Graduate Theses & Dissertations


Comparative Evaluation of Effective Population Size Genetic Estimation Methods in Wild Brook Trout (Salvelinus fontinalis) Populations
Effective population size (Ne) is a key concept in population genetics, evolutionary biology and conservation biology that describes an important facet of genetic diversity and the capacity of populations to respond to future evolutionary pressures. The importance of Ne in management and conservation of wild populations encouraged the development of numerous genetic estimators which rely on a variety of methods. Despite the number and diversity of available Ne methods, however, tests of estimator performance have largely relied on simulations, with relatively few tests based on empirical data. I used well-studied wild populations of brook trout (Salvelinus fontinalis) in Algonquin Park, Ontario as a model system to assess the comparative performance of multiple Ne estimation methods and programs, comparing the resultant Ne estimates against demographic population size estimates. As a first step, the genetic diversity and ancestry of wild brook trout populations was determined using 14 microsatellite loci. Genetic structure of brook trout populations showed variable contributions from historical supplemental stocking and also identified localized gene pools within and between watersheds, reflecting variable levels of connectivity and gene flow. Once the genetic ancestry and connectivity of populations had been resolved, single sample (point) and two samples (temporal) genetic estimators were used to estimate Ne of populations with pure native ancestry. Values obtained from genetic estimators utilizing both methods were variable within as well as among populations. Single sample (point) estimators were variable within individual populations, but substantially less than was observed among the temporal methods. The ratios of Ne to the estimated demographic population size (N) in small populations were substantially higher than in larger populations. Variation among estimates obtained from the different methods reflects varying assumptions that underlay the estimation algorithms. This research further investigated the effect of sampling effort and number of microsatellite loci used on Ne values obtained using the linkage disequilibrium (LD) estimation method. Ne estimates varied substantially among values generated from subsets of loci and genotyped individuals, highlighting the necessity for proper sampling design for efforts aiming to measure Ne. Despite the variation observed among and within estimation methods, the Ne concept is a valuable for the conservation and management of both exploited and endangered species. Author Keywords: Brook Trout, Effective population size, Genetic Diversity, Genetic Structure
"Changing our community"
Community-based research (CBR) is a method of discovery that can provide pragmatic methods of advocating for and enabling community change. CBR literature and practice has focused on securing educational and job skills training outcomes for students rather than the communities, and community outcomes CBR and partnership frameworks were truly meant to serve. This research evaluates the effectiveness of a research brokering organization, and the community outcomes that can be meaningfully related back to established partnerships and research. A linked contribution and realist evaluation were employed to consider the contributions of U-Links Centre for Community-Based Research to capacity building in Haliburton County, for host organizations, local municipalities and the public. A community survey (n=65), interviews with past project hosts and management committee members (n=26) anecdotal project exploration, internal document review, and participant observation from living in the region and working within the organization, offers qualitative and quantitative data to support this contribution narrative, while also theorizing key factors for developing projects with high contribution potential. Five key factors were found which can act as both contexts and mechanisms of community-based research mobilization: relevance, relationships, resources, rigour and reach. Author Keywords: capacity building, community, community-based research, contribution analysis, evaluations, research impact
Shorebird Stopover Ecology and Environmental Change at James Bay, Ontario, Canada
I examined how shorebirds respond to environmental change at a key subarctic migratory bird stopover site, the southwestern coast of James Bay, Ontario, Canada. First, I investigated if the morphology of sandpipers using James Bay during southbound migration has changed compared to 40 years prior. I found shorter, more convex and maneuverable wings for sandpipers in the present-day compared to the historical monitoring period, which supports the hypothesis that wing length change is driven by increases in predation risk. Secondly, I assessed the relationship between migration distance, body condition, and shorebird stopover and migratory decisions. Species that travelled farther distances from James Bay to wintering areas migrated with more characteristics of a time-minimizing migration strategy whereas species that travelled shorter distances migrated with energy minimizing strategies. Body condition impacted length of stay, wind selectivity at departure, groundspeeds, and probability of stopover and detection in North America after departing James Bay. Thirdly, I examined annual variation in dry/wet conditions at James Bay and found that shorebirds had lower body mass in years with moderate drought. In the present-day, drought resulted in lower invertebrate abundance and refuelling rates of shorebirds during stopover, which led to shorter stopover duration for juveniles and a higher probability of stopover outside of James Bay for all groups except white-rumped sandpiper. Finally, I estimated the relative importance of intertidal salt marsh and flat habitats to the diets of small shorebirds and found that semipalmated and white-rumped sandpiper (Calidris pusilla and C. fuscicollis) and semipalmated plover (Charadrius semipalmatus) diets consist of ~ 40 – 75% prey from intertidal marsh habitats, the highest documented in the Western Hemisphere for each species. My research shows that James Bay is of high importance to white-rumped sandpipers, which are unlikely to stop in North America after departing James Bay en route to southern South America. Additionally, intertidal salt marsh habitats (and Diptera larvae) appear particularly important for small shorebirds in the region. My thesis shows that changing environmental conditions, such as droughts, can affect shorebird refuelling and stopover strategies. Author Keywords: body condition, diet, environmental change, migration, ornithology, stopover ecology
