Ecology and Evolutionary Biology Commons^™

Assessing Climate-Driven Shifts In Floral Resource Availability For Bees On Barrier Islands In The Southeastern U.S., Hannah Brown

College of Graduate Studies: Theses & Dissertations

Climate change can alter the timing of bee and angiosperm phenology, potentially reshaping the seasonal availability of floral resources for bee species. Although plant-pollinator phenology has been widely studied in temperate systems, less is known about these dynamics in subtropical coastal ecosystems, such as barrier islands in the southeastern United States. In this study, we examined climate-driven changes in bee activity and floral resource availability across 16 barrier-island sites spanning from Florida to Virginia. Using museum bee occurrence records, herbarium-derived flowering phenology models, site-specific floristic inventories, and published bee-plant interaction data, we estimated species-specific bee activity periods and daily floral …

The Influence Of Localized Water Quality On Eastern Oysters (Crassostrea Virginica) And Their Internal Microbiome Under Changing Environmental Conditions, Jessie Rivera Lafreniere

College of Graduate Studies: Theses & Dissertations

Oysters are found ubiquitously in estuaries along the Georgia coast, where marsh morphology and large daily tidal fluctuations create dynamic and stressful conditions to which oysters may be locally adapted. Based on water quality data from the Sapelo Island National Estuarine Research Reserve, it is evident that changing climatic conditions are rapidly causing shifts in water quality that may be adversely affecting oyster health, especially as ocean acidification alters the carbonate buffering capacity, increasing the amplitude of daily pH variations. Importantly, the rate of change of conditions are not uniform within estuaries, varying on spatial and temporal scales. The symbiotic …

Evaluating Benthic Macroinvertebrate Communities In Streamside Management Zones In Private, Working Forests, Haley Vaglienti

College of Graduate Studies: Theses & Dissertations

Forestry operations can alter riparian vegetation and increase sediment and nutrient inputs to streams, affecting water quality and aquatic biota. Forestry best management practices (BMPs) including streamside management zones (SMZs) are designed to mitigate those effects by reducing sediment delivery and moderating temperature, flow, and nutrient regimes. We assessed ecological integrity at 24 intermittent stream sites with SMZs in private, working forests across the Piedmont and Southeastern plains of Georgia. At each site, we conducted physical habitat evaluations and characterized benthic macroinvertebrate assemblages. Sites represented a gradient of habitat conditions, SMZ widths, and pine stand ages, allowing for comparisons of …

Cytonuclear Incompatibilities In Hybrid Systems: Oxidative Phosphorylation Capacity And Nuclear Marker Transmission Ratio Distortion In Hybrids Of An Introgressed Strain Of Parasitoid Wasp, Julie Kessler

College of Graduate Studies: Theses & Dissertations

Speciation is an evolutionary process resulting in the divergence of populations into reproductively isolated species, a key concept that supplies our planet with an abundance of biodiversity. Mechanisms for speciation center on obstacles to fertilization and include post-zygotic barriers, such as intrinsic deleterious interactions, that arise in hybrid systems where genetic variants are combined. Genes from separate parent lineages are often incompatible due to the co-evolution of paired genes within a singular species not matching their complement genes in another species, and the result is a reduction in fitness of the hybrid when these genes come together. The mitochondrial OXPHOS …

Intensified Push-Pull Technology Enhances Above-Ground Arthropod Assemblages And Ecological Balance, Evanson R. Omuse, Honest Machekano, Daniel M. Mutyambai, Bonoukpoe M. Sokame, Chrysantus M. Tanga, Johnson O. Nyasani, Sevgan Subramanian, Frank Chidawanyika

All Peer-Reviewed Publications

Agroecological intensification aims to increase farm productivity, reduce dependency on external inputs, and enhance biodiversity conservation. However, the contribution of recent sustainable agricultural practices to arthropod assemblages and their ecosystem services remains underexplored. Through a 2-year multilocation trial, we investigated the response of above-ground arthropod assemblages and their ecological functions in cowpea and maize grown under monocropping systems and diversified systems (pure and intensified push-pull technologies). Using three sampling methods (visual observations, pitfall traps, sticky traps), a total of 65, 307 arthropod specimens were collected. The most dominant arthropod taxa were Hemiptera (true bugs; 47%), followed by Thysanoptera (thrips; 17%), …

