Laboratory and Basic Science Research Commons^™

Fish Tissue Digestion And Microplastic Polymer Identification Protocol Using Open-Source Ftir Database, Shawn L. Kissinger, Vick-Ariel Privert, Jason Bystriansky, Kyle A. Grice

DePaul Discoveries

Microplastic (MP) contamination in aquatic ecosystems poses significant concerns for environmental and public health, as seafood represents a critical food source worldwide. Despite increasing evidence of MP presence in marine organisms, efficient and accessible detection methods remain essential for characterizing contamination patterns and informing regulatory frameworks. This study extracted MPs from brain, gill, intestine, liver, and muscle tissues of gilt-head bream (Sparus aurata) and European sea bass (Dicentrarchus labrax), two commercially important species from the Gulf of Cádiz, Spain, using a NaOH–HNO₃ chemical digestion protocol. Isolated particles were characterized by Fourier Transform Infrared (FTIR) spectroscopy, with …

Determining Cave Presence And Diet Variation Of The Ozark Big-Eared Bat (Corynorhinus Townsendii Ingens) From Guano Dna, Lark E. Sybrant

ATU Theses and Dissertations 2021 - Present

The Ozark big-eared bat (Corynorhinus townsendii ingens; OBEB) is federally endangered in Arkansas, where it persists in a few small, geographically restricted populations within the Ozark National Forest. Although the region contains many caves that appear suitable for OBEB, expanded survey efforts are needed to locate additional roost sites for monitoring and protection. Effective conservation also requires a clear understanding of their distribution and diet. Traditional cave surveys can be disruptive and often miss cryptic species, and earlier diet studies based on manually sorting prey remains provided only coarse taxonomic resolution and overlooked soft‑bodied insects. To address these …

Enhancing Walleye (Ogaa) Recruitment: Evaluating Assisted Reproduction As A Mitigation Strategy, Douglass Keiser

Biology Graduate Theses

Over the past several decades, cold- and cool-water fish populations across the Upper Midwest, including Minnesota and Wisconsin, have shown troubling signs of decline. Among the most affected is the walleye/Ogaa (Sander vitreus), a species deeply embedded in the ecological balance, cultural identity, and economic vitality of the region, and central to the lifeways, treaty-reserved rights, and resource stewardship of Tribal Nations, including Ojibwe communities across the Upper Midwest. Despite ongoing stocking efforts and harvest regulations, many lake systems have experienced persistent declines in natural recruitment, prompting resource agencies to investigate the underlying causes. One such system is …

Trophic Structure And Mercury Bioaccumulation In Walleye And Yellow Perch In The Upper And Lower Red Lake Basins, Marissa Pribyl

Biology Graduate Theses

Mercury is a persistent global contaminant that biomagnifies through aquatic food webs, with dietary and environmental factors serving as the primary drivers of accumulation in fishes. Trophic structure and methylmercury dynamics in Walleye (ogaa; Sander vitreus) and Yellow Perch (asaawens; Perca flavescens) were investigated in the Upper and Lower Red Lake basins in Red Lake, Minnesota, during 2024-2025. Diets of Walleye and Yellow Perch were assessed through stomach dissections, and tissue samples from both species were analyzed for total mercury concentrations. Additional analyses included shiners (gigoozens; Notropis spp., Hudsonius spp.) along with a variety of freshwater fish and …

Design And Functionalization Of A Hierarchical Cu-Btc/Zeolite A4 Composite With Tannic Acid For High-Performance Heavy Metal Removal: Synergistic Adsorption Mechanisms, Kinetic Insights, And Reusability Evaluation, Samar A. Salim

Nanotechnology Research Centre

This study presents the development of a novel multifunctional adsorbent Cu-BTC (HKUST-1)/Zeolite A4 composite functionalized with tannic acid—for the efficient removal of toxic heavy metal ions (Pb²⁺, Cd²⁺, Cr(VI)) from aqueous solutions. The composite was synthesized via a solvothermal process and systematically characterized by XRD, FTIR, SEM-EDS, and BET surface area analysis. The resulting material exhibited a high specific surface area (1050 m²/g), a hierarchical pore structure, and a homogeneous distribution of active sites. Batch adsorption experiments revealed superior adsorption capacities of 220 mg/g for Pb²⁺, 180 mg/g for Cd²⁺, and 150 mg/g for Cr(VI) at pH 6, surpassing those …