Genomic architecture of artificially and sexually selected traits in white-tailed deer (Odocoileus virginianus)
Understanding the complex genomic architecture underlying quantitative traits can provide valuable insight for the conservation and management of wildlife. Despite improvements in sequencing technologies, few empirical studies have identified quantitative trait loci (QTL) via whole genome sequencing in free-ranging mammal populations outside a few well-studied systems. This thesis uses high-depth whole genome pooled re-sequencing to characterize the molecular basis of the natural variation observed in two sexually selected, heritable traits in white-tailed deer (Odocoileus virginianus, WTD). Specifically, sampled individuals representing the phenotypic extremes from an island population of WTD for antler and body size traits. Our results showed a largely homogenous genome between extreme phenotypes for each trait, with many highly differentiated regions throughout the genome, indicative of a quantitative model for polygenic traits. We identified and validated several potential QTL of putatively small-to-moderate effect for each trait, and discuss the potential for real-world application to conservation and management. Author Keywords: evolution, extreme phenotypes, genetics, genomics, quantitative traits, sexual selection
Technology of Consent
The 1980s in the United States have come into focus as years of extensive ideological and socioeconomic fracture. A conservative movement arose to counter the progressive gains of previous decades, neoliberalism became the nation’s economic mantra, and détente was jettisoned in favour of military build-up. Such developments materialized out of a multitude of conflicts, a cultural crisis of ideas, perspectives, and words competing to maintain or rework the nation’s core structures. In this dissertation I argue that alongside these conflicts, a crisis over technology and its ramifications played a crucial role as well, with the American public grasping for ways to comprehend a nascent technoculture. Borrowing from Andrew Feenberg, I define three broad categories of popular conceptualization used to comprehend a decade of mass technical and social transformations: the instrumental view, construing technology as a range of efficient tools; the substantive view, insisting technology is an environment that determines its subjects; and a critical approach, which recognizes the capacity for technology to shape subjects, but also its potential to aid new social agendas. Using Feenberg’s categories as interpretive lenses, I foreground these epistemologies in three of the decade’s most popular formations of literary science fiction (sf), and describe the broader discourses they participated in: military sf is connected to military strategy and weapons development (instrumental), cyberpunk to postmodernism and posthumanism (substantive), and feminist sf to feminist theory and politics (critical). These were not just discursive trajectories, I claim, but vital contributors to the material construction of what Antonio Gramsci would call hegemonic and counterhegemonic formations. While the instrumental paradigm was part of the decade’s prevailing hegemonic make-up, substantive and critical discourses offered an alternative to the reality of cowboy militarism and unchecked technological expansion. By engaging with the decade’s texts—from There Will Be War to RoboCop to “A Cyborg Manifesto”—I hope to illuminate what I call the technology of consent, the significance of technological worldviews for modern technocultures, where such views are consented to by subaltern groups, and at the same time the existence of consent itself as a kind of complex social technology in the first place. Author Keywords: American History, Discourse, Hegemony, Science Fiction, Technoculture, Technology
Effects of Invasive Wetland Macrophytes on Habitat Selection by Turtles
Invasive species that alter habitats can have significant impacts on wildlife. The invasive graminoids Phragmites australis (Cav.) Trin. ex Steud, hereafter Phragmites, and Typha × glauca Godr. are rapidly spreading into North American wetlands, replacing native vegetation. Invasive Phragmites is considered a potential threat to several species-at-risk (SAR), including some turtle species. My study wetland contained large stands of Phragmites, as well as Typha spp. (including invasive T. × glauca) that have similar structural traits to Phragmites. To explore the hypothesis that Phragmites and Typha spp. do not provide suitable habitat for turtles, I tested the prediction that turtles avoid Phragmites- and Typha-dominated habitats. I used VHF-GPS transmitters to follow Blanding’s turtles (Emydoidea blandingii, n = 14) and spotted turtles (Clemmys guttata, n = 12). I found that both turtle species did not avoid Phragmites- or Typha-dominated habitats when choosing a home range, or while moving within their home range. I also tested whether the microhabitat selection of Blanding’s turtles and spotted turtles is affected by shoot density of Phragmites, Typha spp., or both. I compared shoot densities of Phragmites and Typha spp. in 4 m2 plots, from locations used by tracked turtles with paired, random locations in these turtles’ home ranges. For both turtle species, the densities of Phragmites and Typha shoots were comparable between used and random locations within the home ranges (generalized linear mixed model; p > 0.05). The use of Phragmites- and Typha-dominated habitats by Blanding’s turtles and spotted turtles suggests that these habitats do not automatically constitute “unsuitable habitats” for turtles. Phragmites and Typha spp. (especially T. × glauca) can replace preferred habitats of some turtle species, and the control of these invasive macrophytes can help to preserve habitat heterogeneity. However, the presence of SAR turtles in Phragmites and Typha spp. stands should inform risk-assessments for invasive plant species control methods that include mechanical rolling of stands, where heavy machinery might encounter turtles. Author Keywords: Blanding’s turtles, compositional analysis, habitat selection, Phragmites australis, spotted turtles, Typha x glauca
