Terrestrial and Aquatic Ecology Commons^™

Investigating The Mechanisms Of Freeze Tolerance In Lemna Minor, Tamara Bouchard

Honors Theses and Capstones

Freezing presents a significant abiotic stress to aquatic plants, yet little is known about the mechanisms by which species like Lemna minor (duckweed) survive subzero temperatures in nature. This study investigates whether L. minor employs freeze-avoidance or freeze-tolerance strategies and explores the potential role of its microbiome in enhancing cold resilience. Using both field-collected fronds from naturally frozen ponds and controlled freezing experiments in the lab, I assessed survival through viability staining and post-thaw survival. Results showed that L. minor can survive natural ice encasement and that prior cold acclimation significantly improves tissue survival under induced freezing. Trypan blue staining …

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.

Size Structure Of Black Crappie And Bluegill In Northern, Eastern, Western, And Southern Minnesota, Ray Anderson

Journal of Earth and Life Science

Fish size structure is an important factor in a fishery population. Panfish such as black crappie Pomoxis nigromaculatus and bluegill Lepomis macrochirus play a major role in the health of fisheries. Five lakes from southern, northern, eastern, and western Minnesota were selected for analysis. Data were collected using standard sampling methods, including gill nets, electrofishing, and fyke nets. Length-frequency distributions were created to assess size structure in each region. Relative abundance was measured using catch per unit effort. Data analysis included a one-way ANOVA to compare Proportional Size Distribution (PSD) values and the distribution of fish sizes among regions. Chi-square …

Comparison Of Hoop Nets To Trap Nets In Sampling Panfish, Jayden R, Alsleben

Journal of Earth and Life Science

Panfish including bluegill Lepomis macrochirus and black crappie Pomoxis nigromaculatus are gamefish species of significance found in Minnesota. Hoop nets and trap nets are two types of gear that can be used to sample these fish. Fisheries managers and anglers alike are interested in the best tactics to capture panfish. The behavior of fish, including bluegill and black crappie, change throughout the sampling season and make it difficult to assume accurate representations. Trap nets have historically been adequate in sampling near shore populations, but questions surrounding the gear have allowed other options to be pursued. The objective of this study …

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 …

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 …

Age Class Is Not Related To Size Or Composition Of Home Ranges Among Suburban White-Tailed Deer During Parturition, Nathan D. Pyburn

Journal of Earth and Life Science

How white-tailed deer use the landscape in an urban environment can help us understand the effects of urbanization on deer populations. White-tailed deer form observable matriarchal hierarchies in studied populations. This study examines the matriarchal structure, home range size, and home range composition of 25 collared white-tailed deer within the city limits of Bemidji, MN. The results found no significant difference between age class and home range size or composition. However, movement metrics from yearling and mature age classes were more similar than the juvenile age class females. I propose this is because social acceptance between mature females was higher …

Relationship Of Utricle And Trap Door Size On Common Bladderworts Utricularia Macrorhiza, Tegwen Romportl

Journal of Earth and Life Science

The common bladderwort Utricularia macrorhiza is a carnivorous aquatic plant that captures organisms with its bladders. This study was aimed at setting the stage for future research which might determine if U. macrorhiza could be a biological method of control for invasive species. The objective of this study was to determine the relationship between utricle and trap door sizes and to gather data on the size ranges of these two morphological features. A regression analysis was used to obtain results which showed there was enough evidence to suggest that the size of bladderwort trap doors have a significant, positive relationship …

Evaluating Dietary Consequences On Body Mass And Thermal Heat Flux Of North American Bison (Bison Bison) Yearling Heifers, Kendall Marie Wald

Electronic Theses and Dissertations

No abstract provided.

