Environmental Health and Protection Commons^™

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 …

When Words Flow Like Water: How The Enbridge Line 3 Pipeline Environmental Impact Statement Failed To Prevent Hydrogeologic Harm In Minnesota, Carly Gutzmann

Journal of Earth and Life Science

For the aquifers of Minnesota, the environmental impact statement (EIS) was a promise of protection that never left the page. An environmental impact statement is meant to be an aid in the decision making process in order to ensure that projects consider potential environmental harms that may occur. However, they are often used instead as another regulatory box to check, rather than as active considerations when planning. As such, a project plan can be flawed from the start—if project developers only consider environmental impacts after they have already put considerable time, effort, and funding into their project as-is, they may …

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. …

Indigenous Land Seizure & Environmental Injustice: Impacts Of Settler Colonialism, Lydia Moorman

Journal of Earth and Life Science

The fields of conservation and environmentalism prioritize ecosystem health, yet both emerged from western frameworks that displaced and criminalized Indigenous land stewardship. The idealization of “pristine wilderness” narratives served to justify the removal of Indigenous peoples from their homelands and erased millennia of sustainable land stewardship that had maintained ecological balance long before western conservation existed. These narratives not only misrepresented Indigenous relationship with land but also constructed a false dichotomy between humans and nature that positioned Indigenous presence as a threat rather than a source of ecological knowledge. Simultaneously, anthropogenic expansion; such as pipelines, mining, railroads, and other extractive …

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 …

Navigating Wastewater: Minnesota Mining Wastewater Permit Challenges And Evolving Compliance Standards, Madelaine Adamich

Journal of Earth and Life Science

February of 2021 marked the beginning of Minnesota clearly establishing that groundwater qualifies as a Class 1 water in a legal battle involving United States Steel, the Minnesota Pollution Control Agency, WaterLegacy, Fond du Lac Band of Lake Superior Chippewa, the Minnesota Court of Appeals, and eventually the Minnesota Supreme Court (MNSC). Minnesota has a water classification system, as required by the federal Clean Water Act, with 7 classes of use. Class 1 waters are waters used for domestic consumption (MPCA 4, n.d.). According to Minnesota Statute § 7050.0220, the acceptable level for sulfate is 250 mg/L in Class 1 …

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 …

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 …

Effects Of Round-Up On The Environment, Sandra J. Marcu

Journal of Earth and Life Science

Many people around the world have used and still currently use Roundup but are unaware of the effects it has on the environment. Roundup is a spray on application weedkiller that is widely used around the world today both residentially and commercially. It enables its user to grow a garden or a field of crops with a no-tilling approach to eliminate weeds. It is a well-known and popular choice for killing weeds that has been around since the mid 1970’s (Oca, 2017). John Franz, a Monsanto scientist discovered that glyphosate (main ingredient in Roundup) was an herbicide or weedkiller, and …

The Effectiveness Of The Minnesota Buffer Law And Its Impacts On People, Ellen P. Isakson

Journal of Earth and Life Science

In January 2015, the then-governor of Minnesota Mark Dayton announced new legislation that would require 50-foot vegetation buffers along all waterways in Minnesota; this legislation would come to be known as the Minnesota buffer law, exact requirements being “perennial vegetative buffers of up to 50 feet along lakes, rivers, and streams and buffers of 16.5 feet along ditches” (Albert, 2017; MN Board of Water and Soil Resources [MN BWSR] 4 ). A buffer in the context of vegetation and natural resource management is a strip of vegetation around a body of water “designed to intercept stormwater runoff and minimize soil …

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 …

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 …

Spatial And Temporal Variability Of Mercury In Upper And Lower Red Lake Walleye, Tyler Orgon

Biology Graduate Theses

Mercury is a global pollutant that is released into our environment by natural and anthropogenic processes resulting in extensive studies conducted on mercury cycling in aquatic ecosystems which has led to the issuance of human-health-based fish-consumption advisories. We examined total mercury concentrations in Walleye Sander vitreus from Upper and Lower Red Lakes, located in north central Minnesota, between 2019 and 2020. Upper and Lower Red Lake form a contiguous water body consisting of two large (483.1 and 665.6 km2, respectively) basins that are naturally connected by a 1.4 km-wide strait. Both basins are important fisheries for recreation, subsistence, and commercial …

