Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Resources and risk are in constant flux and an organism's ability to manage change may improve their likelihood of persistence. I examined intra-seasonal variation in nest-site selection and survival of a declining wetland bird, the Black Tern (Chlidonias niger surinamensis). I modelled nest site occupancy and survival of early and late-nesting birds as a function of static and… more Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>North American freshwater fishes are declining rapidly due to habitat fragmentation, degradation, and loss. In some cases, translocations can be used to reverse local extirpations by releasing species in suitable habitats that are no longer naturally accessible. Lake sturgeon (Acipenser fulvescens) experienced historical overharvest across their distribution, leading to endangered… more Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The network composition hypothesis (NCH) suggests that i) large confluence symmetry ratios (drainage area of the tributary relative to the mainstem) and ii) landscape differences (differences in landscape characteristics between the mainstem and tributary drainages) lead to greater ecological changes below confluences. As a test of the NCH, 34 confluences were sampled in southern Ontario… more Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Preston, Colette Alexia, Thesis advisor (ths): McKenna Neuman, Cheryl, Degree committee member (dgc): Boulton, Wayne, Degree committee member (dgc): Buttle, James, Degree committee member (dgc): Eimers, Catherine, Degree granting institution (dgg): Trent University Abstract: <p>A series of experiments was designed to assess the relative efficacy of various dust suppressants to suppress PM10 emissions from nepheline syenite tailings. The experiments were conducted in the Trent University Environmental Wind Tunnel, Peterborough, Ontario, and on the tailings ponds at the Unimin Ltd Nephton mine near Havelock, Ontario. Treated surfaces were subjected to particle-… more Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>To better understand species' resilience to climate change and implement solutions, we must conserve environments that maintain standing adaptive genetic variation and the potential generation of new beneficial alleles. Coding trinucleotide repeats (cTNRs) providing high-pace adaptive capabilities via high rates of mutation are ideal targets for mitigating the decline of species at… more Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study seeks to clarify the way in which the differing canopy characteristics among tree species influence the partitioning of precipitation, and therefore the source of water available for plant water uptake, in the Plastic Lake catchment near Dorset, ON. Three dominant tree species were compared: red oak (Quercus rubra), eastern white pine (Pinus strobus), and eastern hemlock (… more Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>According to the Invasional Meltdown Hypothesis (IMH), invasive species may interact in their introduced range and facilitate future invasions. This study investigated the possibility that Alliaria petiolata, an invasive allelopathic herbaceous plant in Ontario, is facilitating invasions by additional alien species. Two allelopathic focal species were chosen for this study: the native… more Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Wehtje, Morgan, Thesis advisor (ths): Bowman, Jeff, Thesis advisor (ths): Murray, Dennis, Degree committee member (dgc): Fortin, Marie Josee, Degree committee member (dgc): Wilson, Paul, Degree granting institution (dgg): Trent University Abstract: <p>Range contractions and expansions are important ecological concepts for species management decisions. These decisions relate not only to rare and endangered species but to common and invasive species as well. The development of the broad spatiotemporal extent models that are helpful in examining range fluctuations can be challenging given the lack of data expansive enough to cover the… more Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Increases in flooding due to anthropogenic influences such as climate change and reservoir creation will undoubtedly impact aquatic ecosystems, affecting physical, chemical, and biological processes. We used two approaches to study these impacts: a whole-ecosystem reservoir flooding experiment and a systematic literature review. In the whole-ecosystem experiment, we analyzed the impact… more Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Leaf litter decomposition represents a major pathway for nutrient cycling and carbon flow in aquatic ecosystems, and macroinvertebrates play an important role in the processing of this material. To assess the causes of variable leaf breakdown and nutrient fluxes, I measured decomposition rates and the nutrient release ratios of decomposing leaf material across a broad latitudinal… more Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Cytokinins (CKs) are hormones that promote cell division. During the formation of tumors in the Ustilago maydis-Zea mays pathosystem, the levels of CKs are elevated. Although CK levels are increased, the origins of these CKs have not been determined and it is unclear as to whether they promote the formation of tumors. To determine this, we measured the CK levels, identified CK… more Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Effective population size (Ne) is a foundational concept in conservation biology, in part due to its relationship to the adaptive potential of populations. Although Ne is often estimated for wild populations, it is rarely calibrated against actual population estimates (Nc) other than to produce Ne/Nc ratios. This project used demographic and genetic data for from two intensively-studied… more Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>While both resource quality and predator-derived chemical cues can each have profound effects on zooplankton populations and their function in ecosystems, the strength and nature of their interactive effects remain unclear. We conducted laboratory experiments to evaluate how stoichiometric food quality (i.e., algal carbon (C):phosphorus (P) ratios) affects responses of the water flea,… more Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Stream solutes are strongly linked to hydrology, and as such, we sought to better understand how hydrology, particularly flooding, influences nitrogen (N) and phosphorus (P) levels. We used a long-term dataset of monthly water quality samples for many Ontario, Canada, catchments to assess the effects of landscape variables, such as land use and physiography, on the export of nutrients… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Stopover ecology is a topic that surges in relevancy as choices made by migrants during stationary periods (stopover sites) may not only have important individuals' fitness consequences but also can affect population dynamics. I used MOTUS automated telemetry array to study fall stopover duration of Blackpoll Warbler (BLPW) and departure decisions of BLPW and Canada Warbler (CAWA)… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Lock, Alan S., Thesis