The purpose of this study was to examine the habitat preference (or use), distribution and growth of darters (Channel Darter Percina copelandi, Logperch Percina caprodes, Fantail Darter Etheostoma flabellare, Tessellated Darter Etheostoma olmstedi and Johnny Darter Etheostoma nigrum) in tributaries of the Ottawa River, Québec, Canada. The Channel Darter’s habitat can be characterised by coarse heterogeneous substrate with water velocities greater than 0.25 m/s in zones with low bank slopes. Its distribution is limited to five tributaries of the Ottawa River, downstream from the first physical barrier. The Logperch and Fantail Darter’s habitats were similar to that of the Channel Darter, although the Fantail Darter was present in shallower waters. The Tessellated Darter was spatially partitioned from the others; the species seems to be a habitat generalist. The Johnny Darter was the least abundant darter and seems to prefer coarse heterogeneous substrate. The majority of growth in length was attained during the first year in all species. Growth rates were affected by the presence of parasites in the Channel Darter and Fantail Darter, non-parasitized individuals growing faster than parasitized individuals. Growth rates also differed among males and females in the Channel Darter, males growing faster than females.

Climate is a long-term driver of ecological change, but the rapidity with which climate is projected to change over the next century may push the limitations of ecological adaptability, to the detriment of biodiversity. Given their typically small populations, limiting biological traits and exposure to external stressors, species currently classified as “at risk” may be among the most vulnerable to climate change and least capable of adapting naturally. A screening level assessment of the impacts of climate change on endangered species in Canada was conducted by integrating knowledge of the current status and characteristics of each endangered species with projections of climate change and climate change impacts. It was determined that climate change may have a potential overall negative influence on more than half of all endangered species in Canada. However, while relatively few species were predicted to respond in an overall positive or neutral manner to climate change, a large portion of endangered species were classified as having insufficient information to generate a decision on the net influence of climate change; in many cases, these species were located at the northern extent of their range in warmer regions of Canada and have the potential to experience at least some benefits under climate change provided that other stressors are sufficiently mitigated. These results, as well as the inherent vulnerability of species at risk to environmental change, the potential for species at risk distributional shifts and the likelihood of increasing rates of species imperilment, demonstrate the need for greater consideration of the implications of climate change in species at risk management and policy. Canada’s Species at Risk Act (SARA) does not explicitly address the issue of climate change and limitations exist in SARA’s time-sensitive definition of wildlife species eligible for protection in Canada and in the interpretation of SARA’s mandates in the context of anthropogenically driven climate change. It is recommended that climate change be systematically considered in all species at risk assessments, recovery strategies and management plans and that SARA’s definition of a wildlife species be revaluated in light of shifting species distributions under climate change. Further recommendations to identify “values” that will assist in prioritizing species for conservation, to reassess the concept of an invasive species under climate change and to implement strategies that focus more broadly on the conservation of biodiversity and ecological integrity rather than individual species may require ethically complex discussions and decisions on the part of species at risk managers and policy makers. Future research should focus on informing species at risk management and policy by improving modeling capabilities at the species level, conducting in-depth analyses of priority species, and building knowledge of alternative species conservation strategies such as assisted colonization.

Climate is a long-term driver of ecological change, but the rapidity with which climate is projected to change over the next century may push the limitations of ecological adaptability, to the detriment of biodiversity. Given their typically small populations, limiting biological traits and exposure to external stressors, species currently classified as “at risk” may be among the most vulnerable to climate change and least capable of adapting naturally. A screening level assessment of the impacts of climate change on endangered species in Canada was conducted by integrating knowledge of the current status and characteristics of each endangered species with projections of climate change and climate change impacts. It was determined that climate change may have a potential overall negative influence on more than half of all endangered species in Canada. However, while relatively few species were predicted to respond in an overall positive or neutral manner to climate change, a large portion of endangered species were classified as having insufficient information to generate a decision on the net influence of climate change; in many cases, these species were located at the northern extent of their range in warmer regions of Canada and have the potential to experience at least some benefits under climate change provided that other stressors are sufficiently mitigated. These results, as well as the inherent vulnerability of species at risk to environmental change, the potential for species at risk distributional shifts and the likelihood of increasing rates of species imperilment, demonstrate the need for greater consideration of the implications of climate change in species at risk management and policy. Canada’s Species at Risk Act (SARA) does not explicitly address the issue of climate change and limitations exist in SARA’s time-sensitive definition of wildlife species eligible for protection in Canada and in the interpretation of SARA’s mandates in the context of anthropogenically driven climate change. It is recommended that climate change be systematically considered in all species at risk assessments, recovery strategies and management plans and that SARA’s definition of a wildlife species be revaluated in light of shifting species distributions under climate change. Further recommendations to identify “values” that will assist in prioritizing species for conservation, to reassess the concept of an invasive species under climate change and to implement strategies that focus more broadly on the conservation of biodiversity and ecological integrity rather than individual species may require ethically complex discussions and decisions on the part of species at risk managers and policy makers. Future research should focus on informing species at risk management and policy by improving modeling capabilities at the species level, conducting in-depth analyses of priority species, and building knowledge of alternative species conservation strategies such as assisted colonization.