Analysis Of Hematocrit Levels In Walleye Sander Vitreus From Similar Waterbodies, Alyssa Hauser

Journal of Earth and Life Science

Walleye Sander vitreus are a popular fish among anglers and hold a prominent place in Minnesotan’s identity as their state fish. Because of this, multiple management practices are used to ensure the continued health of their populations within Minnesota waters. In this study, the process of analyzing hematocrit levels was used to determine if the analysis of hematological parameters could be a useful tool in detecting differences in population health. To evaluate this, blood samples were acquired from age-0 and age-1 fish from two similar lakes and run through a hematocrit centrifuge to separate platelets from plasma to read the …

Zebra Mussel Length-Weight Relationships Across Various Substrate Types In Lake Bemidji, Mitch Kehne

Journal of Earth and Life Science

As of November 2021, zebra mussels were confirmed in 270 Minnesotan lakes with another 232 lakes listed as infested due to their connection or proximity to where zebra mussels have been found. With lack of effective treatments to impede their spread, zebra mussels continue to colonize new areas causing ecological as well as economic harm. The goal of this study was to establish a length-weight relationship for the zebra mussel population in Lake Bemidji using shell length (SL) and wet weight (WW), as well as to assess substrate type and log transformed shell length as predictors of log transformed zebra …

Exploring The Genetic Variability Of Zebra Mussels Dreisenna Polymoprha, Maxwell Carr

Journal of Earth and Life Science

Zebra Mussels Dreisenna polymorpha are one of the most well-known invasive species here in the United States. This species can take over watersheds very quickly, causing damage to both the ecosystem and man-made structures. The basic physical behavior of this species has been well documented, but the invasive North American Zebra Mussel is much more aggressive and therefore causes more damage in the Great Lakes region compared to its native waters. Genetic variation may be playing a very large role in how and why D. polymorpha is causing such large problems for stakeholders in the United States. This review cites …

Effectiveness Of Endothall Treatment In Reducing Potamogeton Crispus In Lake Julia, Jake Sorensen

Journal of Earth and Life Science

Curly leaf pondweed Potamogeton crispus, is a submerged aquatic plant non-native to North America. It was most likely introduced when common carp Cyprinus carpio were intentionally brought to the Midwest. Endothall is an aquatic herbicide commonly used to control curlyleaf pondweed in lakes. This study focused on collecting data from Lake Julia in Sherburne County, MN. Lake Julia is treated annually in the spring to control curlyleaf pondweed. The results show treatment areas saw a significant increase in vegetation density compared to control areas (P < 0.01). Changes in percent vegetation coverage by date were insignificant (P = 0.24). No significant signs of fish kills were observed. Because this study looked at overall vegetation coverage instead of specifically curlyleaf pondweed, we cannot conclude the increase in vegetation coverage was from curlyleaf pondweed alone. Based on the results from Poovey et al. (2002) we would expect lower vegetation coverage in treatment areas instead of the increased vegetation coverage observed in our study. This suggests the possibility that the endothall treatment successfully killed curlyleaf pondweed in treated areas, which allowed for new growth of submerged aquatic plants to take place as water temperatures increased.

Age-0 Walleye Growth Rates Following Spiny Water Flea Bythotrephes Longimanus Invasion, Joseph Amundson

Journal of Earth and Life Science

Within Voyageurs National Park, spiny water flea Bythotrephes longimanus has reduced Lake Kabetogama and Rainy Lake native zooplankton biomass during summer peak by 40-60%. Subsequently, planktivorous age-0 Yellow Perch Perca flavescens growth has decreased. A possible trophic cascade may influence predatory fish growth rates like that of age-0 Walleye Sander vitreus. Using seine net and electrofishing data, age-0 Walleye growth rates were modeled as a linear function of growing degree days (GDD) and the slope was compared between pre- and post-spiny water flea establishment. Nearby Lake Vermilion, assumed to have been unaffected by spiny water flea until 2015 and …

