Digital Commons Network^™

Influence Of Landscape Attributes On Virginia Opossum Density, David A. Bernasconi, Wesley C. Dixon, Matthew T. Hamilton, James L. Helton, Richard B. Chipman, Amy T. Gilbert, James C. Beasley, Olin E. Rhodes Jr., Guha Dharmarajan

United States Department of Agriculture Wildlife Services: Staff Publications

TheVirginia opossum (Didelphis virginiana), North America's only marsupial, has a range extending from southern Ontario, Canada, to the Yucatan Peninsula, Mexico, and from the Atlantic seaboard to the Pacific. Despite the Virginia opossum's taxonomic uniqueness in relation to other mammals in North America and rapidly expanding distribution, its ecology remains relatively understudied. Our poor understanding of the ecology of this important mesopredator is especially pronounced in the rural southeastern United States. Our goal was to estimate effects of habitat on opossum density within an extensive multiyear spatial capture‐recapture study. Additionally, we compared the results of this spatial capture‐recapture …

Managing Roof Rats In Citrus Orchards: Initial Efforts Toward Building An Integrated Pest Management Program, Roger A. Baldwin, Justine A. Smith, Ryan Meinerz, Aaron B. Shiels

United States Department of Agriculture Wildlife Services: Staff Publications

Roof rats cause extensive damage in orchards throughout the world. Integrated Pest Management (IPM) systems are the best option for managing rodents, yet few management systems have been developed and tested to control roof rats in agricultural settings. We initiated a study in 2020 to provide the foundation for an IPM program to manage roof rats in California citrus orchards. Our initial efforts centered on developing effective monitoring strategies for roof rats to determine when management actions are needed, assessing rat movement patterns to determine proper placement of management tools, and conducting initial tests of Goodnature A24 self-resetting traps and …

Development Of A Novel Vertebrate Pesticide For The Invasive Small Indian Mongoose, Carmen Antaky, Steven C. Hess, Israel Leinbach, Robert T. T. Sugihara, Emily W. Ruell, Shane Siers

United States Department of Agriculture Wildlife Services: Staff Publications

Small Indian mongooses are detrimental introduced predators in the United States, where they depredate native species, serve as vector of disease, and threaten public safety. Due to the risk of accidental introduction to mongoose-free islands, high cost and limitations to trapping, and no national (Section 3) Environmental Protection Agency (EPA)-registered toxicants for mongoose control, there is a need for an efficacious toxic bait for mongooses for use in conservation areas and at points of entry in the United States. Over the last five years, the National Wildlife Research Center (NWRC) worked to develop a toxic bait for mongooses for registration …

Evidence For Irruptive Fluctuation In Axis Deer Of Hawai‘I, Steven C. Hess, Jonathan Sprague, Jacob Muise

United States Department of Agriculture Wildlife Services: Staff Publications

Axis deer on the Hawaiian Islands of Maui, Lāna‘i, and Moloka‘i simultaneously experienced one of the most dramatic population crashes on record in 2020-2021, which coincided with extended drought conditions and prompted an emergency declaration for these islands. This phenomenon has been anecdotally documented during previous drought events in 2011-2012, but never formally studied. Newspaper articles document abundant deer becoming a nuisance to agriculture and natural resources, and then experiencing high mortality during droughts. This phenomenon fits Caughley’s (1970) operational definition of eruptive (sic) fluctuation “…as an increase in numbers over at least two generations, followed by a marked decline.” …

Abert’S Squirrel Management In Support Of Endangered Mount Graham Red Squirrel Recovery In Arizona, Aaron R. Morehead, Christopher Carillo, Holly Hicks, Wade Sanders, David L. Bergman

United States Department of Agriculture Wildlife Services: Staff Publications

Recovery of the endangered Mount Graham red squirrel (MGRS) will likely be long and challenging. Its limited habitat, isolation to Pinaleño Mountain range, and demographic characteristics restrict its ability to rebound quickly from threats that impact both the squirrel and its habitat. Currently, threats to the MGRS include habitat degradation and loss through high-severity wildfire, fire suppression activities, insect outbreaks, climate change, and human development, and predation, as well as competition with Abert’s squirrels. The most recent wildfire in 2017 impacted over 48,000 acres of already reduced habitat. A critical first step is to protect and manage the remaining population …