advisor (ths): Wallschläger, Dirk, Thesis advisor (ths): Belzile, Nelson, Degree committee member (dgc): Belzile, Nelson, Degree committee member (dgc): Gueguen, Celine, Degree granting institution (dgg): Trent University Abstract: <p>A bedrock fracture hosting arsenic (As) contaminated groundwater was suspected to be transported to Ramsey Lake, a drinking water resource for more than 50,000 residents of Sudbury, Ontario. A high resolution, spatial, water quality mapping technique using an underwater towed vehicle (UTV) was used to identify sources of upwelling groundwater into lake water and localize the upwelling As… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The predator vs. prey dynamic is an omnipresent factor in ecological systems that may drive changes in life history patterns in prey animals through behavioural, morphological, and physiological changes. Predation risk can have profound effects on the life history events of an animal, and is influenced by the neuroendocrine stress response. Activation of the hypothalamic-pituitary-… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>A catchment-based study was carried out at three remote acid sensitive Irish lakes to determine concentrations of Hg and POPs and to investigate the factors governing the partitioning of these pollutants in various environmental matrices. Both Hg and POPs are an environmental concern due to their ability to travel long distances via atmospheric transport and their tendency to accumulate… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Paleczny, Andrea Rose, Thesis advisor (ths): Emery, Neil, Degree committee member (dgc): Yee, Janet, Degree committee member (dgc): Saville, Barry, Degree committee member (dgc): Olechowski, Henry, Degree granting institution (dgg): Trent University Abstract: <p>Cytokinins (CKs) are a family of plant phytohormones responsible for many areas of plant growth and development. There are four free base types of CKs found in higher plants, trans-zeatin (tZ), N6-(∆2-isopentenyl)adenine (iP), cis-Zeatin (cZ) and dihydrozeatin (DZ). CK biosynthesis is regulated by adenosine phosphate-isopentenyltransferase (IPT), which is encoded by a multi-gene family… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study was designed to determine the geochemistry and potential toxicity of water draining a large slag pile in Sudbury, Ontario, which runs through a pond complex prior to entering Alice Lake. Slag leaching experiments confirmed slag is a source of sulphate, heavy metals (including Fe, Al, Ni, Co, Cu, Zn, Pb, Cr, Mn) and base cations (Ca, K, Mg, Na). Concentrations of most metals… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Population cycles are regular fluctuations in population densities, however, in recent years many cycles have begun to disappear. With Canada lynx this dampening has also been seen with decreasing latitude corresponding to an increase in prey diversity. My study investigates the role of alternate prey on the stability of the lynx-hare cycle by first comparing the functional responses of… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Arctic Char (Salvelinus alpinus (L.)) have been, and remain, an important</p><p>subsistence resource for the Inuvialuit, the Inuit of the western Canadian Arctic. The effects</p><p>of climate variability and change (CVC) in this region have been noticeably increasing over</p><p>the past three decades. There are concerns as to how CVC will affect Arctic… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The potential release of nanoparticles into aquatic environments is raising global concerns. As antimicrobials, silver nanoparticles (AgNPs) are among the most prominent form in use. Despite this, their fate, long-term toxicity, and ecological relevance have yet to be investigated largely under natural settings with seasonality and environmental complexity. To better understand the… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The purpose of this thesis is to enhance forensic entomology applications through identifications and ecological research with samples collected in collaboration with the OPP and RCMP across Canada. For this, we focus on blow flies (Diptera: Calliphoridae) and present data collected from 2011-2013 from different terrestrial habitats to analyze morphology and species composition.… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Polar bears are generally described as solitary, but features of their life cycles and </p><p>habitats regularly necessitate interaction. Effective conspecific assessment, including accurate </p><p>recognition and discrimination, likely confers benefits, especially to females accompanied by </p><p>dependent young. Individuals in the Southern (SH) and… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Early developmental stages of cold-adapted ectotherms such as brook trout </p><p>(Salvelinus fontinalis) are at risk of mortality with increasing water temperatures because </p><p>of their sensitivity to changes in their environment. I studied the mass and routine </p><p>metabolic rate (RMR) of wild-origin brook trout eggs, alevin and young fry reared… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Biological differences between island and mainland conspecifics have been well studied, but few studies have addressed differences in stress physiology. Stressors, such as predation and competition for resources, cause the release of glucocorticoids (GCs). Characteristics of island wildlife, called "island syndrome", are attributed to low levels of predators and competitors. I… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Wild lupine (Lupinus perennis) restoration efforts seek to increase and connect populations, using seeds, to facilitate the recovery of endangered butterflys in Ontario. This study observed plant growth and phytohormone levels of L. albus, L. polyphyllus, and L. perennis through stages of seed development, each with varying strategies in growth and reproductive investment. L. polyphyllus… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Desantis, Lanna Marie, Thesis advisor (ths): Bowman, Jeff, Thesis advisor (ths): Burness, Gary, Degree committee member (dgc): Rafferty, Steven, Degree committee member (dgc): Wilson, Paul, Degree committee member (dgc): Boonstra, Rudy, Degree committee member (dgc): Vijayan, Mathilakath M, Degree granting institution (dgg): Trent University Abstract: <p>Across vertebrate taxa, the hypothalamic-pituitary-adrenal axis (or the stress axis) is highly conserved, and is central to vertebrate survival because it allows appropriate responses to psychological stressors. Habitat shapes successful physiological and ecological strategies, and to appreciate how individual species respond to stressors in their environment, it is essential to have a… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Franckowiak, Ryan Patrick, Thesis advisor (ths): Wilson, Chris C., Thesis advisor (ths): Ridgway, Mark S., Degree committee member (dgc): Dunlop, Erin S., Degree committee member (dgc): Schaefer, James A., Degree granting institution (dgg): Trent University Abstract: <p>Identifying the biotic and abiotic factors that influence individual