Population Biology Commons^™

From Genes To Streams: Mitochondrial Approaches To Population Monitoring Of The Santa Ana Sucker Catostomus Santaanae, Mariana Antonio

Electronic Theses, Projects, and Dissertations

This study was developed to use aquatic environmental DNA (eDNA) as a tool to detect the presence of the Santa Ana sucker (Catostomus santaanae), a federally threatened fish species, across the Santa Ana River in Southern California. Environmental DNA is any genetic material that an organism sheds into the environment. We can get an idea of what aquatic species are present when sampling water at a given site. We sequenced the complete mitochondrial genome (mitogenome) of the Santa Ana sucker and designed custom DNA primers to improve eDNA detection accuracy. These primers were selected based on high genetic …

History And Distribution Of The Dark Ibises (Glossy Ibis Plegadis Falcinellus And White-Faced Ibis P. Chihi) In Arkansas, R. Tumlison, P. D. Rodriguez

Journal of the Arkansas Academy of Science

The Glossy Ibis (Plegadis falcinellus) and White-faced Ibis (P. chihi) sometimes are reported simply as Dark Ibises due to difficulty in identifying them when mature characters are not clearly visible. We evaluated reports verified on citizen science websites to examine the origins and distributions of these migratory species in Arkansas. The Glossy Ibis was first documented in Arkansas in 1956, has been reported in 21 of our 75 counties, and is found more commonly in eastern Arkansas. The White-faced Ibis was first reported in Arkansas in 1971, has been reported in 41 of our 75 counties, …

Morphological Variation Of Lingual Glands In Wild American Alligator (Alligator Mississippiensis) Populations, Benjamin Angalet

Master's Theses

American alligators (Alligator mississippiensis) inhabit diverse aquatic ecosystems including freshwater wetlands, swamps, and estuarine rivers. As apex predators, their physiological resilience has implications for ecosystem stability and long-term conservation. With projected sea-level rise and increasing saltwater intrusion into coastal freshwater habitats, understanding the osmoregulatory capacity of alligators is increasingly important. Unlike marine-tolerant crocodilians such as the saltwater crocodile (Crocodylus porosus), which possess specialized salt-secreting lingual glands in addition to renal and cloacal mechanisms, the morphology and physiological significance of lingual glands in wild American alligators remain poorly understood. This study examined lingual gland morphology and plasma …

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 …

Skin Pattern As A Potential Monitoring Tool For Frog Populations, Lídize Sagarnaga Rivera, Virginie Rolland Dr., Lorin Neuman-Lee Dr.

Create@State

Skin pattern as a potential monitoring tool for frog populations

Population monitoring, which requires identifying individuals, is crucial for species conservation. Common techniques involve marking, which can harm animals and alter their behaviors. Natural markings are an alternative not yet explored for amphibians. Yet, the traditional method with elastomers (fluorescent implants) is invasive and not completely reliable—the tag may become lost or hard to see. The American green tree frog (Dryophytes cinereus) possesses naturally occurring and distinct golden dots on their dorsal side.  Therefore, we aim to assess whether patterns of golden dots on the skin of green …

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 …

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 …

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 …

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 …

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 …

Relationship Between Ratio Of Hybrid Sunfish To Their Parent Species And Latitude, Maxwell Kattner

Journal of Earth and Life Science

Hybrid sunfish of the Lepomis genus make up a generally small but notable portion of the population of sunfish in Minnesota lakes. Hybrid sunfish play a significant role in freshwater ecosystems across the United States. They are both morphologically and behaviorally distinct in some ways and similar in other ways to their parent species, causing them to both fill and compete with their parent species for niches occupied by multiple Lepomis species. Despite this, the ratio of hybrid sunfish to their parent species has never been properly explored. This study observed if the ratio of hybrid sunfish to their parent …

Geographic Variation In Proteomic Responses To Ocean Acidification In A Cold-Water Coral (Balanophyllia Elegans), Keana A. Richmond

