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USE OF SALIVARY CORTISOL TO EVALUATE THE INFLUENCE OF RIDES ON THE STRESS PHYSIOLOGY OF DROMEDARY CAMELS (CAMELUS DROMEDARIUS): VALIDATION OF METHODS AND ASSESSMENT OF SALIVA STORAGE TECHNIQUES

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Creator (cre): Majchrzak, Yasmine Nicole, Thesis advisor (ths): Burness, Gary, Degree committee member (dgc): Mastromonaco, Gabriela, Degree committee member (dgc): Murray, Dennis, Degree committee member (dgc): Bowman, Jeff, Degree granting institution (dgg): Trent University
Abstract:

Many facilities attempt to alleviate the risk of chronic stress in captivity by providing environmental enrichment shown to minimize behavioural disorders and stress in several species. One potential form of enrichment used in zoos is training animals to perform rides for guests, however, the effect of this activity on the welfare of individual animals has never been examined. I validated the use of saliva for assessing stress in dromedary camels (Camelus dromedarius) an animal commonly used for rides. I then measured variation in salivary cortisol in four male camels during animal rides for guests at the Toronto Zoo. The camels were sampled during the ride season (from June to August) using four treatments: 1) in their pasture, 2) at the ride area not performing rides, 3) performing a low number of rides (n=50/day) and 4) performing a high number of rides (n=150/day). Furthermore, samples were taken before and after the ride season for comparison. There was a significant difference between the post-ride season treatment and the three treatments involving guest presence during the ride season (ride area, low rides, high rides. This indicates that performing rides is not a stressful experience based on the stress metrics I used, and suggests that rides may be a form of enrichment for dromedary camels.

Author Keywords: ACTH challenge, animal welfare, camels, environmental enrichment, salivary cortisol, stress

2014

ASSESSING THE IMPACT OF ATMOSPHERIC DEPOSITION AND HARVEST INTENSITY ON SOIL ACIDITY AND NUTRIENT POOLS IN PLANTATION FORESTS

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Creator (cre): Johnson, James Anthony, Thesis advisor (ths): Aherne, Julian, Degree committee member (dgc): Watmough, Shaun A, Degree committee member (dgc): Huber, Christian, Degree committee member (dgc): Cummins, Thomas, Degree granting institution (dgg): Trent University
Abstract:

The objective of this thesis was to assess the influence of anthropogenic sulphur (S) and nitrogen (N) deposition, and harvesting on soil acidity and calcium (Ca2+), magnesium (Mg2+), potassium (K+) and N soil pools in plantation forest soils in Ireland. The response to reductions in anthropogenic S deposition was assessed using temporal trends in soil solution chemistry at two long-term monitoring plots--one on a blanket peat, the other on a peaty podzol. At the peat site, there was little evidence of a response to reductions in throughfall non marine sulphate (nmSO42-) and acidity; soil water acidity was determined by organic acids. In addition, temporal variation in soil water did not respond to that in throughfall. In the podzol, reductions in anthropogenic S and H+ deposition led to a significant improvement in soil water chemistry at 75 cm; pH increased and total aluminum (Altot) concentrations declined. The impact of harvest scenarios on exchangeable Ca2+, Mg2+ and K+ pools was assessed using input-output budgets at 40 sites (30 spruce, 10 pine). Harvest scenarios were stem-only harvest (SOH), stem plus branch harvest (SBH) and stem, branch and needle harvest (whole-tree harvesting; WTH). Average K+ and Mg2+ budgets were positive under these scenarios. However, exchangeable K+ pools were small and due to uncertainty in K+ budgets, could be depleted within one rotation. Average Ca2+ budgets for spruce were balanced under SOH, but negative under SBH and WTH. Nitrogen deposition was high, between 5 and 19 kg N ha-1 yr-1, but was balanced by N removal in SOH. However, N budgets were under SBH and WTH, indicating that these harvesting methods would lead to depletion of soil N over the long-term. Finally, monitoring of N cycling at a spruce plot indicated that N deposition was contributing to large NO3- leaching, and as such the site was N saturated. However, N cycling did not fit the criteria of the N saturation hypothesis; instead leaching was directly related to N deposition and supported the model of kinetic N saturation.

