Theses (Geography)

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    Population ecology of mountain goats in relation to climate, weather and snow avalanches
    (2025) White, Kevin Scott; Darimont, Chris T.
    Weather and climate exert profound influences on wildlife populations. In mountain environments climate is changing rapidly, compared with surrounding lowland areas, highlighting the importance of understanding the population ecology of species inhabiting these sensitive and biodiverse systems. My dissertation research focused on how weather and climate, and related phenomena (i.e. snow avalanches), influence the population ecology of mountain goats – a sentinel species on mountain environments. I used long-term field data collected from individually marked animals (421 individuals over 17 years across 4 study areas in coastal Alaska) combined with remote-sensing environmental data to assess a suite of research questions. First, however, I synthesized existing information about how mountain goats are influenced by weather and climate in order to comprehensively understand the state of our knowledge and identify knowledge gaps (Chapter 2). Next, I examined how climate and life-history trade-offs shape mountain goat reproductive demography (Chapter 3). These analyses revealed age-specific patterns in reproductive performance were negatively influenced by previous parturition success, late-winter snow depth and summer temperature. Highlighting the importance of intrinsic and extrinsic factors on reproduction, these results also filled an important data gap by enabling parameterization and implementation of mountain goat population modeling simulations used to evaluate relative strength of winter vs summer effects and later analyses (described below). The remainder of my research focused on examining the extent that snow avalanches represent a climate-linked driver of mountain goat populations. In Chapter 4, principal findings revealed that avalanches comprise a major source of mortality (36% of all mortalities, on average) and can remove up to 22% of a population annually. Given the low realized population growth rate previously reported for mountain goats (i.e. 1-4%), such impacts may exert significant demographic consequences. To quantify such impacts, I next developed and implemented a population modeling approach to explicitly examine and quantify how avalanches, across a range of scenarios, influence population growth and dynamics, including recovery times (Chapter 5). Ultimately, I determined that mountain goats can sustain modest population growth (1.5%) during average avalanche conditions, but during severe years (i.e. when 23% of a population dies from avalanches) populations can experience significant declines (15%) that require extended periods (11 years, or 1.5 mountain goat generations) for recovery to baseline levels. Overall, my research contributes several dimensions of new knowledge about how weather and climate-linked factors influence mountain goats populations, and offer important insights about the functionality of mountain ecosystems in the face of changing climate conditions.
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    Optimization of C- and L-band synthetic aperture radar for all-season rift detection: A case study of the Larsen C Ice Shelf
    (2025) McDougall, Kali Ann; Scharien, Randall
    More than half of ice mass loss from Antarctica occurs through calving of large tabular icebergs along rifts at the outer margins of ice shelves, which can lead to ice shelf destabilization and collapse. Synthetic aperture radar (SAR) sensors provide the greatest potential utility for the study of calving-related mechanisms by offering year-round, all-weather imaging and penetration of surface snow. To fully utilize SAR for rift detection, the constraints on fracture detectability posed by surface melt, and radar frequency and polarization, must be characterized. We examined dual-pol (HH and HV) Sentinel-1 C-band frequency (5.4 GHz) and PALSAR-2/SAOCOM L-band frequency (1.2 GHz) SAR images of the Gipps Ice Rise rift system on the Larsen C Ice Shelf during the 2020-2021 melt year. Rift geometry was characterized using the ATL06 land ice height product from ICESat-2, and surface melt was identified using a fixed threshold applied to Advanced Scatterometer (ASCAT) imagery. A Kolmogorov-Smirnov test was performed on ice type classes to determine their spectral separability in SAR images throughout the melt year. To further evaluate the performance of different SAR configurations on rift detection, pixel-based and image object-based Random Forest classifications were tested during late winter and late melt conditions. Overall, rifts that are filled with mélange are difficult to discriminate from the surrounding firn across seasons. Greater consistency in rift detection is found using L-band frequency compared to C-band, with enhanced L-band capability in winter in the presence of a thick ice mélange layer. In general, HV polarization provides greater separability between ice types compared to HH polarization and improves the detection of rifts through most of the melt year, apart from the late melt stage. Lastly, an object-based approach is superior to a pixel-based approach for the application of machine learning to automate rift detection using SAR. Optimizing the full potential of C- and L-band SAR for rift detection, and the development of an object-based machine learning detection method, will lay the groundwork for future automated rift detection and calving studies. Here a bottom-up assessment of SAR-based rift detection is presented, which provides a useful foundation for future algorithm development and the implementation of a standardized rift detection method.
