Graduate Theses & Dissertations

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Fall Migratory Behaviour and Cross-seasonal Interactions in Semipalmated Plovers (Charadrius semipalmatus) Breeding in the Hudson Bay Lowlands, Canada
I used the Motus Wildlife Tracking System to monitor the fall migration behaviour and assess the underlying drivers of migration strategy in a small shorebird, the Semipalmated Plover (Charadrius semipalmatus), breeding at two subarctic sites: Churchill, Manitoba and Burntpoint Creek, Ontario, Canada. Semipalmated Plovers from both sites departed breeding areas between mid-July and early August, with females preceding males and failed breeders preceding successful breeders. Migrants showed between and within-population variation in migration behaviour, though birds from both sites tended to follow interior or coastal routes and congregated in three major stopover regions along the mid-Atlantic coast of North America. I found that later-departing birds had initial flight tracks oriented more toward the south, faster overall ground speeds, were less likely to stopover in North America, and stopped at lower latitudes, suggesting that later-departing individuals use aspects of a time-minimizing strategy on fall migration. My findings emphasize the importance of the mid-Atlantic coast for Semipalmated Plovers and establish connectivity between sites used during breeding and migration. Author Keywords: Breeding, Migration, Motus, Semipalmated Plover, Shorebird, Stopover
Food insecurity among racialized international students
The notion that food insecurity only occurs in the absence of food is prevalent in society. This perception is too narrow and insufficient to capture the diverse manifestations and experiences of food insecurity. In this thesis, I adopt a more expansive approach to examine food (in)security through the lenses of adequacy, quality, and availability of culturally relevant food. I look specifically at the experiences of racialized international students from diverse backgrounds, to empirically ground this approach to understanding food (in)security. Drawing on both quantitative and qualitative data, this study explores the perceptions and real-life experiences of racialized international students who study at Trent University and University of Toronto. These two institutions were selected based on cultural diversity and variation, proximity to culturally appropriate food and the cost involved in accessing culturally appropriate food. Beyond that, I examine structural and policy elements that may be exacerbating the challenge of food security among this category of students. Clearly, issues related to food insecurity and hunger within all spatial configurations are urgent, however, there is a scarcity of literature that zeroes in on the experiences of racialized international students specifically. In the wake of the dramatic internationalization of post-secondary Canadian schools, issues of foreign students’ welfare cannot be overlooked, hence, I narrowed my research lenses to study the character of racialized international students’ inadequate access to culturally appropriate food. Upon analyzing the survey data gathered from 107 racialized international students coupled with semi-structured in-depth interviews with 8 racialized students, I found evidence that culturally appropriate foodstuffs were not abundant in supply for racialized international students. Consequently, the low supply of this category of foodstuffs translates into higher levels of prices which deter racialized international students from making adequate purchases to meet their taste and preference. As part of the findings, the students mentioned that the high cost of tuition, as well as other school-related expenditures are structural policy barriers that leave them with meagre amounts of income to spend on culturally appropriate food items. Under such circumstances, racialized international students are left with the option of purchasing fewer quantities of culturally relevant foodstuffs that meet their daily nutritional requirements. The study further revealed that the challenge of food insecurity poses a threat to the academic achievement and psycho-social well-being of affected students. In addressing these challenges, I propose that the government as well as the school authorities should consider reducing the tuition fees to lessen the financial burden on students. Apart from that, stocking grocery stores and creating culturally appropriate food supply centers in and around school campuses may be helpful. Also, the international offices of universities should intensify welfare programs that entail periodic needs assessment of international students. This will offer the school authorities timely support services to students as and when it is needed. In conclusion, I wish to state that this study seeks to add to the recently growing strand of literature that examines the intersectionality between internationalization of post-secondary schools and food insecurity. The findings provide important and preliminary evidence underpinning the experiences of racialized international students with the phenomenon of food insecurity, thereby providing a point of departure for additional research on the broader nature of intersections between food insecurity and racialization. Author Keywords: Canada, Culture, Food insecurity, International Students, Race, Universities
Using the Same Language, but Meaning Different Things