Largemouth Bass Diet Changes Through The Summer In Central Minnesota, Ethan Kunz

Journal of Earth and Life Science

Largemouth Bass Micropterus nigricans is one of the most widespread fish species in the world, due in part to human introduction for angling. Largemouth Bass are opportunistic predators that will consume the largest prey they can often find; however, it has been shown that their diet mainly consists of invertebrates such as crayfish, with less focus on other fish species. This research aimed to determine what the Largemouth Bass diets in Central Minnesota consist of, and how they may change from the beginning of summer through the beginning of fall. A total of 174 Largemouth Bass were sampled from late …

Effectiveness Of Walleye Stocking In Winter Kill Lakes, Tyler Haus

Journal of Earth and Life Science

Winter kill events, marked by extensive fish mortality due to hypoxic conditions under the ice, are a common phenomenon in shallow eutrophic lakes, especially in the northern lakes in the northern United States. These events can drastically alter fish communities and often result in the elimination of top predators. Though these lakes will typically slowly bounce back to what they were in a couple of years. This study evaluates the effectiveness of walleye, Sander vitreus, stocking in lakes after a winter kill. For this study, four known winter kill lakes that are consistently stocked with walleye were studied. Pre- …

Assessing Urban–Rural Differences In Largemouth Bass Abundance In Minnesota, Jonathan Gates

Journal of Earth and Life Science

Urbanization can significantly alter freshwater ecosystems and influence sport fish populations. This study examined differences in largemouth bass Micropterus nigricans catch-per-unit-effort (CPUE) between urban and rural lakes in Minnesota and evaluated temporal changes between 2000–2010 and 2011–2021. Forty lakes (20 urban, 20 rural) were selected using Minnesota Department of Natural Resources fisheries survey data. Lakes were classified using NLCD 2019 land cover data, with ≥10% developed land designated as urban. Nonparametric analyses (Wilcoxon rank-sum and signed-rank tests) were used to assess spatial and temporal differences in CPUE. Results showed that rural lakes had consistently higher median CPUE than urban lakes …

Neonicotinoid Bioaccumulation In Bluegill And Bullhead Within Lake Julia And Lake Zumwalde, Jake Stuber

Journal of Earth and Life Science

Brown Bullhead Ameiurus nebulosus, Yellow Bullhead Ameiurus natalis, and Bluegill Lepomis macrochirus are unique in their stark differences. Bullhead are scaleless bottom feeders that can tolerate high pollution and low O₂ conditions. In contrast, Bluegill are scaled, aggressive nesters and are less tolerant of high pollutants or low-oxygen conditions. Among these pollutants include a class of chemicals called neonicotinoids (hereafter referred to as neonics). Neonics are a class of insecticides primarily used within agriculture and pest management. Due to the effectiveness, application has escalated on a global scale. They have been well documented by many toxicology assessments. …

Unsaturated Fatty Acid Oil-Based Microdroplets: A Promising Novel Class Of Microdroplets, Ramiz S. Alejilat

Seton Hall University Dissertations and Theses (ETDs)

Droplet-based microfluidics has rapidly advanced numerous fields, including chemistry, biology, materials science, medicine, food science, and cosmetics. In these systems, fluorocarbon oil combined with fluorinated surfactants is the preferred medium for fluid encapsulation, offering exceptional stability and biocompatibility essential for sensitive biological and chemical processes. However, growing concerns about the environmental and biological risks associated with fluorinated chemicals have prompted a search for alternatives.

This study is the first to explore the use of unsaturated fatty acids derived from emu oil for microdroplet formation. We characterized droplet formation based on flow rates and the presence non-fluorinated surfactant at a certain …

Modeling Wild Rice Bed Health: A Dual Metric Approach For Bed Strength And Invasive Impact, Seth Sisneros-Martinez

Journal of Earth and Life Science

Wild rice (mannoomin; Zizania palustris) is an aquatic grain that grows in slow-moving rivers and shallow bays throughout northern Minnesota. In Headquarters Bay on Leech Lake, wild rice has served as a cultural staple for Indigenous communities for centuries. However, its population has declined in recent years due to multiple environmental issues. One potential contributor is Eurasian watermilfoil (Myriophyllum spicatum; EWM), an invasive species that forms dense mats capable of outcompeting native aquatic vegetation, including wild rice. EWM was first recorded on the southern shoreline of Leech Lake in 2005 and has since become widespread. This study …