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    Detection of coccolithophore bloom development in the Salish Sea, Canada: Leveraging reflectance data from autonomous shipborne in situ radiometers and Sentinel-3A with a random forest classifier
    (2025) Wang, Ziwei; Costa, Maycira
    Phytoplankton are the primary producers in the ocean, forming the base of the marine food web. Among them, coccolithophores hold particular significance due to their ability to form extensive blooms and their unique role in oceanic calcium and carbonate cycling, as well as related biogeochemical processes. Current limitations in using satellite imagery to derive accurate phytoplankton data, such as chlorophyll concentrations and phytoplankton functional types stem from insufficient in situ reflectance measurements to develop models and validate satellite reflectance. To address this, we deployed a suite of hyperspectral radiometers equipped with autonomous solar tracking capability, collectively known as SAS Solar Tracker (Satlantic Inc./Sea-Bird, denoted as SAS-ST hereafter), atop a commercial ferry traversing the Salish Sea, Canada. We specified the optimal geometry for SAS-ST installation, as well as the identification and flagging of unfavourable meteorological conditions, correction for sun glint and skylight contributions, mitigation of structural interferences, and subsequent application of bidirectional reflectance distribution function (BRDF) corrections to ensure optimal data quality. Assessment of the final data quality was conducted using a quality assurance method that considers spectral shape similarity, revealing that approximately 92% of the acquired reflectance data aligned well with the global database, indicating high quality. During the data collection period of this research in the summer of 2016, an unprecedented coccolithophore bloom occurred in the Salish Sea area. Coccolithophores, a distinctive phytoplankton species, are encased in calcium carbonate plates called coccoliths, which can be shed into the water during later stages of the blooms, significantly augmenting water reflectance. Based on its unique spectral features, our research successfully identified the presence of the coccolithophore bloom and further categorized the bloom spectra into growing and decaying stages. The hyperspectral reflectance SAS-ST data were initially convolved to the Sentinel-3A OLCI 10 spectral bands spanning 400 to 709 nm. Comparison of Sentinel-3A OLCI satellite spectra with SAS-ST in situ data revealed that reflectance acquired by the OLCI satellite was underestimated, particularly in the 400-443 nm range and the decaying bloom category. Consequently, we developed an adapted machine learning algorithm based on wavelengths ranging from 490 nm to 709 nm, which increased the overall prediction accuracy for OLCI-measured coccolithophore spectra from 0.794 to 0.891, and enhanced the Kappa coefficient from 0.14 to 0.60. By leveraging data from autonomous shipborne In situ SAS-ST and Sentinel-3A OLCI, my research overcomes current limitations of coccolithophore detection algorithms in coastal waters impacted by river plumes, while also providing new insights into coccolithophore dynamics and potentially enhancing their remote sensing.
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    Virtual reality (VR) storytelling: Building awareness and reducing stigma towards waste pickers
    (2025) Ebrahimi, Bita; Gutberlet, Jutta; Baniasadi, Amirali
    This thesis explores the potential of Virtual Reality (VR) storytelling as an innovative tool to challenge dominant narratives, build critical awareness, reduce stigma, and foster empathy towards marginalized and stigmatized communities. Grounded on decolonial and critical frameworks, and drawing on Paulo Freire’s problem-posing education and conscientization, the study investigates how Virtual Reality (VR) storytelling can bridge the gap between abstract understanding and emotional engagement, supporting social inclusion and knowledge democracy. This research chose to work with waste pickers’ community, who often experience marginalization, exclusion from policy decisions, and societal devaluation, despite their significant contributions to environmental sustainability. Through a participatory collaboration, with a waste pickers’ community in São Paulo, Brazil, the research integrates Virtual Reality (VR) Storytelling with Community-Based Research (CBR). Following official coordination and respective ethical procedures, visual data are collected, including 360-degree video footage capturing the work environment of the waste pickers and their personal narratives. This combination of qualitative data (interviews and visual documentation) forms the core of the primary data integrated into a VR simulation. The VR simulation created for this project allows users to experience the actual workplace of waste pickers and listen to their stories narrated by the waste pickers themselves in an intimate setting as if they were truly present in that environment. The final simulation has been showcased in three different venues in Canada. Impressively, audience feedback, both verbal and written, highlights that the developed method has a strong potential to contribute to critical education of people, by challenging preconceived notions, enhancing public awareness and fostering empathy among the participants. Finally, based on the integration of VR storytelling with community engagement, this thesis argues that immersive storytelling would help us go beyond traditional learning processes and serve as a powerful medium for mobilizing knowledge, building critical awareness, ultimately fostering a more equitable and inclusive society.
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    Exploring food waste in universities: A case study of the University of Victoria and the Jaramogi Oginga Odinga University of Science and Technology
    (2025) Wuntah, John; Gutberlet, Jutta
    This thesis explores the socio-cultural and systemic drivers of food waste among university students at the University of Victoria (UVic) in Canada and Jaramogi Oginga Odinga University of Science and Technology (JOOUST) in Kenya. Drawing on Social Practice Theory (SPT) and Political Ecology (PE) theoretical frameworks, the research investigates how cultural norms, institutional policies, and infrastructural factors contribute to food waste in these academic environments. Using a combination of focus groups, photo narratives, and semi-structured interviews with students, faculty, and food service personnel, the findings reveal that food waste is shaped by large portion sizes, dissatisfaction with taste, limited storage options, and social and cultural norms. At UVic, the rigid meal plan system promotes over-serving, while JOOUST’s pay-as-you-eat system, though seemingly fairer, carries the risk of over-purchasing, influenced by communal dining practices. The study emphasizes that addressing food waste in higher education institutions requires a holistic approach that goes beyond individual behaviors to consider the broader cultural and systemic factors at play. By recognizing the influence of both student practices and institutional constraints, this thesis highlights the need for targeted, context-specific interventions to foster sustainable food consumption and waste reduction on university campuses.