Spatial And Temporal Patterns Of Nutrient Limitation In A Western Montana River, Matthew T. Nichols

Graduate Student Theses, Dissertations, & Professional Papers

Enhanced loading of nitrogen (N) and phosphorus (P) is pervasive in rivers around the world. As a consequence of nutrient-rich conditions, many well-lit rivers experience severe algal blooms, which threaten water quality and aquatic habitats. Nutrient enrichment in the upper Clark Fork River, located in western Montana, has increased the productivity of benthic algae, Cladophora glomerata, which routinely forms extensive blooms during summer growing seasons (July – September). Addressing eutrophication in rivers begins with identifying the nutrients that contribute toward algal productivity. I deployed nutrient diffusing substrates (NDS), collected bi-weekly surface water samples, and conducted algal surveys at four …

Assessing Genetic Diversity And Population Structure In The Imperiled Aconitum Reclinatum (White Monkshood), An Endemic Wildflower Of Central Appalachia, Diamanda A. Zizis

Master’s Theses

Aconitum reclinatum, white monkshood (Ranunculaceae), is a Pennsylvania critically imperiled plant species found in five states of the Appalachian region of the United States: Pennsylvania, West Virginia, Virginia, North Carolina, and Tennessee. This plant is adapted to cool, moist environments but faces threats from increasing habitat loss, deer browse, logging, and changes in rainfall and temperature associated with climate change. Comprehensive knowledge of A. reclinatum genetic population structure remains limited. To address this, we collaborated with Natural Heritage programs within the range of A. reclinatum to sample populations across the species distribution and generate a genotyping-by-sequencing data set of …

Parallel Inquiries: Investigation Of Social Resource Use In Early Career Stem Teachers And Impacts Of Metal Pollution On Fingernail Clam Microbiome, Emily Hamada

EWU Masters Thesis Collection

No abstract provided.

Aspen Stands Enrich Bird Communities Following A Wildfire In A Montane, Mixed Conifer Forest, Cody Q. Lane

Graduate Student Theses, Dissertations, & Professional Papers

Fire is a major ecological force in most terrestrial systems, but the responses of animal communities to fire vary markedly across ecosystems due to variability in fire regimes and vegetation communities. Quaking aspen (Populus tremuloides) is unique within coniferous forests of western North America for its ability to regenerate following wildfire via vegetative resprouting. As managers employ techniques to restore fire regimes and conserve declining aspen forests, it becomes important to understand how aspen alters postfire communities. Our objectives were to (1) assess how aspen interacted with fire severity and years since fire to influence avian species and …

In The Clear: Timber Harvest Informs Elk Summer Nutrition And Resource Selection In A Densely Forested Landscape, Trevor C. Weeks

Graduate Student Theses, Dissertations, & Professional Papers

As wildlife and habitats face unprecedented challenges in the form of landscape conversion, shifting disturbance regimes, and climate change, it becomes increasingly important for land and wildlife managers to find avenues for collaboration as they seek to maintain habitat to support robust wildlife populations. Timber harvest may provide one such avenue for collaboration. It has been shown to increase the quality and quantity of ungulate nutritional resources by reverting stands to early successional stages. Additionally, timber harvest may allow for a more precise application of such effects, as managers choose where and how to harvest timber. However, the exact effects …

Quantifying Avian And Vegetation Communities On Agricultural Conservation Easement Wetlands In Eastern South Dakota, Katherine Millman

Electronic Theses and Dissertations

The Prairie Pothole Region of eastern South Dakota contains numerous small depressional wetlands, colloquially known as potholes, that provide important ecosystem services, including water storage, water quality improvement, and wildlife habitat. The Agricultural Conservation Easement Program (ACEP) was established by the U.S. Department of Agriculture to protect and restore wetlands and grasslands on private land through easements such as Wetland Reserve Easements. Although ACEP requires management practices intended to maintain or improve habitat quality, few studies have evaluated their effectiveness at supporting wildlife communities and vegetation integrity. To address this gap, we evaluated wetlands at 30 ACEP sites and 20 …

Balancing Timber Harvest And Biodiversity: Impacts Of Selective Logging On Wildlife In The Chiquibul Forest Reserve, Belize, Kilynn Groen

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Selective logging is often promoted as a sustainable forestry practice that maintains biodiversity and ecosystem function, yet its ecological consequences remain under examined, particularly in tropical forests. This study investigates how selective logging affects wildlife communities in the Chiquibul Forest Reserve, Belize. Using remote camera trap data from 22 sites (9 unlogged forest sites and 13 logged (stump) sites), we assessed species richness, trophic structure, and environmental predictors of wildlife abundance. While overall wildlife captures and species richness did not differ significantly between forest and stump habitats, principal component analysis revealed strong community-level separation, with stump habitats supporting distinct species …