Two dominant narratives emerging throughout the war were the national narrative––that is, the narrative of the war as articulated by the British nation via texts such as political speeches, recruitment posters, and popular music–– and the poetic narrative––that is, the narrative of the war emerging from poets, specifically battlefront poets for the sake of this thesis. One hundred years since World War One, these two narratives are often conceptualized as mutually exclusive, even antithetical to one another. This thesis brings these diverse narratives into conversation with one another by investigating how they both draw on the same rhetorics and yet use these rhetorics to differing ends. Interestingly, the rhetorics employed by both narratives throughout the war endure in contemporary remembrance practices in Britain today. By investigating how each narrative draws on and employs the same rhetorics, this thesis both contextualizes and complexifies contemporary interpretations of contemporary remembrance practices. Author Keywords: Battlefront Poetry , Britain, Narrative, Remembrance, Rhetoric, World War One
Expression of Giardia intestinalis flavoenzyme GiOR-1 and characterization of its electron transfer properties
Giardia intestinalis possesses four isotypes of cytochrome b5 (gCYTB-I-IV) that differ from their mammalian counterparts, suggesting different functions in this protozoan parasite. Although the recently discovered Giardia flavoenzyme, GiOR-1, reduces these cytochromes, its properties have not been thoroughly studied, owing to the difficulty in its expression. Here I describe successful conditions for expression of GiOR-1 using autoinduction. GiOR-1 is obtained with flavins bound as indicated by its UV-visible spectrum. Its ability to catalyze electron transfer from donors (NADH, NADPH) to acceptors (oxygen, ferricyanide, cytochrome c, gCYTB5-III) were studied in spectrophotometric rate assays. NADPH is the preferred electron donor, while cytochromes are the preferred electron acceptors. Interestingly, the His-tag used to purify gCYTB5-III decreases its reaction rate with GiOR-1, as an untagged version has slightly faster rates. These findings establish the appropriate conditions for further studies on GiOR-1, including the identification of endogenous electron acceptors. Author Keywords: Autoinduction, Cytochrome b5, Cytochrome P450 oxidoreductase, Giardia intestinalis, GiOR-1, Polyhistidine tag
Prey abundance and habitat during the breeding season for Piping Plovers in the Ontario Great Lakes region
Similar to other shorebird trends around the world, the Piping Plover population (Charadrius melodus circumcinctus) is projected to decline if concerted conservation efforts are relaxed. To date, there is insufficient understanding of the connection between habitat type, prey abundance, and chick behaviour of the Piping Plover breeding population in Ontario. The aim of my thesis was to gain knowledge about prey abundance at recent and historic breeding locations, understanding how habitat influences prey abundance and chick behaviour across the Piping Plover breeding range in Ontario’s Great Lakes. The objective of my first study was to understand prey abundance across the breeding region Great Lakes of Ontario from 2018-2019, including occupied and unoccupied sites, and to quantify variation among habitats and periods of reproduction. To evaluate resources, I sampled 17 locations to compare prey abundance using invertebrate traps (n= 3,507). Sampling took place over the reproductive periods of nest initiation, post-hatch, and fledging and in four habitat types of shoreline, wrack, berm, and back dune. Occupied breeding sites had higher prey abundances, and different assemblages of invertebrate prey than unoccupied sites. Additionally, breeding sites had higher prey abundance during nest initiation and supported higher amounts of prey in shoreline and wrack habitat. The objective of my second study was to understand how habitat types influence chick behaviour. To evaluate behaviour-habitat trends, instantaneous chick observations were recorded at the four nest sites from the post-hatch to fledging stages. In total there were 23 fledged chicks that we observed across the two years. Chicks in this study spent 60.9% of their time foraging, 11.9% of the time displaying alert behaviour, 21.4% of their time resting or being brooded, and 5.9% of their time preening. Chicks spent a large proportion of time foraging in the shoreline, resting in the back dune, and alert in berm habitat. The frequency of these alert, defensive behaviours differed among sites, with Sauble Beach chicks spending more time in defensive behaviours compared to other sites. I concluded that in both nesting and brood-rearing periods, habitat is selected non-randomly by adult and young Piping Plovers to maximize access to invertebrate prey for growth and survival. Access by chicks to the most productive habitats should be considered in local management decisions. Author Keywords: chick behaviour, endangered, Great Lakes Region, habitat, Piping Plovers, prey abundance
Wetland Offsetting
Wetland loss in southern Ontario, escalated by development, is putting pressure on planners as they struggle to meet development needs while maintaining a balance with regional natural heritage. Wetland offsetting, coupled with strategic environmental assessment and sustainable community planning, offers a potential solution. A combined approach of literature review, interviews, focus group, and case study with Central Lake Ontario Conservation Authority (CLOCA) allowed me to present experiences and perspectives on wetland offsetting, site selection methods, and ecosystem service priorities. The focus group looked at organizational interactions and decision-making processes during wetland offsetting. Research resulted in creation of the Strategic Wetland Offset Site Selection Score Card (SWOSSS Card). Five of CLOCA’s past offsetting projects were reviewed to see what worked and what did not. Findings determined that use of strategic wetland offset site selection tools have the potential to provide an efficient means to quantify offsetting risk ahead of restoration efforts. Author Keywords: compensation, landuse planning, offsetting, prioritization, restoration, wetlands
Sensitivity of Forest Soils to Acidic Deposition Downwind of an Aluminum Smelter, Kitimat, B.C.