Predation Thresholds For Reintroduction Of Native Avifauna Following Suppression Of Invasive Brown Treesnakes On Guam, Robert M. Mcelderry, Eben H. Paxton, Andre V. Nguyen, Shane R. Siers

United States Department of Agriculture Wildlife Services: Staff Publications

The brown treesnake (BTS) (Boiga irregularis) invasion on Guåhan (in English, Guam) led to the extirpation of nearly all native forest birds. In recent years, methods have been developed to reduce BTS abundance on a landscape scale. To help assess the prospects for the successful reintroduction of native birds to Guåhan following BTS suppression, we modeled bird population persistence based on their life history characteristics and relative sensitivity to BTS predation. We constructed individual-based models and simulated BTS predation in hypothetical founding populations for each of seven candidate bird species. We represented BTS predation risk in two steps: …

Migratory Movements And Home Ranges Of Geographically Distinct Wintering Populations Of A Soaring Bird, Ryo Ogawa, J. Brian Davis, D. Tommy King, L. Wes Burger, Bronson K. Strickland, Marsha A. Sovada, Guiming Wang, Fred L. Cunningham

United States Department of Agriculture Wildlife Services: Staff Publications

Migratory soaring birds exhibit spatiotemporal variation in their circannual movements. Nevertheless, it remains uncertain how different winter environments affect the circannual movement patterns of migratory soaring birds. Here, we investigated annual movement strategies of American white pelicans Pelecanus erythrorhynchos (hereafter, pelican) from two geographically distinct wintering grounds in the Southern and Northern Gulf of Mexico (GOM).We hypothesized that hourly movement distance and home range size of a soaring bird would differ between different geographic regions because of different thermals and wind conditions and resource availability. We calculated average and maximum hourly movement distances and seasonal home ranges of GPS-tracking pelicans. …

Toxicity Of The Technology Critical Elements Germanium And Yttrium To Daphnia Magna And Hyalella Azteca And The Influence Of Toxicity Modifying Factors, Rashid Shah

Theses and Dissertations (Comprehensive)

Technology critical elements (TCEs) are increasingly used in high and green technologies but there is little aquatic toxicity data for TCEs, particularly in fresh water. The objective of this study was to investigate the toxicity of two TCEs, Ge and Y, to Daphnia magna and Hyalella azteca and to understand the role of natural organic matter and cations on toxicity modification. Testing followed standard methods. The 48 h EC50 for D. magna was 11.6 (95% CI of 9.64-13.8) mg Ge/L based on measured dissolved concentrations at test end. The addition of NOM at 10 mg DOC/L resulted in a significant …

Athletes’ Perceptions Of Role Significance In An Interdependent Sport Context, Madeline Smith-Ackerl

Theses and Dissertations (Comprehensive)

Roles are integral structural components of interdependent sport teams. The perceptions athletes hold about their role responsibilities influence several individual and team outcomes (Eys et al., 2020). Of specific interest to the current study are athletes’ perceptions of role significance. Two theoretical perspectives dominate research relative to the significance of one’s tasks within organizational psychology: (a) the job characteristic model (JCM; Hackman & Oldham, 1976) and (b) the social information processing model (SIP; Salancik & Pfeffer, 1978). Within the former, task significance (akin to role significance) was conceptualized as the degree to which an employee’s work affects others within or …

2022 State Of Metropolitan Housing Report: Towards A Just Housing Future In Uncertain Times., Lauren Heberle, Kelly Kinahan, Rebecca Halpryn, C. Johnson, M. Neal

Faculty and Staff Scholarship

No abstract provided.

Global In Time Self-Interacting Dirac Fields In The De Sitter Space, Karen Yagdjian

School of Mathematical & Statistical Sciences Faculty Publications

In this paper the semilinear equation of the spin-12 fields in the de Sitter space is investigated. We prove the existence of the global in time small data solution in the expanding de Sitter universe. Then, under the Lochak–Majorana condition, we prove the existence of the global in time solution with large data. The sufficient conditions for the solutions to blow up in finite time are given for large data in the expanding and contracting de Sitter spacetimes. The influence of the Hubble constant on the lifespan is estimated.

Online List Coloring For Signed Graphs, Melissa Tupper, Jacob A. White

School of Mathematical & Statistical Sciences Faculty Publications

We generalize the notion of online list coloring to signed graphs. We define the online list chromatic number of a signed graph, and prove a generalization of Brooks’ Theorem. We also give necessary and sufficient conditions for a signed graph to be degree paintable, or degree choosable. Finally, we classify the 2-list-colorable and 2-list-paintable signed graphs.