Relationship Between Precarious Employment, Behaviour Addictions and Substance Use Among Canadian Young Adults
This thesis utilized a unique data-set, the Quinte Longitudinal Survey, to explore relationships among precarious employment and a range of mental health problems in a representative sample of Ontario young adults. Study 1 focused on various behavioural addictions (such as problem gambling, video gaming, internet use, exercise, compulsive shopping, and sex) and precarious employment. The results showed that precariously employed men were preoccupied with gambling and sex while their female counterparts preferred shopping. Gambling and excessive shopping diminished over time while excessive sexual practices increased. Study 2 focused on the association between precarious employment and substance abuse (such as tobacco, alcohol, cannabis, hallucinogens, stimulants, and other substances). The results showed that men used cannabis more than women, and the non-precarious employed group abused alcohol more than individuals in the precarious group. This research has implications for both health care professionals and intervention program developers when working with young adults in precarious jobs. Author Keywords: Behaviour Addictions, Precarious Employment, Substance Abuse, Young Adults
Struggling for a New Left
This study examines the emergence of the New Left organization, The New Tendency, in Windsor, Ontario during the 1970s. The New Tendency, which developed in a number of Ontario cities, represents one articulation of the Canadian New Left’s turn towards working-class organizing in the early 1970s after the student movement’s dissolution in the late 1960s. Influenced by dissident Marxist theorists associated with the Johnson-Forest Tendency and Italian workerism, The New Tendency sought to create alternative forms of working-class organizing that existed outside of, and often in direct opposition to, both the mainstream labour movement and Old Left organizations such as the Communist Party and the New Democratic Party. After examining the roots of the organization and the important legacies of class struggle in Windsor, the thesis explores how The New Tendency contributed to working-class self activity on the shop-floor of Windsor’s auto factories and in the community more broadly. However, this New Left mobilization was also hampered by inner-group sectarianism and a rapidly changing economic context. Ultimately, the challenges that coincided with The New Tendency’s emergence in the 1970s led to its dissolution. While short-lived, the history of the Windsor branch of The New Tendency helps provide valuable insight into the trajectory of the Canadian New Left and working-class struggle in the 1970s, highlighting experiences that have too often been overlooked in previous scholarship. Furthermore, this study illustrates the transnational development of New Left ideas and organizations by examining The New Tendency’s close connections to comparable groups active in manufacturing cities in Europe and the United States; such international relationships and exchanges were vital to the evolution of autonomist Marxism around the world. Finally, the Windsor New Tendency’s history is an important case study of the New Left’s attempts to reckon with a transitional moment for global capitalism, as the group’s experiences coincided with the Fordist accord’s death throes and the beginning of neoliberalism’s ascendancy. Author Keywords: Autonomist Marxism, Canada, Labour, New Left, Rank-and-file Organizing, Working-Class History
Bringing Knowledges Together
The natural world and environmental issues present critical points of convergence between Indigenous and non-Indigenous people and their knowledge systems. This qualitative study engaged with 18 Indigenous and non-Indigenous environmental practitioners in interview conversations to explore their experiences in cross-cultural environmental collaborations. The research undertakes a complexity theory approach to answer the following research questions: 1.a) What skills, values, knowledges and approaches do environmental practitioners need to enable Western and Indigenous knowledge systems to come together in addressing environmental challenges? 1. b) What does effectiveness and/or success look like in cross-cultural environmental collaboration? 2. How can post-secondary and professional development educational programs impart the skills, values, knowledges and approaches that their students need to effectively engage in work that brings together Indigenous and non-Indigenous people and their knowledge systems in addressing environmental challenges? This study applied multiple lenses to analyze and interpret the data. The author’s own reflections as both a practitioner and researcher working and teaching in crosscultural environmental contexts were a central component of the study. Through this analysis a set of skills, values, knowledges, approaches, attributes, and roles emerged. The findings reaffirm the importance of respect, relationship, responsibility, and reciprocity as central values in Indigenous praxis and identify additional values. The application of a critical theory lens illuminated that subtle racism and microaggressions influence environmental collaboration between Indigenous and non-Indigenous people. The study proposes a curriculum and program design for post-secondary and professional development contexts, that draws upon multiple pedagogies to prepare learners to work cross-culturally in respectful ways. These findings are relevant to environmental practitioners currently working in the field and contribute to a further articulation of an emerging Indigenous Environmental Studies and Sciences (IESS) pedagogy. Author Keywords: Cross-cultural collaboration, Curriculum Development, Environmental Education, Indigenous Studies, Professional Development