Cal Poly Humboldt theses and projects

In the face of a rapidly changing climate, assessing organismal responses to future stressors in the context of current, natural exposure to stress could provide key insights to understanding marine ecosystem resilience. I used Balanophyllia elegans, a cold-water, solitary, azooxanthellate coral as a model to better understand how varying oceanographic conditions across its geographic range have shaped its ability to tolerate and potentially adapt to current and future ocean acidification conditions. I collected B. elegans individuals from four sites across 2,500km of their range and subjected them to two pH treatments to investigate site-specific protein expression in response to …

Current And Historical Occurrences Of Rare Coastal Plants In The Hampton Falls Salt Marshes, Liliana T. Chirichella

Honors Theses and Capstones

A botanical survey of two sites in the Hampton Falls saltmarshes was conducted to document the occurrences of a list of eleven endangered and threatened coastal plants listed in the Natural Heritage Bureau’s NH Rare Plant List. This survey was conducted in fulfillment of the NH Native Plant Protection Act to highlight and identify target species in an area where restorative runneling is to be implemented in order to restore proper hydrology and prevent further expansion of mega-pools in the Little River and Depot Road salt marsh sites, which have been subject to historical ditching and are a part of …

Using Camera-Based Unmarked Spatial Capture-Recapture Modeling To Estimate Reintroduced Elk (Cervus Canadensis) Population Parameters And Distribution In Southeastern Kentucky, Claire Marie Muia

Theses and Dissertations--Forestry and Natural Resources

Estimation of population parameters is important for wildlife management decisions. Elk reintroduced to southeastern Kentucky experienced early irruptive population growth and are currently monitored using a statewide harvest-based statistical population reconstruction model (SPR) across the Kentucky Elk Restoration Zone (KERZ). Because the SPR model is spatially coarse and difficult to scale to the smaller management units comprising the KERZ, we conducted a spatially explicit capture-recapture study using a clustered camera-trapping array deployed for 10 weeks from June–August 2024 to estimate elk population parameters within Management Unit 4. Due to a lack of resights of GPS-marked elk, population parameters were estimated …

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- …

Size Structure Comparison Of Bluegill In Lakes With And Without Special Regulations, Jenna Lawin

Journal of Earth and Life Science

Lots of individuals have mixed feelings about special regulations for all sorts of game fish species such as northern pike Esox lucius, crappie Pomoxis spp., sunfish Lepomis spp., and so on. One species commonly sought after by many is bluegill Lepomis macrochirus. Bluegill are often deemed easy to find, catch, and clean. This study looks at three different categories of lakes (all lakes contain bluegill populations). The three categories are lakes with a five sunfish limit, lakes with a ten sunfish limit, and lakes without any special regulations. This study provides valuable insight into the size …

Phylogeography, Fungal Host Specificity, And Fitness In The Corallorhiza Maculata Species Complex, Hana Thixton-Nolan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Mycoheterotrophic plants exploit fungi for most or all nutritional needs, providing a compelling system to address the evolutionary consequences of genome reduction, population-level variation, and germination requirements. I am using the widespread Corallorhiza maculata species complex to address questions of genomic variation, fungal host specificity, morphological variation, and germination requirements across the broad geographic range from Mexico to northern North America. This complex contains C. bulbosa, C. macrantha, and C. mertensiana, the latter with three varieties (maculata, occidentalis, and mexicana). These taxa vary in flowering time, floral morphology, and fungal associations. However, the degree …

An Ecological-Evolutionary Investigation Of Phenotypic, Genetic, And Environmental Variation And Correlations Among Reproductive Traits Of Tall Goldenrod (Solidago Altissima), Michael J. Wise, Daniel Lavy, David E. Carr, Warren G. Abrahamson Ii

Faculty Journal Articles

Although fitness-related traits are expected to be under strong selection, traits related to reproduction are often quite variable within plant populations. We used data from two large greenhouse experiments to quantify phenotypic, genetic, and environmental variation, as well as genetic tradeoffs that might help explain the maintenance of withinpopulation variation in four traits related to sexual or vegetative reproduction in tall goldenrod (Solidago altissima). The goldenrod population exhibited high levels of both phenotypic and genetic variation for capitulum (flower head) number and size, seed production, and rhizome growth. Significant negative genetic correlations were present between the number of capitula and …

