Plants In The South American Andes: Tobacco, Coca, And Ayahuasca, Jalayne Allison

Distinguished Undergraduate Researcher Program

This thesis offers a literature review that traces the origins and variations in the use of tobacco (Nicotiana sp.), coca (Erythroxylum coca spp.), and ayahuasca (Banisteriopsis caapi) in the Andean highlands and Amazon region along the western coast of South America. This mountainous region stretches across seven countries: Venezuela, Colombia, Ecuador, Peru, Bolivia, and Argentina. Diverse South American Indigenous groups and ancient civilizations, such as the Inca Empire, have inhabited this area. This review delves into key concepts of Andean cosmology, especially those related to ecology and hydrology as interpreted through Inca beliefs. These concepts are pivotal in the application …


Physiological Leptin Replacement Does Not Reverse Metabolic Adaptations To Starvation In Sprague Dawley Rats, Sydney Junot, Layla Deprimo, Camille Meaux, Arline Narez, David Mcdougal Jan 2026

Physiological Leptin Replacement Does Not Reverse Metabolic Adaptations To Starvation In Sprague Dawley Rats, Sydney Junot, Layla Deprimo, Camille Meaux, Arline Narez, David Mcdougal

Distinguished Undergraduate Researcher Program

Historically, low insulin levels were the signaling event considered responsible for metabolic adaptations to starvation, such as increased sympathetic outflow and increased serum levels of ketones, glucagon, and free fatty acids. Leptin, a hormone produced by adipose tissue, is known to decrease in response to caloric restriction. Recent work in the field suggested that leptin infusion in the final hours of a 48-hour fast reversed all metabolic adaptations to starvation, thus raising questions about an underappreciated role of leptin in the starvation response. This study tested whether physiological leptin replacement, maintaining fed plasma leptin concentrations, during a 72-hour fast in …


Developing A Comparative Framework For Organic Matter Loss Using Standardized Soils To Mimic Urbanized Areas, Madison Woodson, Michael (M.P.) Hayes Jan 2026

Developing A Comparative Framework For Organic Matter Loss Using Standardized Soils To Mimic Urbanized Areas, Madison Woodson, Michael (M.P.) Hayes

Distinguished Undergraduate Researcher Program

Rapid urbanization is an ongoing challenge to the natural ecosystem across Louisiana as the state invests in development to accommodate the challenges of flooding in nearby towns and cities. Across Louisiana waterways, flooding from urban developments along with coastal subsidence and relative sea level rise increase the transport of complex organic matter into local water channels. These events lead to higher concentrations of nutrients, specifically bioavailable carbon which can be lost from breakdown of soil organic matter in water. To better understand and predict organic matter transportation due to flooding events caused by urbanization, we studied the availability of organic …


Impacts Of Real Microplastic Leachates On The Development And Behavior Of Developing Zebrafish (Danio Rerio), Emma Tsai, Melanie Wilson, Mohamed Ateia, Ahmed Abdelmoneim Jan 2026

Impacts Of Real Microplastic Leachates On The Development And Behavior Of Developing Zebrafish (Danio Rerio), Emma Tsai, Melanie Wilson, Mohamed Ateia, Ahmed Abdelmoneim

Distinguished Undergraduate Researcher Program

Plastic pollution in aquatic environments has increased, raising concerns about the toxicity of microplastics (MPs) and their additives to developing organisms. Additives from the MPs can desorb into the surrounding environment, generating leachates that may impact early development. This study evaluated the effects of early developmental exposure to MP leachates on early developing zebrafish (Danio rerio), quantifying effects on larval survival, development, activity, and behavioral responses to acute stressors. MPs—acrylonitrile butadiene styrene (ABS), polyethylene terephthalate (PET), polyamide 66 (PA66), and reinforced glass fiber (MIX)—were processed into particles (< 500 µm) and incubated in embryo media for 24 hours under UV-C, 35 °C, and agitation to generate leachates. Zebrafish embryos were exposed from 6 to 120 hours post-fertilization (hpf) to varying leachate dilutions (corresponding to 0.063 to 10,000 mg MPs/L). At 120 hpf, larvae were assessed for survival, prevalence of morphological defects, overall growth, baseline activity, and behavioral responses to acoustic, visual, and peripheral irritant stressors. MIX leachate significantly increased mortality, while PET leachate exposure reduced growth. No significant morphological defects were observed across treatments. ABS, PA66, and PET leachates altered larval activity and behavioral stress responses. These preliminary findings suggest that MP leachates pose varying developmental and behavioral risks to developing organisms at critical exposure concentrations. Understanding these risks is crucial for assessing the environmental impact of MPs pollution and informing regulatory policies.