Development of a Digital Comparative Collection of Chert Types in Ontario and the Evaluation of Change in Accuracy and Confidence of Chert Type Identifications
The objective of this thesis is to create a foundation for a digital comparative collection of chert types found on archaeological sites in Ontario, both local and non-local varieties, and to evaluate the impact of a digital reference collection on the confidence and accuracy of the user in comparison to hard copy guides or hand samples that are more often traditionally used. Spatial and temporal variation in the use of different lithic raw materials has shown to provide insight into cultural interaction, resource exchange and control across multiple periods in the study of Indigenous archaeology; however comparative collections needed to conduct analyses remain accessible only in a physical form. This study will build a foundation, develop a prototype using a represented sample of hand specimens from the William Fox Northeastern North American Lithic Reference Collection (referred to hereafter as The Fox Collection) at Trent University, and create a prototype digital system to assist the user in identifying the chert type through the use of a simple expert system using a decision tree. The digital identification system was tested by a group of volunteers with to compare accuracy and confidence in analysis against traditional methods of hand samples and hard copy guides. When supplied with the digital reference collection, a statistically significant improvement in the accuracy and confidence of chert identification was identified. Author Keywords: database design, digital comparative collection, digital identification system, expert system, Ontario archaeology, raw material analysis
Behavioural ecology and population dynamics of freshwater turtles in a semi-urban landscape at their northern range limit
Species are faced with a variety of challenges in the environment, including natural challenges, such as variability in ambient temperature, and anthropogenic threats, such as habitat transformation associated with urbanisation. Understanding how animals respond to these kinds of challenges can advance the field of behavioural ecology and guide management decisions for wild species. Yet, we still have limited understanding of the extent of natural and human-caused impacts on animal behaviour and population dynamics, and lack robust assessment of behaviour in free-ranging animals. Using novel miniaturised biologging technologies, I characterised and validated behaviour in two freshwater turtle species: Blanding’s turtles (Emydoidea blandingii) and Painted turtles (Chrysemys picta). Further, I investigated how these two ectothermic species navigate a thermally heterogeneous landscape near their northern range limit, by comparing selected and available ambient temperatures. I showed that turtles preferred locations that were, on average, warmer and less variable in temperature than the available environment, and that this thermal sensitivity was greatest early in the year, and at fine spatial scales that likely matched the species' perception of the environment. Lastly, I assessed whether urban development was compatible with long-term viability of a Blanding’s turtle population, by monitoring habitat change and turtle survival over one decade of ongoing residential and road development. I found that Blanding’s turtle habitat quantity and connectivity declined in the area, which coincided with high road mortality and severe declines in turtle survival and population size, especially in adult females. I concluded that urban development and current road mortality rates are incompatible with the long-term viability of this at-risk turtle population. Overall, my findings demonstrate the importance of variation in the thermal environment and anthropogenic impacts on habitat in shaping the behaviour and population dynamics of this species-at-risk. Author Keywords: animal behaviour, biologging, ectotherms, habitat selection, temperature, urbanisation
origin and ecological function of an ion inducing anti-predator behaviour in Lithobates tadpoles
Chemical cues are used commonly by prey to identify predation risk in aquatic environments. Previous work has indicated that negatively-charged ions of m/z 501 are possibly a kairomone that induces anti-predator responses in tadpoles. This thesis found that this ion species: (i) is produced by injured tadpoles; (ii) exhibits increased spectral intensity with higher tadpole biomass; and (iii) is not produced by starved predators. These results refute the hypothesis that the ion is a kairomone, and rather support its role as an alarm cue released from tadpoles. High resolution mass spectrometry (HR-MS) revealed a unique elemental composition for [M-H]-, m/z 501.2886, of C26H45O7S-. Collision induced dissociation (CID) of ion m/z 501 formed product ions of m/z 97 and m/z 80, HSO4- and SO3-, respectively, indicating the presence of sulfate. Green frog (Lithobates clamitans) tadpoles exposed to m/z 501, and an industrial analogue, sodium dodecyl sulphate (NaC12H25O4S), exhibited similar anti-predator responses, thereby suggesting the potential role of organic sulfate as a tadpole behavioural alterant. Author Keywords: Alarm cue, Amphibian, Chemical Ecology, Mass spectrometry, Predator-prey interactions


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