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    Housing insecurity and housing rights in times of financialization and global health emergency: Lessons from communities in Brazil
    (2025) Dias, Sharon Darling de Araújo; Rose-Redwood, Reuben Skye; Barbosa, Jorge Luis
    Communities across the world have been heavily impacted by two interconnected crises: a lack of adequate housing and the Covid-19 pandemic. As some of the primary measures to contain the spread of the coronavirus relied on proper hygiene procedures as well as physical and social isolation and lockdowns, those already in a precarious housing situation and under financial distress suffered during the Covid-19 pandemic in a singular manner needing to be further supported. My research investigates the interplay between precarious housing and the global pandemic in times of ongoing financialization of housing rights, and how this has affected low-income households in Brazil generally and low-income women, gender diverse people and racialized people in particular. To accomplish the goals of this study, I used a community-based participatory approach and partnered with local organizations and community leaders to study housing during the Covid-19 pandemic. Virtual data collection occurred between 2021 and early 2022 followed by in-person fieldwork in the second half of 2022. Additionally, I deployed a mixed-method approach using statistical survey at the country scale, and purposeful and snowball sampling techniques for qualitative data collection. I further analyzed the case of residents living in impoverished communities and in low-income, large-scale housing complexes in Brazil, focusing on Fortaleza Metro Region, the capital of Ceará state in northeast Brazil. As results, this research has found complex urban social dynamics in low-income communities in times of pandemic such as the challenges of living in inadequate housing, territorial disputes affecting residents’ everyday life, and chains of solidarity and mutual aid despite the general state of precarity. This study critically analyzes residents’ perspectives on precarious housing and housing development. Hence, a compilation of the respondents’ narratives and perceptions of their everyday life experience as marginalized groups in the context of Covid-19 have pointed to recommendations co-created by community partners and individual participants envisioning the improvement of housing development that target the most vulnerable, and for reviving a progressive housing policy in Brazil, which points to housing needs being addressed through community-based approaches to urban development rather than more mega-projects that build thousands of housing units in peripheral lands. This enables urban and housing development planning and actions that consider the experiences, shocks, knowledge and perspectives of vulnerable residents in post-pandemic times as well as the possibility to use the results for improving community development, pandemic preparedness and housing development for the poor.
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    "'Foreign villains and home-grown heroes': A critical geopolitical re-reading of a neoliberal text from The Atlantic Monthly"
    (2001) Lloyd, Andrea L.; Moss, Pamela; Lonergan, Stephen C.
    This study presents a critical analysis of neo-liberal discourses of international migration. Through a close reading of the text "Must it be the West against the Rest?", I challenge the authors' representation of refugee/migrants as a pre-eminent geopolitical threat to 'global order' in the post-Cold War period. I employ a critical geopolitical approach to problematise this identification of a 'new' antagonism not as an objective description of reality, but as part of powerful discursive representational practices that produce exclusion. I argue that these sorts of explanations are less about refugees/migrants and the 'reality' of international migration, and more about the need to secure Western hegemony and its idealised way of life. One means to resist the exclusions in neo-liberal texts is to resist the narrow conceptual categories that they force upon their readers, and to reject the exclusive 'we' that is created for 'us' in these texts.