Homoplasy Of Maxillary Orthognathism In Derived Homo, Jared Jordan

Graduate Studies Theses and Dissertations 2026

The evolution of the orthognathic condition in the genus Homo represents a monumental transition toward the facial morphology of modern humans from that of earlier hominins, but the phylogenetic positioning of this transformation remains poorly understood. This study investigated temporal trends in maxillary and mandibular prognathism in the genus Homo, and whether maxillary and mandibular shortening in East Asian H. erectus and later East Asian Middle Pleistocene Homo (e.g., Homo longi) represent independent derivations of orthognathic morphology, thereby making orthognathism a homoplasy in the genus Homo. Using a sample of roughly 109 cranial and mandibular specimens spanning …

A Critical Perspective On The Society Of Environmental Toxicology And Chemistry's Adherence To Founding Principles— Opportunities For The Future, Barnett A. Rattner, Annegaaike Leopold, Carys L. Mitchelmore, Glenn W. Suter, Mark S. Johnson, Adriana C. Bejarano, Lawrence A. Kapustka, Niranjana Krishnan, Derek C. G. Muir, Beatrice O. Opeolu, Martha Georgina Orozco-Medina, April Reed, Bruce W. Vigon, Adam R. Wronski

Epidemiology, Biostatistics, & Environmental Health Faculty Publications

The Society of Environmental Toxicology and Chemistry (SETAC) is a global organization whose mission is the advancement of environmental science and management through collaboration, leadership, communication and education. On SETAC's 45th anniversary, the following question was raised: Are the 1979 founding principles of SETAC, multidisciplinary approaches to solving environmental problems, multisector engagement and scientific objectivity, still useful, adequate and effective in fulfilling its mission? In a special session held at the 45th Annual Meeting in Fort Worth, Texas, United States, a critical evaluation of the founding principles was initiated by reviewing SETAC's history and ongoing activities, and recommendations were made …

Moth Assemblages Of Fort Leonard Wood, Missouri, Kimberly Anne Steese

Masters Theses

"Moths (Lepidoptera) are ecologically important insects that function as herbivores, pollinators, prey resources, and indicators of ecosystem integrity. Despite their ecological significance, moth communities in the Missouri Ozarks remain poorly documented, particularly within military-managed landscapes. This thesis examined patterns of moth diversity, assemblage structure, and environmental drivers at Fort Leonard Wood (FLW), Missouri, while also assessing the distribution and genetic diversity of species within the genus Papaipema.

Field surveys were conducted from 2019 through 2021 across prairie, savanna, forest, and restoration habitats at FLW using UV bucket traps, sheet trapping, and targeted larval surveys. Across all sampling efforts, 29,116 individual …

A Note On The Novel Passive Sampling In Environmental Dna (Edna) Collection Technique To Detect Yellow Mud Turtle (Kinosternon Flavescens): Field And Laboratory Approaches In Turtle Edna, Sakib Tahmid Rishan, Richard J. Kline, Md. Saydur Rahman

School of Integrative Biological & Chemical Sciences Faculty Publications

Environmental DNA (eDNA) is a powerful and sensitive method for monitoring aquatic and terrestrial organisms, offering insights into their distribution. Usually, eDNA is collected using a filter membrane through water filtration. However, the passive eDNA method can simplify sampling and broaden its scope, offering new insights for ecological surveillance. This study examined the efficacy of six different membrane filters in detecting the yellow mud turtle (Kinosternon flavescens) through a novel passive eDNA method. After being immersed in water for 12 h, only the mixed cellulose ester (MCE) membrane filter consistently demonstrated specific polymerase chain reaction (PCR) amplification using …

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 …

Early Successional Response To Stream Daylighting In Redwood National And State Parks, Orick, California, Rylee Rawson

Cal Poly Humboldt theses and projects

In-channel stream restoration projects can act as both disturbance and recovery mechanisms, disrupting existing conditions to reestablish the hydrologic and ecological processes that sustain stream ecosystems. These interventions initiate successional trajectories in which channel form and biological communities reorganize over time. In Redwood National and State Parks (California, USA), the Redwoods Rising initiative restores buried headwater channels by recontouring legacy logging roads and daylighting streams buried by Humboldt crossings. Using the National Park Service Klamath Network wadable stream monitoring protocol, I evaluated nine restored reaches spanning one to five years post-restoration, alongside old-growth reference reaches and available pre-treatment data. I …

Postfire Habitat Use And Density Of Pacific Martens (Martes Caurina) In Lassen National Forest, California, Deirdre L. Replinger

