Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The purpose of this thesis is to quantify the habitat characteristics, density patterns and environmental niches of two groups of Indo-Pacific humpback dolphins: Chinese white dolphins (CWD) of the Pearl River estuary (PRE), and Taiwanese white dolphins (TWD, =Taiwanese humpback dolphin, THD) found in the eastern Taiwan Strait (ETS). Much work has already been done on the habitat use of… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Since its introduction to North America in the 1990s, the Round Goby has spread throughout the Great Lakes, inland through rivers and is now moving into small tributary streams, a new environment for this species in both its native and invaded ranges. I explored density and temporal occupation of Round Gobies in four small streams in two systems in south-central Ontario, Canada in order… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Bees (clade Anthophila), are poorly studied in northern Canada, as these regions can be difficult to access and have a short growing season. This study examined bees from two such regions: Ontario's Far North, and Akimiski Island, Nunavut. I present this study as the largest biogeographical study of bees performed in these remote areas to enhance knowledge of northern native bees. I… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>In this thesis, aerosolization was studied as a possible means of water remediation for several environmentally relevant pharmaceutical pollutants, known for their persistence in wastewater effluent and potable water sources. Seven different pharmaceutical compounds and a well-known plasticizer were all shown to decrease considerably in concentration in aerosol that was produced and… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The spatial and temporal variation in atmospheric nitrogen dioxide (NO2), ammonia (NH3), and 17 elements (V, Cr, Fe, Ni, Cu, Zn, As, Cd, Pb, Mg, Al, Ca, Co, Se, Sb, Mn, and Na) were measured at 40 road side locations along a ~250 km traffic density gradient of 40,000–400,000 vehicles on the King's Highway 401, in Ontario, Canada. Elemental concentrations were measured over a year,… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Dissolved organic matter (DOM) in oceans provides nutrients and ultraviolet radiation protection to microbes. Some DOM compounds can chelate with metals, including copper, controlling their transport and bioavailability in marine systems. As copper functions as both a nutrient and toxicant, studies into the chemical structures of Cu-ligands is important, however currently limited. In… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Natural establishment of vegetation on mine tailings is generally limited. Understanding the processes leading to vegetation germination and the survival mechanisms that vegetation species employ in these harsh environments is critical to future remediation efforts. As metalliferous mine tailings are generally nutrient-poor, high in harmful metals, and acidic, vegetation species require… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The parasitic protist Giardia intestinalis possesses flavohemoglobin (gFlHb), an enzyme that detoxifies nitric oxide to the less harmful nitrate, and is a potential target for antigiardial drugs that act as ligands to the iron of its heme cofactor. In this work, the binding constants KD of gFlHb, three active-site variants (Q54L, L58A, Y30F) and the E. coli flavohemoglobin (Hmp) towards… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>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… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Many rare and elusive species have low detection probabilities, thereby imposing unique challenges to monitoring and conservation. Here, we assess the detection probability of the Eastern Massasauga (Sistrurus catenatus) in contrast to a more common and conspicuous species, the Eastern Gartersnake (Thamnophis sirtalis). We found that patterns of detection probability differed between… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Recent declines in North American shorebird populations could be linked to habitat loss on the non-breeding grounds. Sea-level rise and increased frequency of coastal storms are causing significant erosion of barrier islands, thereby threatening shorebirds who rely on shoreline habitats for foraging. I conducted shorebird surveys on Bulls Island, South Carolina in the winters of 2018 and… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The parasitic protist Giardia intestinalis does not synthesize heme and lacks many common eukaryotic heme proteins, yet it expresses four cytochrome b5 (gCYTB5) isotypes of unknown function. These have low reduction potentials and distinct subcellular locations that are consistent with structural features and biological functions that differ from their mammalian counterparts. Isotype III… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Aquatic contaminant mobility and biological availability is strongly governed by the complexation of organic and inorganic ligands. Dissolved organic matter (DOM) is a complex, heterogeneous mixture of organic acids, amino acids, lipids, carbohydrates and polyphenols that vary in composition and can complex to dissolved metals thereby altering their fate in aquatic systems. The research… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Contemporary evolution has the potential to help limit the biological impact of rapidly changing climates, however it remains unclear whether wild populations can respond quickly enough for such adaptations to be effective. In this thesis, I used the introduction of native North American Pumpkinseed (Lepomis gibbosus) into the milder climate of Europe over 140 years ago, as a '… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Environmental monitoring and investigation of metal biogeochemical cycling has been</p><p>carried out in the Pearl River Estuary (PRE), an important and complex system in Southern</p><p>China. In this study, rare earth element (REE) patterns as well as isotope ratios (i.e., Zn and Cd)</p><p>were evaluated as tools to identify contamination sources in… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Range expansion by the bobcat (Lynx rufus) may be contributing to range contraction by the Canada lynx (Lynx canadensis), but interactions between them are not well understood. To investigate the potential for competition, I conducted a literature review of hierarchical habitat selection by these two species. I determined that the lynx and the bobcat select different resources at the… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Wild populations are