Population Biology Commons^™

Estimating The Distribution Of Oryzomys Palustris, A Potential Key Host In Expanding Rickettsial Tick-Borne Disease Risk, Catherine A. Lippi, Samuel Canfield, Christina Espada, Holly D. Gaff, Sadie J. Ryan

Biological Sciences Faculty Publications

Increasingly, geographic approaches to assessing the risk of tick-borne diseases are being used to inform public health decision-making and surveillance efforts. The distributions of key tick species of medical importance are often modeled as a function of environmental factors, using niche modeling approaches to capture habitat suitability. However, this is often disconnected from the potential distribution of key host species, which may play an important role in the actual transmission cycle and risk potential in expanding tick-borne disease risk. Using species distribution modeling, we explore the potential geographic range of Oryzomys palustris, the marsh rice rat, which has been …

Utilizing Markov Chains To Estimate Allele Progression Through Generations, Ronit Gandhi

Honors Program: Senior Projects (Public)

All populations display patterns in allele frequencies over time. Some alleles cease to exist, while some grow to become the norm. These frequencies can shift or stay constant based on the conditions the population lives in. If in Hardy-Weinberg equilibrium, the allele frequencies stay constant. Most populations, however, have bias from environmental factors, sexual preferences, other organisms, etc. We propose a stochastic Markov chain model to study allele progression across generations. In such a model, the allele frequencies in the next generation depend only on the frequencies in the current one.

We use this model to track a recessive allele …

Pond-Breeding Amphibian Responses To Wetland Creation And Reforestation On A Legacy Surface Mine In The Monongahela National Forest, Lauren Breanna Sherman

Theses and Dissertations--Forestry and Natural Resources

Surface mine reclamation has been an evolving practice since the Surface Mining Control and Reclamation Act was passed in 1977, holding mining companies accountable for returning ecological function to areas directly impacted by mining activities. One recent method of reclamation, the Forestry Reclamation Approach (FRA), aims to enhance reforestation and ecosystem function through the creation of wetlands, as opposed to traditional methods that often revert land to grasslands. However, wildlife response to FRA has rarely been investigated. The goal of this project was to analyze the effects of the four treatment types, FRA in two chronosequences, natural regeneration, and unmined …

Chemical Immobilization Of Helicopter-Captured Elk (Cervus Canadensis) And Survival Of Elk Calves In Southeastern Kentucky, Kathleen E. Williams

Theses and Dissertations--Forestry and Natural Resources

Safe and effective chemical immobilization is critical to minimize stress and risk of injury when capturing free-ranging, wild ungulates. Many traditionally favored high potency opioids have been phased out or become unavailable because of increased regulations, leading to the development of two pre-mixed combination drugs, butorphanol-azaperone-medetomidine (BAM) and nalbuphine-medetomidine-azaperone (NalMed-A). Both drugs have been used to chemically immobilize ungulates, but their efficacy has not been documented in elk captured and transported via helicopter. During 2020 – 2022, we chemically immobilized helicopter-captured female elk (Cervus canadensis) with a single IM-injection of BAM (n = 41) or NalMed-A (n = …

Prevalence Of Hesperevax Sparsiflora Var. Brevifolia (Short-Leaved Evax) At Ocean Ranch, Humboldt County, California: Exploring The Effects Of Disturbance, Shelby Diquirco, Matthew Estrada, Alana T. Fraley, Alexander D. Smith

Environmental Science & Management Senior Capstones

The prevalence of special-status plants within a landscape can be an indicator of the ecological health of that site, and therefore inform restoration efforts and post-restoration monitoring. Hesperevax sparsiflora var. brevifolia (short-leaved evax) is a special status species found within the Ocean Ranch unit of Humboldt, California. A primary threat to native plant communities are invasive plant species. Coastal dune ecosystems are largely dominated by invasive species, including Ammophila arenaria (European beachgrass). To work towards the eradication of A. arenaria, the California Department of Fish and Wildlife utilized treatment combinations of herbicide and prescribed fire at Ocean Ranch in …

Unraveling A Paradox Of Habitat Relationships: Scale-Dependent Drivers Of Temporal Occupancy-Abundance Relationships In A Cooperatively Breeding Bird, Natasha D.G. Hagemeyer, Mario B. Pesendorfer, Walter D. Koenig, Eric L. Walters

Biological Sciences Faculty Publications

Context Spatial occupancy and local abundance of species often positively covary, but the mechanisms driving this widespread relationship are poorly understood. Resource dynamics and habitat changes have been suggested as potential drivers, but long-term studies relating them to abundance and occupancy are rare. In this 34-year study of acorn woodpeckers (Melanerpes formicivorus), a cooperatively breeding species, we observed a paradoxical response to changes in habitat composition: despite a reduction in the availability of high-quality breeding habitat, the population increased considerably.