reproductive fitness under natural conditions is essential for understanding important aspects of a species' evolutionary biology and ecology, population dynamics, and life-history evolution. Using next generation sequencing technology, I developed five microsatellite multiplex reactions suitable for conducting… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Exposure of pre-metamorphic amphibians to neonicotinoid insecticides may be contributing to the global decline in amphibian populations. In this study, anuran embryos and tadpoles of the African clawed frog (Xenopus laevis) and the North American leopard frog (Lithobates pipiens) were used to determine the effects of embryonic exposure to neonicotinoids. In addition, Xenopus was used to… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Mountain ranges are often thought to restrict movement of wildlife, yet previous studies evaluating the role of the Rocky Mountains as a dispersal barrier for Canada lynx (Lynx canadensis) have been contradictory. Our study uses neutral microsatellite loci to evaluate the role of the Rocky Mountains as a barrier to gene flow for lynx. Although lynx exhibited low genetic differentiation,… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Blackfin Cisco (Coregonus nigripinnis), a deepwater cisco species once endemic to the Laurentian Great Lakes, was discovered in Algonquin Provincial Park in four lakes situated within a drainage outflow of glacial Lake Algonquin. Blackfin habitat preference was examined by analyzing which covariates best described their depth distribution using hurdle models in a multi-model approach.… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>I examined Bank Swallow (Riparia riparia) colony persistence and occupancy, in lakeshore, river and man-made aggregate pit habitat. Habitat persistence was highest on the lakeshore and lowest in aggregate pits, likely due to annual removal and relocation of aggregate resources. Bank Swallow colonies in aggregate pit sites were more likely to persist if a colony was larger or if burrows… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Socio-ecological systems are inherently complex and marine mammals are fundamentally challenging to study. In the Arctic, marine mammals occupy a central ecological role, as nutrient cyclers and as a source of food and culture for Indigenous peoples. Inuit have developed a rich knowledge system, which has not been fully actualized in application in most Arctic research. Considering the… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Metal binding to dissolved organic matter (DOM) determines metal speciation and strongly influences potential toxicity. The understanding of this process, however, is challenged by DOM source variation, which is not always considered by most existing metal speciation models. Source determines the molecular structure of DOM, including metal binding functional groups. This study has… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The amitochondrial protozoan, Giardia intestinalis, encodes four members of the cytochrome b5 (CYTB5) family of heme proteins of unknown function. While homology models can predict the likely fold of these proteins, supporting experimental evidence is lacking. The small size of the cytochromes (~16 kDa) makes them attractive targets for structural analysis by Electron Paramagnetic… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The parasitic protist Giardia intestinalis lacks most heme proteins yet encodes a flavohemoglobin (gFlHb) that converts nitric oxide to nitrate and likely protects the cell from nitrosative stress. In this work an antibody raised against gFlHb was used to examine both changes in gFlHb expression levels and intracellular localization in Giardia in response to nitrosative stress. Giardia… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study focused on detecting 22 target anti-estrogenic and anti-androgenic compounds in surface waters influenced by both discharges of municipal wastewater and agricultural runoff in Canada and Argentina. Polar organic chemical integrative samplers (POCIS) were used to monitor the target compounds in surface waters. The removals of the target compounds in a municipal wastewater… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>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 (… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Timber harvest can influence the rate of transfer of organic matter from the terrestrial catchment to streams, which may have both direct and indirect effects on in-stream nutrient pools and dynamics. In the interest of developing sustainable forestry practices, the continued study of the effects of forestry on nutrient dynamics in aquatic systems is paramount, particularly in sensitive… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Ogungbemide, Damilare Immanuel, Thesis advisor (ths): McKenna Neuman, Cheryl, Degree committee member (dgc): Lafleur, Peter, Degree committee member (dgc): Buttle, Jim, Degree committee member (dgc): Hill, Stephen, Degree granting institution (dgg): Trent University Abstract: <p>A set of experiments was designed to investigate the factors—atmospheric and surficial—controlling fugitive dust emissions from the tailings ponds of UNIMIN Canada, a mining company that extracts and produces nepheline syenite (feldspar) at two adjacent sites (Nephton and Blue Mountain) located north of Havelock, Ontario. Using wind tunnel measurements, the combined influence of relative… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Currier, Charise A., Thesis advisor (ths): Freeland, Joanna, Thesis advisor (ths): Wilson, Chris C, Degree committee member (dgc): Morris, Todd J, Degree committee member (dgc): Schaefer, James A, Degree granting institution (dgg): Trent University Abstract: <p>Environmental DNA (eDNA) detection uses species-specific markers to screen DNA from bulk samples, such as water, to infer species presence. This study involved the development and testing of species-specific markers for four freshwater pearly mussels (Unionidae). The markers were applied to water samples from intensively sampled mussel monitoring sites to compare species detections from… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>In this thesis, water mass distribution of dissolved organic matter (DOM) characteristics (i.e. molecular weight, fluorescent components, thiols and humic substances concentration) was observed in the Arctic Ocean. For the first time, DOM molecular weight (MW) in Beaufort Sea was assessed using asymmetrical flow field-flow fractionation, as well as the first monitoring of thiols and… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Puccinia triticina, wheat leaf rust (WLR), is the most economically damaging fungal rust of wheat on a global scale. This study identified transcriptome changes in a recently emerged race of WLR in Ontario with a new virulence type relative to a possible ancestor race. Also, this study focused on detecting variation in candidate virulence genes and uncovering novel insight into WLR… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>To study the Giardia intestinalis cell cycle, counterflow