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    Flushed away: How low and high magnitude turbidity currents affect the bathymetry, morphology and, sedimentation in the Nass Delta submarine channel
    (2025) Parkinson, Felix; Kwoll, Eva
    Turbidity currents, a type of sediment density flow, are one of the largest mechanisms of sediment transport in the ocean. They often incise submarine channels that can confine flows and allow them to runout long distances. However, these flow events are poorly understood as they are difficult to monitor directly, and therefore questions remain about how different magnitudes of flow move sediment while interacting with seafloor morphology. The aim of this study was to address some of these knowledge gaps by investigating sediment change in the Nass Delta submarine channel system, a region that had not previously been studied. Here, repeat bathymetric surveys from 2020, 2021, and 2023 were used to calculate bathymetric change to quantify erosion and deposition in the submarine channel system caused by turbidity currents. The results from the first bathymetric change interval (2020-2021) showed little net-change and instead sediment was ‘shuffled’ down system by turbidity currents. This was expressed as predominantly deposition at the head of the channel, an approximate balance of erosion and deposition throughout most of the length of the channel and minor deposition on the lobe. During the second interval (2021-2023), the channel was dominated by erosion, similar to ‘flushing’ flows observed in other channel systems, and the lobe complexes showed net deposition that was an order of magnitude higher than the previous interval. This was interpreted to represent three magnitudes of flows that were either dissipative with a short runout distance, in an auto-suspension state with balanced erosion and deposition, or in an ignition state. These flows resulted in substantial changes to in-channel morphology including aggradation up to 7 m/year and migration up to 70 m/year of crescentic bedforms, up-channel knickpoint migration up to 371 m/year, and the widening of channel bends by up to 45 m/year. Knickpoints were shown to influence the highest rates of erosion in both bathymetric survey intervals. However, only during the erosive, or ‘flushing’, interval were knickpoints created or removed. The ‘flushing’ interval also caused a channel avulsion which reactivated a distributary channel that had been previously blocked. Here, the term ‘thresholding flows’ is proposed to describe turbidity currents that change the channel equilibrium state. Although there were no direct measurements of turbidity currents, observations of river discharge, tidal predictions and mass wasting in the canyon indicate that the most likely triggers were either convective settling and remobilization of sediment on the delta or slope failures at the delta lip or canyon. Two facies of turbidite deposits were identified in sediment cores: Facies 1 sand beds, which were interpreted as deposits from higher magnitude flows with the Ta, Tb, Tc, and Td Bouma intervals and Facies 2 sand laminations, which were interpreted as deposits from smaller magnitude flows with Td and Te Bouma intervals. These deposits were dated by creating an age-depth model using excess 210Pb activity, 137Cs activity and 14C ages. This gave a return interval of 25 years for Facies 1 and 10 years for Facies 2 in the mid-channel reaches and 85 years for Facies 1 and 15 to 40 years for Facies 2 in the distal basin meaning that high- and low-density turbidity currents travel up to 22 km from the Nass Delta. These results show that the Nass Delta submarine channel system experiences frequent turbidity current activity that is comparable to other delta submarine channel systems such as the Squamish Delta and Bute Inlet systems, both over short (~1 year) and long (100s years) timescales, and therefore presents both an excellent study site for investigating turbidity current dynamics and poses a considerable hazard to seafloor infrastructure.
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    How communities thrive and foster sustainable livelihoods – An exploratory community-based research with Koforidua Zongo
    (2024) Zachari, Danae; Tremblay, Crystal
    In this thesis, I present an explorative community-based research with members of the Zongo community in the city of Koforidua, Ghana. Drawing on the community-based participatory research (CBPR) theoretical framework, including principles on co-production of knowledge and Indigenization of research, I use in-depth conversations and photo-narratives to explore, with participants, factors that enable individuals and their community to foster health, wellbeing, and sustainable livelihoods. The portrayal of Zongo communities in academic and grey literature has traditionally focused on socioenvironmental issues, thus creating a deficit-based, and incomplete, story of the dynamic lifeworlds and multiple worldviews within Koforidua Zongo (KZ). In contrast, participants’ insights highlight the community’s vibrancy, and its multidimensional sociopolitical, economic, and cultural wealth. The study amplifies participants' voices on the multiple, interconnected, positive factors fostering health and wellbeing at a personal, and community level. Participants’ insights show how shared language, belief system, values, and cultural practices stimulate social cohesion. In addition, they offer narratives of mutual aid and empowerment through examples of how the community operates and mobilizes to support one another. Drawing on what participants shared, I discuss how community members perceive health and wellbeing in a relational manner, in addition to how they understand thriving as a communal process, with the shared responsibility to build mutually supportive and beneficial relations for all.
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    Fire regime change in high-value temperate forested watersheds: a paleoecological investigation in the Greater Victoria Water Supply Area (GVWSA) on southern Vancouver Island, British Columbia
    (2024) Horrelt, Daniel Ross; Bone, Christopher; Brown, Kendrick
    Climate change is driving a global increase in wildfire that is disproportionately impacting temperate coniferous forests. These trends are forecast to continue with regional increases in area burned and extreme fire weather; however, the uncertainty associated with modelling the future extent and magnitude of change in complex fire systems remains a challenge for researchers. Examining historical fire regimes through paleoecological reconstructions of climate, vegetation, and fire can offer insights and can help validate models of future fire environments by characterizing potential analogues in the past. This study investigates the susceptibility of northern coastal temperate forests on Vancouver Island, Canada, to both past and future wildfire disturbance. Sediment cores were extracted from three lakes along a regional east-west precipitation gradient within a high-value forested water supply area. Supplemental data from a previously cored fourth lake within the water supply were also analysed. A comparison between warm-dry early- and cool-moist late-Holocene intervals was used to delineate spatio-temporal changes in fire regime. The results indicate that precipitation was lower in the past, with more open forests that were dominated by invaders and resisters – two important fire-related plant functional types. The wettest, western-most site experienced the greatest change and had frequent fires in the early-Holocene. This highlights the extent of fire regime shift and suggests that forests currently less predisposed to fire may become vulnerable in the future, the implications of which concern fire probability simulations and management actions to reduce wildfire risk to water supply.