Objectives We investigated the role of annual variation in food availability and long-term changes in habitat composition as predictors …

Western Gulls’ (Larus Occidentalis) Reproductive And Behavioral Responses To Human Disturbance, Lilamarie 'Asta Bowen

Cal Poly Humboldt theses and projects

Human disturbances can negatively affect wildlife by causing stress, altering behavior, or even impacting populations through changes in survival or productivity. Colonial-nesting seabirds are of particular concern due to population declines and their gregarious and conspicuous nature, which may attract human visitors. However, the effects of nearby human activities, though frequently negative, could be neutral or even positive through phenomena like habituation to human activities or subsidization by human-supplied food sources. In this observational study, I evaluated relative support for three hypotheses which may explain how Western Gulls are impacted by human activity: disturbance, habituation, and subsidization. I investigated this …

Straight From The Coyote’S Mouth: Genetic Identification Of Prey Through Oral Swabs Of Predators, Julie K. Young, Amanda M. Mast, James A. Walton, Torrey Rodgers, Antionette J. Piaggio, Daniel R. Taylor, Karen E. Mock

United States Department of Agriculture Wildlife Services: Staff Publications

Human-carnivore conflicts often involve the depredation of domestic livestock. These depredation events are rarely observed, yet mitigation typically involves identifying the species or individual involved for removal or relocation. We tested a molecular method to identify individuals involved in depredation events using mouth swabs to determine if prey DNA could be detected, and for how long. We fed mule deer Odocoileus hemionus meat to captive coyotes Canis latrans and swabbed their mouths at five predetermined intervals between 2–72 h after consumption of the deer meat. We assessed two different molecular forensic methods to analyze the saliva swabs: qPCR for species …

Movements And Resource Selection Of Wild Pigs Associated With Growth Stages Of Corn, Bethany A. Friesenhahn, Randall W. Deyoung, Michael J. Cherry, Humberto L. Perotto-Baldivieso, Kurt C. Vercauteren, Nathan P. Snow

United States Department of Agriculture Wildlife Services: Staff Publications

Wild pigs (Sus scrofa) are one of the most successful invasive species globally and are often implicated in agricultural damage. This damage is expected to increase as ranges of wild pigs expand, impacting the human food supply and increasing costs of food production. Our objective was to evaluate movement behaviors of wild pigs relative to resource availability and landscape features in an agriculture-dominated landscape, with a goal of informing management practices for reducing damage to corn. We monitored hourly movements of adult wild pigs relative to corn crops using GPS collars during the 2019 and 2020 growing seasons (Feb–Sept) in …

Burmese Pythons In Florida: A Synthesis Of Biology, Impacts, And Management Tools, Jacquelyn C. Guzy, Bryan G. Falk, Brian J. Smith, John David Willson, Robert N. Reed, Nicholas G. Aumen, Michael L. Avery, Ian A. Bartoszek, Earl Campbell, Michael S. Cherkiss, Natalie M. Claunch, Andrea F. Currylow, Tylan Dean, Jeremy Dixon, Richard Engeman, Sarah Funck, Rebekah Gibble, Kodiak C. Hengstebeck, John S. Humphrey, Margaret E. Hunter, Jillian M. Josimovich, Jennifer Ketterlin, Michael Kirkland, Frank J. Mazzotti, Robert Mccleery, Melissa A. Miller, Matthew Mccollister, M. Rockwell Parker, Shannon E. Pittman, Michael Rochford, Christina Romagosa, Art Roybal, Ray W. Snow, Mckayla M. Spencer, J. Hardin Waddle, Any A. Yackel Adams, Kristen M. Hart