centrifugal elutriation (CCE) was used to separate an asynchronous trophozoite culture into fractions enriched for cells at the different stages of the cell cycle. For my first objective, I characterized the appearance of a third peak (Peak iii) in our flow cytometry analysis of the CCE fractions that initially suggested the… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>In 2008, the first North American water soldier (Stratiotes aloides) population was discovered in the Trent River, Ontario. Water soldier is an invasive aquatic plant with sharp, serrated leaves that has the potential to spread rapidly through dispersed vegetative fragments. Although it is too late to prevent water soldier establishment in the Trent River, its local distribution remains… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The release of domestic organisms to the wild is considered a threat to </p><p>biodiversity because the introduction of domestic genes through interbreeding can </p><p>negatively impact wild conspecifics via outbreeding and local extinction. In North </p><p>America, captive American mink (Neovison vison) are frequently escaping into the wild, </p… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Poole, Sarah Kathleen, Thesis advisor (ths): Obbard, Martyn E., Thesis advisor (ths): Schaefer, James A., Degree committee member (dgc): Nocera, Joseph J., Degree committee member (dgc): Ray, Justina C., Degree granting institution (dgg): Trent University Abstract: <p>I investigated site fidelity and habitat selection of American black bears (Ursus americanus) from 15 GPS-collared adult females in central Ontario, Canada over nine years. I used generalized linear mixed models to determine the factors affecting between-year variation in fall fidelity and the habitat selection in movement paths. I assessed second and third-order habitat preference by… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Stressors are often an inescapable part of an organism's life. While the effects of many stressors have been well studied individually, potential interactions between stressors exist that may result in greater than additive negative effects. Stressors may be linked by conflicting demands on energy budgets, interfering with important physiological pathways, or necessitating… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Tree harvesting alters nutrient cycling and removes nutrients held in biomass, and as a result nutrient availability may be reduced, particularly in naturally oligotrophic ecosystems. Selection harvesting is a silvicultural technique limited to tolerant hardwood forests where individual or small groups of trees are removed creating a "gap" in the forest canopy. In order for… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>As an emerging contaminant, the antimicrobial agent silver nanoparticles (AgNPs) have been receiving considerable attention to determine their potential effects to aquatic ecosystems. However, estimates of aquatic consumer survivorship and other toxicological endpoints vary considerably among experiments, largely due to the environment in which the test takes place. Throughout this… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The Oak Ridges Moraine (ORM) is a key hydrogeologic feature in southern Ontario. Previous work has emphasized the importance of depression-focused recharge (DFR) for the timing and location of groundwater recharge to the ORM's aquifers. However, the significance of DFR has not been empirically demonstrated and the relative control of land cover, topography, and surficial geology on… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Invasive aquatic plants can create negative ecological, economic and social impacts when they displace local vegetation, interfere with shipping and navigation and inhibit water-based recreational activities. In 2008, the first North American occurrence of the invasive plant Stratiotes aloides (Water soldier) was identified in the Trent River, Ontario. This research measured offset… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Masson, Laurence, Thesis advisor (ths): Fox, Michael G, Degree committee member (dgc): Wilson, Chris C, Degree committee member (dgc): Copp, Gordon H, Degree committee member (dgc): Beisel, Jean-Nicolas, Degree granting institution (dgg): Trent University Abstract: <p>Researchers have shown increasing interest in biological invasions for the associated ecological and economic impacts as well as for the opportunities they offer to study the mechanisms that induce range expansion in novel environments. I investigated the strategies exhibited by invasive species that facilitate range expansion. Invasive populations exhibit shifts in life-history strategy… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Dayer, Guillem Sébastien, Thesis advisor (ths): Yee, Janet, Thesis advisor (ths): Rafferty, Steven, Degree committee member (dgc): Brunetti, Craig, Degree committee member (dgc): Saville, Barry, Degree granting institution (dgg): Trent University Abstract: <p>Giardia intestinalis is an anaerobic protozoan that lacks common eukaryotic heme-dependent respiratory complexes and does not encode any proteins involved in heme biosynthesis. Nevertheless, the parasite encodes several hemeproteins, including three members of the Type II cytochrome b5 sub-group of electron transport proteins found in anaerobic protist and amitochondriate organisms.… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Moose are an iconic species, known for their large size and impressive antlers. Eight subspecies are classified in circumpolar regions of the planet - four in North America. Two subspecies are similar in shape and size, the north-western moose (Alces alces andersoni) and the eastern moose (Alces alces americana). It was previously believed that these two subspecies meet in northern… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Long-term studies of demographic processes such as survival and abundance conducted in unexploited systems provide unique insight into the natural population ecology of fish, but are rarely available. I used historical tagging records of a sanctuary population of brook trout (Salvelinus fontinalis) in Algonquin Park, Ontario to investigate long-term population dynamics in an unexploited… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study assesses the bioavailable metal (Cu, Ni, Zn, Pb) species in the Athabasca-Mackenzie watersheds using diffusive gradient in thin films (DGT) devices. Metal toxicity is not only based on the concentration of metal in natural waters, but also on the nature of metal species. Four main forms in aquatic systems are: free ion, inorganic species, DOM bound (humic) species and metal… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The recent northward expansion of the white-footed mouse (Peromyscus leucopus) in response to climatic changes provides a natural experiment to explore potential adaptive genetic variation within the clock gene Per1 in Peromyscus undergoing latitudinal shifts, as well as, the possibility of hybridization and introgression related to novel secondary contact with its sister species the… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Daphnia