Population Biology Commons^™

Diversification Of Avifauna In The Darién Highland Region: Ecological Niche Modeling, Phylogeography And Morphology To Explore Speciation In The Montane Species Myadestes Coloratus, Chlorospingus Tacarcunae And Margarornis Bellulus., Jorge L. Garzon Vasquez Mrs

Theses and Dissertations

Montane regions in the Neotropics are hotspots of endemism and biodiversity, yet their species are especially vulnerable to the impacts of climate change and geographic isolation. This thesis investigates the evolutionary and ecological dynamics of three bird species endemic to the Darién Highlands of eastern Panama: Myadestes coloratus, Chlorospingus tacarcunae, and Margarornis bellulus. Through an integrative approach combining ecological niche modeling, morphometric analysis, and genomic data from ultraconserved elements (UCEs) and mitochondrial DNA, the study explores the historical biogeography, current distribution patterns, population structure, and phenotypic differentiation of these montane taxa. Ecological niche models revealed that suitable habitat …

Predicting Capture And Survival Probabilities Of The Arizona Tiger Salamander: A Comparison Of Capture-Recapture Models, Brittney Nelson

Murray State Theses and Dissertations

Capture-recapture models are essential tools for estimating population dynamics in ecological studies. A fundamental component of these models is the capture history matrix, which records individual detection over time and serves as the basis for estimating survival and capture probabilities. This presentation explores three statistical approaches to these estimations: the Cormack-Jolly-Seber (CJS) model, the Hidden Markov Model (HMM) for CJS, and the Bayesian CJS model. The CJS model provides a likelihood-based framework for estimation, and the HMM CJS incorporates latent states into the model to account for uncertainty in detection. The Bayesian CJS extends this same analysis by integrating prior …

Jaguar (Panthera Onca) Population Status And Conservation Needs In Panama Revealed Using Spatial Density And Occupancy Models., Rebeca E. Becdach

Cal Poly Humboldt theses and projects

Jaguars (Panthera onca) are key predators and the largest felid in the Americas. The species is listed as near threatened globally due to habitat loss, fragmentation, and human persecution. Their population decline can negatively affect the structure and functioning of the ecosystems they inhabit. Conservation efforts for jaguars and their habitat require understanding jaguar populations and how they are impacted by human presence across their range. This information is lacking in Panama, a critical portion of the Jaguar range. Panama forms a narrow land bridge connecting Central and South America, integral to wildlife movement, including jaguars, across both …

Bat Species Diversity In The Klamath Basin Prior To Dam Removals, Ryan Page Matilton

Cal Poly Humboldt theses and projects

River ecosystems make up a small percentage of the earth’s surface, but they support high levels of biodiversity and attract high levels of human use. Dams, for example, disrupt a river’s natural course and flow, alter water temperatures in the stream, redirect river channels, transform floodplains, and fragment river continuity, which affects ecological balance and food webs. The Klamath River in northern California, which has been dammed for the last century, experienced dramatic disruptions including a large fish die-off in 2002. With the negative impacts of the Klamath dams apparent, multiple entities negotiated to remove the dams and restore the …

Habitat Use And Selection Of Silver Carp In The Lower Wabash River System, Coy B. Blair

Masters Theses

The spatial ecology of non-native species in invaded systems remains relatively poorly understood despite the importance of suitable habitat in the success of invasion. Silver Carp Hypophthalmichthys molitrix are a highly invasive non-native species with established populations throughout the Midwestern United States. Much research has focused on habitat use of bigheaded carp in large river systems, though invasion risk remains high in smaller systems, such as tributaries of the Great Lakes and the Ohio River. The Wabash River, a unique system in the Midwest, remains largely un-impounded and is comparable to many of the smaller riverine systems at risk of …

Assessing The Behavioral And Health Effects Of Turtle Racing On Eastern Box Turtles (Terrapene Carolina Carolina), Michelle Weaver

Murray State Theses and Dissertations

To make informed management decisions regarding box turtles (Terrapene spp.) and other turtle species, one must understand what influences them at multiple levels of biological organization. Common influences include the pet trade, urbanization, habitat degradation, and disease. One factor that has not been studied but could influence turtles at multiple levels of biological organization is turtle racing. It is common practice to use wild caught turtles at these events because there is a lack of regulation and enforcement. My study focused on evaluating the effects of turtle racing on eastern box turtles (Terrapene carolina carolina; hereafter EBTs) …

