Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Muskrat populations are declining across North America. In recent decades, hybrid cattail Typha x glauca has been invading wetlands in North America. This invasion is degrading wetland habitat, leading to reduced interspersion of water and vegetation. Muskrats are wetland-obligates and their populations are positively linked to marsh interspersion. Therefore, muskrat populations may be… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Hybridization contributes to the genetic diversity and can impact speciation. This study investigates the genetic evidence of recent hybridization under climate change in sympatric populations of northern and southern flying squirrels in Ontario. Using low-coverage whole-genome sequences, my research examines the existing population structure and measures the genomic variation of the… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Acoustic communication is vital for mediating interactions between individuals and their environment. From echolocating bats to isolated rodent pups, ultrasonic vocalizations are a useful mechanism for producing localized and cryptic acoustic signals. Flying squirrels have been demonstrated to produce almost exclusively ultrasonic calls which is rare in both squirrels and mammals, though… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Northern flying squirrels (NFS) are mycophagous specialists (fungi-dominated diet) thatmay be displaced with southern flying squirrel (SFS) range expansion, thereby limiting
fungal dispersal in forest communities. To understand the implications of squirrel
species turnover on mycophagy, we investigated the home ranges of both flying squirrel
species who are living in stable sympatry. We… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Solmundson, Kirsten, Thesis advisor (ths): Wilson, Paul, Thesis advisor (ths): Bowman, Jeff, Degree committee member (dgc): Patterson, Brent, Degree committee member (dgc): Manseau, Micheline, Degree granting institution (dgg): Trent University Abstract: <p>Globally, wildlife populations are experiencing increasing rates of range loss, population decline, and extinction. Caribou (Rangifer tarandus) have experienced dramatic declines in both range and population size across Canada over the past century. Boreal caribou (R. t. caribou), one of twelve Designatable Units, have lost approximately half of their historic range in the last 150 years… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Wetlands are highly susceptible to the invasion of invasive species. The invasive hybrid cattail (Typha × glauca) is prevalent in the southeastern Prairie Pothole Region (PPR) wetlands. However, concerns arise about its recent proliferation in the northwestern PPR without maternal T. angustifolia. To determine taxonomic distribution, I used species-specific PCR-RFLP and microsatellite… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Advanced generation/backcrossed (non-F1) hybrids can be challenging to identify when their traits are similar to those of parental taxa, F1 hybrids, or both. This is particularly evident in the North American hybrid zone involving Typha latifolia, T. angustifolia, F1 T. × glauca and non-F1 hybrids. Cattails are challenging to differentiate based on gross morphological characteristics.… more
Year: 2022, 2022
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): McFarlane, Samantha Amy, Thesis advisor (ths): Wilson, Paul J, Thesis advisor (ths): Manseau, Micheline, Degree committee member (dgc): Bowman, Jeff, Degree committee member (dgc): Steenweg, Robin, Degree granting institution (dgg): Trent University Abstract: <p>Variation in habitat quality and disturbance levels can strongly influence a species' distribution, leading to spatial variation in population density and influencing population dynamics. It is therefore critical to understand how density can lead to variability in demographic responses for effective conservation and recovery of species. My dissertation illustrates how density and… more
Year: 2022, 2022
Member of: Trent University Graduate Thesis Collection
Abstract: <p>AbstractDifferences and similarities in exploration and risk-taking behaviours
of two Myotis bat species.
Laura Michele Scott
Behaviours that are repeatable across circumstances and time determine an individual's personality. Personality and behavioural variation are subject to selective pressures, including risks related to the use of different habitat types. I explored the… more
Year: 2022, 2022
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Increased plant size is expected to have negative consequences for mating by increasing pollen transfer among the same plant. However, recent theoretical studies have demonstrated that this may not be true for clonal plants. Instead, clonal expansion could enhance outcrossing opportunities without increasing selfing by reducing distances to potential mates. I investigated how the spatial… more
Year: 2022, 2022
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Roosts offer bats protection from predators, shelter from external environmental conditions, and a space where sociality, mating, and the rearing of young can occur. However, knowledge gaps still remain for many forest roosting species, such as the little brown bat (Myotis lucifugus) surrounding what roosts are selected, and what variables are influential at differing scales of selection… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The length of photoperiod can alter circadian rhythms and change fat depot mass whencombined with environmental temperatures below thermoneutral. To isolate photoperiod effects, we compared the effects of long and short photoperiod exposure at thermoneutrality in photoperiod sensitive, F1 generation adult male white-footed mice (P. leucopus). Mice were housed in long-day or short-day… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>As wild turkeys (Meleagris gallopavo silvestris) move farther north, informed management decisions are critical to support the sustainability of this reintroduced species. We tracked roost tree selection and patterns of the network of roost trees, for wild turkeys, over 2 years in Peterborough, ON, using GPS and VHF transmitters. Wild turkeys showed preference for taller and larger roost… more
Year: 2020, 2020
Member of: Trent University Graduate Thesis Collection
Abstract: <p>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… more
Year: 2020, 2020
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The ability of animal populations to compensate for harvest mortality provides the basis for sustainable harvesting. Coyote populations are resilient to exploitation, but the underlying mechanisms of compensation and how they inter-relate are not fully understood. Moreover, deficiencies in the quality and quantity of information about eastern coyotes preclude effective management. I… more
Year: 2020, 2020
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Munro, Keith, Thesis advisor (ths): Patterson, Brent R, Thesis advisor (ths): Pond, Bruce A, Degree committee member (dgc): Schaefer, James, Degree committee member (dgc): Bowman, Jeff, Degree granting institution (dgg): Trent University Abstract: <p>The primary method used to maintain white-tailed deer (Odocoileus virginianus) populations at densities that are ecologically, economically, socially, and culturally sustainable is hunter harvest. This method considers only the removal of animals from the population (the direct effect) and does not conventionally consider the costs imposed on deer as they adopt hunter avoidance… more