are keystone consumers in many pelagic ecosystems because of their central role in nutrient cycling. Daphnia are also frequently infected, and the parasites causing these infections may rival their hosts in their ability to regulate ecosystem processes. Therefore, parasitic exploitation of Daphnia may alter nutrient cycling in pelagic systems. This thesis integrates existing… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Improving current understanding of the factors that control soil carbon (C) dynamics in forest ecosystems remains an important topic of research as it plays an integral role in the fertility of forest soils and the global carbon cycle. Invasive earthworms have the potential to alter soil C dynamics, though mechanisms and effects remain poorly understood. To investigate potential effects… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The objective of this thesis was to assess current spatial trends and historic trends in the accumulation of trace metals related to the Athabasca Oil Sands Region (AOSR). The AOSR hosts some of the largest industrial developments in Canada, yet relatively little is known about the transport and fate of trace metal emissions from the region – particularly in the relatively remote areas… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>While previous studies have focused on how road salt affects water quality and vegetation, limited research has characterized road salt distribution through soil and the resulting impacts. The potential for sodium (Na+) to be retained and impact soil physical and chemical properties is likely to vary depending on the soil's parent material, and more specifically on the extent of… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Decomposition of aquatic macrophytes has an important role in defining lake carbon (C) storage and nutrient dynamics. To test how diversity impacts decomposition dynamics and site-quality effects, I first examined whether the decomposition rate of aquatic macrophytes varies with species richness. Generally, I found neutral effects of mixing, with initial stoichiometry of component… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The flavohemoglobin in Giardia intestinalis (gFlHb) is the only known protozoan member of a protein class typically associated with detoxifying nitric oxide (by oxidation to nitrate) in bacteria and yeast. Mutants of the B10 tyrosine (Y30F) and E11 leucine (L58A), conserved residues thought to influence ligand binding, were expressed and studied using Resonance Raman (RR) spectroscopy.… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Environmental variation can affect consumer trait expression and alter ecological and evolutionary dynamics in natural populations. However, although dietary nutrient content can vary by an order of magnitude in natural ecosystems, intra-specific differences in consumer responses to food quality have not been thoroughly investigated. Therefore, the purpose of my dissertation was to… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Arctic terrestrial ecosystems have experienced substantial structural and compositional changes in response to warming climate in recent decades, especially the expansion of shrub species in Arctic tundra. Climatic and vegetation changes could feedback to the global climate by changing the carbon balance of Arctic tundra. The objective of this thesis was to investigate the influence of… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Despite being an essential nutrient at trace levels, selenium can be devastating to aquatic environments when present in excess. There is no apparent correlation between total aqueous selenium concentrations and observed toxic effects because bioaccumulation varies over several orders of magnitude depending on the chemical species of selenium and the biological species present in the… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Micropollutants are discharged into the aquatic environment with industrial and domestic wastewater and these compounds may cause toxic effects in aquatic organisms. In this study, the toxic effects to fish of micropollutants extracted from ozonated and nonozonated municipal wastewater effluent (MWWE) were measured in order to assess the effectiveness of ozonation in reducing toxicity.… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The epoxides of oligomeric self-metathesized soybean oil (MSBO) and cross-metathesized palm oil (PMTAG) and canola oil (CMTAG) containing terminal double bonds were used to produce nonisocyanate polyurethanes (NIPUs) as well as anhydride, amine and thiol-cured epoxies. </p><p>The synthesized NIPUs displayed metal adhesive properties for CMTAG and MSBO with MSBO being favoured… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>A species of concern is caribou (Rangifer tarandus), a species in decline across most of the circumpolar North, including the island of Newfoundland. Resource exploitation across caribou ranges is projected to accelerate in the coming decades as oil extraction, roads, forest harvesting, and mining encroach upon their habitat. Hydroelectric corridors, in particular, are anticipated to… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Giardia intestinalis is a protozoan parasite that causes waterborne diarrheal disease in animals and humans. It is an unusual eukaryote as it lacks the capacity for heme biosynthesis; nonetheless it encodes heme proteins, including three cytochrome b5 isotypes (gCYTB5s) of similar size. Homology modelling of their structures predicts increased heme pocket polarity compared to mammalian… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Interseeding legume cover crops in grain corn may improve the environmental sustainability of corn production system in Southern Ontario. This study aimed to assess the effects of legume species, nitrogen (N) fertilizer rate and arbuscular mycorrhizal fungi (AMF) inoculation on biomass and N requirement in a corn-legume system. Corn was grown with red clover (RCl), microclover (MCl),… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The aim of this work was to identify the DNA sequences recognized by the Giardia TBP (gTBP) in vivo by using a chromatin immunoprecipitation assay (ChIP). Since a specific antibody for the protein of interest is required for this assay, a company was contracted to produce and purify a custom polyclonal antibody from the immunization of rabbits. Recombinant GST-gTBP was produced at a… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Serrao, Natasha Rosemary, Thesis advisor (ths): Wilson, Chris C, Degree committee member (dgc): Dextrase, Alan, Degree committee member (dgc): Freeland, Joanna, Degree committee member (dgc): Reid, Scott, Degree granting institution (dgg): Trent University Abstract: <p>Recent range reductions of endangered species have been linked to urban development, increased agricultural activities, and introduction of non-native species. I used Redside Dace (Clinostomus elongatus) as a focal species to examine the utility of novel monitoring approaches, and to understand historical and contemporary processes that have influenced their present