Author Keywords: acidic deposition, base cations, input-output budgets, Ireland, nitrogen, whole-tree harvesting

2014

Unexpected Journeys: Unmasking Home While Abroad

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Creator (cre): Jordan, Bryan, Thesis advisor (ths): Harrison, Julia, Degree committee member (dgc): Wright, Robert, Degree granting institution (dgg): Trent University
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The last two decades have seen thousands of Canadian university graduates go to teach English in places such as China, South Korea, and Japan. In this thesis, drawing on Clandinin and Connelly's concept of narrative inquiry, I situate the stories I heard about the experiences of 15 teachers who taught English as a Second Language in South Korea between 2003 and 2012.

While my interviewees expressed intrinsically personal reasons for taking on such temporary professional employment, they also acknowledged that they felt somewhat forced to do so by an increasingly bleak job market at home. I position their decisions in the neoliberal employment context in Canada over the past two decades, highlighting the personal and socioeconomic factors that influenced them to take up such opportunities. Additionally, I examine how these experiences shifted their views of Canada and what it meant to be Canadian, both while they were away and upon their return home by revealing the contradictions between expectation and the lived realities of young Canadians. These contradictions unmask the deceptive nature of dominant narratives in Canadian society.

Author Keywords: Canadian Identity, Canadian Job Market, Narrative, Neoliberalism, Teaching Abroad

2014

The Return to "The Child": Nature, Language and the Sensing Body in the Poetry of Mary Oliver

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Creator (cre): Holtz Braeckman, Erin Marie, Thesis advisor (ths): Steffler, Margaret, Degree committee member (dgc): Eddy, Charmaine, Degree committee member (dgc): Bode, Rita, Degree granting institution (dgg): Trent University
Abstract:

Despite - or perhaps because of - her popularity as a best-selling poet, the work of Mary Oliver has been minimized and marginalized within the academy. Nevertheless, Oliver's readership is an expansive and devout one made up of a wired yet insular North American public in search of reconnecting with the natural world. I propose that through Oliver's poetry readers access the affective, sensory responses to nature first encountered during childhood. This return to "the child" is deliberately used by various publics to share communal goals. Drawing from such frameworks as ecocritical and trauma theory, I explore environmental memory, ecstatic places, and the sensuousness of nature and language to consider ways in which diverse publics claim and use Oliver's work. I provide a close reading of selections of Oliver's poems to argue that her work's appeal speaks to a revived perception of the necessity of nature to the human spirit

Author Keywords: Attentiveness, Childhood, Language, Mary Oliver, Nature Poetry, Senses

2013

The Role of Multiple Nights of Sleep in the Consolidation of an Engaging and Complex Motor Learning Task

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Creator (cre): Higginson, Caitlin, Thesis advisor (ths): Peters, Kevin R, Degree committee member (dgc): Smith, Carlyle T, Degree committee member (dgc): Brown, Liana E, Degree granting institution (dgg): Trent University
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The present study examined the role of multiple nights of sleep in the consolidation of a complex motor learning task. Participants were 24 Trent undergraduates, 12 in the learning group (Mage = 20.33, SD = 1.87, 10 female) and 12 in the control group (Mage = 21.92, SD = 3.42, 7 female). Participants underwent 5 consecutive nights of polysomnographic recordings, with a Rock Band learning session on the third night. A series of 2(group)x4(night) ANOVAs were performed on the sleep variables. Interactions were found in the number of spindles detected at Pz, F(333) = 9.19, p <.01, and in the density of spindles detected at Pz, F(3,33) = 4.06, p <.05. The pattern of changes from baseline was significantly different between the two groups; spindles increased in the learning group and decreased in the control group. The novel finding was that spindle number/density remained elevated at the third post-learning night of sleep.

