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Remove To Recruit: The Short-Term Efficacy Of Invasive Shrub Removal In A Minnesota Floodplain Forest, Claire S. Wiley

Biology Honors Projects

Within Midwest floodplain forests, there is a lack of long-term studies focusing on native tree recruitment post invasive shrub removal. With interacting threats such as emerald ash borer (Agrilus planipennis), invasive earthworms, and white-tailed deer (Odocoileus virginianus), land managers need particular information about these ecosystems in order to better understand how to protect them. This study aims to explore the efficacy of the removal of Rhamnus cathartica and Lonicera spp. in promoting native tree recruitment within a Minnesota floodplain forest along the Mississippi River. Results revealed that post removal ash (Fraxinus spp.) seedling abundance …

Does Social Grouping Influence Object Play By Belugas?, Javier Obiltas, Phillip Clayton

Posters - 2026

Play is defined as voluntary behavior that differs from functional behaviors and typically occurs in low-stress environments. In cetaceans, object play has been linked to development, motor skill practice, and social learning. Play behavior is an important factor of development in belugas, because belugas are social animals that live and interact within groups, the composition of these groups or "groupings" might influence their play behaviors. Understanding how said groupings may affect the play rates may help researchers better understand the development of behavior and social dynamics of the beluga groupings. The purpose of this study was to see whether grouping …

Does Shape Matter?: How Salamander Head Morphology Shifts Based On Environment, Caitlyn Pinaga, Naomi Ramirez, Sonia Cerrillo

Posters - 2026

Groundwater salamanders of the genus Eurycea represent a diverse group of amphibians inhabiting the aquifer systems of central Texas, where both surface-dwelling and fully subterranean species coexist. Subterranean habitats impose extreme selective pressures, including complete darkness, limited nutrient availability, and stable environmental conditions, which drive convergent morphological traits such as eye reduction or loss, decreased pigmentation, and elongation of appendages. A key evolutionary pattern seen in these systems is sensory compensation, in which the reduction of one sensory modality, in this case vision, is accompanied by the enhancement of others. In aquatic salamanders, this often involves expansion of the lateral …

Smell Over Sight: Determining Levels Of Olfactory Gene Expression Between Surface And Subterranean Eurycea Salamanders, Sonia Cerrillo, Iliana Melendez, Naomi Ramirez

Posters - 2026

In the karst aquifers of central Texas, including the Edwards and Trinity systems, organisms live in an environment defined by constant temperatures, total darkness, and scarce food resources. These conditions have driven the evolution of salamanders in the genus Eurycea, particularly those that have adapted to subterranean life. Cave-dwelling species like Eurycea rathbuni exhibit hallmark “blind salamander” traits, including educed eyes, loss of pigmentation, and flattened head morphology. In contrast, surface-dwelling relatives such as Eurycea nana and Eurycea sosorum retain fully developed eyes and pigmentation, while some species like Eurycea latitans display both surface and subterranean forms across different populations.

Teeth That Tell Time: Elemental Analysis From Shark Teeth, Gisele-Elizabeth Perez, David Turner

Research Papers

Sharks (Chondrichthyes) have hunted in the oceans for over 400 million years, their teeth leaving history behind, constantly becoming a part of the fossilization process (Worm et al. 2013). Their survival throughout 5 major extinctions is due to their ability to adapt easily with slow metabolism, a wide range of diet, and an efficient physiology. Shark teeth are vital to the hunting and consumption of their prey, making it a point for scientists to study them. Their tooth minerals contain fluorapatite in their enameloid, and dentin in the “root” of the tooth, with extinct species containing dentin and hydroxyapatite in …

Testing The Intermediate Disturbance Hypothesis On Anthropogenic Pressure In Central Alabama, Gavin Terrell

Theses

Biodiversity is fundamental to maintaining ecosystem structure and function globally. Prior to the late 20th century, ecological theory generally predicted that biodiversity would be highest in systems experiencing minimal disturbance. However, Joseph H. Connell challenged this view with the Intermediate Disturbance Hypothesis (IDH), which posits that species diversity peaks at intermediate levels of disturbance and declines under conditions of both low and high disturbance. Although widely cited, the applicability of the IDH to natural systems remains debated, particularly in the context of anthropogenic disturbances and when diversity is measured beyond species richness alone.