distribution. I… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study assesses the ability of a unicellular protist, Euglena gracilis, to remove Cu and Ni from solution in mono- and bi-metallic systems. Living Euglena cells and non-living Euglena biomass were examined for their capacity to sorb metal ions. Adsorption isotherms were used in batch systems to describe the kinetic and equilibrium characteristics of metal removal. In living systems… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Shetranjiwalla, Shegufta, Thesis advisor (ths): NARINE, SURESH S, Thesis advisor (ths): Vreugdenhil, Andrew, Degree committee member (dgc): Metcalfe, Chris, Degree committee member (dgc): Dawson, Peter, Degree granting institution (dgg): Trent University Abstract: <p>Thermoplastic poly(ester urethane)s (TPEU)s derived from vegetable oils possess inferior physical properties compared to their entirely petroleum-based counterparts due to the structural limitations and lower reactivity of the precursor lipid-derived monomers. The present work shows that high molecular weight of TPEUs with enhanced performance can be obtained from lipid-derived monomers… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study examines the influence of dissolved organic matter (DOM) on dissolved vanadium (V) speciation in the Churchill River and Great Slave Lake using diffusive gradients in thin film (DGT). Vanadium is commonly found in natural environments such as rivers, lakes and oceans. It regulates normal cell growth, but in excessive amounts, it can have toxic effects on human and aquatic… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Based on an endogenous hormone study, three cytokinin type phytohormones; benzyladenine (BA), trans-zeatin (tZ) and methylthiol trans-zeatin (MeSZ), as well as abscisic acid (ABA) were exogenously added at three concentrations (10-7, 10-6 and 10-5 M) to cultures of Chlorella vulgaris in an attempt to alter growth rate, total lipid and fatty acid yields and fatty acid profile. Growth… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The cyanidation technique is currently a viable technique for gold recovery that can replace the present amalgamation technique in Guyana. To implement this technique effectively, laboratory scale experiments and at scale runs were conducted to determine the best particle size of the ore, cyanide concentration, and leaching time. In addition, the profitability of cyanidation was compared… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Northern and southern flying squirrels (Glaucomys sabrinus and G. volans, respectively) are experiencing a climate change induced increase in range overlap, resulting in recent hybridization. We investigated the occurrence of heterospecific communal nesting, a potential facilitator of hybridization, and aimed to confirm the presence of torpor, a potential barrier to hybridization, in… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Phosphorus (P) is an essential macronutrient. In south-central Ontario, foliar P concentrations are low and studies have suggested that P may be limiting forest productivity. Current catchment mass balance estimates however, indicate that P is being retained suggesting that P should not be limiting to tree growth. Phosphorus deposition is measured using bulk deposition collectors, which… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This thesis explored the contribution of mixed methods approaches to marine mammal science through the use of concurrent and sequential designs to study distribution and feeding ecology of bowhead whales (Balaena mysticetus) in the Arctic region of Nunavik, Quebec, Canada. The study combines Inuit knowledge (IK), collected through semi-directed interviews with Inuit harvesters, and… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Otis, Josée-Anne, Thesis advisor (ths): Murray, Dennis, Degree committee member (dgc): Thornton, Daniel, Degree committee member (dgc): Bowman, Jeff, Degree committee member (dgc): Conolly, James, Degree granting institution (dgg): Trent University Abstract: <p>Currently there are large areas of the North American landscape that are occupied by Canis spp. hybrids of several varieties, leading to the logical question as to the genetic structure and ecological function of Canis populations across the continent, and to what extent hybrids reflect contemporary landscapes. This study illustrated patterns of niche differentiation between parental… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Cytokinin biosynthesis in organisms aside from plant species has often been viewed as a byproduct of tRNA degradation. Recent evidence suggests that these tRNA degradation products may actually have a role in the development of these organisms, particularly fungi. This thesis examines the importance of cytokinins, a group of phytohormones involved in plant cell division and… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Fishers (Pekania pennanti) were extirpated from many parts of Ontario in the early 20th century, but as of the early 2000s the species had recolonized most of its historical range. While the primary population genetic structure of fishers in central and eastern Ontario has not changed drastically over the past ten years, we did find evidence of increased secondary structure and a… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The activities of phytohormones during the reproductive phase have been partially clarified in seed physiology while the biological role of plant hormones in oil accumulation during seed development has been investigated in part only. In this research, fatty acid (FA) contents and hormone profiles, including abscisic acid (ABA) and cytokinins (CKs) of seed samples in four different… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>There are three cattail (Typha) taxa in Canada: T. latifolia (native), T. angustifolia (introduced), and their hybrid T. x glauca. The latter is invasive in regions around the Laurentian Great Lakes, and I investigated the potential role that commercial suppliers may be playing in the introduction of non-native Typha by comparing genotypes of North American, European, and commercially… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Total phosphorus (TP) concentrations have declined in many lakes and streams across south- central Ontario, Canada over the past three decades and changes have been most pronounced in wetland-dominated catchments. In this study, long-term (1980-2007) patterns in TP concentrations in streams were assessed at four wetland-dominated catchments that drain into Dickie Lake (DE) in south-… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Migratory and sedentary ecotypes are phenotypic distinctions of woodland caribou. I explored whether I could distinguish between these ecotypes in Manitoba and Ontario using genetic signatures of adaptive differentiation. I anticipated that signatures of selection would indicate genetic structure and permit ecotype assignment of individuals. Cytochrome-b, a functional portion of the… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The emission of acid precursors by large point sources in Western Canada</p><p>(such