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Ophidiomycosis (snake fungal disease) is caused by the pathogen Ophidiomyces ophiodiicola. Infected snakes exhibit dermal lesions, occasional systemic infections, and, in some cases, mortality. We studied snakes at Rondeau Provincial Park, Ontario, Canada, to explore whether ophidiomycosis develops during brumation or year-round. Throughout their active season, we quantified the prevalence of clinical signs of the disease on snakes and conducted qPCR of skin swabs to determine the prevalence of O. ophiodiicola on snakes. Prevalence of O. ophiodiicola and disease symptoms were highest on eastern foxsnakes (Pantherophis vulpinus) and very rare on other snake species. In P. vulpinus, pathogen and clinical sign prevalence was highest, directly after emergence from overwintering, with the majority of P. vulpinus being able to resolve clinical signs of ophidiomycosis by the return of winter. When we analyzed the survivorship of P. vulpinus we determined that the likelihood of a snake dying with ophidiomycosis is similar to a snake dying without ophidiomycosis. Given that P. vulpinus were the most affected species at our study site, ophidiomycosis does not appear to pose an imminent threat to our study population of P. vulpinus under current conditions.

Author Keywords: Eastern Foxsnake, Fitness, Ophidiomycosis, Pantherophis vulpinus, Seasonal trends, Snake fungal disease

There are many barriers facing new, sustainably-focused, agriculturalists in Canada including access to land, capital, markets and practical training. These challenges are compounded by the flawed but powerful figure of the industrial agriculture model, a rapidly aging farmer population, changing demographics, and subsequent loss of valuable, place-based agricultural knowledge. This thesis argues that there is a need for innovative formal education programs that combine traditional classroom with practical hands-on learning in collaboration with local experts. As such, this exploratory case study looks at how a farm incubator can function as a site for experiential education and a means of addressing some of the barriers to entry faced by new agroecological farmers. The findings show that those seeking experiential sustainable agriculture education benefit greatly from having a site, such as a farm incubator, to learn the skills that accompany their knowledge while building their agricultural community and increasing their confidence.

Author Keywords: agroecology, experiential learning, farm incubators, social learning, sustainable agriculture and food systems education, transdsciplinary

One possible solution to acidification and losses of base cations in central Ontario forest soils may be the application of wood ash. Wood ash is generally high in pH and contains large amounts of calcium (Ca) and other nutrients essential for ecosystem health, however it also contains trace metals. Understanding the chemistry of soils following ash application to forests is crucial for future policy recommendations and remediation efforts. In this study, soil and soil water chemistry was measured at two acidic forest sites in central Ontario. Sugar maple (Acer saccharum, Marsh.) seedling growth and chemistry, as well as understory vegetation composition, were also measured. At site one, plots (2 m x 2 m) were established with sugar maple, white pine (Pinus strobus L.) and yellow birch (Betula alleghaniensis Britt.) residential wood ash treatments and applied at rates of 0 and 6 Mg ha-1. The effects of residential wood ash on soil and understory vegetation were measured three- and 12-months following ash addition. At site two, plots (5 m x 5 m) were established with both fly and bottom industrial grade bark ash treatments of 0, 4 and 8 Mg ha-1 (n=4), and tension lysimeters were positioned in each plot at 30, 50, and 100 cm depths. The effects of industrial grade wood ash on soil, soil water and understory vegetation were measured four years following ash addition. Metal concentrations in the ashes were generally low but were higher in the fly ash and yellow birch ash types. At site one, significant increase in soil pH, and Ca and magnesium (Mg) concentrations were observed after three months, however changes varied by treatment. Some metal concentrations increased in the upper organic horizons, but metals were likely immobilized in the soil due to increases in soil pH, electrical conductivity (EC) and high organic matter content of the soil. After one year, changes to metal concentrations in soils could be seen in mineral horizons, and a few metals (aluminum (Al), zinc (Zn), copper (Cu), chromium (Cr), strontium (Sr)) increased in treatment plots. At site two, the effects of industrial-grade bark ashes on soil pH could still be seen after four years and soil water metal concentrations were not elevated relative to controls. Changes to understory vegetation composition following ash application were observed, but ash addition had no significant effect on sugar maple seedling growth (root:shoot ratio) and did not lead to significant increases in foliar metal concentrations. There were significant differences in root chemistry, suggesting metal translocation and uptake could be restricted. Mass balance estimates indicate that the organic horizon is a sink for all metals and simulated drought in this horizon led to a decrease in soil pH and increase in soil water metal concentration, but this occurred in all treatments including control. These results suggest that application of industrial and residential wood ash in moderate doses with trace metal concentrations below or near regulatory limits will increase soil pH and base cation concentrations, as well as increase seedling tissue nutrient concentrations in northern hardwood forest soils. However, depending on the parent material of the ash, increased metal availability can also occur.