Maximum permitted SO2 emissions from an aluminum smelter in Kitimat, B.C., increased after modernization in 2015. An increase in acidic deposition can potentially acidify forest soils. Monitoring was conducted at two long-term soil monitoring plots at near (7 km) and far (41 km) sites downwind from the smelter. Change in soil properties was assessed between 2015 and 2018: for the near plot, there was significant decrease in pH and exchange acidity; far plot soils exhibited significant decrease of base cations and exchange acidity in the 0–5 cm layer only. The average total SO42- deposition at near and far plots were estimated to be between 8.2–12.1 and 6.7–7.4 kg/ha/yr, respectively. It was concluded no soil acidification was detected. Observed changes were attributed to measured differences in organic matter, likely influenced by sampling difficulty and measurement process discrepancies. Estimated SO42- deposition levels pose no risk to soil base cation depletion. Author Keywords: acid forest soils, acidic deposition, aluminum smelter, exchangeable base cations, long-term monitoring, minimum detectable change
Assessing effects and fate of environmental contaminants in invasive, native, and endangered macrophytes
Macrophytes play an important role in aquatic ecosystems, and thus are integral to ecological risk assessments of environmental contaminants. In this dissertation, I address gaps in the assessments of contaminant fate and effects in macrophytes, with focus on glyphosate herbicide use for invasive plant control. First, I evaluated the suitability of Typha as future standard test species to represent emergent macrophytes in risk assessments. I concluded that Typha is ecologically relevant, straight-forward to grow, and its sensitivity can be assessed with various morphological and physiological endpoints. Second, I assessed effects from glyphosate (Roundup WeatherMAX® formulation) spray drift exposure on emergent non-target macrophytes. I performed toxicity tests with five taxa, Phragmites australis, Typha × glauca, Typha latifolia, Ammannia robusta, and Sida hermaphrodita, which in Canada collectively represent invasive, native, and endangered species. I found significant differences in glyphosate sensitivity among genera, and all species’ growth was adversely affected at concentrations as low as 0.1% (0.54 g/L), much below the currently used rate (5%, 27 g/L). Third, I assessed the potential for glyphosate accumulation in and release from treated plant tissues. I found that P. australis and T. × glauca accumulate glyphosate following spray treatment, and that accumulated glyphosate can leach out of treated plant tissues upon their submergence in water. Finally, I assessed effects of released glyphosate on non-target macrophytes. I found that P. australis and T. × glauca leachate containing glyphosate residues can stimulate the germination and seedling growth of T. latifolia, but can exert an inhibiting effect on A. robusta, although leachate without glyphosate caused similar responses in both plants. Additionally, I found no negative effects in A. robusta when exposed to glyphosate residues in surface water, or when grown with rhizosphere contact to an invasive plant that was wicked (touched) with glyphosate. My results show that non-target macrophytes can be at risk from glyphosate spray for invasive plant control, but risks can be mitigated through informed ecosystem management activities, such as targeted wick-applications or removing plant litter. Integrating contaminant fate and effect assessments with emergent macrophytes into ecological risk assessments can support the protection of diverse macrophyte communities. Author Keywords: Ecosystem management, Ecotoxicology, Glyphosate, Herbicide, Invasive plant, Species at risk
Robust assessment of changes in wild mammal occupancy and activity relative to livestock and human disturbance
Anthropogenic activities such as human activity and livestock grazing are responsible for the global rise in disturbance impacts on wildlife and may underlie regional changes in biodiversity and ecosystem dynamics. Few studies have tried to disentangle the effects of different anthropogenic activities on wildlife behaviour, leaving a major gap in our understanding of conservation and management needs in disturbed areas. Human activity and livestock grazing are increasing in spread and intensity worldwide, thereby imposing pressure on both wildlife and natural areas. In this thesis, I used a camera trapping and occupancy modeling framework to assess whether human presence and livestock grazing had different impacts on site occupancy and activity of 10 wild mammal species, and how responses differed across taxa. Specifically, I predicted that all species would be sensitive to disturbance, but the type and intensity of the response would depend on disturbance type. I detected different responses to each disturbance type across species, but response type (displacement, activity change, crepuscularity) was not associated with species characteristics such as body. Importantly, disturbance intensity had a strong effect on wildlife activity levels, with many species exhibiting marked reductions in activity at high human or livestock disturbance intensity. It remains