as the Athabasca Oil Sands Region) has prompted studies into the possible impact to downwind aquatic and terrestrial ecosystems. Sensitivity of catchments to acidic deposition was estimated for the total lake population of northern Saskatchewan (n=89,947) using regression kriging. Under the… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Most delphinids produce narrowband frequency-modulated whistles with a high level of plasticity to communicate with conspecifics. It is important to understand geographic variation in whistles as signal variation in other taxa has provided insight into the dispersal capabilities, genetic divergence and isolation among groups, and adaptation to ecological conditions. I investigated… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Sex-specific genetic structure is a commonly observed pattern among vertebrate species. Facing differential selective pressures, individuals may adopt sex-specific life historical traits that ultimately shape genetic variation among populations. Although differential dispersal dynamics are commonly detected in the literature, few studies have investigated the potential effect of sex-… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Cuss, Chad Warren, Thesis advisor (ths): Gueguen, Celine, Degree committee member (dgc): Watmough, Shaun, Degree committee member (dgc): McConnell, Sabine, Degree committee member (dgc): Dillon, Peter, Degree granting institution (dgg): Trent University Abstract: <p>Dissolved organic matter (DOM) is a mixture of molecules with dynamic structure and composition that are ubiquitous in aquatic systems. DOM has several important functions in both natural and engineered systems, such as supporting microorganisms, governing the toxicity of metals and other pollutants, and controlling the fate of dissolved carbon. The structure and composition of DOM… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Urban and agricultural activities may introduce chemical stressors, including contaminants of emerging concern (CECs) and current use pesticides (CUPs) into riverine systems. The objective of this study was to determine if fish collected from sites in a river show biomarkers of exposure to these classes of contaminants, and if the biomarker patterns vary in fish collected from urbanized… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Aquatic consumers frequently face nutritional limitation, caused in part, by imbalances between the nutrients supplied by primary producers and the metabolic demands of the consumers. These nutritional imbalances alter many ecological processes including consumer life-history traits, population dynamics, and food web properties. Given the important ecological role of organismal nutrition… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>As part of a mandate to control the spread of Stratiotes aloides (WS; water soldier) in the Trent Severn Waterway, the Ministry of Natural Resources (MNR) created a management plan to eradicate WS. However, one of the biggest challenges in eradicating WS or any invasive aquatic plant is the ability to estimate the extent of its spread and detect new populations. While current detection… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Klein, Michelle Nicole, Thesis advisor (ths): White, Brad N., Thesis advisor (ths): Wang, John Y., Degree committee member (dgc): Nocera, Joseph J., Degree committee member (dgc): Kerr, Leslie R., Degree granting institution (dgg): Trent University Abstract: <p>Marine mammals with near-shore distributions are susceptible to human-related recreational and commercial disturbances, particularly near densely populated and industrialized coastal areas. A population of over 2,500 Chinese humpback dolphins (Sousa chinensis chinensis) occupies the Pearl River Estuary in southern China. A part of this population uses Hong Kong's waters off of… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Ustilago maydis is a basidiomycete smut fungus and the causal agent of common smut of corn. Disease progression and fungal development in this pathogen occur in planta, terminating in the production of dormant teliospores. Dormant spores of many fungi are characterized by reduced metabolic activity, which is restored during spore germination. The transition out of dormancy requires the… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Agricultural land application of biosolids recycles nutrients and organic matter to the soil, however the effect of treatment process on nutrient availability requires further research for better nutrient management. This study examined the bioavailability of nitrogen (N) and phosphorus (P) in alkaline treated biosolids (TB) when amended into three different soils. Despite a 45%… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Trinucleotide repeats (TNRs) are a class of highly polymorphic microsatellites which occur in neutral and non-neutral loci and may provide utility for individual- and population-identification. Exonic trinucleotide motifs, in particular, offer additional advantages for non-human species that typically utilize dinucleotide microsatellite loci. Specifically, the reduction of technical… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Road mortality is one of the leading causes of global population declines in reptiles and amphibians. Stemming losses from reptile and amphibian road mortality is a conservation priority and mitigation is a key recovery measure. I developed a model of road mortalities relative to non-‐mortalities, based on predictors varying across space (road surface type, traffic volume, speed limit,… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>In this thesis, a methodological framework for the assessment and monitoring of forest degradation based on remote sensing techniques and field data, as part of the REDD+ programme, is presented. The framework intends to support the implementation of a national Monitoring, Verification and Report (MRV) system in developing countries. The framework proposed an operational definition of… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Soil mineralizable nitrogen (N) is the main component of soil N supply in humid temperate regions and should be considered in N fertilizer recommendations. The objectives of this study were to determine the potentially mineralizable N parameters, and improve N fertilizer recommendations by evaluating a suite of soil N tests in southwestern Ontario. The study was conducted over the 2013… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>(MRC) in central Ontario was carried out to determine the range and spatial distribution of soil Ca weathering rates, and investigate the relationships between lake Ca and soil and catchment attributes. The MRC is acid-sensitive, and has a long history of impacts from industrial emission sources in Ontario and the United States. Small headwater catchments were sampled for soil and… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>In this study, the influence of N deposition on the vegetation community of semi-natural oak woodlands in Ireland was assessed through national and regional scale analysis of forest plot data. At both scales, Canonical