History, Annotated Gazetteer, And Bibliography Of Ornithology In Kalimantan, Indonesian Borneo, Frederick H. Sheldon, Mohammad Irham, Daisy G. S. Kho, Erik Meijaard, Subir B. Shakya, Dewi M. Prawiradilaga, Sebastianus (Bas) Van Balen

Occasional Papers of the Museum of Natural Science, Louisiana State University

Kalimantan comprises nearly three quarters of the island of Borneo and is the place where scientific study of Bornean birds began. We describe the history of bird research in Kalimantan from its beginning, highlighting the ornithologists who explored the region and how their interests and methods changed over time, from a concentration on specimen collection, to examinations of community ecology, to conservation in the face of habitat change and species depletion, to the latest investigations using satellite, genetic, and digital technology. We also highlight some future directions for research, especially the need for more work on basic ecology and biogeography. …

Epigenetic Potential Remains Stable Over 100 Years After Introduction, Danielle Dawkins

College of Graduate Studies: Theses & Dissertations

Introduced species provide important insights into organismal behavioral responses. Epigenetic mechanisms are one of the various ways in which behaviors can be modified, particularly through DNA methylation. Through such mechanisms, phenotypic changes can occur in response to environmental changes, allowing an organism to be more plastic. Epigenetic potential (EP) represents the capacity for an organism to be epigenetically modified, and can be measured by counting CpG motifs; cytosine adjacent to guanine within a DNA sequence. Phenotypic plasticity as it relates to EP has been studied extensively in the house sparrow (Passer domesticus), a globally introduced songbird. It is …

Crisis In The Current: A Proposed Study On The Impact Of Columbia River Basin Water Quality On Juvenile Chinook Salmon Survival, Olivia Buist-Thuillier

Pitzer Senior Theses

Salmon occupy a vital role in the ecosystem, economy, and indigenous culture of the Pacific Northwest of the United States, specifically within the Columbia River Basin. Of the five species of Pacific Salmon that live in the basin, Chinook salmon (Oncorhynchus tshawytscha) are the most widely commercially fished and are the largest. In recent years, Chinook Salmon populations have heavily declined from human influence. Rising temperatures from anthropogenic climate change, habitat destruction (dams, human presence), runoff from agricultural practices, and overfishing have all contributed to this decline. Because of their role as a keystone species and their cultural significance, there …

‘Who’S Your Daddy?’: Ddradseq Parentage In Broodstock-Offspring Pairs Of Diadema Antillarum In A Population Restoration Initiative, Bianca R. Rosendahl

Undergraduate Scholarship and Creative Works

In the early 1980s Diadema antillarum, or the long-spined urchin, was hit by a catastrophic mass mortality event across the western Atlantic and Gulf of Mexico, inclusive of the Florida Keys. The cause of this die-off event was likely triggered by a pathogen or environmental stressor that decimated native populations by up to 98%. The species has not yet fully recovered and is struggling with recruitment success which is why it may benefit from an ex-situ recovery program. In this study, I used single nucleotide polymorphisms (SNPs) to identify genetic variation and analyze parentage in a captive population of …

In The Footsteps Of Moose: Using Non-Invasive Techniques To Identify Cause-Specific Calf Mortalities And Evaluate Moose (Alces Alces) Movements Pertaining To Mineral Lick Locations On Ancestral Lands Of The Grand Portage Ojibwe, Anna B. Weesies

Electronic Theses and Dissertations

Following a sharp moose (Alces alces; mooz, Anishinaabemowin, Ojibwe language) population decline in northeastern Minnesota during the early 2000s, the Grand Portage Band of Lake Superior Chippewa initiated a long-term moose collaring effort to assess survival and mortality causes. Moose are a culturally important species to the Band, with annual subsistence hunts held on the Reservation and adjacent 1854 Ceded Territory. Continued research guides culturally appropriate management decisions aimed at bolstering calf and adult survival, helping to preserve this moose in Minnesota today and for subsequent generations. Chapter 1 identifies cause-specific calf mortality rates in this multi-predator system using minimally …

The Influence Of Bottom-Up And Top-Down Effects On The Density And Distribution Of Common Leopards In The Eastern Himalayas, Karma Choki