Protecting existing habitat for species-at-risk is an important conservation measure; however, many populations occupy highly fragmented habitat patches to the extent that population persistence is unlikely without the creation of new habitat patches. This research examines the potential for clusters of rehabilitated aggregate extraction sites to be used as reintroduction sites for species-at-risk. Using a method combining GIS and metapopulation modeling, I evaluated the success of establishing metapopulations of the Five-Lined Skink, Eumeces fasciatus, in 137 clusters of aggregate extraction sites using three hypothetical recovery scenarios. Patch abundance and patch clustering had a significant negative effect on metapopulation extinction risk. Increasing the quality of a single patch relative to other patches of suitable quality had little effect on extinction risk and patch occupancy. Introducing all individuals into a single patch decreased extinction risk and patch occupancy. Rehabilitated aggregate sites could play a role in the protection of species-at-risk in Ontario.

I investigated whether Neogobius melanostomus, an invader of biodiversity “hot-spots” in Ontario facilitates or inhibits unionid mussel recruitment by serving as a host or as a sink for their parasitic larvae (glochidia). Infestation and metamorphosis rates of four mussel Species at Risk (Epioblasma torulosa rangiana, Epioblasma triquetra, Lampsilis fasciola, and Villosa iris) and one common species (Actinonaias ligamentina) on N. melanostomus were compared to rates on known hosts in the laboratory. All species successfully infested N. melanostomus, but only E. triquetra, V. iris, and A. ligamentina successfully metamorphosed, albeit at low rates. Neogobius melanostomus collected from areas of unionid occurrence in the Grand and Sydenham rivers exhibited body burdens of 39.4% and 5.1%, respectively. Analyses indicate that N. melanostomus serves more as a sink for glochidia than as a host for unionids, thereby limiting recruitment, which is a novel way by which N. melanostomus is affecting native mussel species.

Our planet is currently in the midst of a mass extinction event. Plants and animals are dying off at a rate undocumented since the dinosaurs went extinct 65 million years ago. Unlike earlier extinction events, however, the current ecological crisis is primarily being driven by a single species – homo sapiens. Although a seemingly overwhelming issue, environmental non-governmental organizations (ENGOs) have dedicated themselves to ensuring strong species protection. In Canada, these interest groups launched and sustained a successful national campaign for federal endangered species legislation that culminated in the enactment of the Species at Risk Act (SARA). While ENGOs‟ campaign for protective legislation has been well-documented by scholars, there is a dearth of research regarding ENGOs‟ strategies following the passage of SARA. In order to address this knowledge gap, this thesis examines and compares the strategies employed by interest groups in both the pre- and post-passage stages of the Act. After conducting qualitative interviews with seven representatives of Canadian-based ENGOs, this study finds that following the passage of SARA interest groups, dissatisfied with the government‟s weak implementation of the Act, decided to overhaul their strategic approach and shifted the species at risk issue to three new institutional venues: the boardrooms of private corporations, the Commission for Environmental Cooperation (CEC), and the domestic judicial arena. The thesis concludes that, despite inherent challenges, shifting institutional venues can be a successful strategy for ENGOs faced with a government reluctant to implement the hard-won legislative commitments. This work may prove to be particularly pertinent for other non-governmental organizations facing similar obstacles. / Graduate

The eastern massasauga rattlesnake, or massasauga, is threatened in Ontario. Massasaugas overwinter in habitat that is sufficiently moist, above the water table, and below the zero-degree isotherm in a physical space conceptualized as a resilience zone. A development project in the Eastern Georgian Bay subpopulation of massasaugas overwintering habitat necessitated restoration. The Toronto Zoo hibernacula design was deemed inappropriate for use in this bedrock dominated landscape, as the limited deep groundwater percolation would result in flooding of the habitat from the fall to spring. Massasaugas in EGB, overwinter above the water table in Sphagnum peat hummocks. The ecohydrological factors of these hummocks in confirmed massasauga habitat were evaluated in a mixed effect linear model. It was found that taller hummocks, taller shrubs, and less WT variability were the best predictor of suitable conditions. This information was combined into a restoration method that moves surficial peat material from a soon to be impacted wetlands to an adjacent depression with mean depths of 40-80 cm, with mean bottom substrates 15-30 cm, and varying proportions of open water and floating peat with different vegetation communities. This design limits water table variability and allows for the growth of tall shrubs. Unforeseen circumstances meant that peat to be used in the project had to be stockpiled, which increased peat bulk density and limited photosynthesis. Despite this, restored habitat had similar mean lengths of unsuitable conditions compared to confirmed massasauga wetland habitat. The physical size of available overwintering habitat, as well as the total duration of unsuitable conditions, was not significantly different between restored wetlands, unconfirmed wetlands, and confirmed wetlands. Amendments to increase the cover of live Sphagnum moss will likely increase the duration and size of suitable conditions in the restored wetlands. Based on this success with degraded materials this new method of restoration design shows great promise in this region. / Thesis / Master of Science (MSc)

Woodland caribou population declines in west-central Alberta precipitated a wolfcontrol. This program to protect caribou could be compromised if (1) there are strong public pressures against helicopter gunning and strychnine poisoning of wolves and/or (2) other predators compensate to kill caribou. Because bears can be important ungulate predators, I used stable isotope techniques to reconstruct black and grizzly bear diets including contributions of caribou, caribou calves, ants, ungulates (moose, deer and elk), and 3 plant groups. Bears assimilated 2-58% terrestrial protein indicating large variation among individuals. As an alternative to current wolf-control practices, I reviewed spatial and temporal patterns of harvests (1985-2006) on registered traplines. Wolf trapping has increased during the past 2 decades, but on average trappers harvested only 10% of the provincial wolf population, well below culls required to control the population. Under the registered trapline system it is unlikely that trapping could control wolf abundance. / Ecology

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