United States Department of Agriculture Wildlife Services: Staff Publications

Burmese pythons (Python molurus bivittatus) are native to southeastern Asia, however, there is an established invasive population inhabiting much of southern Florida throughout the Greater Everglades Ecosystem. Pythons have severely impacted native species and ecosystems in Florida and represent one of the most intractable invasive-species management issues across the globe. The difficulty stems from a unique combination of inaccessible habitat and the cryptic and resilient nature of pythons that thrive in the subtropical environment of southern Florida, rendering them extremely challenging to detect. Here we provide a comprehensive review and synthesis of the science relevant to managing invasive …

Effects Of Corn Supplementation On Serum And Muscle Microrna Profiles In Horses, Clarissa Carver, Jason E. Bruemmer, Stephen Coleman, Gabriele Landolt, Tanja Hess

United States Department of Agriculture Wildlife Services: Staff Publications

Laminitis associated with equine metabolic syndrome causes significant economic losses in the equine industry. Diets high in non-structural carbohydrates (NSC) have been linked to insulin resistance and laminitis in horses. Nutrigenomic studies analyzing the interaction of diets high in NSCs and gene expression regulating endogenous microRNAs (miRNA) are rare. This study's objectives were to determine whether miRNAs from dietary corn can be detected in equine serum and muscle and its impacts on endogenous miRNA. Twelve mares were blocked by age, body condition score, and weight and assigned to a control (mixed legume grass hay diet) and a mixed legume hay …

Using Drones To Detect And Quantify Wild Pig Damage And Yield Loss In Corn Fields Throughout Plant Growth Stages, Bethany A. Friesenhahn, Lori D. Massey, Randy W. Deyoung, Michael J. Cherry, Justin W. Fischer, Nathan P. Snow, Kurt C. Vercauteren, Humberto L. Perotto‐Baldivieso

United States Department of Agriculture Wildlife Services: Staff Publications

Presently, there are an estimated 6.9 million wild pigs (Sus scrofa) in the U.S., which cause over US$1 billion in damage to agriculture, environmental impacts, and control costs. However, estimates of damage have varied widely, creating a need for standardized monitoring and a method to accurately estimate the economic costs of direct wild pig damage to agriculture. The goal of our study was to integrate remotely sensed imagery from drones and crop harvest data to quantify wild pig damage in corn fields. We used drones with natural color (red, green, blue) cameras to monitor corn fields at different …

Intracellular Diversity Of Wnv Within Circulating Avian Peripheral Blood Mononuclear Cells Reveals Host-Dependent Patterns Of Polyinfection, Dalit Talmi-Frank, Alex D. Byas, Reyes Murrieta, James Weger-Lucarelli, Claudia Rückert, Emily N. Gallichotte, Janna A. Yoshimoto, Chris Allen, Angela M. Bosco-Lauth, Barbara Graham, Todd A. Felix, Aaron C. Brault, Gregory D. Ebel

United States Department of Agriculture Wildlife Services: Staff Publications

Arthropod-borne virus (arbovirus) populations exist as mutant swarms that are maintained between arthropods and vertebrates. West Nile virus (WNV) population dynamics are host-dependent. In American crows, purifying selection is weak and population diversity is high compared to American robins, which have 100- to 1000-fold lower viremia. WNV passed in robins leads to fitness gains, whereas that passed in crows does not. Therefore, we tested the hypothesis that high crow viremia allows for higher genetic diversity within individual avian peripheral blood mononuclear cells (PBMCs), reasoning that this could have produced the previously observed hostspecific differences in genetic diversity and fitness. Specifically, …

Investigating Nocturnal Uas Treatments In An Applied Context To Prevent Gulls From Nesting On Rooftops, Morgan Pfeiffer, Craig K. Pullins, Scott F. Beckerman, Joshua L. Hoblet, Brad Blackwell

United States Department of Agriculture Wildlife Services: Staff Publications

Ring‐billed (Larus delawarensis) and herring (L. argentatus) gulls are numerous and widespread in North America. These gulls rank among the top 9 species for risk of bird‐aircraft collisions (hereafter strikes). The ubiquitous presence of gulls in urban coastal environments, including rooftop nesting behavior, are factors impacting strike risk. Our purpose was to assess gull response to a small uncrewed aircraft system (UAS) in hazing flights at night during the nest‐building phase. We hypothesized that nocturnal UAS operation, like nocturnal predator disturbance, might reduce gull numbers and, thus, strike risk to aircraft. In spring 2021, we conducted …