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    Spatiotemporal distribution, abundance, and persistence of kelp forests in the Broughton Archipelago, British Columbia, Canada
    (2024) Man, Long Ching; Costa, Maycira
    Kelp forests are highly productive coastal ecosystems on 25% of the world’s coastlines, providing key biogenic habitats in nearshore ecosystems. These ecosystems are experiencing variable changes worldwide, ranging from detrimental impacts from climate change and pollution to trophic collapses. Still, in British Columbia (BC), Canada, the kelp distribution and drivers of kelp change remain largely unknown in many locations. Thus, local-scale studies are needed to understand kelp dynamics to inform marine spatial planning decisions for coastal practitioners. In particular, the Broughton Archipelago, BC, located in Kwakwakaʼwakw territories, supports floating kelp forests of various species compositions and sizes in a spatially explicit environmental gradient across an outer archipelago subregion and an inner fjord subregion. The Mamalilikulla First Nation, ‘'Na̱mg̱is First Nation, and the Kwikwasut’inuxw/Haxwa’mis First Nation, who formed the Broughton Aquaculture Transition Initiative (BATI), are interested in the status and trends of kelp forests due to their utility as juvenile salmon habitat. This research investigates kelp forests' spatiotemporal distribution, abundance, and persistence in the Broughton Archipelago. We first identify environmental and biotic variables that drive spatial differences in kelp forest distribution and abundance. We achieved this by mapping floating kelp abundance (giant kelp: Macrocystis pyrifera, bull kelp: Nereocystis luetkeana) at 31 focal sites across the environmental gradient using unmanned aerial vehicle and high-resolution satellite imagery, compiling environmental data from in-situ sources and environmental models, and characterizing grazer (sea urchins, Strongylocentrus spp. and Mesocentrotus franciscanus) and predator (sunflower sea stars, Pycnopodia helianthoides) abundances from remotely operated vehicle footage. Second, we investigate the spatiotemporal persistence and resilience of kelp forests in the face of climate change. This was achieved by creating long-term (1984 to 2023) and short-term (2016 to 2023) time series of floating kelp areas in association with environmental drivers of change using medium- (30 m) to high- (3 m) resolution satellite imagery, and spatially combining yearly kelp areas to identify spatial patterns of kelp persistence. Overall, we found that the lower sea-surface temperatures, flatter bottom slopes, and higher tidal current speeds typical of the archipelago subregion were positively associated with kelp abundance; whereas the warmer sea-surface temperatures, steeper bottom slopes, and lower tidal current speeds found in the fjord subregion were negatively associated with kelp abundance, reinforcing the known spatial patterns of kelp distribution and abundance found in other studies across the BC coast. Biotically, sea urchin and Pycnopodia abundances did not significantly affect kelp abundance, likely due to low abundances of sea urchins. Kelp forests were temporally persistent, with most kelp areas displaying increases or no change in kelp areas, and kelps were more persistent in their centers than the edges of each kelp bed. These findings provide a baseline understanding of kelp distribution, abundance, persistence, and their associated environmental and biotic drivers in the Broughton Archipelago. Ultimately, this can inform kelp forest conservation and management decisions such as kelp harvesting and kelp restoration for by local communities and First Nations, and contribute to a broader regional understanding of the spatiotemporal patterns of kelp forests in the Northeast Pacific Ocean.
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    Using acoustics to explore fin whale (Balaenoptera physalus velifera) ecology and habitat in British Columbia
    (2024) Rannankari, Lynn; Duffus, David Allan; Burnham, Rianna E.
    Globally, fin whales (Balaenoptera physalus) were heavily targeted by commercial whaling. Despite this, some populations are recovering; their numbers are increasing in the Southern Hemisphere and North Atlantic. Fin whales are listed as vulnerable on the International Union for Conservation of Nature (IUCN), although populations worldwide show varying degrees of recovery. Fin whales were once the most abundant large cetacean species off the coast of British Columbia (BC). They are currently listed under Canada’s Species at Risk Act (SARA) as Threatened, although their status is currently in consideration for downlisting following recommendations by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) in 2019. Although fin whales may be returning to coastal areas in BC, efforts to track their recovery in their core habitat, in deeper waters and off the shelf break, has been limited. Much of what is known about their habitat use, ecology and seasonal movements come from details from historical catch records, with recent designated studies looking to refine this knowledge. In this thesis, I consider the potential recovery of fin whales and use acoustic recordings from two study sites in BC waters to analyze their vocalizations. If populations are recovering in BC, recording and analyzing their acoustic behaviour as they rebuild their social and physical connectivity can provide clues to how they are responding after decades of removals. Primarily driven by the considerable number of fin whale vocalizations observed in the acoustic recordings, I create a comparative analysis of fin whale call types to provide finer resolution to the spatial and temporal distributions of vocalizations. The presence of 20 Hz and 40 Hz call types, associated with breeding and foraging behaviour, respectively, were analyzed to determine fin whale habitat use. This comparison analysis indicated fin whales use coastal and offshore areas very differently; considerably higher call presence of both types was observed offshore, and song patterning was only present here. The diverse range of call parameters observed within the 40 Hz call type, particularly from the offshore study location, led to further analysis for the potential for sub-division within this call type. Cluster analysis indicates the structure of 40 Hz call types is more varied than previously recognized and determines five subcategories within the 40 Hz type based on call features. I further explore the potential of subcategories within this call type by analyzing the relative presence of fin whale 40 Hz calls over daily, monthly and seasonal time periods to better understand drivers of the variability. Fin whale song patterns in the offshore acoustic recordings at Clayoquot Slope suggest BC waters are used for courtship, breeding and calving. The difference in song structures may suggest at least two populations using these waters. Although the dominant song pattern structure matched previous findings for the west coast of North America, considerable change in pattern timing was evident. Additionally, new song patterns not previously described for this region were found. Overall, knowledge on whale acoustic use and the value of acoustics to their ecology is still over-simplified, but our understanding increases with deeper study. Some of my observations and understanding of various fin whale acoustic signals have yet to be described in the current literature. Fin whales have a more complicated acoustic repertoire than previously thought and the variety of calls observed indicates BC is an important habitat for recovering populations.