notoriously difficult to study due to confounding stochastic variables. This thesis tackles two components of investigating wild populations. The first examines the use of niche modeling to quantify macro-scale predator-prey relationships in canid populations across eastern North America, while the second examines range-wide molecular structure in Canada lynx. The… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Mixtures of metals occur in surface waters, toxicity of which has drawn world-wide attention due to their crucial role in both ecotoxicology and regulations. The present research was undertaken to study the acute toxicity of binary mixtures of Ni, Cu, Zn, and Cd to the freshwater organism, Daphnia magna. The experimental approach included single and binary metal toxicity tests based on… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This thesis focused on expanding knowledge of Hybomitra, Chrysops and Tabanus (Diptera: Tabanidae) distributions north of Lake Nipigon, Ontario, in a managed boreal forest. As land use and climate changes accelerate, there is increased pressure to increase knowledge from which to monitor changes. In 2011 and 2012, 8928 individuals representing, 44 species were captured using sweep… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Cis-isomers of the cytokinin plant hormone family are thought to have low activity or impact on plant growth and development. Mutants with independent silencing of the pathway leading to cis-CK (cis-cytokinin) were investigated at the phenotype and metabolite levels. Phenotypic deviations were noted in trichome development, fresh weight, rosette diameter, number of non-rosette leaves,… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Fisheries assessment and management approaches have historically focused on individual species over relatively short timeframes. These approaches are being improved upon by considering the potential effects of both broader ecological and evolutionary processes. However, only recently has the question been raised of how ecological and evolutionary processes might interact to further… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Historically, entrances have been used for passage between two separate temperature environments, such as moving from inside to outside of a building. Energy loss through entrances is a cause for concern, as it has been known to increase energy consumption to replace the lost energy; and with the exchange of air masses and cold air entering the building, human discomfort may occur. In… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Pieper, Sara Jean, Thesis advisor (ths): Dorken, Marcel, Thesis advisor (ths): Freeland, Joanna, Degree committee member (dgc): Bowman, Jeff, Degree committee member (dgc): Wilson, Chris, Degree granting institution (dgg): Trent University Abstract: <p>Interspecific hybridization is an important evolutionary process which can contribute to the invasiveness of species complexes. In this dissertation I used the hybridizing species complex of cattails (Typha spp., Typhaceae) to explore some of the processes that could contribute to hybridization rates. Cattails in northeastern North America comprise the native T. latifolia, the non-native… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Three long-term mark and recapture/resight data sets of individually marked</p><p>Semipalmated Plovers (Charadrius semipalmatus) were analyzed using Cormack-Jolly-</p><p>Seber models. Data came from two breeding populations (Churchill, Manitoba, Canada,</p><p>n=982, and Egg Island, Alaska, USA, n=84) and one overwintering population</p><p>(… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>While the harvest of mammals is monitored in each jurisdiction across Canada and the USA, there has been no analysis of this wild harvest at a continental scale across North America. The recreational wild harvest of large mammals varies geographically across North America, and I hypothesized that this variation is influenced by both anthropogenic and other environmental factors on the… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Forestalling biodiversity loss through the establishment of protected areas is a universally accepted conservation strategy, yet despite established guidelines for protected area coverage and placement, much of the world is currently failing to meet its commitments to conservation planning and landscape protection. Calls for the United States to protect more land usually focus on the… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Soil is an essential natural resource that supports provisioning services such as agriculture, silviculture, and mining. However, there is limited knowledge on forest soil properties across Canada. Digital soil mapping may be used to fill these data gaps, as it can predict soil properties in areas with limited observations. The focus of this study was to develop predictive maps of select… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Due to their effective antibacterial and antifungal properties, silver nanoparticles (AgNPs) have quickly become the most commonly used nanomaterial, with applications in industry, medicine and consumer products. This increased use of AgNPs over the past decade will inevitably result in an elevated release of nanoparticles into the environment, highlighting the importance of assessing… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Elemental selenium has been extensively quantitatively measured in sediments; however, its physical composition is largely unknown, despite it being the dominant selenium species in some reducing environments. Here, for the first time, it is shown that small, cyclic selenium compounds can account for a quantitatively-relevant fraction of the total elemental selenium present. </p>… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Populations have long been delineated by physical barriers that appear to limit reproduction, yet increasingly genetic analysis reveal these delineations to be inaccurate. The eastern and mid-continent populations of sandhill cranes are expanding ranges which is leading to convergence and warrants investigation of the genetic structure between the two populations. Obtaining blood or… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Blanchard, Dane Alexander, Thesis advisor (ths): Aherne, Julian, Degree committee member (dgc): Watmough, Shaun, Degree committee member (dgc): Sager, Eric P.S., Degree committee member (dgc): McKenna Neuman, Cheryl L, Degree granting institution (dgg): Trent University Abstract: <p>Recent developments at an aluminum (Al) smelter in Kitimat, BC resulted in a permitted increase of 27 to 42 tonnes of sulphur dioxide (SO2) emissions per day. Gaseous SO2 is a pollutant known to contribute to acidic deposition through processes of wet and dry deposition and can additionally react in-atmosphere to form particulate sulphate (pSO42-). Between June 2017 to October 2018, an… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Environmental DNA (eDNA) is rapidly becoming an established method for the detection of species in aquatic systems and has been suggested as a promising tool to estimate species abundance. However, the strength of the relationship between eDNA concentrations and taxon abundance (density/biomass) can vary widely between species. I investigated the relationship between eDNA concentration… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Sajer, Bayan, Thesis advisor (ths): Yee, Janet, Degree committee member (dgc): Rafferty, Steven, Degree committee member (dgc): Bates, Holly, Degree committee member (dgc): Brunetti, Craig, Degree granting institution (dgg): Trent University Abstract: <p>The parasitic protist Giardia intestinalis has five heme proteins: a flavohemoglobin and several isotypes of cytochrome b5. While the flavohemoglobin has a role in counteracting nitric oxide, the functions of the cytochromes (gCYTb5s) are unknown. In this study, the protein level and cellular localization of three gCYTB5 isotypes (gCYTb5-I, II and III) and flavohemoglobin were examined… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Upland Sandpipers (Bartramia longicauda), like many grassland birds, are undergoing population decline in parts of their range. Habitat fragmentation and change have been hypothesized as potential causes of decline. I used citizen-science occurrence data from Wildlife Preservation Canada's Adopt-A-Shrike Loggerhead Shrike (Lanius ludovicianus) program in conjunction with validation… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Predation risk can elicit a range of responses in prey, but to date little is known about breadth of potential responses that may arise under realistic field conditions and how such responses are linked, leaving a fragmented picture of risk-related consequences on individuals. We increased predation risk in free-ranging snowshoe hares (Lepus americanus) during two consecutive summers by… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Competition is known to impact population dynamics through both indirect and direct interactions, and direct interactions can often lead to injury in one or both parties. As such, response to injury through tissue regeneration can be important for surviving post-competitive interaction. However, the impacts of outside factors like temperature and genome size (e.g. polyploidy) are not… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Vezsenyi, Kathryn Anne, Thesis advisor (ths): Beresford, David V, Thesis advisor (ths): Schaefer, James A, Degree committee member (dgc): Skevington, Jeffrey H, Degree committee member (dgc): Crins, William, Degree granting institution (dgg): Trent University Abstract: <p>Syrphids, also known as hover flies (Diptera: Syrphidae) are a diverse and widespread family of flies. Here, I report on their distributions from a previously understudied region, the far north of Ontario, as well as Akimiski Island, Nunavut. I used samples collected through a variety of projects to update known range and provincial records for over a hundred species, bringing into… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Wynia, Abby, Thesis advisor (ths): Whillans, Thomas H., Thesis advisor (ths): Doka, Susan E., Degree committee member (dgc): de Kerckhove, Dak T., Degree committee member (dgc): Sager, Eric P.S., Degree granting institution (dgg): Trent University Abstract: <p>Invasive Phragmites australis ssp. australis (herein "Phragmites") has established and rapidly spread throughout many coastal areas of the Great Lakes. Known to displace native vegetation communities as it forms large, monotypic stands, Phragmites has a bad reputation when it comes to losses of biodiversity and habitat provision for wildlife. However, the extent to which… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Coldwater streams are becoming increasingly impacted due to urbanization. Using environmental surveys, mark-recapture and telemetry, I assessed factors influencing seasonal brook trout (Salvelinus fontinalis) habitat use and movement in urban headwater streams in central Ontario between 2017-18. Generalized additive models were used to assess which habitat variables best explained… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Ustilago maydis (D.C.) Corda is a biotrophic pathogen that secretes effectors to establish and maintain a relationship with its host, Zea mays. In this pathosystem, the molecular function of effectors is well-studied, but the regulation of effector gene expression remains largely unknown. This study characterized Zfp1, a putative U. maydis Zn(II)2Cys6 transcription factor, as a modulator… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Glucocorticoids (e.g., corticosterone (CORT)) are hypothesized to mediate decisions regarding reproductive investment during breeding, but the directionality of the relationship is not clear. The CORT-fitness hypothesis posits that high levels of CORT arise from challenging environmental conditions in which an individual will conserve resources for future reproduction or self-maintenance… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Interspecific hybridization rates can vary depending on genomic compatibilities between progenitors, while subsequent hybrid spread can vary depending on hybrid performance and habitat availability for hybrid establishment and persistence. As a result, hybridization rates and hybrid frequencies can vary across regions of parental sympatry. In areas around the Laurentian Great Lakes,… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>To investigate cytokinins (CKs) in nematodes, CK profiles of a free-living Caenorhabditis elegans and a plant parasitic Heterodera glycines (soybean cyst nematode, SCN) were determined at the egg and larval stages. SCN had higher total CK level than C. elegans; however, CKs in SCN were mostly inactive precursors, whereas C. elegans had more bioactive forms. This is the first study to… more Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Microfibres, which are threadlike particles < 5 mm, are the most common type of microplastic reported in the environment. However, few studies have focused on their abundance in background natural environments. This study assessed the abundance of microfibres in rainfall samples (from four precipitation monitoring stations) and across three headwater lake catchments that were in… more