This study evaluated the predictions of the …

Fisheries Management Paper No.312: Discussion Paper On Management And Licensing Options For The Charter Industry - Statewide Strategic Review Of Western Australia’S Charter Fishing Sector, Department Of Primary Industries And Regional Development, Western Australia

Fisheries Management Papers

This consultation paper has been prepared to support the statewide strategic review of Western Australia’s (WA) charter fishing sector, which was initiated as a government commitment.

The paper details issues and proposals relating to the management and licensing framework, development opportunities and representation model for the charter fishing industry. The proposals have been developed in consultation with the Charter Review Working Group. The Department of Primary Industries and Regional Development (DPIRD) now seeks comment from relevant stakeholders on the issues and proposals outlined within this paper.

Comments provided will assist in providing advice and recommendations to the Minister for Fisheries …

Developing A Range Prediction For The Imperiled Florida Harvester Ant (Pogonomyrmex Badius) Using Species Distribution Modeling, Noah Williamson

Honors Theses

The Florida Harvester Ant (Pogonomyrmex badius) was once widespread and commonplace throughout the sandhills of the Southeastern United States, providing key ecosystem services, such as seed dispersal and soil aeration. Over recent decades, however, Florida Harvester Ant populations have declined in some areas. Current literature postulates that Red Imported Fire Ants (RIFA), and the insecticides used to manage them, as well as further human encroachment onto their habitat, all likely contributed to Florida Harvester Ant population declines. Thus, to better protect these organisms, pursue data-driven conservation efforts, and guide management practices, more information about their nest site selection, as well …

The Missing Lynx: Investigating Passive And Active Rewilding With The Eurasian Lynx, Isaiah Charles, Tatiana Flores, Isabella Lopez

Conservation Biology

The Eurasian Lynx (Lynx lynx) is a wild cat native to the boreal forests, mountains and grasslands of Europe and Asia (Bhattacharyya, 2025). The Eurasian lynx keep ungulate populations in check which allow for forests to recover from overgrazing, promoting biodiversity and ecological balance. However, the Eurasian lynx had become locally extinct across Europe by the 1900s due to habitat loss, hunting by farmers in retaliation for predation of livestock and the illegal fur trade. Conservation and ecological restoration efforts to rebuild the lynx population have been underway. Rewilding is a form of ecological restoration involving the reintroduction of a …

Analysis Of Mitochondrial Dna Haplotype Groups For South Texas Canids, Canis Rufus, After Past Hybridization Events, Isabella Lopez

Presentations - 2026

mtDNA: mitochondrial DNA; passed from maternal parent to offspring (Haplotype)

Haplotype:  a group of genes or genetic markers inherited together from a single parent (Haplotype)

Mitochondrial DNA haplotypes specific sequences of mtDNA that is passed exclusively from maternal parent to offspring (Giles et al. 1980)

Pro's:

It is passed unchanged from mother to offspring, meaning it is fairly stable (Giles et al. 1980)

Each cell has multiple mitochondria vs one nucleus , which means mtDNA it is more likely to be recoverable from degraded samples like scat (Templeton et al. 2013)

Microplastic-Mediated Delivery Of Di-Butyl Phthalate Alters C. Elegans Lifespan And Reproductive Fidelity, Chiara Angelyn Maldonado

Presentations - 2026

•The challenge: microplastic contamination •The question: How do microplastics and chemical contaminants affect living organisms? •The follow-up: What’s next!

Raptor Abundance And Occupancy In Urban Parks Within Metropolitan Landscapes, Mary- Esther Leblanc

Posters - 2026

Rapid urbanization is one of the most significant and accelerating drivers of global biodiversity change, reshaping wildlife communities by fragmenting habitat, altering prey availability, and introducing human disturbances. Despite these pressures, some wildlife species are attracted to and may even flourish in urban settings, primarily because urbanization creates an altered landscape that often unintentionally provides resources functioning as components of habitat. (Chiron et al., 2024) Raptors, as apex predators within avian food webs, offer a valuable lens through which to examine these dynamics. While raptor communities are broadly negatively impacted by urbanization, some species can thrive in urban areas. (Leveau …