The Effect Of Zebra Mussels On Minnesota Fish Communities, Benjamin D. Strei

Journal of Earth and Life Science

Zebra mussels Dreissena polymorpha are an aquatic invasive species that has been spreading quickly throughout Minnesota water bodies since 1989. Zebra mussels are known to change certain morphological conditions in lakes such as turbidity, phytoplankton abundance, and aquatic invertebrate populations. However, studies showing impacts of the infestation of zebra mussels on the health of a fish community have been hard to prove due to a lack of repeated surveys and a suite of other confounding variables such as natural and seasonal variability, plant community, and lake morphometry. Therefore, the objective of this study is to determine whether zebra mussels have …

Microsatellites Reveal The Population Genetic Structure Of Yellow Perch In Minnesota, Megan Boche

Journal of Earth and Life Science

When analyzing a population’s genetic makeup, looking at variation of individuals and populations is a crucial factor. The management of yellow perch will be aided by this information particularly in regard to stocking or relocation. Microsatellite loci were used to analyze the genetic population structure of yellow perch Perca flavescens within and among 29 sampling areas throughout Minnesota’s basins. Seven microsatellite DNA loci were evaluated, with heterozygosities ranging from 0.41 to 0.78. The Lower Mississippi basin samples showed higher numbers of alleles per locus and greater expected heterozygosities compared to other basins, with Lake Pepin (PEP) exhibiting the highest average …

Aquatic Invertebrate Populations In Roadside Wetlands In Relation To Water Characteristics, Ellen P. Isakson

Journal of Earth and Life Science

The continual habitat destruction and draining of wetland systems makes the need to understand the ecology of roadside wetlands all the more necessary. Roadside wetlands provide valuable habitat to countless aquatic invertebrates, which can provide insight into the health of the wetland system due to their diversity. The objective of this study was to analyze the populations of aquatic invertebrates in roadside wetlands in relation to water characteristics such as pH, salinity, conductivity, water depth and temperature, and dissolved oxygen. This was done by collecting samples of invertebrate populations from roadside wetlands, in addition to data on water quality characteristics …

Journal Of Earth And Life Science, Academic Year 2024-2025, Megan Boche, Nathan D. Pyburn, Ben Hoover, Jayden R. Alsleben, Hector Montoya, Jr, Reed Cumberland, Rose Kuhlmann, Ray Anderson, Ellie Isakson, Seth Sisneros-Martinez, Zanden Mellen, Quady Bernu, Cian Verbridge, Benjamin D. Strei, Madelaine Adamich, Arian Garcia, Tegwen Romportl, Sandra J. Marcu, Bemidji State University

Journal of Earth and Life Science

No abstract provided.

The Relationship Between Plant Density And Microplastic Concentration In The Water In Lake Bemidji, Mn, Arian Garcia

Journal of Earth and Life Science

Microplastics, plastic particles smaller than 5 mm, are an increasing environmental threat, particularly due to their widespread distribution and toxicity. While much research has focused on larger freshwater and marine ecosystems, the presence and impacts of microplastics in smaller inland lakes remain less understood. This study investigates the relationship between plant density and microplastic concentrations in Lake Bemidji, a smaller freshwater lake. A total of 30 water samples were collected across varying vegetation conditions, ranging from open water (0%) to 90% plant coverage. Microplastics were identified and categorized into six morphological types: fibers, fragments, films, spheres/beads, and foam. The samples …

A Sample Of Fish Communities In Beaver Ponds Of Northern Minnesota, Reed Cumberland, Rose Kuhlmann

Journal of Earth and Life Science

The North American beaver Castor canadensis is an ecosystem engineer and a keystone species to the environment. Beaver inhabit ponds and construct dams to build ponds that provide habitat for certain fish. Little information is provided on the species of fish that live in beaver ponds. The objective of this study is to sample the fish communities in beaver ponds while comparing the effectiveness of two styles of minnow traps. Twelve beaver ponds were selected in the Bemidji area to be sampled. The quantity and species caught in each style of trap were recorded to compare effectiveness of each trap …

Does Depth Affect Zebra Mussel Length In Scalp Lake?, Zanden Mellen

Journal of Earth and Life Science

Since its first sighting in 1996, zebra mussels Dreissena polymorpha have been confirmed in hundreds of Minnesota lakes. Not only were they found in lakes, but they are also found in rivers too. With lack of effective treatments to impede their spread, zebra mussels continue to colonize new areas causing ecological as well as economic harm. The objective of this study was to see if there was a relationship between a zebra mussel length and the depth, they are found using shell length (mm) and depth (cm). The comparison of zebra mussel length and depth was done by performing a …