Susceptibility Of Wild Canids To Sars-Cov-2, Stephanie M. Porter, Aim E. Hartwig, Helle Bielefeldt-Ohmann, Angela M. Bosco-Lauth, J. Jeffrey Root

United States Department of Agriculture Wildlife Services: Staff Publications

We assessed 2 wild canid species, red foxes (Vulpes vulpes) and coyotes (Canis latrans), for susceptibility to SARS-CoV-2. After experimental inoculation, red foxes became infected and shed infectious virus. Conversely, experimentally challenged coyotes did not become infected; therefore, coyotes are unlikely to be competent hosts for SARS-CoV-2.

Throughout the COVID-19 pandemic, multiple instances of natural infections with SARS-CoV-2 have been reported in pet dogs, likely after exposure to an infected human (1–3). Domestic dogs appear to be minimally susceptible to SARS-CoV-2, as indicated by experimental inoculations resulting in reverse transcription PCR–positive samples and low titer antibody responses but no clinical …

Exploring The Value Of A Global Gene Drive Project Registry, Riley I. Taitingfong, Antoinette J. Piaggio, Cinnamon S. Bloss, Et Al.

United States Department of Agriculture Wildlife Services: Staff Publications

Recent calls to establish a global project registry before releasing any gene-drive-modified organisms (GDOs) have suggested a registry could be valuable to coordinate research, collect data to monitor and evaluate potential ecological impacts, and facilitate transparent communication with community stakeholders and the general public. Here, we report the results of a multidisciplinary expert workshop on GDO registries convened on 8–9 December 2020 involving 70 participants from 14 countries. Participants had expertise in gene drive design, conservation and population modeling, social science, stakeholder engagement, governance and regulation, international policy, and vector control; they represented 45 organizations, spanning national and local governmental …

Lake Huron Shoreline Analysis, Shubham Satish Nandanwar

Theses and Dissertations (Comprehensive)

Lake Huron is a popular tourist destination and is home to several businesses and residents. Since the shoreline is dynamic and is subject to change over the years due to several factors such as a change in water level, soil type, human encroachment, etc., these locations tend to encounter floods due to increased water levels and wind speed. This causes erosion and loss to the properties along the shoreline.

This study is based on two areas of interest named Pinery Provincial Park and Sauble Beach which are located on the shoreline of Lake Huron where Pinery Provincial Park is a …

Exploring Intersectional Factors Associated With Mental Health Service Utilization In A Sample Of Lgbt2q+ Canadians, Samson Tse

Theses and Dissertations (Comprehensive)

The present thesis explores LGBT2Q+ (lesbian, gay, bisexual, transgender (trans), Two-Spirit, queer/questioning, plus) and racialized mental health service utilization within Canada using intersectionality-informed quantitative methodology, separated into additive and multiplicative stages. Data from the 2020 LGBT2Q+ Health Survey (N = 1542) were analyzed using modified Poisson regression. Additive analyses explored mental healthcare utilization as framed by the Andersen Behavioural Model of Healthcare Utilization categories: predisposing, enabling, and need. Results show that predisposing and need factors are more statistically associated with mental healthcare utilization, and that there are distinct intracategorical (within-group) differences in subgroups, particularly between racialized and Indigenous respondents. …

Divest Or Disband?: A Social Problems Game Analysis Of Canadian Media Coverage Of 2020'S Defund The Police Movement, Nicholas Fappiano

Theses and Dissertations (Comprehensive)

Policing in Canada and America has come under the microscope due to several high-profile incidents of police violence against racialized citizens. The murder of George Floyd by officer Derek Chauvin thrust the concept of ‘defund the police’ to the mainstream public dialogue. To date, there are few studies that explore what defund the police means. The present media analysis addresses this research gap by analyzing how Canadian mass media covered the defund police movement. A social constructionist theoretical framework was utilized to analyze 109 newspaper articles on defund the police from The Toronto Star and The Globe and Mail. The …

Feeling Fat: Theorizing Intergenerational Body Narratives Through Affect, Katie Cook

Theses and Dissertations (Comprehensive)