A Re-Evaluation Of Atlantic Bluefin Tuna (Thunnus Thynnus) Spawning Distribution In The Western Atlantic Ocean, David E. Richardson, Katrin E. Marancik, Malgorzata Adamus, Elizabeth A. Broughton, Robert K. Cowen, Trika Gerard, Christina M. Hernández, John J. Hoey, Joel K. Llopiz, Molly E. Lutcavage, Estrella Malca, Debra L. Palka, Lourdes Vásquez-Yeomans, Harvey J. Walsh, C. Michelle Willis, Glenn A. Zapfe

Biological Sciences Faculty Publications

There is currently a lack of consensus on the spatial, seasonal and decadal-scale patterns of Atlantic bluefin tuna (Thunnus thynnus) spawning in the western Atlantic Ocean. We compiled ichthyoplankton and reproductive data to characterize bluefin spawning patterns and the uncertainty in these patterns. Ichthyoplankton data indicates that bluefin spawn in the Gulf of America/Gulf of Mexico, northwest Caribbean Sea, north of the Bahamas, along the inshore edge of the Florida Current off the Carolinas and in the western Slope Sea. Reproductive studies identified these same spawning areas, as well as the Windward Passage and waters east of the …

Hybridization And Introgression In Marine Invertebrates: Population Genomics Of Phymactis Papillosa And Asterias Sea Stars, Christopher J. Dookie

Dissertations and Theses

Hybridization and introgression are evolutionary significant processes in marine invertebrates (Sanford & Kelly,2011) yet genome-wide investigations of gene flow in these taxa remain limited relative to vertebrate systems (Marchi et al., 2021). This thesis presents genomic analyses of hybridization and introgression in two marine invertebrates occupying contrasting oceanographic settings and characterized by contrasting genomic datasets: restriction-site associated DNA sequencing (RADseq) SNP data for the eastern Pacific sea anemone Phymactis papillosa and whole genome sequencing (WGS) data for the North Atlantic sea stars Asterias rubens and Asterias forbesi. For each system, I applied coalescent-based species tree inference using CASTER (Zhang …

A Review Of Mockingbird Song, Jacqueline Milander

Student Theses

The northern mockingbird (Mimus polyglottos) is known for its large repertoire and highly versatile song patterns.  It is a frequent mimic that is thought to continue learning sounds from its environment for the duration of its life.  Utilizing available song studies, this is a comprehensive review of northern mockingbird song, including learning, mimicry, repertoires, song dependence on seasonal cyclicity, and song function, particularly interspecific territoriality. While much discussion has surrounded the idea that northern mockingbirds engage in interspecific territoriality and that vocal mimicry functions in intersexual selection, this review provides new insight into the possibility that latitudinal differences among populations …

Population Genomics And Evolution Of Pseudomonas Aeruginosa, Samara T. Choudhury

Electronic Theses & Dissertations (2024 - present)

Pseudomonas aeruginosa is a Gram-negative bacterium ubiquitous in diverse environments and an opportunistic pathogen in humans. It is a leading cause of chronic lung infections in cystic fibrosis patients and of hospital-acquired pneumonia and sepsis. With a large flexible genome and abundant mobile genetic elements, P. aeruginosa exhibits high levels of antimicrobial resistance (AMR), making it a significant public health threat. Evolutionary processes such as homologous recombination, and horizontal gene transfer generate extensive genomic diversity in this species and facilitate the spread of resistance genes. In this dissertation, I investigate the genetic and evolutionary factors shaping P. aeruginosa population structure …

Population Structure Analysis Of Four Basal Higher-Attines Using Bioinformatic Approaches, Gabriel Mcdanield

Biology Theses

Metapopulations within the family Formicidae are unique among other animals due to the large colonies they build, and the mating strategies required to fertilize a specialized reproductive caste that will often produce young for the life of the colony. One group of ants, the fungus-gardeners (tribe Attini). The population structure of North American non-leafcutting, fungus-gardening ants has been understudied, especially in the southwest of the United States. Additionally, not much is known about their dispersal biology, so the dynamics of dispersal of these species and how they affect population structure is likewise not well known. To shed light on the …