Electronic Theses and Dissertations

Leopards (Panthera pardus fusca) are widely distributed across Asia, yet their conservation is overshadowed by the conservation status of other flagship predators like tigers (Panthera tigris), in the Eastern Himalayas. Despite their ability to coexist with other large carnivores, leopard populations are shaped by intricate ecological interactions and increasing human pressures. This thesis investigates the abundance and density, habitat use, and drivers of persistence of leopards across Bhutan to inform multi-species carnivore conservation planning. My first chapter provides an overview of the ecological roles of large carnivores and how they persist on the landscape. I review the mechanisms that facilitate …

Tricolored Bat (Perimyotis Subflavus) Population Genetic Structure In The Southeastern United States, Laura Henderson

Master's Theses

Tricolored bats (Perimyotis subflavus) have experienced substantial population losses from white-nose syndrome (WNS), a disease caused by the pathogenic fungus Pseudogymnoascus destructans (Pd) which infects hibernating bats. Determining population genetic structure helps assess genetic diversity and the impacts of wildlife threats to populations. Pre-WNS data shows weak-to-negligible structure and panmictic P. subflavus populations at core portions of their range. However, current genetic data from their southeastern U.S. range is lacking. I sought to determine whether recent genetic data help resolve genetic structure among southeastern populations and assess genetic differences at two stages of impact: post-WNS and …

Just Keep Swimming: Outmigration Survival Of Upper Klamath Basin Juvenile Chinook Salmon, James M. Whelan

Cal Poly Humboldt theses and projects

The removal of four impassable hydroelectric dams on the Klamath River provides salmonids with the opportunity to recolonize their historic range in the upper Klamath River watershed. However, successful reestablishment of salmon populations requires juvenile salmon born in Oregon's upper tributaries to safely migrate downstream through the river's upper reaches. This stretch of the Klamath River, immediately downstream of Upper Klamath Lake, presents multiple migration challenges, including two flow-control dams not scheduled for removal (Link River Dam and Keno Dam), significant water diversions, and water quality issues. To evaluate these challenges, I conducted experimental releases of radio-tagged juvenile Chinook salmon …

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 …

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 …

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 …

Ina Scuba: Mobilization Of French West Indies Scuba Diving Clubs To Rapidly Improve Knowledge On Threatened Marine Species. Case Of The White-Spotted Eagle Ray (Aetobatus Narinari)., Océane Beaufort, Rocio Prieto González

Gulf and Caribbean Research

The White—Spotted Eagle Ray (Aetobatus narinari), listed as Endangered on the IUCN Red List since 2021, is experiencing alarming population declines, underscoring the urgent need for targeted conservation efforts. This species, which plays a vital ecological role in marine food webs, has biological and ecological characteristics that make it particularly vulnerable to habitat degradation and anthropogenic pressures, particularly fishing, tourism, and maritime traffic. In the French West Indies (FWI), the paucity of data on the White—Spotted Eagle Ray remains a major obstacle to the development of effective, island—specific conservation strategies. To address this gap, the INA Scuba participatory …

Oyster Horizons: Spatial Prioritization For Oyster Restoration At Alabama Living Shorelines, Trinity Henry-Jack, Aaron Bland, Christa Russell, Ronald Baker

Gulf and Caribbean Research

No abstract provided.

Assessing The Effects Of Wildfire Season Pm2.5 Exposure And Environmental Variables On Breeding Season Avian Body Condition, Cira Seyer-Ochi

Scripps Senior Theses

The increasing frequency and intensity of wildfires pose growing threats to wildlife, yet the indirect effects of wildfire smoke on avian populations remain largely unstudied. This exploratory study provides an initial assessment of how particulate matter 2.5 (PM2.5) associated with smoke pollution from the 2017 California wildfire season, in conjunction with precipitation and habitat type, influences the body condition of four resident bird species during the 2018 breeding season. Using bird banding data from 29 Monitoring Avian Productivity and Survivorship (MAPS) stations, I assessed the potential interactions between PM2.5 concentrations, precipitation, and habitat type with body condition for Song Sparrows …

Cost-Effective Strategies For Feral Swine Control: Exploring Trapping Equipment Cooperatives, Phil Kenkel, Riza Radmehr, Rodney Holcomb, Mckenzie Boyce