Urbanization Influences Spatiotemporal Patterns Of Roost Site Selection By Black Vultures And Turkey Vultures, Jacob E. Hill, Kenneth F. Kellner, Amanda E. Holland, Bryan M. Kluever, Morgan B. Pfeiffer, Travis L. Devault, Jerrold L. Belant

United States Department of Agriculture Wildlife Services: Staff Publications

Roost locations can be an important contributor to vulture conflicts with humans, but factors influencing roost-site selection at a landscape level remain largely unexplored. Further, there has been little research comparing how these factors vary between nocturnal and diurnal roosting sites. We used remote cameras to document daily variation in vulture use of 21 roosts (20 communication/water towers and 1 natural roost) near Beaufort, South Carolina, USA from October 2019–August 2020. Numbers of vultures on roosts increased with decreasing urban cover and with greater distance to water, but were not influenced by habitat fragmentation or elevation. Roosts surrounded by greater …

Table Of Contents

Human–Wildlife Interactions

This is the table of contents.

The Lord Howe Island Rodent Eradication: Social And Technical Lessons For Inhabited Islands, Grant A. Harper, Simon Pahor, Kelly Harrington, Darcelle Matassoni, Darryl Birch

Human–Wildlife Interactions

The 2019 rodent eradication on 1,455-ha Lord Howe Island, Australia, was the second and largest attempted on a permanently inhabited island. With 445 residents, it presented numerous novel challenges, resulting in an operation best summarized in 4 words: compromise, commensal, complexity, and cost. A ground-based operation was conducted across the inhabited portion of the island, some 300 ha known as the “settlement,” with aerial bait applied on forested hill country and cliffs (1,200 ha). Initial community resistance and the presence of mice (Mus musculus) meant that almost 19,000 external bait stations were established within the settlement, on a …

Individual And Population Responses To Hydrologic Variability In A Headwater Stream Salamander, Madaline Cochrane

Graduate Student Theses, Dissertations, & Professional Papers

Understanding how organisms respond to environmental variability is a central goal in ecology – a goal made even more pressing by the herculean challenge global climate change presents to all organisms. Climate change is increasing the frequency and intensity of floods and droughts, which will likely have disproportionate effects on freshwater organisms. Many stream-associated species have multi-stage life histories. However, we lack an empirical understanding of life history and movement responses of these organisms to hydrologic disturbances, and how these responses may influence demographic rates. In my dissertation, I used a combination of growth, developmental, movement, and demographic data to …

Defining County-Level Terrestrial Rabies Freedom Using The Us National Rabies Surveillance System: Surveillance Data Analysis, Amber Kunkel, Gabriella Veytsel, Sarah C. Bonaparte, Haillie Meek, Xiaoyue Ma, Amy J. Davis, Jesse Bonwitt, Ryan M. Wallace

United States Department of Agriculture Wildlife Services: Staff Publications

Background: Rabies is a deadly zoonotic disease with nearly 100% fatality rate. In the United States, rabies virus persists in wildlife reservoirs, with occasional spillover into humans and domestic animals. The distribution of reservoir hosts in US counties plays an important role in public health decision-making, including the recommendation of lifesaving postexposure prophylaxis upon suspected rabies exposures. Furthermore, in surveillance data, it is difficult to discern whether counties have no cases reported because rabies was not present or because counties have an unreported rabies presence. These epizootics are monitored by the National Rabies Surveillance System (NRSS), to which approximately 130 …

Deriving Spatially Explicit Direct And Indirect Interaction Networks From Animal Movement Data, Anni Yang, Mark Q. Wilber, Kezia R. Manlove, Ryan S. Miller, Raoul Boughton, James Beasley, Joseph Northrup, Kurt C. Vercauteren, George Wittemyer, Kim Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Quantifying spatiotemporally explicit interactions within animal populations facilitates the understanding of social structure and its relationship with ecological processes. Data from animal tracking technologies (Global Positioning Systems [“GPS”]) can circumvent longstanding challenges in the estimation of spatiotemporally explicit interactions, but the discrete nature and coarse temporal resolution of data mean that ephemeral interactions that occur between consecutive GPS locations go undetected. Here, we developed a method to quantify individual and spatial patterns of interaction using continuous-time movement models (CTMMs) fit to GPS tracking data. We first applied CTMMs to infer the full movement trajectories at an arbitrarily fine temporal scale …