Author Keywords: Motor Learning, Procedural Memory, Sleep, Sleep Spindles

2014

THE EFFECTS OF ROTATIONAL GRAZING AND HAY MANAGEMENT ON THE REPRODUCTIVE SUCCESS OF BOBOLINK AND EASTERN MEADOWLARK IN EASTERN ONTARIO

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Creator (cre): MacDonald, Nicole Marlene, Thesis advisor (ths): Nol, Erica, Degree committee member (dgc): Nocera, Joseph J, Degree committee member (dgc): Beresford, David V, Degree granting institution (dgg): Trent University
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I investigated the impact of beef-cattle farm management on the reproductive success of Bobolink (Dolichonyx oryzivorus) and Eastern Meadowlark (Sturnella magna) within Eastern Ontario. I monitored rotational grazing management regimes and hay cut dates while assessing breeding phenology and reproductive success of Bobolinks and Eastern Meadowlarks. In pasture paddocks the major factor determining Bobolink reproductive success was the date that cattle entered a paddock to graze, with earlier entries resulting in lower reproductive success. On a landscape scale, within a series of paddocks grazed by a single herd, as the number of paddocks grazed during the nesting season increased, the number of Bobolinks that reproduced successfully decreased. Experimental quantification of trampling showed that cattle exposure to clay pigeon targets, regardless of stocking rates, resulted in the majority of targets being trampled. In hayfields associated with beef- cattle operations, grassland birds had a higher likelihood of success when cutting occurred after 4 July. The best method to improve the reproductive success of Bobolinks and Eastern Meadowlarks is to leave some hayfields and pasture paddocks undisturbed until nesting is complete.

Author Keywords: Bobolink, Dolichonyx oryzivorus, farm management, hayfield, pasture, rotational grazing

2014

Spatial dynamics of pollination in dioecious Shepherdia canadensis in Yukon, Canada

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Creator (cre): Lin, Shang-Yao Peter, Thesis advisor (ths): Dorken, Marcel E, Thesis advisor (ths): Nol, Erica, Degree committee member (dgc): Crins, William J, Degree committee member (dgc): Freeland, Joanna R, Degree granting institution (dgg): Trent University
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Sexual reproduction in flowering plants depends on investment in reproduction, the mode of pollen transfer, the availabilities of nutrient resources and potential mates, and the spatial scales over which these processes take place. In this thesis, I studied the general reproductive biology of Shepherdia canadensis (L.) Nutt. (Elaeagnaceae) and the suite of pollinators that visit the plants in Ivvavik National Park, Yukon, Canada. Across ten sites, I found that S. canadensis females were larger than males, but males produced more flowers than females at most sites. Males typically occurred at higher frequencies than females with the average male to female sex ratio being 1.19 ± 0.08 (mean ± SE, n = 10 sites). Both shrub size and flower production were significantly influenced by interactions between soil nitrogen and sex. Insect visitors to S. canadensis flowers were primarily ants and flower flies (Syrphidae), but exclusion experiments indicated that visitation by flying insects yielded greater fruit production than visitation by crawling insects. I found that fruit set was limited by the density of males within populations, but only over small distances (4-6 m). This is the first study to demonstrate that female reproductive success of a generalist-pollinated dioecious plant is limited by the density of males over small spatial scales.

Author Keywords: dioecy, pollinators, sex ratio, sexual dimorphism, Shepherdia canadensis

2014

Longitudinal trends of benthic invertebrates in regulated rivers: a test of the Serial Discontinuity Concept