Human–Wildlife Interactions

Feral swine (Sus scrofa) in the United States have become a growing concern, with a population of ≥6 million and causing annual damages of ≥$1.5 billion USD. Because of their high reproductive capacity, effective control methods are crucial to reducing or slowing their population growth. While remotely monitored and triggered traps have proven to be an effective control strategy, the cost of sophisticated trapping equipment, which can cost ≥$7,000 USD, is often cost prohibitive for many landowners. Despite the pressing need to address the challenge of making effective feral swine control methods more affordable, there are few studies …

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 …

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 …

Acer Rubrum: Descending Towards Forest Dominance, Elyssa L. Pearson, Christopher M. Gough

Undergraduate Research Posters

Acer rubrum, more commonly known as the red maple, is a hardwood, late successional species of tree commonly planted for its deciduous nature and vibrant coloring of its leaves in the beginning of autumn (Abrams, 1998). The species is very tolerant of varying light and soil moisture levels and often dominates sub and mid-canopy levels of hardwood forests (Missouri Botanical Gardens). It was hypothesized that as the I moved from an upland location to a lowland location near a wetland that the A. rubrum trees would be more productive and have a greater above ground biomass. This was not …

Better Together: Leveraging Existing Research To Evaluate Population Trends, Habitat Selection, And Species Interactions Of Mesocarnivores, Jordan Lee Heiman

Graduate Student Theses, Dissertations, & Professional Papers

Whether from human impacts, climate change, or extreme fires, landscapes around the world are rapidly changing (Foley et al. 2005, Grimm et al. 2008, Bowman et al. 2020). As these landscapes change, it is clear that many ecosystems and species are being negatively affected (Laliberte and Ripple 2004, Butchart et al. 2010, Freeman et al. 2018, Li et al. 2022). With an expanding number of species facing extinction risks, it is critical for agencies to know when and where to focus their limited resources and conservation efforts (Martin et al. 2012, Auerbach et al. 2014, Bal et al. 2018). To …

Binoculars To Bytes: Development And Field Validation Of An Ai-Driven System For Avian Monitoring, Christian J. Dupree

Graduate Student Theses, Dissertations, & Professional Papers

Autonomous camera-trap arrays coupled with artificial-intelligence (AI) vision can lift bird monitoring beyond the spatial, temporal, and labor limits of traditional field surveys. We present Binoculars to Bytes (B2B), an open-source pipeline that turns 180–360° time-lapse imagery into analysis-ready avian data. At Freezout Lake Wildlife Management Area (Montana, USA) the system ran four-hour morning deployments during spring and fall migrations (2023–2024). A YOLO-NAS detector, incrementally refined with a “Specialized Localized Iterative Model” workflow, quadrupled local accuracy and, after confidence-based species-binning, cut false-positive rates in half. Daily AI species lists were benchmarked against contemporaneous eBird citizen-science checklists and recovered ≥ …

Exploring Coastal Plain Fish Ecology Across A Range Of Early-Life-History Traits And River Types, Bridgette Nicolosi

College of Graduate Studies: Theses & Dissertations

The ecological complexity of southeastern Coastal Plain rivers is reflected in the diversity of fish communities they support, yet the processes structuring early life dynamics remain poorly understood. This thesis explores the influence of environmental gradients on larval fish assemblage composition and American Shad (Alosa sapidissima) spawning phenology across two Georgia Coastal Plain river systems.

In the unregulated Ogeechee River, I investigated spatial and temporal variation in larval fish communities by comparing mainstem and tributary habitats to understand the role of tributaries in watershed-wide larval production. Larvae were collected biweekly from May to September 2024 at eight paired mainstem-tributary sites …

Divergent Floral And Vegetative Trait Responses To Abiotic Factors Drive Phenotypic Diversity In Platanthera Dilatata (Orchidaceae) Across Alaska, Marlin L. Bowles, Lisa E. Wallace

Biological Sciences Faculty Publications

Multiple traits make up an integrated phenotype, but traits may be shaped by differing drivers. It is often assumed that selection by biotic agents drives floral variation, but abiotic factors are also known to influence floral traits. Understanding trait covariations and their association with diverse environmental factors is a central question in evolution and ecology. Here, we studied covariation in floral and vegetative traits in relation to climate and topo-edaphic variation in the orchid Platanthera dilatata. In Platanthera, nectar spur length is associated with pollinator tongue length, but much variation exists in other traits too, likely to be …