Bird Diy: Building An Rfid System To Study Behavior In Free-Living Starlings, Raedan Stephens, Keegan Stansberry, Christine Lattin Jan 2026

Bird Diy: Building An Rfid System To Study Behavior In Free-Living Starlings, Raedan Stephens, Keegan Stansberry, Christine Lattin

Distinguished Undergraduate Researcher Program

Radio Frequency Identification (RFID) technology can be effectively utilized to gain insights into animal behavior, such as avian responses to environmental change. In our established field system of free-living European starlings (Sturnus vulgaris), we sought to implement a new system of RFID readers with antennas encircling the entrances of bird boxes and RFID leg bands with unique identifiers that record when birds pass through the antennas. To limit costs, we used Arduino RFID readers built by Eli Bridge and Jay Wilhelm and constructed the rest of the system components ourselves. We designed and 3D printed a new device to efficiently …


Mtor Signaling And Macrophage Recruitment In Polypterus Senegalus, Icyss Sargeant Jan 2026

Mtor Signaling And Macrophage Recruitment In Polypterus Senegalus, Icyss Sargeant

Distinguished Undergraduate Researcher Program

Tissue regeneration is marked by significant macrophage activity. Macrophages aid in signaling pathways for tissue growth and differentiation. Salamanders are the only limbed vertebrates capable of complete limb regeneration. However, Polypterus senegalus can fully regenerate its fins after injury. It has been determined that mTOR signaling by macrophages is active in early regeneration. In this project, we will test whether mTOR signaling is necessary for the recruitment of macrophages to regenerate fins in Polypterus senegalus. We began with immunofluorescence of liposomes in tissue sections to quantify macrophages recruited by mTOR signaling in fish treated with DMSO and RAPA. RAPA has …


Measuring The Rise And Fall Of Plasma 25-Hydroxyvitamin D Concentrations In Blue-Tongued Skinks (Tiliqua Scincoides) Following Ultraviolet B Exposure And Withdrawal, Ashleigh Godke, Haerin Rhim, M. Graciela Aguilar, Keishla Marrero-Acosta, Mark Mitchell Jan 2026

Measuring The Rise And Fall Of Plasma 25-Hydroxyvitamin D Concentrations In Blue-Tongued Skinks (Tiliqua Scincoides) Following Ultraviolet B Exposure And Withdrawal, Ashleigh Godke, Haerin Rhim, M. Graciela Aguilar, Keishla Marrero-Acosta, Mark Mitchell

Distinguished Undergraduate Researcher Program

Species-specific husbandry guidelines remain limited for blue-tongued skinks (Tiliqua scincoides), especially in relation to ultraviolet B (UVB) lighting and vitamin D requirements. This study aimed to determine whether UVB exposure is necessary for these skinks and how long 25-hydroxyvitamin D (25-OHD) concentrations persist after UVB withdrawal. Eleven adult skinks who had been fed with wet cat food were exposed to 12 or 2 h of UVB per day for four weeks. Plasma 25-OHD concentrations were very low at the baseline, and significantly increased post-UVB in both groups (p < 0.01), with the 12-hour group increasing from baseline concentrations of 18.5 [12.8–20.5] nmol/L to 820 [730–1251.3] nmol/L and the 2-hour group increasing from baseline concentrations of 22 [15.5–22] nmol/L to 635 [401–892.5] nmol/L. Following the discontinuation of UVB exposure, 25-OHD gradually declined and was not significantly different from baseline concentrations at 7 and 4 months for the 12-hour and 2-hour groups, respectively. Dietary vitamin D3 (2.5 IU/g as dry matter basis), provided through wet cat food alone, appeared insufficient to support sustained plasma 25-OHD concentrations. These findings strongly suggest that blue-tongued skinks rely on UVB exposure to increase their 25-OHD concentrations. Moreover, the shorter 2-hour exposure provided a significant rise in 25-OHD concentrations and remained above baseline for 4 months, suggesting the shorter exposure can benefit these animals, while potentially reducing secondary risks associated with UVB exposure.