Cal Poly Humboldt theses and projects

Increasing frequency, size, and severity of wildfires in western North America threatens forest-dependent wildlife species. The Pacific marten (Martes caurina) has historically been associated with mature, structurally complex forest throughout most of its range. Recently, martens have been detected in forests burned at high severity by the 2021 Dixie Fire—the largest recorded single fire in California state history. I used non-invasive remote camera traps and hair snares (n = 166 sites) to assess marten habitat use and density using spatial occupancy and spatial capture-recapture models. I detected martens across the burn severity gradient (unburned to high-severity) at …

Multiple Burn And Forest Characteristics Affect Gray Fox (Urocyon Cinereoargenteus) Occurrence Following A California Megafire, Amida Zohar Verhey

Cal Poly Humboldt theses and projects

In western North American forests, predator communities are faced with changing fire regimes and increased fire severity and size, particularly with megafires (>10,000 ha). As some wildlife communities may restructure following the loss of apex consumers, understanding post-fire space use of mid-trophic carnivores may inform species composition in these forests. I compared gray fox (Urocyon cinereoargenteus) occupancy in and around the 2021 Dixie Fire, the largest single-ignition fire in California state history, to examine which spatially variable burn and forest characteristics affected the space use of a widespread generalist mesopredator. Using 210 camera traps placed in 2023, …

Larval Crowding In Culex Pipiens Generates Cumulative Cascading Effects Under Changing Environmental Conditions, Sengul Talay, Zafer Sakaci, Michele C. Weigle, Bugrahan Regaip Kilinc, Jenah Parman, Holly Gaff, Deniz Sirin, Bulent Alten, Dennis Bente, Sirri Kar

Computer Science Faculty Publications

Density-dependent population regulation is a fundamental driver in the population dynamics of living systems, ensuring a balanced and sustainable maintenance in nature. It has been suggested that the adverse developmental and morphological effect of high larval density in container mosquitoes represents a significant limiting factor for population density, and the need to investigate this possible importance within the framework of field-based principles has been emphasized. This semi-field study, conducted under the natural thermal regime and using a natural population in Turkish Thrace, aimed to examine the effects of non-food-limiting larval density (crowding effect) in the mosquito species, Culex pipiens ( …

A Fine-Scale Genomic Study Of Cheat Mountain Salamanders (Plethodon Nettingi) On Managed Public Land, Amylynn Nicole Ephraim

Graduate Theses, Dissertations, and Problem Reports (ETD)

Habitat fragmentation has the potential to isolate localized populations, particularly those which are understood to have limited dispersal capabilities. This isolation can reduce genetic diversity through the effects of inbreeding depression, and small populations are more susceptible to the impacts of genetic drift. In this study, I aim to understand the level of genetic connectivity between known occupied patches of Cheat Mountain salamanders (Plethodon nettingi; CMS) on managed public land. CMS are a federally threatened, high-elevation, West Virginia endemic species associated with red spruce (Picea rubens) forests. I used double-digest restriction site associated DNA (ddRAD) sequencing …

Ecological Renovation Of Belmont Tennis Courts, Abbie E. Hamilton, Smith David, Darlene Panvini

SPARK Symposium Presentations

Although Belmont works hard to establish adequate green spaces on our campus, there is much work to be done if we want our students and the wildlife around us to maximize their ecosystem services. More specifically, Belmont can strive to implement nature-based solutions for its athletes, who are often competing in highly urbanized facilities. For this project, we have decided to redesign Belmont’s Tennis Courts, improving their design by increasing their green infrastructure. Our new design was created from a biophilic perspective and intends to serve all aspects of the triple bottom line. The new tennis courts will include ecologically …

A Sensory Ecology Of Fear: Moonlight-Mediated Predation Risk And Foraging Behavior In Neotropical Electric Fish, Chiu Lok Poon

Graduate Studies Theses and Dissertations 2026

Animals must forage to acquire energy for survival and reproduction, yet foraging exposes them to predators. This creates a trade-off between energy intake and safety, wherein the perception of predation risk alone can alter activity patterns. Within this trade-off, risk, energetic needs, and sensory adaptations vary, shifting the balance and favoring different foraging strategies. Using Neotropical electric fish as a study system, I investigated how foraging under predation risk is shaped across biological scales, including environmental dynamics, interspecific sensory differences, activity-timing mechanisms, and intraspecific variations. These nocturnal fish emit continuous electric signals to sense their environment, allowing non-invasive monitoring of …

Investigating Effects Of The Macroalga Caulerpa Prolifera On Restoration Of The Seagrass Halodule Wrightii In The Indian River Lagoon, Florida, Luciana M. Banquero