Mapping Sensory Landscapes: Distribution And Arrangement Of The Anterior Lateral Line System In Texas Catfish, Tatiana K. Flores, Ruben Tovar

Posters - 2026

Fish have a system of sensory organs known as the lateral line system. This system contains numerous mechanoreceptive neuromasts and electroreceptive ampullary organs (Northcutt et al, 2000). Neuromasts are small, hair-like structures located within canals in the lateral line system just under the fish’s skin and are open to the environment through small pores visible on its skin (Parker, 2025). Water flows into these canals through the pores which stimulates the sensitive hair cells, resulting in electrical signals sent to the fish’s brain. The brain interprets these signals and creates “images” of the fish’s surroundings, helping it to see even …

Does Habitat Predict Head Shape? A Comparative Geometric Morphometric Analysis Of Eurycea Spp., Sarah Flores-Garza, Alexa Miner, Gianna Montelongo

Posters - 2026

Subterranean environments impose strong selective pressures, including complete darkness and reliance on non-visual sensory systems. In Eurycea salamanders, these conditions are associated with traits such as reduced eyes and expanded head regions that improve sensory detection (Tovar et al., 2025). Subterranean species are often expected to share similar head shapes due to convergent evolution. However, not all species experience these pressures equally. Eurycea latitans is a polymorphic species that inhabits both surface and cave environments. Eurycea sp._NB is an obligate subterranean species, while Eurcyea sosorum is a surface species. This study tests whether habitat predicts head shape in Eurycea, or …

Teeth That Tell Time: Elemental Analysis From Shark Teeth, Gisele-Elizabeth Perez

Posters - 2026

Sharks (Chondrichthyes) have hunted in the oceans for over 400 million years, their teeth leaving history behind, constantly becoming a part of the fossilization process (Worm et al. 2013). Their survival throughout 5 major extinctions is due to their ability to adapt easily with slow metabolism, a wide range of diet, and an efficient physiology. Shark teeth are vital to the hunting and consumption of their prey, making it a point for scientists to study them. Their tooth minerals contain fluorapatite in their enameloid, and dentin in the “root” of the tooth, with extinct species containing dentin and hydroxyapatite in …

Bird Population Response To Abiotic And Biotic Stresses In Urban & Restored Oak Savannah Habitat, Annabelle Ball

Posters - 2026

Birds are heavily impacted by urban development. Many experience habitat fragmentation and removal of food sources. However, other species can adapt to and even thrive in urban environments, thanks to certain tree species, bird feeders, and buildings. In North America, the house sparrow and the European starling are invasive species that benefit from urban environments (Bartelt, 2011; Fitzwater, 2014). Meanwhile, many habitats across the continent are experiencing restoration/rewilding efforts for the benefit of birds. One such habitat is the oak-savannah, which is characterized by 10-30% canopy cover and a mixture of prairie & woodland vegetation, supporting a high diversity of …

Saved From The Brink Of Collapse: Evaluating The Success Of The Sussex Kelp Recovery Project, Keagan Farrell, Kelly Swyers, Adan Vasquez

Posters - 2026

Kelp forests are vital to ocean health, they provide habitat, food, and nursery grounds for a variety of marine species. These forests support fisheries, improve water quality, and help to protect coastlines (Eger et al. 2024). The Sussex Kelp Recovery Project is a marine conservation effort aimed at restoring their kelp forests along the Sussex coastline in southern England. This area lost up to 96% of its forests mainly due to the fishing practice trawling. Trawling is used to gather large amounts of fish, while dragging a net at the seafloor (Our history 2026). The main goal of the Sussex …

The Effects Human Presence Has On Dolphins Within A Natural Lagoon Enclosure In Managed Care, Mario Martinez, Winter Saldaña

Posters - 2026

● Previous research looked into the overall behavior of dolphins in managed care using observations of location (Dudzinski & Hill, 2025).

● This study provides opportunities to investigate the effects of human presence on dolphin activity and space use (Lauderdale et al., 2022; Trone et al., 2005).

● Purpose - To determine if human presence affects dolphin behavior / spatial use of natural lagoon.

● H1: Dolphin clustering will be seen in the most Northern part of the lagoon and area associated with humans consistently (Melillo et al., 2009).