Estimating Seasonal Variation In Condition Of Yellow Perch, Emily Anne Powers

Biology Graduate Theses

Research has shown that Yellow Perch Perca flavescens, found throughout lakes and streams of North America, are good indicators of environmental health. Due to the correlation between fish condition and ecosystem health it is essential to reliably estimate condition to better manage our fisheries. Therefore, the study objectives were to measure the seasonal changes in adult Yellow Perch percent dry weight (PDW), and compare the reliability of bioelectrical impedance analysis (BIA) and morphometric-based estimates of condition. The seasonal fluctuations in average monthly PDW were measured over a two- year period and were sinusoidal in shape with peaks in August 2015 …

Effects Of River Current Inflow On Dissolved Oxygen And Temperature Of Refuge Zones For Cisco In Lake Bemidji, Bryant C. Swenson

Journal of Earth and Life Science

The objectives of this study were to (1) determine if the inflow current from the Mississippi River affects temperature and dissolved oxygen in Lake Bemidji, (2) determine how the amount of suitable cisco Coregonus artedi habitat changes over the summer in Lake Bemidji, and (3) predict how much cisco habitat would be available under a climate warming scenario. Summer fish kill of cisco occurs in most years on Lake Bemidji resulting from low dissolved oxygen in the hypolimnion and high water temperatures in the epilimnion. Dissolved oxygen and temperature profiles provided evidence to suggest the north basin is more suitable …

Changing Body Condition In Walleye With Reference To Ideal Sample Size Requirements, Kevin Longtin

Journal of Earth and Life Science

The objective of this study was to determine if walleye Sander vitreus percent dry weight, a measure of condition, differed among summer months of 2014 on Maple Lake, Minnesota. A second objective was to determine if there was a relationship between condition and body temperature, total length, or wet weight. Between three and six walleyes were collected per month by hook and line methods. All fish had internal body temperatures taken at the time of capture and were oven dried in the laboratory at 80 °C in order to measure percent dry weight. There was no relationship between condition and …

Defining The Physiochemical, Biological And Habitat Requirements For The Upper Extant Of Oncorhynchus Mykiss Distribution, Emily Powers

Journal of Earth and Life Science

The distribution of rainbow trout is strongly influenced by their habitat. As climatic conditions change, the distribution of rainbow trout populations will change along with them. The objective of this study was to identify the particular habitat parameters that rainbow trout select for in this lotic system and to specifically assess how this relates to the upper extant of their distribution. By assessing the distribution of the upper extant specifically, future research may be conducted to better assess climatic changes on a small and/or large scale basis. A 9,000 m section of the Clearwater River was used as the study …

Winter Survival Strategies Of Benthic Invertebrates In Temporary Habitats In A Northern Minnesota Lake, Cal Oldenburg

Journal of Earth and Life Science

During the winter months in the northern hemisphere, above 40 degrees latitude, a freezing event occurs that can last several months. Some lakes may have large portions of the shallow littoral zone frozen completely solid down into the sediments. Invertebrates affected by these events have developed survival strategies to cope with the harsh environment. The two main strategies for invertebrates in these areas are to either migrate to a different area and recolonize the original area when it becomes available again, or to burrow into the sediments and withstand the freezing. A 1- month study took place on Lake Bemidji …

Senior Internship With River Keepers, Christine Hokkala-Kuhns

Honors Capstones

Capstone submitted as a graduation requirement for BSU Honors Program.

Nepa And The Dynamics Of Public Participation In The Environmental Review Process: An Analysis Of The Northmet (Polymet) Mining Project Near Hoyt Lakes Minnesota, Amber Neumann

Political Science Theses and Capstones

Hypothesis: That comments collected from agency “experts” during the scoping phase of the National Environmental Policy Act (NEPA) process would be disproportionately represented as changes in subsequent drafts of NorthMet’s Environmental Impact Statement (EIS).

Methods: Tabular analysis of data collected from the Minnesota DNR publication of Response to the Public Scoping Projects PolyMet Mining Inc.; NorthMet Project. 2005

Results: There is an excellent cross section of comment sources represented in changes to subsequent drafts of NorthMet’s EIS. A lot of overlap exists between various types of participants and their concerns, resulting in many of the successful comments stemming from …

Case Studies Of Urban And Rural Lakes In Minnesota, Lisa M. Becker

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.