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    Forest stand hydrological recovery of snow accumulation and ablation investigated using simultaneous localization and mapping (SLAM) enabled LiDAR
    (2024) Potter, Cydne Rae; Peters, Daniel Lee; Niemann, Olaf
    Forest-snow interactions were analyzed using fine-resolution mobile terrestrial LiDAR in four stands representing increasing forest maturity ranging from a recently replanted clearcut to a mature forest in the interior cedar – hemlock biogeoclimatic zone of the southern Selkirk Mountain range in British Columbia, Canada. LiDAR-derived models representing peak snow depth and daily ablation were used to assess the impact of sampling intensity on stand-level averages and to determine sampling distances required to capture between-stand differences and within-stand variability. The process of hydrological recovery, a term which describes the return of snow accumulation and ablation processes in regenerating forests to pre-disturbance conditions, was investigated at the scale of individual trees and for the full stand. Outcomes from this study better quantify the influence of tree growth on peak SWE and ablation rate at both the tree and stand level for north aspect mixed conifer stands. The process of negative ablation recovery in early juvenile stands reported in previous studies is herein clearly observed. The methods used increase transferability of outcomes to stands where canopy characteristics (i.e., height, crown cover, and heterogeneity) differ from the reference sites considered here.
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    Human recreation in protected areas impacts spatial dynamics and risk-resource trade-offs among a wildlife community
    (2024) Harbo, Victoria; Bone, Christopher
    Large mammals play critical roles in maintaining ecosystem balance, but their need for expansive, undisturbed habitat makes them particularly vulnerable to human activities. Protected areas are designed to conserve biodiversity by providing refuges for wildlife. However, within these areas, large mammals remain at risk from disturbances due to the growing trend of non-consumptive outdoor recreation. Understanding the effects of human presence on mammal communities and large carnivores like cougars (Puma concolor) is essential for informing effective land and wildlife management. This thesis addresses this need by examining how human presence affects cougars’ risk-resource trade-offs, and then broadening the scope to assess human impacts on a community of large mammals. Data were collected from an array of 48 camera traps across the public-access Sooke Hills Wilderness Area Park (SHWA) and the restricted-access Greater Victoria Water Supply Area (GVWSA) on southern Vancouver Island. In Chapter 2, cougar occurrence was evaluated through competing hypotheses related to habitat, prey, and anthropogenic risk. These results were used to predict cougar occurrence across a network of roads and trails within the study area. Cougar occurrence was best explained by habitat and risk at a 750-meter buffer, where cougars avoided human presence but were more willing to tolerate this risk when their preferred habitat was available in the same area. In Chapter 3, I assessed how a community of large mammals, including Columbian black-tailed deer (Odocoileus hemionus columbianus), Roosevelt elk (Cervus canadensis roosevelti), cougar (Puma concolor), black bear (Ursus americanus), and grey wolf (Canis lupus) responded to landscape heterogeneity, heterospecifics’ detection frequency, and land-use restrictions. Differences in community composition between the SHWA and GVWSA revealed that all wildlife species avoided public-access sites, with a clear difference in community composition due to access restrictions. Carnivore species overlapped spatially, suggesting reduced spatial partitioning due to human activity. This thesis shows that site-level human activity can alter risk-resource trade-offs for large carnivores, which can scale upwards to shift species distributions. Given the vulnerability of large mammals to disturbance, it is crucial to consider the impacts of non-consumptive activities on both apex predators and entire wildlife communities.
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    Sharing the catch; Social and environmental correlates of body condition in threatened Northern Resident killer whales
    (2024) Kay, Sharon; Darimont, Chris T.