Author Keywords: Acer saccharum, calcium decline, forest soil amendment, Haliburton Forest and Wildlife Reserve, heavy metal, wood ash

Water storage is a fundamental component of drainage basins, controlling the synchronization between precipitation input and streamflow output. The ability of a drainage basin to store water and regulate streamflow may mediate sensitivity to climate and land cover change. There is currently no agreement on the best way to quantify basin storage. This study compares results of a combined hydrometric and isotopic approach for characterizing inter-basin differences in storage across the Oak Ridges Moraine (ORM) in southern Ontario. The ratio of the standard deviation of the stable isotope signature of streamflow relative to that of precipitation has been shown to be inversely proportional to mean water transit times, with smaller ratios indicating longer water transit times and implying greater storage. Stable isotope standard deviation ratios were inversely related to baseflow index values. Basins demonstrating longer transit times were associated with hydrological characteristics that promote infiltration and recharge of storage.

Author Keywords: baseflow, basin storage, climate change, mean transit time, Oak Ridges Moraine, stable isotopes

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 (gCYTB5-III) is particularly fascinating for its unusual location in the nuclei of Giardia. This thesis reports the optimization of recombinant gCYTB5-III overexpression for structural studies by NMR spectroscopy. Vital optimization factors for isotope labelling were first identified, finding that auto-induction promotes the optimization of many other conditions, such as colony selection, starter cultures, media components, temperature, pH and aeration. Optimized conditions were then applied to the expression and NMR spectroscopy of isotope-labelled gCYTB5-III and bovine cytochrome b5 as a control. These results can be extended to other heme proteins and will expand our biochemical knowledge of Giardia.

Author Keywords: Auto-induction, Cytochrome b5, Giardia intestinalis, Isotope Labelling, Nuclear Magnetic Resonance Spectroscopy, Recombinant Protein

This thesis presents a palaeotopographic reconstruction of the Burleigh Bay region of Stony Lake (Kawartha Lakes Region, Ontario) from 12,600 cal BP to present. The paleotopographic reconstructions are used to model paleoshoreline locations and archaeological site potential for the Late Paleoindian and early Archaic periods. Isostatic rebound following the end of the last glacial period has altered the topography in the region and water levels are now artificially managed by dams constructed in the 1830s. I completed a high-resolution bathymetric survey using a kayak equiped with a GPS coupled single-beam sonar. Utilizing GIS technology and isostatic rebound response surface models, I created paleotopographic reconstructions for 12,600 cal BP, 11,500 cal BP, 7,000 cal BP, 5,700 cal BP, and present. Results show that water levels in Burleigh Bay have been regressing over time until dam construction. Early site potential is centered in northern inland areas. Site potential following 7,000 cal BP is concentrated in northern areas flooded by the dam. Based on the reconstructions, surveys in lacustrine granite shield regions that follow the Ontario Standards and Guidelines for Consultant Archaeologists risk missing areas of high archaeological potential for early sites in these environments. Paleolandscape reconstructions would alleviate this issue by modeling paleoshoreline changes over time.