Graduate Studies Theses and Dissertations 2026

Seagrass restoration efforts have been motivated by global decreases in coverage associated with anthropogenic influences on the environment. In the Indian River Lagoon (IRL), FL, seagrass declined by 75% between 2011 and 2021. During this time, abundance of the macroalga Caulerpa prolifera increased substantially in the IRL. The macroalga is native to this estuary, however C. prolifera abundance has fluctuated widely in the past few decades. Being highly opportunistic, C. prolifera took advantage of areas formerly inhabited by seagrass. It is not known how dense, continuous beds of C. prolifera impact seagrass restoration projects or natural recovery of seagrass. Previous …

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 …

Managing Multi-Drug Resistance: An Evolutionary Game Theory And Optimal Control Approach, Shukhrat Nasrulloev

Theses and Dissertations

Multi-drug resistance is an evolutionary process in which treatment eliminates sensitive cells, allowing resistant clones to dominate. This thesis investigates this process using a framework integrating population dynamics, evolutionary game theory, and optimal control theory. We develop a two-population logistic growth model describing competition between drug-sensitive and drug-resistant cells under treatment, construct dose-dependent payoff matrices and replicator dynamics to characterize evolutionary competition, and derive a critical drug level D_crit = (r_S - rR)/(dS - d_R) at which resistant cells gain a fitness advantage. An optimal control problem is formulated via Pontryagin's Maximum Principle to identify schedules …

Interactive Effects Of Bti Larviciding And Predation On Culex Pipiens And Its Ephemeral Pond Communities, Jaclyn S. Everly

Theses and Dissertations

Populations of adult vector mosquitoes can be controlled by reducing larval mosquito abundances in aquatic habitats. This can be achieved via predation by introduced or naturally-occurring enemies (i.e., biocontrol or conservation control) or by applying pesticides to larval mosquito habitats (i.e., larviciding). The larvicide Bacillus thuringiensis israelensis (Bti) is commonly applied to ephemeral ponds to control populations of Culex pipiens mosquitoes that vector West Nile virus. However, there is concern that Bti may directly or indirectly harm non-target organisms such as dragonfly and damselfly naiads, which provide a natural source of mosquito biocontrol. Bti or predators may also induce positive …

Chemical Load: An Unseen Herbicide Filter In Restored Prairies?, Rylie Franklin

Electronic Theses and Dissertations

Community Assembly Theory is a framework used to describe the process by which species from a regional species pool disperse and encounter various abiotic and biotic conditions that act as filters, limiting which species will populate a specific local community. Prairie restoration success can be improved by understanding abiotic and biotic filters. As agricultural practices have adopted integrated weed management plans, that include the use of both chemical and non-chemical techniques, another filter needs to be considered during restoration: the chemical load of soils, i.e., herbicide residue from recent on-site applications and herbicide drift from adjacent areas. To examine the …

High Algal Biomass Is Decoupled From Metabolism In The Gallatin River, Cora Mae Steinbach

Graduate Student Theses, Dissertations, & Professional Papers

Assessing eutrophication in rivers is difficult compared to lakes and coastal waters, because most algal biomass occurs on the riverbed and flows interact and co-vary with production (Biggs and Close, 1989; Bernhardt et al., 2018). Riverine eutrophication is typically assessed using algal biomass and water column nutrients (U.S. Environmental Protection Agency, 2000), but biomass is highly variable and labor-intensive to measure, while nutrient concentrations often underestimate enrichment due to rapid biological uptake (Dodds and Smith, 2016). Reach-scale river metabolism can help evaluate long-term functional change in rivers recovering from nutrient enrichment (Arroita et al., 2019; Jankowski et al., 2021; Diamond …

Aquatic Habitat Use By Western Toads And American Bullfrogs In California’S Central Valley: Effects Of Local Habitat Characteristics And Landscape Composition, Kaitlyn Breana Hernandez

Cal Poly Humboldt theses and projects

Drastic losses of historic wetland habitat in the California Central Valley have caused widespread population declines and extirpations of aquatic breeding amphibians. Efforts to restore wetland habitat have included private land, which represents 70% of land tenure in the Central Valley. Management of these restored wetlands is focused on waterfowl with the assumption that they will provide habitat for native herpetofauna. This study used combined surveys to test the assumption that restored wetlands on private land provide habitat for native amphibians with the western toad (Anaxyrus boreas) as a case study. The objectives were to use environmental DNA …

Coho Salmon (Oncorhynchus Kisutch) Response To Habitat Restoration Through Space And Time: Monitoring Growth, Survival, And Movement In A Restored Habitat Network, Carter Perez Adamson