unclear whether all species’ responses are a direct consequence of disturbance versus indirect outcomes of shifts in behaviour of other species in the wildlife community (i.e., disturbance-related changes in prey activity may affect predator activity). Although on the whole disturbance intensity and effect sizes tended to be relatively low in this study, responses were exhibited across all species, implying that disturbance responses may be universal in wild mammals and largely underestimated. Ultimately, my work offers a template for the robust assessment of disturbance impacts on wildlife and provides new avenues for future research to deepen our understanding of wildlife sensitivity to anthropogenic activities. Author Keywords: activity, anthropogenic disturbance, human activity, livestock, occupancy, wildlife
Rethinking Subjectivity
The following thesis problematizes different theories of subject formation in relation to morality, accountability, and consciousness raising. Focusing on the conditions subjects emerge in, I argue that socially transformative subjectivities emerge in movement through spaces. The theoretical discussion departs from the premise that morally accountable subjectivities drive social change. The politics of positionality that anchor the subject in a particular social location conceptualize morality as the result of critical consciousness raising. The causal nature of the relationship between the subject’s ability to reflect back on itself and its moral capacity is problematic for it leaves the reflective subject in a position of epistemic and moral authority. Rather, a subject who does not fully know itself nor the conditions of its being has the ability to engage in moral inquiry. Grounding subject formation in epistemic uncertainty construes the subject as inherently accountable to other unknowing subjects. Transformative subjectivities emerge out of epistemic resistance and uncertainty. The particular understanding of morality that underlies the rethinking of my moral subject emanates from its relational constitution. A morality of care prioritizes the responsibilities a subject has to others. In the context of Covid-19, relational subjects act in accordance with a morality of care that leads them to intervene in the lives of others who are threatened by the virus and left unprotected by institutional structures. The desire to interfere is cultivated when subjects emerge in ontological fields generated through epistemic intervention. One way to create such interventions is through counter-hegemonic cultural production such as works of art. Author Keywords:
Desire to be Zine
This thesis explores access to feminist zine culture and community, specifically if, and how, access has been altered in the age of digital technologies and increased access to digital spaces. Results from a questionnaire completed by 8 young feminist zine-makers and readers of marginalized genders indicated that though the modern boundaries of what a zine is has been expanded to include e-zines, there remains a preference toward print zines in zine-making and reading practices. Results also revealed that while there is a preference toward accessing feminist zine culture and community in-person in theory, participants were more likely to access feminist zine culture and community online in reality. This project found that digital technologies and the Internet have affected feminist zine culture in multiple ways, ranging from the Internet creating a new access points to community, to the Internet making it easier to find, purchase, and distribute zines. Author Keywords: Digital Media, Feminism, Feminist Zine Culture, Feminist Zines, Materiality, Print Media
An assessment of the determinants of, or barriers to, successful municipal food waste management systems
Food waste (FW) disposal has negative implications for the social, economic, and environmental sustainability of communities. While some municipalities in Canada have made improvements to their FW management, others have not been successful. Considering the complexity of the issues integrated into municipal FW management (MFWM), a mixed methodological approach was used to understand the determinants of, or barriers to, successful MFWM systems. Methods included analysis of primary data from a household survey with a fixed response and open-ended questions, along with analysis of the secondary literature. A comparative analysis of the results was undertaken to determine similarities and differences between successful and less successful cases (Guelph and London, Ontario, respectively) and the broader empirical literature. The results suggest the success of MFWM is determined by the commitment of political decision-makers to implement FW policies backed by adequate regulations, high levels of perceived behavioural control over barriers to participating in MFWM programs, and the ability to finance user-friendly MFWM infrastructure. Recommendations are made to guide policies and programming on food waste management. Author Keywords: Components of Waste management System , Composting, Determinants of Success, Food Waste Reduction, Households Food Waste Behaviour, Municipal Food Waste Management System

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