Author Keywords: Canadian Shield, Early Archaic, Isostatic Rebound, Kawartha Lakes, Late Paleoindian, Paleolandscape

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 2019 and examined habitat selection and foraging behaviour in Dunlin (Calidris alpina), Sanderling (Calidris alba), Semipalmated Plovers (Charadrius semipalmatus), and Piping Plovers (Charadrius melodus). Area, tidal stage, and invertebrate prey availability were important determinants of shorebird abundance, behaviour, and distribution. My study highlights the importance of Bulls Island's habitat heterogeneity to supporting a diverse community of non-breeding shorebirds. Considering both the high rate of erosion and the increased frequency of disturbance along the shoreline of the island, intertidal habitats should be monitored to predict negative effects of changes in habitat composition and area on non-breeding shorebirds.

Author Keywords: foraging behaviour, habitat loss, habitat selection, invertebrate prey, non-breeding, shorebirds

I investigated if spatio-temporal behaviour of grey wolves (Canis lupus) determined via GPS collar locations could be used to discriminate predation events generally, and among prey species, in Prince Albert National Park during winter, 2013-2017. I used characteristics of spatio-temporal GPS clusters to develop a predictive mixed-effect logistic regression model of which spatial clusters of locations were wolf kill sites. The model suffered a 60 % omission error when tested with reserved data due to the prevalence of deer kills with correspondingly low handling time. Next, I found a multivariate difference in the percentage of habitat classes used by wolves in the 2 hours preceding predation events of different prey species, suggesting that wolf habitat use reflects prey selection at a fine-scale. My results highlight the difficulty and future potential for remoting discriminating wolf predation events via GPS collar locations in multi-prey ecosystems.

Author Keywords: Canis lupus, GPS clusters, GPS collars, grey wolf, habitat use, predation

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 species, wherein S. catenatus was detected less often and under a more specific set of sampling conditions. Correspondingly, detection trials with S. catenatus found a high non-detection rate, while detection trials with artificial models suggest that regional differences in detection probability are driven by variation in population density and habitat use. Our results suggest that current monitoring efforts are not sufficient, and that S. catenatus is frequently undetected. Accordingly, we highlight the importance of species-specific monitoring protocols when monitoring rare and elusive species, and recommend a multi-faceted approach that estimates detection probability and identifies species-specific challenges to monitoring.

Author Keywords: detection probability, elusive species, monitoring programs, non-detection, S. catenatus, snakes

Academic procrastination is analogous to a common cold: pervasive and with no established cure. Students experience repercussions that are not inclusive to academic performance, but rather, are experienced across mental, physical, social and emotional domains as well. While this necessitates treatment, much of the behaviour has yet to be explained. In the current study, a state approach was integrated to explore procrastination in terms of the Yerkes-Dodson paradigm. Procrastination was hypothesized to arise for one of two reasons: students are either too low or too high in anxiety. A sample of 847 Ontario undergraduate students completed measures of procrastination, state-anxiety, personality, and self-regulation. Results suggest 88% of students procrastinate regularly, and contrary to what was hypothesized, procrastination and anxiety were linearly related. Independent t-tests establish that relative to non-procrastinators, procrastinators are significantly more emotionally and biologically dysregulated and less socially integrated. Factor analysis demonstrated three central reasons contributing to procrastination, which were used as the basis to establish types of procrastination: social (n=61), self-doubt (n=70) and low-energy (n=76) procrastinators. Results indicate divergences across procrastination type with respect to personality as well as biological, affective and social domains. Findings also inform that the expression of procrastination, varies across student. Overall, findings suggest that academic interventions should acknowledge and address the variability among procrastinators.

Author Keywords: ACADEMIC PROCRASTINATION, ANXIETY, PERSONALITY, SELF-REGULATION