    Effective conservation and management should consider a species’ social dynamics, given that resource scarcity can lead to intragroup conflict. When food is limited, the reallocation of shared resources may incur costs for group members who depend on provisioning or for members that provide shared food. Resident Killer Whales share prey within their stable kin-based groups (matrilines), but little is known about how social group composition might influence allocation of shared prey and associated individual physiological condition. Using drones, we collected aerial images to estimate body condition of Northern Resident Killer Whales over ten years (2014-2023) to evaluate the health of individuals, some across multiple years (n = 175 individuals from 39 matrilines), in a population of approximately 345 whales. Our first objective was to examine the association between individual body condition and the composition of their matrilines, while accounting for salmon availability. Our second objective was to evaluate if mothers with more offspring had lower body condition, and if this relationship depended on their offspring sex. Using two candidate model sets of generalized mixed effect models, we found that social variables influenced body condition. Specifically, males showed declines in body condition as the proportion of juveniles in the matriline increased, while females either showed no change or increased in condition. These sex-specific patterns suggest that males may receive reduced investment through prey sharing in families with more dependent young. Additionally, we found a negative relationship between the body condition of adult females and the number of offspring they have, indicating that adult females may also incur costs in provisioning offspring. Interestingly, these patterns did not depend on salmon abundance. Our results demonstrate how sociality can influence individual health and provides insights into intragroup conflict and parental investment in a species with lifelong parental care and high social stability.
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    Social influence on vessel behaviour around cetaceans in the waters of Northeast Vancouver Island
    (2024) Gladwell, Alison; Darimont, Chris T.
    When managing human behaviour around wildlife, regulations are often designed to mitigate disturbance to vulnerable species. Yet, patterns and drivers of compliance with such regulations are poorly understood. In partnership with the Marine Education and Research Society, we assessed local compliance rates and examined patterns underlying vessel-whale encounters by observing vessel behaviours around marine mammals. In the summers of 2022 and 2023 (n = 475 observation hours, 902 interactions between marine mammals and boats), we assessed motorized vessel compliance to Canada’s Marine Mammal Regulations and examined a suite of boater behaviours relating to humpback (Megaptera novaeangliae) and killer whales (Orcinus orca) in Northeast Vancouver Island. Recreational and ecotour vessels had similar rates of compliance (85 and 87%, respectively), with the lowest compliance rates around killer whales (74%). Complementary modelling showed that closer distances between vessels and whales were associated with vessels that spent more time with an animal or that were idle. In contrast, greater distances from the whales were associated with interactions involving a higher number of vessels. Assessing other measures of potential disturbance, we found that the number of vessels surrounding an animal varied by study site and was higher in encounters after VHF radio communication about the focal whale compared to encounters without mention. Finally, the time a vessel spent with a whale was higher for vessels at idle and slow/medium speeds compared to vessels travelling at faster speeds. Results from this work can inform geographic and practical areas of focus for education, enforcement and policy development.
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    Insights into cetacean habitat use in British Columbia using visual and acoustic methods
    (2024) DeMeyer, Roanan; Duffus, David Allan; Burnham, Rianna E.
    Cetaceans play critical roles in marine ecosystems as top predators and ecosystem engineers. In British Columbia (BC), cetacean populations are recovering from industrial whaling and responding to other anthropogenic pressures, such as vessel noise, climate change, and ship strikes. Protecting these populations requires knowledge of their habitat use patterns to inform effective management. In this thesis, I use visual and acoustic methods to contribute to the historical and current knowledge of cetacean habitat use in BC’s waters. In Chapter 2, I use visual data gathered via transect line surveys offshore of Clayoquot Sound, BC, between 1993 and 2007. These surveys yielded observations of eleven cetacean species. Analyses of habitat variables indicated significant interspecific differences in habitat use, a negative correlation between Dall’s porpoise group size and sea-surface temperature, and an increased offshore distance for the southward gray whale migration. Interannual changes in sighting rates reflected known population dynamics, while seasonal changes supported inshore-offshore movement patterns for Dall’s porpoise and Pacific white-sided dolphins. In Chapter 3, I use acoustic data gathered from two hydrophones deployed on the east and west coasts of Haida Gwaii in Gwaii Haanas National Park Reserve, National Marine Conservation Area Reserve, and Haida Heritage Site from August 2018 to August 2019. Manual analyses of these data were used to identify cetacean call and vessel presence. At least eight species were identified and foraging, breeding, and migratory habitat uses were inferred from call timing and behavioural associations of call types. The maximum frequencies of the loudest identified vessel noise were measured and overlap with cetacean call frequencies, as well as the co-occurrence of cetacean calls and vessels, suggest the potential for call masking and disturbance. Large and small vessels were more common on the west and east coasts, respectively, and these findings inform site-specific noise management recommendations. In Chapter 4, I use these acoustic data to provide insights into the gray whale migration route and habitat use, since these are poorly understood in northern BC. Gray whales were only detected during the northward migration on the east coast, suggesting that the migrations primarily occurred outside the hydrophone detection ranges. The visual and acoustic monitoring conducted in this thesis contributes to cetacean conservation by advancing our understanding of cetacean habitat use and vessel presence in BC.