This study set out to understand the intergenerational movement and impact of obesity epidemic and anti-fat narratives that emerged after the 1950s in North America. Embedded in an Anglo-Western, neoliberal context, the current study sought to understand the impact of weight-based messaging on the embodied experiences of parents and their now-adult children. Working within a critical-transformative paradigm and drawing on post-humanism and new materialism, I conducted 19 narrative interviews with individuals born between 1955 and 1990, six of whom were mother-daughter dyads, as well as a body mapping workshop with five self-selecting participants over the course of three sessions. I …

Imagining White Victims And Punishing Black Trauma: Whiteness, Anti-Blackness, Trauma, And Social Work In Canadian K-12 Schools, Christine Mayor

Theses and Dissertations (Comprehensive)

This study critically examined how whiteness and anti-Blackness structure Canadian school social workers’ understanding and responses to students’ expressions of trauma in K-12 schools. Very few studies have previously explored the damage that increasingly popular trauma-engaged school programs may be doing, particularly to Black students. Therefore, this study addressed the role that school social workers play in reproducing harm for racialized, and especially Black, students when implementing trauma-engaged practices.

This critical qualitative study used an innovative methodology combining fictional vignettes and semi-structured interview questions with Ontario school social workers (n=19). Data were analyzed using critical whiteness, anti-Blackness, and critical trauma …

Arctic Stream Characteristics And Diet Analysis Choice Impact Condition And Diet Estimates Of Ninespine Stickleback (Pungitius Pungitius), Adam Kuhrt

Theses and Dissertations (Comprehensive)

Ninespine stickleback (Pungitius pungitius) are ubiquitous in circumpolar freshwaters, but their ecological role is not well understood. Little research has been conducted on the influence of environmental variables on ninespine stickleback in stream environments, and while they are understood to be generalist feeders, their diet in stream environments is equally understudied. Determining diet is difficult due to biases inherent in all standard diet analysis methods. Morphological gut-content analysis (M-GCA), DNA metabarcoding of gut contents (D-GCA), and stable isotope analysis (SIA) are currently three of the most frequently conducted diet analyses; and while combinations of these methods are commonly …

Agents At Work: Modeling How Space Can Influence People In The Workplace, Jovan Poposki

Theses and Dissertations (Comprehensive)

People interact with space in ways that are important to consider when designing an office. Not considering this relationship has led to the dissatisfaction of employees post-occupancy. In this thesis, I present an agent-based model that incorporates several characteristics of agents, such as work ethic and sociability, and explores their behaviours and social interactions in the workplace. The model is first tested on a commercial workspace, varying agent parameters to see how they change the behaviour of the model. I find that agents with extreme personalities are happiest, and show a bimodality in the distribution of time spent in various …

The Effects Of Textured Foot Orthoses On Lower Leg And Plantar Foot Intrinsic Muscle Activity During Walking, Kelly Robb

Theses and Dissertations (Comprehensive)

The global foot orthotic industry was estimated around $3 billion in 2017. Biomechanists and clinical researchers have used foot orthoses (FOs) to study their effects on kinetic, kinematic, and muscle activity, although the mechanisms defining how a FO functions remain unclear. Recently, a neuromotor paradigm has been proposed suggesting that a FO augments the sensory feedback from foot sole skin and subsequently reduces muscle activity while optimizing movement. Although this paradigm currently lacks supporting evidence, neurophysiological research has linked foot sole skin to motorneuron pools of the lower extremity. Furthermore, one potential method of intentionally stimulating sensory feedback from the …

Footwear Characteristics: Effects On Dynamic Balance In The Young And Elderly, Joseph Wallace

Theses and Dissertations (Comprehensive)

Older adults suffer from an increased risk of falling, and falls make up a substantial percentage of injuries and mortality rates in elderly populations. Falls also burden health and long-term care infrastructure and can limit individual independence and overall functioning due to fear of falling. Footwear and orthotic interventions have previously been shown to affect balance in both young and older adult populations and may provide a potential avenue for improving balance and combatting fall rates. Footwear and orthotic interventions are relatively easily implemented, however there is a lack of consistency among current footwear and orthotic literature as well as …

Alpine Shrub Tundra Water Storage And Runoff Dynamics In The Mackenzie Mountains, Sahtú Territory, Nt, Geoffrey Kershaw

Theses and Dissertations (Comprehensive)