Assessing Intra-Seasonal Changes In Summer Elk Diet Composition, Ava E. Window

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Elk (Cervus canadensis) require adequate forage to fulfill their seasonal nutritional requirements. Elk undergo their highest nutritional demands during summer to support critical life functions such as late gestation, lactation, and juvenile growth. However, variations in plant phenology significantly influence the quality and quantity of forage available to elk during the summer season. As summer advances and plant communities mature, forage quality often declines, leading to a landscape that imposes greater nutritional constraints on elk. As a result, prior research on elk foraging habits has primarily focused on late summer. This has led to limited knowledge surrounding the …

Sugar Maple (Acer Saccharum Marsh.) Tree-Ring Growth And Carbon Stable Isotope Responses To Nitrogen And Climate, Libbie Ring

Dissertations, Master's Theses and Master's Reports

This dendrochronological and stable carbon isotope study used tree rings from sugar maple (Acer Saccharum Marsh.) collected at long-term nitrogen (N) amended sites throughout Michigan to understand N amendment and deposition, climate, and growth relationships. Climate responses varied by site, however, we found importance in grouping sites by “productivity” which is related to inherent N and soil nutrients. Our results did not detect an overall effect of N amendments on growth during the treatment period. However, data shows N amendments benefiting larger diameter trees, while smaller diameter trees responded more positively without amendments, especially on more productive sites. Results …

Distribution And Ecology Of The Cedar Keys Mole Skink (Plestiodon Egregius Insularis), Kevin M. Enge, Louis A. Somma, Paul E. Moler, Travis M. Thomas, Matthew T. Fedler, John M. Matter, Dennis C. Haney

Papers in Herpetology

We conducted surveys for the Cedar Keys Mole Skink, Plestiodon egregius insularis (Mount), during 1989– 1999 and 2015–2024, examined museum vouchers, and compiled personal observations from others to determine the status and distribution of this subspecies, which has the smallest geographic distribution of the five subspecies and is being considered for federal listing. We observed Cedar Keys Mole Skinks on Airstrip Island, Atsena Otie, Cedar Point, Deer Island, North Key, Scale Key, Seahorse Key, Snake Key, and possibly Dog Island. We have anecdotal reports of Mole Skinks on Way Key, which contains the most potential habitat and is the main …

The Impacts Of Permafrost Thaw Slumps On Arctic Stream Ecology, Maria Dolan

Theses and Dissertations (Comprehensive)

Climate change is intensifying permafrost thaw across terrain of the circumpolar Arctic. Increased temperatures and rainfall at northern latitudes have resulted in the expansion of thermokarst features such as retrogressive thaw slumps, which make previously frozen debris available for transport into nearby river systems. In the Peel Plateau, Northwest Territories, the mobilization of these materials exposes rivers to a large quantity of sediment and solutes that may act as a chronic, press disturbance, potentially altering stream food webs. Here, I examine if: 1) thaw slumps have driven changes to the physical and biological properties of slump impacted streams since an …

Thermokarst Can Stimulate Tall Shrub Productivity And Plant-Soil Feedbacks In The Low-Arctic Tundra, Claire O'Brien

Theses and Dissertations (Comprehensive)

Warming temperatures are exacerbating permafrost thaw disturbances in the Arctic. Permafrost thaw disturbances are facilitating tall, deciduous shrub expansion. However, potential productivity differences between shrubs that colonize disturbed areas and those in undisturbed tundra remain understudied. More productive shrubs optimize for fast growth over leaf longevity, meaning they may produce more abundant and higher quality litter which could accelerate decomposition rates and lead to faster nutrient cycling. Faster nutrient cycling could create a positive feedback loop between shrubs and soil, maintaining greater ecosystem productivity. I measured in situ soil characteristics and physiological and structural shrub functional traits for green alder …

Macroinvertebrate Communities And Food Web Structure In Tundra Streams Are Shaped By Substrate Size And Beaver Impoundments, Mathew K. Mervyn

Theses and Dissertations (Comprehensive)

North American beavers (Castor Canadensis) are expanding their range into the Arctic tundra as climate change drives earlier ice and snowmelt, and increased shrub cover. As ecosystem engineers, beavers build dams that alter water chemistry by creating impoundments within streams, trapping sediment and organic matter, and modifying nutrient cycling. This thesis evaluates how beaver impoundments interact with natural geomorphic variation in tundra streams and how impoundments affect tundra freshwater ecosystems in the western Canadian Arctic.