The Micro-Communities Of Trees, Nicholas Davis, Lily Boysworth, Westen Wilburn

Fall Showcase for Research and Creative Inquiry

This study investigated how tree species diversity influences the variety of organisms living on or around trees across different habitat types. Field data were collected through random tree selection, measurement of tree diameter, identification of species, and estimation of surrounding ground cover types such as grass, herbaceous plants, woody plants, and leaf litter. Biodiversity associated with each tree was analyzed using the Shannon Diversity Index across several ecosystems, including grassland, woodland, and pond environments. Results indicated that the pond ecosystem exhibited the highest species diversity, followed by woodlands and then forests. A range of organisms, including lichens, mites, fungi, and …

Montserrat Developments Impacting Local Coral Reefs, Emma I. Bartholomew

2025 Symposium

Montserrat is a small island in the Caribbean, and over half of the island is in the exclusion zone because of the active volcano, Soufrière Hills. In that half was the old capital, Plymouth, which has since been abandoned, and its old port. The old port was getting less reliable and accessible, so they decided to build a new port in Little Bay, closer to the seat of government in Brades. This study explored how the addition of the new port impacted the corals in that area. We explored several different bays and recorded the diversity and health of the …

Nitrogen Addition Additively Boosts Climate-Driven Salsola Tragus (Russian Thistle) Invasion Into Southwestern Usa Grasslands, Melissa A. Bacigalupa

Biology ETDs

Effective management of invasive, non-native plants requires understanding key drivers of invasion, including nitrogen enrichment from atmospheric deposition and agriculture. Long-term studies are essential for capturing complex invasion dynamics yet remain uncommon. We used 22 years of observations and 14 years of nitrogen experiments to examine invasion by Salsola tragus (Russian thistle) into three semi-arid grasslands of central New Mexico. Invasion patterns varied, with rapid expansion in Chihuahuan Desert grassland and the Desert-Plains ecotone but stability in Plains grassland. Under ambient nitrogen, precipitation most strongly correlated with Russian thistle biomass and high native grass biomass was associated with Russian thistle …

Occupancy Sampling To Examine Spatial Distribution Of Oklahoma Salamanders (Eurycea Tynerensis) Among Headwater Streams In The Ozark Highlands, Sophia Anreder

Biological Sciences Undergraduate Honors Theses

Water conditions are changing globally due to climate change (Gleick, 1989). Headwater streams specifically are vulnerable to changes in hydrology, water quality, and physical characteristics from anthropogenic practices due to their small watersheds with shallow soils, yet they are often not a priority in conservation (Campbell et al., 2011; Abell et al., 2017). Within streams, plethodontid (i.e., lungless) salamanders, which are also sensitive to environmental changes, may be restricted in their distribution due to undefined stream characteristics and predation by fish (Welsh and Droege, 2002; Kuhajda et al., 2015). To better understand the pressures that influence stream salamander occupancy, I …

Pollinator Plant Communities Within Restored Montane Longleaf Pine Ecosystems, Hanen Van Rossem

Master's Theses

Historically the fire-dependent and biodiverse longleaf pine (Pinus palustris) ecosystem was the dominant ecosystem of the Southeastern US. This ecosystem’s range was massively reduced due to land conversion and fire exclusion, causing the decline of many native species. Efforts to restore and protect longleaf pine stands are now ongoing with the goal of expanding habitat and refuge for threatened species. Differences in restoration practices and prior land use may influence the extent to which restored habitat patches can support pollinators and their plants. This study compared pollinator plant biodiversity between restored neighboring montane longleaf pine stands that differed in …

Balancing Burrowing Owl (Athene Cunicularia Hypugaea) Protections While Maintaining Renewable Energy Development Within The San Joaquin Valley, Madison Lenzi Mcginn

Master's Projects and Capstones

Balancing the needs of wildlife and people has long been a complex challenge. The San Joaquin Valley exemplifies this tension, as space for agriculture and urbanization compete for land use of native grasslands– often resulting in the conversion of grasslands for agriculture fields, commercialized areas, or energy development. With an increasing number of agricultural landscapes going fallow and the passing of SB-100 in 2018, solar farm development has emerged as an attractive option to offset financial losses from unproductive farmland. However, the same landscapes favored for solar development also provide suitable habitat for sensitive species such the western burrowing owl …