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    Spatial patterns of osteoporosis in British Columbia (1985-1989) : possible links with sediment geochemistry, lake and drinking water quality
    (1994) Zhang, Liping
    This geographical study initially seeks to establish spatial patterns of osteoporosis in British Columbia for the period 1985 to 1989. In addition, in an attempt to broaden understanding of the etiology of this disorder, it examines possible relationships between the Hospital Diagnosed Osteoporosis Rates (HDOR) and environmental factors such as sediment geochemistry and lake and drinking water quality. The data used in this study were obtained from a wide variety of sources, including the BC Ministry of Health and Ministry Responsible for Seniors, BC Ministry of Environment, Lands and Parks, and the BC Ministry of Finance. Data were obtained also from numerous environmental managers who had collected water quality information for a diversity of reasons. In addition, a data bank compiled by Ian Norie and Harold D. Foster for use in an earlier study of digestive cancer and water quality also was utilized. Unfortunately, difficulties with quality restricted suitable medical data to the period 1985 to 1989. For each year and for the entire period as a whole, the data were used to calculate age standardized hospital diagnosed osteoporosis rates (ASHDORs) and standardized hospital diagnosed osteoporosis ratios (SHDORs). The former were calculated twice using two slightly different methods to remove duplicate cases. Since it was impossible to distinguish new cases (first diagnosed during the period 1985 to 1989) from hospital re-admissions of patients diagnosed as having osteoporosis in 1984 or earlier, the true incidence of the disorder in British Columbia could not be calculated (either as a rate or as a ratio). For this reason the term Hospital Diagnosed Osteoporosis Rate (HDOR), derived from analysis of hospital data, is used throughout this thesis. To identify the significance of the spatial patterns and possible links with the environment, two types of statistical methods of analysis were employed in this study, namely the Chi-Square test (x2) and Pearson correlation. One major conclusion that can be drawn from the results obtained in this study is that during the period 1985-1989, the Standardized Hospital Diagnosed Osteoporosis Ratio (SHDOR) in British Columbia varied spatially in a statistically significant manner in both genders (Figures 4.1-4.3). The analyses also clearly demonstrated that in British Columbia, osteoporosis occurred more frequently in women than men with a female to male ratio of 5.46:1. "ASHDOR" also increased markedly with age, particularly in those older than 45. Although several elements, including calcium, zinc, copper, lead and fluoride have been discussed in the medical literature as having possible roles in the etiology of osteoporosis, the current study was unable to identify any consistent statistically significant relationships between exposure to these elements in sediments, lake or drinking water and the "ASHDORs". In contrast, dissolved aluminum (Al_D) in drinking water repeatedly demonstrated statistically strong positive correlations with "ASHDORs" in both genders and in the population as a whole. The geographical evidence from British Columbia, therefore, tends to suggest that osteoporosis may be related to elevated dissolved aluminum levels in drinking water. Statistical abberations can produce spurious relationships between disease distributions and the physical environment, which may tend to suggest causal links where none exist. This may, or may not, be the case with osteoporosis and aluminum. Ideally this possible relationship should be tested using the Bradford Hill criteria, which are commonly employed to establish cause and effect. As yet, insufficient research on the topic makes this impossible. Therefore, the best that can be suggested is that the role of aluminum (particularly dissolved aluminum in drinking water) in the etiology of osteoporosis, should be given greater emphasis in future osteoporosis research.
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    Mapping coastal habitats using an imaging spectrometer
    (1993) Zacharias, Mark
    Airborne multispectral scanner imagery was acquired on Vancouver Island, British Columbia using an eight channel handset configured for intertidal remote sensing. Radiance plots, between band correlations and a principle components analysis were used in the examination of two physically and biologically distinct littoral regions. Five of the eight bands were found to contribute significant unique information pertaining to intertidal vegetation and substrate identification. Classification of the resulting five bands demonstrated that different substrates and algal genera could be identified, including the differentiation of spectrally similar Chlorophytes (green algae).
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    Monitoring spatial and temporal patterns structuring eelgrass (Zostera marina L.) fish diversity in Clayoquot Sound
    (2003) Yakimishyn, Jennifer Lee-Ann
    The linking of temporal variability in biodiversity with spatial scale is an integral component of marine conservation. In this study, I evaluated the interplay between the temporal variability in fish communities and local-to-regional environmental properties measured for eelgrass beds (Zostera marina) found in southern Clayoquot Sound, British Columbia. Effective monitoring of the temporal variability in eelgrass fish diversity required: 1) triplicate beach seine sets on a rising low tide, 2) sampling in early spring, early summer and late summer, and 3) diel sampling. The analysis of eelgrass fish data required alpha diversity measures (e.g. species richness and taxonomic distinctness), beta diversity measures ( e.g. taxonomic similarity), and multivariate methods to detect subtle temporal and between-site differences. Additional temporal changes in eelgrass fish diversity were evaluated in response to changes in local eelgrass bed properties and to regional changes in hydrodynamic energy. I found, in late spring, fish diversity differed between sites but these differences were not explained by eelgrass properties or hydrodynamic energy. However, in late summer, fish diversity appeared to be related to regional hydrodynamic energy but the explanatory power of local environmental and eelgrass variables was not high. Further research addressing additional abiotic variables and the influence of biotic processes is recommended.