Correspondence Analysis suggested that N deposition was a predictor of community composition, although site-specific soil characteristics were the strongest predictors of… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Celsie, Alena Kathryn Davidson, Thesis advisor (ths): Mackay, Donald, Thesis advisor (ths): Parnis, Mark, Degree committee member (dgc): Hickie, Brendan, Degree committee member (dgc): Mackay, Donald, Degree committee member (dgc): Parnis, Mark, Degree committee member (dgc): Aherne, Julian, Degree granting institution (dgg): Trent University Abstract: <p>Models of partitioning, uptake, and toxicity of neutral organic chemicals in fish</p><p>Alena Kathryn Davidson Celsie</p><p>A novel dynamic fugacity model is developed that simulates the uptake of chemicals in fish by respiration as applies in aquatic toxicity tests. A physiologically based toxicokinetic model was developed which calculates the time-course of… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study investigated the role of the JNK signaling pathway in cadmium-treated mouse embryo forelimb bud cells in vitro. Primary cultures of forelimb bud cells harvested at day 11 of gestation were pre-treated with JNK inhibitor SP600125, and incubated with or without CdCl2 for 15, 30, 60, 120 minutes and 24, 48 hours or 5 days. Endpoints of toxicity were measured through cell… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The purpose of this study was to quantify the variation of baseline carbon and nitrogen stable isotope signatures in the Lake Simcoe watershed and relate that variation to various physicochemical parameters. Particulate organic matter samples from 2009 and 2011 were used as representatives of baseline isotopic values. Temporal data from two offshore lake stations revealed that δ… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The objective of this thesis is to better understand the demography and habitat selection of Newfoundland caribou. Chapter 1 provides a general introduction of elements of population ecology and behavioural ecology discussed in the thesis. In Chapter 2, I examine the causes of long-term fluctuations among caribou herds. My findings indicate that winter severity and density-dependent… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Baya, Pascale Anabelle, Thesis advisor (ths): Hintelmann, Holger, Degree committee member (dgc): Lamborg, Carl, Degree committee member (dgc): Hickie, Brendan, Degree committee member (dgc): Georg, Bastian, Degree granting institution (dgg): Trent University Abstract: <p>Monomethylmercury (MMHg), the most bioavailable form of mercury (Hg) and a potent neurotoxin, is present at elevated concentrations in Arctic marine mammals posing serious health threats to the local populations relying on marine food for their subsistence living. The sources of MMHg in the Arctic Ocean surface water and the role of dimethylmercury (DMHg) as a source of MMHg remain… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Population density regulation is a fundamental principle in ecology, however there remain several unknowns regarding the functional expression of density dependence. One prominent view is that the patterns by which density dependence is expressed are largely fixed across a species, irrespective of environmental conditions. Our study investigated the expression of density dependence in… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Extensive research has gone into measuring changes to the carbon storage capacity of Arctic terrestrial environments as well as large water bodies in order to determine a carbon budget for many regions across the Arctic. Inland Arctic waters such as small lakes and ponds are often excluded from these carbon budgets, however a handful of studies have demonstrated that they can often be… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Browning, Mark Henry, Thesis advisor (ths): Davies, Chris, Thesis advisor (ths): Buttle, Jim, Degree committee member (dgc): Lafleur, Peter, Degree committee member (dgc): Whillans, Tom, Degree granting institution (dgg): Trent University Abstract: <p>Theoretical work on community recovery, development, stability, and resistance to species invasions has outpaced experimental field research. There is also a need for better integration between ecological theory and the practice of ecological restoration. This thesis investigates the dynamics of community assembly following peat mining and subsequent restoration efforts at Canada's… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Climate change has had numerous impacts on species' distributions by shifting suitable habitat to higher latitudes and elevations. These shifts pose new challenges to biodiversity management, in particular translocations, where suitable habitat is considered crucial for the reintroduced population. De-extinction is a new conservation tool, similar to reintroduction, except that the… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Sherritt, Ayden Frazer, Thesis advisor (ths): Schaefer, James A, Thesis advisor (ths): Pond, Bruce A, Degree committee member (dgc): Brown, Glen S, Degree committee member (dgc): Brannen, Dennis, Degree granting institution (dgg): Trent University Abstract: <p>Site fidelity is the behaviour of individuals to return to the same location; for female woodland caribou it may reflect reproductive success and depend on habitat quality. I investigated the influence of landscape and disturbance conditions on fidelity among three populations in Manitoba and Ontario, Canada. Habitat classifications were based on Forest Resource Inventory (FRI) and… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Pacific Rim National Park Reserve's 16 km of coastal beaches attract many thousands of people and shorebirds every year. To identify locations where shorebirds concentrate and determine the impact of human activity and habitat characteristics on shorebirds, I conducted shorebird and visitor surveys at 20 beach sectors during fall migration in 2011 to 2013 and spring migration in… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Zigouris, Joanna, Thesis advisor (ths): Schaefer, James A, Thesis advisor (ths): Kyle, Christopher J, Degree committee member (dgc): Wilson, Paul J, Degree committee member (dgc): Bowman, Jeff, Degree granting institution (dgg): Trent University Abstract: <p>Habitat loss and fragmentation can disrupt population connectivity, resulting in small, isolated populations and low genetic variability. Understanding connectivity patterns in space and time is critical in conservation and management planning, especially for wide-ranging species in northern latitudes where habitats are becoming increasingly fragmented. Wolverines (Gulo gulo) share… more Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Livestock predation by wild predators is a frequent and complicated issue, often cited as a significant factor in the decline of livestock production and justification for killing predators. Coyotes (Canis latrans) are the primary predators of sheep in Ontario. Some farms appear to be more susceptible to predation than others, despite the use of mitigation techniques. I explored land… more