Movement And Activity Of Burbot, (Mizay; Lota Lota) In A Spring-Fed Minnesota Lake, Abigail M. Fountain

Biology Graduate Theses

Burbot (Mizay; Lota lota) are a relatively unmanaged freshwater fish, important in many local Indigenous cultures, but often overlooked or maltreated in research, conservation, and fishing practices. As such, relatively little research has been conducted on Burbot, despite ecological significance as an indicator species. A recent resurgence in popularity as a target species, however, has prompted new research to inform management policies. The objectives of this study were to summarize Burbot movement by identifying patterns in swimming activity and identify possible predictors of the movement observed. This study investigated the movements of 39 individuals implanted with acoustic transmitters in Bad …

Informing Management Of American Shad (Alosa Sapidissima) In The Carolinas: Evaluating Novel Fish Passage Approaches And Acoustic Tracking Methods, Margaret Gaither

All Theses

Acoustic telemetry is a valuable tool for fisheries scientists to study the movements and migratory behaviors of aquatic organisms. A critical assumption of this method is that tagged fish exhibit similar behaviors and survival rates as their untagged counterparts. To investigate this, we conducted a 12-week laboratory study on adult American Shad (Alosa sapidissima) using gastroesophageal insertion of acoustic transmitters. We implanted 80 fish with dummy transmitters and monitored tag retention and survival. Our analysis, employing a mixed effects Cox’s proportional hazards model, revealed no significant differences in survival between tagged and control fish, regardless of sex. Additionally, …

Microplastic Accumulation In The Marsh Periwinkle (Littoraria Irrorata), Sarah Keaton, Hannah Lukhard, Eli Windy, Manar Hasan

DePaul Discoveries

Contamination of oceans by microplastics (mm) currently poses a major threat to aquatic and terrestrial ecosystems worldwide. Recent attention towards this issue has raised questions about the extent to which microplastics have accumulated in the environment, and has led to an increase in studies on the effects of microplastics in various organisms. However, levels of contamination in protected natural areas are still largely unexplored, yet can offer an important empirical perspective on the issue. In addition, little is known about the potential effects of microplastics on behavior in the field. This research was conducted within the protected ACE Basin National …

Microplastic Quantification On The Effect Of Endoparasite Communities In Florida Seabirds, Sarah N. Prieto

All HCAS Student Capstones, Theses, and Dissertations

Microplastics are being studied in a variety of different projects to better understand their impact and threat to wildlife species. Although there is an understanding that microplastics are affecting our wildlife, there are still questions about how coastal seabirds come to ingest them and how the ingestion is altering critical biological processes, such as that for endoparasite communities. This project aims to determine a better understanding of two main objectives: assessment of the presence of secondary ingestion of microplastics in coastal seabirds due to the fish species they prey on and relationship between microplastics and endoparasite communities' structure and state …

Long Term Trends In Mortality Rates Of A Smallmouth Bass Population, Caleb D. Anderson

Journal of Earth and Life Science

Smallmouth bass Micropterus dolomieu are known as a popular sport fish for anglers. When a known smallmouth bass fishery appears to have a dwindling population, it raises questions about the population health. A common indicator of the health of the population is the mortality rate. By comparing mortality, conclusions can be made on whether smallmouth bass are dying at a different rate in the system over time. Therefore, the objective of this study was to see if there had been a significant change in smallmouth bass mortality over a span of thirty years in Round Lake (DOW:010204), Aitkin County, Minnesota. …

The Effects Of Length, Weight, Age, And Gender On Mercury Concentrations In Burbot In North-Central Minnesota Lakes, Liam Hanley

Journal of Earth and Life Science

Burbot Lota lota in north-central Minnesota lakes have the potential to reach large sizes and consume large volumes of prey. This caveat may make burbot susceptible to higher rates of biocontamination, bioaccumulation and biomagnification. The objective of this study was to determine how changes in age, length, gender, weight, and lake affect total mercury concentrations in burbot. In this experiment 28 burbot were angled from three lakes: Cass (n = 17), Winnibigoshish (n = 4), and Bad Medicine (n = 7). Then tissue samples were taken from each fish and were lyophilized and homogenized. Homogenized tissue samples were analyzed by …

Relationship Between Fishing Hours And Number Of Fish Harvested From Upper Red Lake, Dylan Ohlenkamp