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Creator (cre): Lee, Lucy E., Thesis advisor (ths): Jones, Nick E, Degree committee member (dgc): Somers, Keith, Degree committee member (dgc): Beresford, David, Degree granting institution (dgg): Trent University
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The Serial Discontinuity Concept describes the downstream recovery of key biophysical variables below an impoundment. With the proliferation of hydropower dams to meet increasing societal demands, further refinement and understanding of the Serial Discontinuity Concept is needed to accurately predict downstream impacts and ensure the proper management of rivers. In this study, I examine SDC predictions on physical, chemical and biological recovery in regulated rivers providing evidence from 1) a comprehensive literature review and 2) a formal test using two regulated rivers in Northern Ontario. I specifically address how these changes are reflected in benthic invertebrate abundance, diversity, and community composition. The literature review and case studies support the predicted recovery of temperature, periphyton, substrate, and drift. In addition, the study suggests that two recovery gradients exist in regulated rivers: 1) a longer, thermal gradient taking up to hundreds of kilometres downstream; and 2) a shorter, resource subsidy gradient recovering within 1-4 km downstream of an impoundment. Total benthic invertebrate abundance varies considerably and depends on the degree of flow alteration and resource subsidies from the upstream reservoir. In contrast, benthic diversity is reduced below dams irrespective of dam location and operation with little recovery observed downstream. Contrary to SDC predictions, the longitudinal gradient in regulated rivers is not a compaction of functional changes seen over several stream orders in natural rivers but a response to dam design and reservoir conditions. Stoneflies and dragonflies are particularly sensitive to regulation while filter feeding invertebrates are enhanced. Ward and Stanford's (1983) Serial Discontinuity Concept is still a useful framework for testing hypotheses. Future studies should further expand the SDC through empirical estimation within the context of the landscape to gain a better scientific understanding of regulated river ecology.

Author Keywords: benthic invertebrates, dams, longitudinal, recovery, River Continuum Concept, Serial Discontinuity Concept

2013

Dimensions of socio-cultural sustainability: perspectives of Hopedale, Nunatsiavut (Labrador)

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Creator (cre): Kivett Knight, Janet, Thesis advisor (ths): Furgal, Chris, Degree committee member (dgc): Longboat, Dan, Degree granting institution (dgg): Trent University
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Social and cultural sustainability is increasingly discussed in a variety of disciplines and in the growing body of sustainability literature. However there is a lack of clarity in how the concept is defined and poor understanding as to how it relates to other aspects of sustainability. To address this issue, this research explored current definitions and representations of socio-cultural sustainability in the literature and community perspectives on this topic through a case study in Hopedale, Nunatsiavut, Labrador.

This research identifies gaps in current understandings of this concept, as well as differences between community and academic perspectives. Case study results emphasized the importance of strong social relationships, cultural identity, and connection to place as central elements of socio-cultural sustainability in a northern, Indigenous context. These findings are valuable for policy and decision makers, regarding approaches to community planning and supporting the social and cultural aspects of sustainability.

Author Keywords: cultural sustainability, Hopedale, Inuit, Nunatsiavut, social sustainability, socio-cultural sustainability

2014

American Acropolis, American Ruins: Camilo José Vergara's Repeat Photography as Imagistic History

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Creator (cre): Grummitt, Julia, Thesis advisor (ths): Dunaway, Finis, Degree committee member (dgc): Junyk, Ihor, Degree committee member (dgc): Walden, Keith, Degree committee member (dgc): Braddock, Alan C., Degree granting institution (dgg): Trent University
Abstract:

Since 1979, photographer and sociologist Camilo José Vergara has taken repeat photographs of American cities in decline, focusing on evolving landscapes of postindustrial decay. Vergara's images subscribe to an aesthetic of ruin while providing a record of America's crumbling ghettos rooted in social documentary concerns. Vergara's work diverges from the ahistorical tendencies of contemporary ruin porn photography: by challenging the photograph's temporal stasis Vergara bears witness to the ongoing reality of disenfranchisement, assembling an archive that takes up the Benjaminian task of doing history in images. Vergara's photographs challenge standard photojournalistic portrayals of violence, particularly the ways in which `violent' African American and Hispanic inner city populations have been erroneously cast as the cause of their own economic misfortune. The Invincible Cities website assists Vergara in drawing attention to forgotten places but also complicates his mandate to engage outside viewers by distancing them from the real-­world environments his photographs portray.

Author Keywords: Camilo José Vergara, imagistic history, postindustrial decline, repeat photography, ruin porn, Walter Benjamin

2014