Cal Poly Humboldt theses and projects

Despite the decline of coho salmon (Oncorhynchus kisutch), Prairie Creek, a tributary of Redwood Creek in northern California, remains a coho salmon stronghold. The restoration of juvenile coho rearing habitat was identified as a recovery objective in this watershed by the National Marine Fisheries Service. Among the restoration projects addressing this objective are an ongoing project on Prairie Creek and its tributary Skunk Cabbage Creek, and a prior effort on Strawberry Creek (a tributary of Redwood Creek’s estuary). Standard monitoring methods for assessing project success have limitations and may be improved by measuring salmon use of restored habitats …

Ectomycorrhizal Fungi Associated With Pinus Species Of California's Northwestern Coast, Monika Audrey Richardson

Cal Poly Humboldt theses and projects

Ectomycorrhizal (ECM) fungi are vital for increasing host plant uptake of nutrients and stress tolerance within ECM forest ecosystems. The species assemblage of ECM fungi can vary locally in response to numerous biotic and abiotic environmental factors. In California’s northwestern coast the occurrence of three Pinus species, along with a disjunction between populations of Pinus muricata in Mendocino and Humboldt Counties, offer a unique opportunity to investigate the spatial and host effects on pine-associated ECM fungi. Ectomycorrhizal fungal community structure was quantified from host tree roots and sequenced sporocarps occurring at the same sites to create a project specific ITS …

Integrating Multi-Method Monitoring To Characterize Seasonal Habitat Use Of Green Sturgeon (Acipenser Medirostris) In Humboldt County, California, Olivia S. Boeberitz

Cal Poly Humboldt theses and projects

Green sturgeon (Acipenser medirostris) are a long-lived, anadromous, iteroparous species that spawns in large West Coast North American rivers but ranges widely in the coastal ocean. For coastal California Native American Tribes, green sturgeon are a vital part of their cultural heritage and traditions, and central to their food security. Two genetically distinct population segments (DPSs) of green sturgeon are recognized in the United States, Canada, and Mexico; the southern DPS is listed as “threatened” under the Endangered Species Act and the northern DPS is considered of “conservation concern.” Although green sturgeon are known to use large estuaries …

Evidence Of Personality And Movement Syndromes In A Mobile Predator: How Individual Hunting Strategy Shapes Ecosystem Service Potential By Barn Owls (Tyto Furcata) In An Agroecosystem, Lauren M. Jackson

Cal Poly Humboldt theses and projects

Animal-mediated ecosystem services are delivered through the behavior of individuals, yet most studies evaluate service-providing species at the population level. We tested whether individual variation in plumage, behavior, and movement predicted hunting behavior and vineyard habitat use by adult male American barn owls (Tyto furcata) nesting in winegrape vineyards in Lodi, California, USA. We fitted GPS-accelerometer tags to 42 breeding males, quantified breast-plumage traits, measured neophobia using repeated novel object tests, and derived nightly movement metrics from GPS tracks and hidden Markov model-classified hunting locations. Several behavioral traits were repeatable, but movement traits showed the clearest repeatable individual …

Symmetry In Affiliative Interactions Of North American River Otters (Lontra Canadensis) In A Northern California Estuary, Charlotte E. Norman

Cal Poly Humboldt theses and projects

Patterns of participation in affiliative behaviors may reflect underlying social dynamics. Two affiliative behaviors, allogrooming and social play, were assessed for their symmetry, or relative participation of participants, in a wild group of North American river otters. Behavioral observations were conducted over five months at the Little River estuary in northern California using video recordings and all-occurrence sampling. Observations included all-adult groups, a family group consisting of a breeding female and two pups, and an extended family group with one or two helpers, indicative of cooperative breeding. Individuals engaged in allogrooming and social play were classified by their group membership, …

Green Connectivity In Metropolitan Jabodetabek: Climate Change And The Challenge Of Urban Forest, Safira Maharani Putri, Hendricus Andy Simarmata

CSID Journal of Infrastructure Development

Urban areas in Indonesia, particularly the Greater Jakarta metropolitan region (Jabodetabek), are increasingly experiencing the adverse effects of climate change, such as the Urban Heat Island (UHI) phenomenon. Rapid urbanization has contributed significantly to rising greenhouse gas emissions and deteriorating environmental quality. Urban forests are one of the key solutions to mitigate these impacts; however, their spatial distribution in Jabodetabek remains suboptimal and poorly connected. This study uses NDVI as a proxy for urban forest density, where “urban forest” refers to vegetated areas within cities as defined by Presidential Regulation No. 60/2020. The research addresses the following question: How has …