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 Full Text: Making eDNA count: Using environmental DNA (eDNA) to quantify relative larval amphibian abundance A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Faculty of Arts …
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 Full Text: CHARACTERIZATION OF A Zn(II)2Cys6 TRANSCRIPTION FACTOR IN Ustilago maydis AND ITS ROLE IN PATHOGENESIS A dissertation submitted to the Committee of Graduate Studies in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the …
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 Full Text: THE ROLE OF CORTICOSTERONE IN REPRODUCTIVE EFFORT AND BREEDING SUCCESS IN TREE SWALLOWS A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Faculty of Arts and …
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 Full Text: INVESTIGATING THE REGIONAL VARIATION IN FREQUENCIES OF THE INVASIVE HYBRID CATTAIL, TYPHA × GLAUCA A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Faculty of …
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 Full Text: Fish and invertebrate use of invasive Phragmites in a Great Lakes freshwater delta A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfilment of the Requirements for the Degree of Master of Science in the Faculty of Arts and Sciences …
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 Full Text: SEASONAL HABITAT USE AND MOVEMENT OF NATIVE BROOK TROUT (SALVELINUS FONTINALIS) IN URBAN HEADWATER STREAMS A Thesis Submitted to the Committee of Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in the …
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 Full Text: Syrphidae (Diptera) of northern Ontario and Akimiski Island, Nunavut: new diversity records, trap analysis, and DNA barcoding A Thesis Submitted to the Committee of Graduate Studies in Partial Fulfillment for the Degree of Master of Science in the Faculty …
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 Full Text: How Abiotic and Biotic Factors Can Alter the Competitive Landscape in an Aggressive Species Complex (Genus: Ambystoma) A thesis submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirement for the Degree of Master of Science in …
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 Full Text: AN INVESTIGATION OF RARE EARTH ELEMENT PATTERNS AND AN APPLICATION OF USING ZN AND CD ISOTOPE RATIOS IN OYSTERS TO IDENTIFY CONTAMINATION SOURCES IN AN ESTUARY IN SOUTHERN CHINA A Thesis Submitted the Committee on Graduate Studies in Partial Fulfillment …
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 Full Text: ASSESSING MOLECULAR AND ECOLOGICAL DIFFERENTIATION IN WILD CARNIVORES A Thesis Submitted to the Committee on Graduate Studies In Partial Fulfillment of the Requirements for the Degree of Master of Science in the Faculty of Arts and Science Trent …
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 Full Text: Fingerprinting of dissolved organic matter and copper ligands in the Canadian Arctic and North Pacific Ocean A thesis submitted to the Committee of Graduate Studies in partial fulfillment of the requirements for the degree of Master of Science in the …
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 Full Text: Molecular Composition of Dissolved Organic Matter Controls Metal Speciation and Microbial Uptake A dissertation submitted to the Committee of Graduate Studies in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the faculty …
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 Full Text: CONTEMPORARY ADAPTIVE SHIFTS IN THE PHYSIOLOGY AND LIFE HISTORY OF PUMPKINSEED (LEPOMIS GIBBOSUS) INTRODUCED INTO A WARM CLIMATE. A Dissertation Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of …
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 Full Text: SHOREBIRD HABITAT USE AND FORAGING ECOLOGY ON BULLS ISLAND, SOUTH CAROLINA DURING THE NON-BREEDING SEASON A Thesis Submitted to the Committee of Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Faculty …
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 Full Text: A multi-faceted approach to evaluating the detection probability of an elusive snake (Sistrurus catenatus) A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirement for the Degree of Master of Science in the Faculty …
Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Levasseur, Patrick, Thesis advisor (ths): Watmough, Shaun, Degree committee member (dgc): Aherne, Julian, Degree committee member (dgc): Eimers, Catherine, Degree committee member (dgc): Whitfield, Colin, Degree granting institution (dgg): Trent University Abstract: <p>In 2012, the Rio Tinto aluminum smelter in Kitimat, British Columbia increased sulphur dioxide (SO2) emissions from 27 to 42 tonnes/day. An initial study was conducted to investigate the effect of the increased sulphur (S) deposition on forest soils. A key uncertainty of the initial study was mineral surface area estimations that were applied to critical load calculations. The current… more Full Text: Estimating mineral surface area and acid sensitivity of forest soils in, Kitimat, British Columbia A thesis submitted to the Committee of Graduate Studies in partial fulfillment of the requirements for the degree of Master of Science in the Faculty of …
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 Full Text: Ground-truthing effective population size estimators using long-term population data from inland salmonid populations A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in …
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 Full Text: STOICHIOMETRIC FOOD QUALITY AFFECTS RESPONSES OF DAPHNIA TO PREDATOR-DERIVED CHEMICAL CUES A Thesis submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Faculty of Arts and …
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 Full Text: HYDROLOGICAL AND FLOODING EFFECTS ON STREAM NUTRIENT LEVELS A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Faculty of Arts and Science Trent University …
Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): McClenaghan, Beverly, Thesis advisor (ths): Nol, Erica, Degree committee member (dgc): Nocera, Joseph J, Degree committee member (dgc): Beresford, David V, Degree committee member (dgc): Kerr, K, Degree granting institution (dgg): Trent University Abstract: <p>Barn Swallow (Hirundo rustica) populations have declined in North America over the past 40 years and they are listed as Threatened in Ontario, Canada. Changes in the food supply have been hypothesized as a potential cause of this population decline. I used DNA barcoding to investigate the diet and food supply of Barn Swallows and to determine if the food supply affects their reproductive… more Full Text: USING DNA BARCODING TO INVESTIGATE THE DIET AND FOOD SUPPLY OF A DECLINING AERIAL INSECTIVORE, THE BARN SWALLOW (Hirundo rustica) A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master …