Year: 2020, 2020
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): MacDonald, Amelia J., Thesis advisor (ths): Nol, Erica, Thesis advisor (ths): Smith, Paul A, Degree committee member (dgc): Murray, Dennis, Degree committee member (dgc): Bowman, Jeff, Degree granting institution (dgg): Trent University Abstract: <p>Many shorebirds rely on small numbers of staging sites during long annual migrations. Numerous species are declining and understanding the importance of staging sites is critical to successful conservation. We surveyed endangered rufa Red Knots staging in James Bay, Ontario during southbound migration from 2009 to 2018. We used an integrated population model to estimate passage… more
Year: 2020, 2020
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Species ranges are changing and the rate at which the climate is warming is faster than anything previously seen in the past, consequently species will need to adapt quickly, track the climate or perish. Cold adapted terrestrial species are the most vulnerable, because they are limited by the availability of land at the cold edge of their range. This means that many alpine, boreal and… 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>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
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>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: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Introgressive hybridization between northern (Glaucomys sabrinus) and southern flying squirrels (G. volans) has been observed in some areas of Canada and the USA. However, existing molecular markers lack the resolution to discriminate late-generation introgressants and describe the extent to which hybridization influences the Glaucomys gene pool. I report the first North American flying… more
Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Numerous prey taxa employ defensive postures for protection against attack by predators. Defensive postures mitigate predation risk at various stages of the predator-prey sequence, including through crypsis, mimicry, thanatosis, aposematism, and deflection. In terrestrial salamanders, defensive postures may be aposematic, or deflect attacks away from vital body parts and towards the tail… 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
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: 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
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
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>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: 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>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>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
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>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: 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
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
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>I determined the direct influence of single-tree selection harvesting on the daily nest survival rates and nest success of 5 focal bird species within a monotypic red pine (Pinus resinosa) plantation on the western edge of the Oak Ridges Moraine in southern Ontario, Canada. I located and monitored 290 nests during the 2012 and 2013 breeding season. I used the logistic-exposure method to… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Lalor, Jillian L., Thesis advisor (ths): Bowman, Jeff, Thesis advisor (ths): Wilson, Paul J, Degree committee member (dgc): Schulte-Hostedde, Albrecht, Degree committee member (dgc): Murray, Dennis, Degree granting institution (dgg): Trent University Abstract: <p>While hybridization between distinct taxa can have undesirable implications, it can also result in increased genetic variability and potentially, the exchange of adaptive genes or traits. Adaptive variation acquired through introgressive hybridization may be particularly advantageous for species facing rapid environmental change. I investigated a novel, climate change-induced hybrid zone… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The Pearl River Estuary (PRE) and eastern Taiwan Strait (ETS) populations of Indo-Pacific humpback dolphins (Sousa chinensis) contain ~600 and 100 catalogued individuals, respectively. Population demography is important for conservation actions but few animals have been sexed by conventional methods. Longitudinal analysis of tooth-rake scars on dorsal fins showed scars disappear within 7… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Since their successful reintroduction, the eastern wild turkey <italic>(Meleagris gallopavo silvestris)</italic> has expanded its range north. Due to different and potentially more severe limiting factors, management approaches generalized from studies within the historical range may not be appropriate to apply to northern populations. To better understand northern wild… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>I used a GIS raster layer of an area in the Churchill, Manitoba region to investigate the effect of breeding habitat on demography and density of Whimbrel from 2010 through 2013. Program MARK was used to quantify adult and daily nest survival. Apparent annual survival of 0.73 ± 0.06 SE (95% CI = 0.60-0.83) did not significantly differ between sexes or habitats and was lower than expected… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Majchrzak, Yasmine Nicole, Thesis advisor (ths): Burness, Gary, Degree committee member (dgc): Mastromonaco, Gabriela, Degree committee member (dgc): Murray, Dennis, Degree committee member (dgc): Bowman, Jeff, Degree granting institution (dgg): Trent University Abstract: <p>Many facilities attempt to alleviate the risk of chronic stress in captivity by providing environmental enrichment shown to minimize behavioural disorders and stress in several species. One potential form of enrichment used in zoos is training animals to perform rides for guests, however, the effect of this activity on the welfare of individual animals has never been examined. I… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The structure and composition of the landscape can facilitate or impede gene flow, which can have important consequences because genetically isolated groups of individuals may be prone to inbreeding depression and possible extinction. My dissertation examines how landscape structure influences spatial patterns of genetic differentiation and diversity of American marten (<italic>… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Hornseth, Megan L., Thesis advisor (ths): Murray, Dennis L., Degree committee member (dgc): Bowman, Jeff, Degree committee member (dgc): Fortin, Marie-Josee, Degree committee member (dgc): Ray, Justina, Degree granting institution (dgg): Trent University Abstract: <p>Current major issues in conservation biology include habitat loss, fragmentation and population over-exploitation. Animals can respond to landscape change through behavioural flexibility, allowing individuals to persist in disturbed landscapes. Individual behaviour has only recently been explicitly included in population models. Carnivores may be sensitive to changing landscapes due to… more