● H2: Higher activity levels will be observed during the “during” …

Factors Influencing Sex-Based Movement Patterns In The Banded Garden Spider, Argiope Trifasciata (Forskal, 1776), Brandon R. Marrone

School of Biological Sciences: Dissertations, Theses, and Student Research

Movement is a fundamental ecological process shaping how individuals acquire mates, secure resources, and navigate heterogeneous landscapes. In species with extreme sexual size dimorphism (eSSD), such as the orb‑weaving spider Argiope trifasciata, males and females are predicted to experience different movement pressures driven by their reproductive roles. This thesis examines how individual traits and environmental conditions jointly influence movement across both sexes. Across two field seasons, we used intensive mark–recapture methods to quantify natural movement patterns of males and females within mapped prairie plots. The first chapter tested long‑standing predictions gravity hypothesis, which posits that smaller males benefit from …

Enhancing Urban Garden Capacity By Linking Biodiversity And Ecosystem Function, Mary T. Nguyen, Carleen Rauh, Shelby Gresch, Charlotte Correiro, Heidi Elmendorf, Adriane Fugh-Berman, Gina Wimp, Alexandra L. Decandia

Virginia Journal of Science

Urban agriculture broadly describes food and plant cultivation in metropolitan areas. While biodiversity is thought to support ecosystem health and resilience, the relationship between above-ground and below-ground diversity has been understudied in urban green spaces. This study examines plant, animal, bacterial, and fungal diversity across three distinct urban habitats: a turf lawn, a forb garden, and a farming space. Using bacterial 16S rRNA and fungal ITS2 sequencing, soil nutrient analyses, and surveys of vegetation and wildlife, we connect diverse philosophies in urban agriculture to their role in advancing community diversity and ecosystem function. We found that different urban gardens support …

Alabama Prairie Reconstruction: Comparing Management Pathways For A Southeastern Landscape, Cecelia R. Geyer

Theses

Southeastern prairies are highly biodiverse yet increasingly threatened by land-use change, fire suppression, and habitat fragmentation. These disturbance-dependent systems rely on periodic fire and grazing to maintain plant diversity and ecosystem function. This study evaluates prairie restoration strategies by testing predictions from the Intermediate Disturbance Hypothesis and the Patch Mosaic Burn Hypothesis. The study site was divided into three treatments: prescribed burned only (B), prescribed burned with mowing (BM) to simulate grazing, and an undisturbed control (C). A standardized mix of native plant seeds was broadcast across all treatments. Ecosystem health and function were evaluated using plant community diversity and …

Ecological Studies Of Wolves On Isle Royale, Sarah R. Hoy, Rolf O. Peterson, John A. Vucetich

Ecological Studies of Wolves on Isle Royale

Annual Report 2025-2026

Evaluating The Environmental Parameters Impacting Spawning Movement Of Gulf Sturgeon (Acipenser Desotoi) In The Bouie River System., Olivia St. Germain

Honors Theses

The anadromous Gulf Sturgeon (Acipenser desotoi) is federally listed as “threatened” and is natal to seven rivers from Louisiana to Florida. Only one spawning reach for Gulf Sturgeon natal to the Pascagoula River has been verified via the collection of eggs and larvae; a reach of the lower Bouie River. This reach is anthropogenically modified by four gravel mining formations, hereafter referred to as pits. The greater depths associated with this area have prompted previous researchers to suggest that Gulf Sturgeon may over-summer in pit formations instead of migrating to downstream holding areas in the Pascagoula River after spawning. The …

Comparing Head Shape Of Polymorphic Subterranean E. Latitans And Subterranean E. Sp. 4, Brandon Chapa, Jordan Cosgrove, Lizzeth Holguin

Posters - 2026

Eurycea latitans (E. latitans) from Honey Creek Cave and unnamed Eurycea species from New Braunfels, Texas (E. sp. 4) are two paedomorphic subterranean species. E. latitans is polymorphic, meaning it also exists as a surface species. Similarities in morphology of subterranean salamander species may be due to convergent evolution as a result of living in similar environments. These similarities include having flatter, wider heads, and wider mouths than surface species (Tovar et al. 2025). Variation may also exist among different subterranean salamander species. Texas Eurycea salamanders display “complex patterns of morphological divergence”, suggesting that isolation and local environmental pressures can …