Alpine regions receive large volumes of precipitation and are important to local and regional water balances, particularly during baseflow periods of winter cold and summer drought when the larger basin area is frozen and/or water limited. Alpine headwaters in western Canada are expected to warm and receive more precipitation during the coming decades, with implications for groundwater recharge and streamflow generation within these systems and the regional river networks to which they contribute. Throughout the North, thawing peat plateaus and other ice-rich permafrost features are resulting in an increased extent of thermokarst and wetland land cover. This transition places infrastructure …

Coastal Landform Change Influences On Endangered Five-Lined Skink Distribution At Northwest Beach, Point Pelee National Park, Canada, Evan Fortushniok

Theses and Dissertations (Comprehensive)

As park visitation increased to Point Pelee National Park up until its peak in 1963, the installation of infrastructure for the purpose of supporting the recreational interest grew with it. At Northwest Beach, large parking lots were built into the coastal landscape and by the 1970s large areas of sand dunes continued to be heavily impacted by the installation of visitor associated infrastructure. The infrastructure resulted in the stabilization of sand on the beach side of the parking lot, resulting in an artificially stabilized and heavily vegetated dune. Over the last few decades, the park slowly reduced the size and …

'Indirect Pathways Into Practice': Philippine Internationally Educated Nurses And Their Entry Into Ontario's Nursing Profession, Lualhati Marcelino

Theses and Dissertations (Comprehensive)

While there are several studies that highlight the quantitative and statistical profiles of internationally educated nurses (IENs) from the Philippines who migrate to countries throughout Asia, the Middle East, Europe, the United States and Canada, there is little research that delves deeply into the qualitative review and analysis of their experiences in their own words. This study addresses that gap by applying the transnational feminist concept of “global care chains” in a single case study design that explores the experience of nurses who migrated to Ontario through permanent and temporary immigration streams and were interviewed in 2011 to 2012 to …

Impact Of Orthophosphate As A Corrosion Inhibitor And Chloramine Disinfectant On Drinking Water Biofilm Communities, Mitchell Cooke

Theses and Dissertations (Comprehensive)

A drinking water distribution system (DWDS) must maintain conditions within quality standards which assure the effective and safe transport of finished drinking water from treatment plants to the household tap. Although safe to drink, finished water is not sterile, and may contain hundreds of microorganisms in a single milliliter. These microorganisms are present from the source waters, such as lakes, rivers and aquifers, and have passed through early treatment steps. Final treatment steps, such as the maintenance of disinfectant residuals, are used to further minimize viable cells present and focus on the reduction of harmful organisms. Microbial cells entering the …

Political Culture: An Unexplored Factor In Climate Change Diplomacy, Alexander Suen

Theses and Dissertations (Comprehensive)

As climate change continues to ravage the world, mitigation efforts continue to be insufficient to rise to the challenge. Inaction on climate change has been traditionally explained by economic incentives, but some of the variability in climate policies cannot be explained by economics alone. Some variations could be accounted for by the deeply rooted national political culture of Anglo-settler colonies. This political culture may inhibit the willingness of such states to cooperate on climate change. In this dissertation, I describe the political philosophy of the Anglo-settler colony, and the histories of domination of its white settlers over the indigenous peoples …

The Untended Garden: How Adoptees Navigate Relationships With First Family Members, Dawn Michele Mccormick Tracz

Theses and Dissertations (Comprehensive)

This research explores how people who were adopted over the age of 6 years old in open adoption arrangements navigate ongoing relationships with first family members. It explores perceptions of how a connection with both adoptive and first family members impacts self-concept. Using an interpretivist-constructivist lens, the narratives of four women are presented and analyzed. In addition to qualitative interviews, each participant was invited to create images that represented relationships with significant family members. The narratives are re-presented in detail adhering closely to the teller’s organization and emphases. In the analysis, themes related to relationships with first family members and …

Design And Validation Of Artificial Feeders To Study Feeding Preferences And Growth Of Hematophagous Juvenile Sea Lamprey (Petromyzon Marinus), Gracie Li-Ting-Wai

Theses and Dissertations (Comprehensive)

The parasitic and invasive land-locked sea lamprey Petromyzon marinus populations contributed to the collapse of the Great Lakes fisheries in the mid-1900s, while native anadromous populations are currently under threat and require conservation efforts for protection. Despite the increasing concern for both populations of this species, the juvenile stage of the sea lamprey’s life cycle has not been well studied. This is due, in part, to ethical concerns raised around holding live host fish with juveniles and the lack of an alternative feeding method to maintain these juveniles in the laboratory. The feeder should be designed to minimize fouling of …