In Chapter 2, I compared water chemistry and benthic macroinvertebrate (BMI) community composition across 16 stream reaches, including those with and without beaver dams, with …

High Temporal Resolution Gene Expression Analysis Of Acute Heat Stress Response In Acropora Cervicornis And Porites Astreoides, Katherine Parker, Nicolas Evensen, Iliana Baums, Daniel Barshis

Biological Sciences Faculty Publications

Widespread coral bleaching and mortality events are becoming increasingly frequent due to rising ocean temperatures, though certain coral species and populations have displayed higher tolerance to elevated emperatures than others. As such, it is of high research priority to identify thermally tolerant coral populations for research and conservation and assess the biological mechanisms allowing these populations to survive exposure to higher temperatures. This research utilized the Coral Bleaching Automated Stress System (CBASS), a portable experimental aquaria system with precise temperature manipulation, to assess the thermal thresholds and heat stress response of two coral species from Summerland Key, FL, USA. Seven …

Carbon Dynamics Across The Mangrove-Tidal Flat Ecotone In A Tropical Seascape, E. S. Yando, I. J.B. Alemu, L. Kiah Eng, T. M. Sloey, M. Van Breugel, Bhatia N. Friess

Biological Sciences Faculty Publications

Mangroves and other blue carbon ecosystems are important for climate through the storage and sequestration of carbon. Most research estimates carbon dynamics by subsampling central portions of the ecosystem and are then upscales using habitat maps to patch, landscape, or regional levels. However, heterogeneity is rarely accounted for - particularly at edges. Further, adjacent tidal flat ecosystems have only recently been considered for carbon storage, but may be undervalued if areas where they transition with vegetated systems are not accounted for. To address the lack of information at coastal ecotones, we examined both soil carbon storage and carbon dioxide flux …

Investigating The Relationships Between Biotic And Abiotic Factors Affecting Migratory Behavior In Westslope Cutthroat Trout Within The Pend Oreille System, Garrett M. Duncan

EWU Masters Thesis Collection

Salmonids express several different life histories from migrating to oceans and back or staying in their natal streams as a resident. Migratory individuals are a vital part of the overall success of populations due to the potential for increased genetic diversity and increased fecundity they offer over resident individuals. This research was completed in three basins including Priest River, Pack River, and Lightning Creek which are all connected to the Pend Oreille Basin and are important producers of Westslope Cutthroat Trout (Oncorhynchus clarkii lewisi). Thirty-nine sites were sampled between the three basins. Results were compared between these tributaries that have …

Helminth Parasites Of Galápagos Mammals: A New Cestode Of The Genus Raillietina From The Endemic Rice Rat Nesoryzomys Swarthi And A Summary Of Parasites From Both Endemic And Invasive Rodents, Scott Lyell Gardner, Emma K. Chesley, Michael C. Friedle, Altangerel Tsogtsaikhan Dursahinhan

Scott L. Gardner Publications

In this first report of endoparasites from endemic land-mammals of the Galápagos Islands, we describe a new species of cestode of the genus Raillietina (Cyclophyllidea: Davaineidae) from a species of Nesoryzomys and summarize the extent of helminth parasitism in both oryzomyine endemics and introduced species of Rattus. Up to the current time, no helminth parasites have been reported from rodents of the Galápagos, and little work has yet been done describing and synthesizing Galápagos parasite diversity. In historical times, several species of autochthonous rodents have occupied the islands including: Nesoryzomys narboroughi Heller 1904, N. fernandinae Hutterer and Hirsch …

Tailwater Trout Population Dynamics, Connor Dylan Cunningham

Graduate Theses/Dissertations

Dams have been constructed throughout the world and provide several resources for humans (e.g., flood control, hydropower). These structures heavily alter the upstream and downstream environment. One consequence of these alterations is the creation of “tailwaters”, which can create cold-water habitat via hypolimnetic releases. In the southeast United States these tailwater environments are often managed for the recreational use of nonnative salmonids. The unnatural flow regimes of tailwaters affect the biotic and abiotic conditions and ultimately the dynamic rate functions (i.e., recruitment, growth, mortality) of the fish inhabiting them. As such, the goal of this research is to provide fisheries …