Journal of Earth and Life Science

Total hours fishermen spend fishing and total amount of fish harvested per year are some of the most important pieces of knowledge gained from creel surveys. They provide crucial information that assesses fisheries mortality and pressure. MN DNR uses their results from creel surveys to improve or impose regulations, and to maintain healthy fisheries. Based on results from similar studies, there is expected to be a positive relationship between hours fished and fish harvested. To determine the relationship between these two variables on Upper Red Lake, data from two years were selected when the variables were at their highest and …

An Inkjet-Printed Graphene Oxide–Poly(3,4-Ethylenedioxythiophene) Poly(Styrene Sulfonate) Electrode For Nitrite Detection In Water, Budi Riza Putra, Weni Anindya, Mohamad Rafi, Ika Kartika, Yudi Nugraha Thaha, Aga Ridhova, Wulan Tri Wahyuni

Makara Journal of Science

In this study, a screen-printed electrode (SPE) for nitrite (NO₂⁻) sensing was fabricated through an inkjet printing technique using a commercial printer machine and preparing an ink composite solution containing graphene oxide (GO) and poly(3,4 ethylenedioxythiophene) poly(styrene sulfonate) (PEDOT:PSS) as conductive materials. The optimum ink materials for SPE fabrication comprised GO and PEDOT:PSS with binders that resemble the viscosity of commercial ink. The surface topography of the fabricated SPE, which was characterized using scanning electron microscopy and atomic force microscopy, showed a smoother surface compared to the commercial screen-printed carbon electrode, with conductive ink materials deposited primarily …

Fire Effects On Soil Organic Matter In The Creek Fire, Gracie E. Doolin

Master of Science in Environmental Sciences and Management Projects

Wildfires have increased in frequency and severity over the past few decades due to the increased concertation of CO2 emissions from anthropogenic influence. Soil carbon (C) sequestration has been identified as a climate change mitigation strategy; however, the influx of large-scale wildfires has accelerated landscape processes such as erosion, reducing soil aggradation, and soil C and nitrogen (N) protection. This trend is highlighted by the Creek Fire that occurred in September 2020 and burned 379,895 acres in the Sierra National Forest. This research is designed to close the knowledge gap regarding the impact of burn severity on soil organic matter …

Interactive Effects Of The Partial Pressure Of Co2, Temperature, And Nutrient-Limitation On The Physiology And Growth Of The Coccolithophore E. Huxleyi Grown On A 12:12 L:D Cycle Of Illumination, James Bradley

LSU Master's Theses

I studied the interactive effects of pCO2, temperature, and nutrient limitation on the growth and physiology of the marine coccolithophore, Emiliania huxleyi. This was done to look at the effect of climate change factors on the widespread and abundant calcifying marine organism as a predictor of what the future has to hold. The strain of E. huxleyi (PnB 272 B10) was grown on a 12:12 L:D cycle of illumination and exposed to either high or low pCO2 under nutrient-replete or nitrate-limited conditions across a temperature range of 10–28C. I examined the direct and interactive effects of temperature, pCO2, and nutrient …

Determination Of Cadmium Uptake In Crassostrea Virginica Shell Under Controlled Conditions, Joseph John Pavelites Ii

Graduate Theses and Dissertations (2019 - present)

The objective of this thesis was to meet growing demand for the development of environmental biomonitors that protect ecosystems and public health. To do this, I determined the potential of oyster shell as a bioindicator of cadmium (Cd) in the environment by determining the mode of Cd uptake and relationships between Cd concentrations in the environment, shell, and soft tissues of juvenile eastern oysters (Crassostrea virginica Gmelin). I performed a review of the literature on the ability of oyster shell to retain metal contaminants and the factors that could affect this process (Chapter 2). I then reared C. virginica …

Effects Of Velocity And Substrate Size On The Formation Of Zebra Mussel Druses, Ian Mott

Journal of Earth and Life Science

Zebra Mussels Dreissena polymorpha are an invasive bivalve species that are highly successful at dominating new environments. These invaders have been known to colonize substrate so thoroughly that all they have to attach to are members of their own species. When large mats of interconnected mussels completely cover a riverbed, it can have a drastic effect on the surrounding environment. This study serves to create a better understanding of the hydrologic parameters needed for Zebra Mussels to create these ecosystem-transforming colonies known as druses. Data was collected on a small stretch of the Upper Mississippi River in Northern Minnesota, previously …