The Missing Lynx: Ivestigating Passive And Active Rewilding With The Eurasian Lynx, Isaiah Charles, Tatiana Flores, Isabella Lopez

Posters - 2026

The Eurasian Lynx (Lynx lynx) is a wild cat native to the boreal forests, mountains and grasslands of Europe and Asia (Bhattacharyya, 2025). The Eurasian lynx keep ungulate populations in check which allow for forests to recover from overgrazing, promoting biodiversity and ecological balance. However, the Eurasian lynx had become locally extinct across Europe by the 1900s due to habitat loss, hunting by farmers in retaliation for predation of livestock and the illegal fur trade. Conservation and ecological restoration efforts to rebuild the lynx population have been underway. Rewilding is a form of ecological restoration involving the reintroduction of a …

Comparing Gngt1 Expression In Eye Tissue Of Polymorphic Salamander Species Through Development, Fiona Coulbourne, Camila Cardozo, Macarena Machado, Ruben Tovar

Posters - 2026

The effect of the environment on organisms and their adaptations is widely studied. When exposed to different environmental niches, phenotypic adaptation is observed even within species. Animals that live in dark cave environments show a loss of their eyesight, since this sense is no longer useful to keep. Previous research has studied salamanders of the clade Eurycea and compared gene expression to subterranean and surface phenotypes1. E.pterophila is observed to express these two phenotypes depending on its environment, either Preserve Cave (subterranean) or Comal Springs (surface). Subterranean variant shows reduced eye volume and assumes to have decreased eyesight. Utilizing RNASeq …

Beluga Buddies: The Preferred Social Network Of Belugas In Managed Care, Valery Marinelarena, Diamond Garcia

Posters - 2026

Belugas societies are not fixed  and group composition is everchanging. Group composition can also influence behavior. This study aims to examine the preferred social networks and the role age plays in the behavioral diversity within a group of managed care belugas housed at Sea World San Antonio. Results Supported TYO had a preferred, non-random social network and ATL performing more chinslaps than TYO.

Assessing Differential Expression In Skin Of Surface Versus Subterranean Salamanders (Eurycea) Through Development, Chiara Angelyn Maldonado, Van Nguyen, Amy Torres

Posters - 2026

In salamanders, previous findings have shown that subterranean environments impose different selection pressures on sensory systems than surface environments do (1). Differences in ocular development between phenotypes is part of ongoing research to better understand the evolutionary and molecular underpinnings. Studies have shown that parallel ocular development occurred in subterranean and surface phenotypes, while pax6 expression decreased in latter stages of development of subterranean species (2). These insights of gene labeling and expression as well as reduction of ocular structures in latter stages of development provide a stage for understanding evolutionary processes and genetic mechanisms as well as having potential …

Emerald Bowfin Amia Ocellicauda Ecology In Three Minnesota Lakes: Abundance, Age Analysis, Diet Composition, And Stable Isotope Food Web, Griffin Blegen

Biology Graduate Theses

The Emerald Bowfin Amia ocellicauda is a predatory fish species native to Minnesota that has often been discriminated against. This research expands ecological knowledge of Bowfin in Minnesota and provides population data to guide future management. Bowfin were sampled in the spring of 2024 and 2025 and a multi-census mark–recapture model was used to estimate abundance in three lakes. Estimated populations were 196 individuals in Little Toad Lake (95% CI: 116, 242) or 4.4 fish/littoral ha (95% CI: 2.7,5.7), 657 in Lake Sarah (95% CI: 436, 1014) or 4.2 fish/littoral ha (95% CI: 3.0, 6.7), and 612 in Gun Lake …

Variable Hybridization Rates Between F2 Fundulus Notatus Females, Jordan Tanaka

Honors Theses

Hybridization between two related species has been widely observed and offers a lens into complex evolutionary processes. Endogenous and exogenous factors affect hybrid fitness and diversification, and pre-zygotic and post-zygotic barriers affect species’ ability to hybridize. Female mate choice is a pre-zygotic isolation mechanism which is known to be more significant than male mate choice in many species, a trend which is linked to females often investing more energy into offspring. Detailing the ways in which these mechanisms operate is integral to understanding hybridization on a larger scale. The species examined here, Fundulus notatus and Fundulus olivaceous, are closely …