No description available.

Little is known about the distribution and habitat suitability of yellow rails (Coturnicops noveboracensis) throughout their breeding range. Yellow rail and vegetation surveys were conducted at 80 wetlands in south-central Manitoba in 2010-2011 to evaluate the effectiveness of repeat-visit, call-broadcast night surveys for detecting this species and habitat associations of this species at the 3-km landscape, patch, and plot scales. Yellow rails were detected at 44% of the study wetlands. Yellow rail detection was imperfect (0.63 in each year), but call-broadcast increased the number of yellow rails detected. Future yellow rail survey efforts should employ call-broadcast and at least three surveys per survey point. Yellow rail presence was positively influenced by the amount of marsh/fen in the landscape and the proportion of rushes at the study wetlands. These characteristics should be considered when identifying potential yellow rail habitat in south-central Manitoba.

Little is known about the distribution and habitat suitability of yellow rails (Coturnicops noveboracensis) throughout their breeding range. Yellow rail and vegetation surveys were conducted at 80 wetlands in south-central Manitoba in 2010-2011 to evaluate the effectiveness of repeat-visit, call-broadcast night surveys for detecting this species and habitat associations of this species at the 3-km landscape, patch, and plot scales. Yellow rails were detected at 44% of the study wetlands. Yellow rail detection was imperfect (0.63 in each year), but call-broadcast increased the number of yellow rails detected. Future yellow rail survey efforts should employ call-broadcast and at least three surveys per survey point. Yellow rail presence was positively influenced by the amount of marsh/fen in the landscape and the proportion of rushes at the study wetlands. These characteristics should be considered when identifying potential yellow rail habitat in south-central Manitoba.

Temperate grasslands and the biodiversity they sustain are becoming increasingly imperilled. Habitat loss and degradation are considered primary causes of grassland species declines. Since livestock production is a dominant use of remaining temperate grassland, livestock producers and the grazing management decisions they make play a vital role in the recovery of grassland species. In this thesis, I examined social and ecological factors that drive habitat management and abundance of prairie wildlife species so as to contribute to conservation planning for prairie species at risk and their habitat. I focused on grassland songbirds because, of all prairie wildlife species, grassland birds have undergone some of the most dramatic declines in recent years. I employed an interdisciplinary approach, using theory and methodology from ornithology, rangeland management and the human dimension of conservation biology to achieve three objectives: i) to determine the extent to which indices of rangeland health explained variation in grassland songbird abundance for ten grassland bird species, including three species currently listed under Canada’s Species at Risk Act: Sprague’s pipit, McCown’s longspur and Chestnut-collared longspur; ii) to describe livestock producer characteristics, summarize producer awareness of and attitudes towards species at risk and the Canadian Species at Risk Act and evaluate how characteristics, awareness and attitudes affect producer willingness to engage in voluntary stewardship actions that support species at risk conservation; and iii) to explore relationships between select social and ecological factors and bird abundance for the three aforementioned grassland bird species at risk to elucidate novel pathways for achieving their conservation. I address the first objective in Chapter 2, where I identify the rangeland health index as a poor predictor of bird abundance and vegetation structure variables, such as litter and vegetation volume, as strong predictors of bird abundance. These findings make a case for further refining the rangeland health index as a tool for biodiversity assessment. In Chapter 3 I achieve the second objective and summarize producer characteristics, awareness and attitudes towards species. I also identify awareness, attitudes and rangeland management learning approach as important to producer willingness to support species at risk recovery. I accomplish the third objective in Chapter 4, where I present results of a structural equation model that upholds bird-habitat relationships identified in Chapter 2 and distinguishes management jurisdiction, size of land holdings and attitudes as important social factors to consider in conservation planning. Chapters 2 and 3 contribute to theory and methodology related to the ecological and social dimensions of grassland bird conservation, respectively. Chapter 4 demonstrates how structural equation models can be used to integrate social and ecological factors, and thereby inform habitat conservation and management. Both social and ecological data presented in this thesis make valuable contributions to producer engagement and habitat management aspects of conservation planning efforts for species at risk in the Milk River watershed of southwestern Saskatchewan. Overall, my findings point to the importance of a joint effort by regional private and public managers to use livestock grazing to create a mosaic of vegetation structure and habitat conditions suitable for the grassland bird community as a whole. This thesis provides a methodological approach that draws on and integrates social and ecological data, methods and concepts, thereby demonstrating how to conduct interdisciplinary research for biological conservation.

The U.S. Endangered Species Act (U.S. ESA) is one of the oldest pieces of legislation to protect endangered species. The bodies responsible for administering the U.S. ESA have published species Biennial Recovery Statuses (BRSs) in Reports to Congress on the Status of Endangered and Threatened Species. We found that expert assessments of species recovery trends match BRSs reasonably well; however, there appears to be a weak relationship between the BRSs and available data tracking species abundance and range trends. We aimed to establish whether the recovery trends of species examined were detectably associated with their threats, the general U.S. ESA tools, or recovery actions. We found positive associations between species recovery and two U.S. ESA tools – mean annual funding and peer-reviewed scientific information. However, correlations with other variables differ greatly depending on how recovery is defined. Species threats and recovery actions are also moderately related to their abundance and range trends.

Reptiles are the vertebrate taxon with the highest percentage of at-risk species in Canada, many of which exist at the northern limit of their species’ home range in Ontario. Numerous reptiles are found in the Georgian Bay area; however, factors limiting their distribution in Ontario are poorly understood. It is likely that the thermal and hydrological conditions of a reptile’s critical habitat are contributing factors. Specifically, peatlands serve as ideal hibernacula for the threatened Eastern Massasauga Rattlesnake (Sistrurus catenatus) while moss cushions may provide freshwater turtles, including the threatened Blanding’s Turtle (Emydoidea blandingii) and endangered Spotted Turtle (Clemmys guttata), with nesting opportunities on open rock barrens. Although different in their functional purpose at opposite life stages for two separate orders of reptiles, these ecosystems provide suitable conditions to meet the physiological needs of the reptiles utilizing them. This analysis characterizes the thermal and hydrological conditions of moss-dominated ecosystems from a reptile species-at-risk perspective. The interaction between the water table and the frost line is important when assessing the winter survival of Eastern Massasauga Rattlesnakes hibernating in peatland hummocks. Larger hummocks are more ideal as they have a lower chance of becoming flooded in the winter while still providing protection from the advancing frost line. Ideally, hummocks that are 30-35 cm tall provide the greatest chance of survival when snakes hibernate 20-25 cm below the surface. Subsurface temperatures in relation to snow depth, as it is influenced by tree stand characteristics, was also assessed. This resulted in the conclusion that the presence, absence, timing, and frequency of freeze and thaw events is likely more important than snow depth when it comes to winter survival. Similar to rattlesnake hibernacula, turtle nests can be inundated for extended periods of time or exposed to extreme temperatures which reduces their chance of survival. The water storage dynamics of 22 hillslope and 12 hilltop moss cushions along with the temperature dynamics at nine locations were characterized. Although it was determined hilltop locations had greater water storage capabilities, continuously monitored moss cushions responded very quickly to rainfall events whereby sites were inundated for less than 12 hours. Average subsurface temperatures decreased with depth as did temperature fluctuations, both of which were positively correlated but not significantly affected by canopy openness. However, due to their tendency to grow on flat surfaces, not all moss cushions are suitable nesting sites. Moreover, temperatures that ensure proper development and equal ratios of male-to-female turtles were not achieved suggesting that this is a potential factor limiting the northern distribution of turtles in Ontario. In order to properly asses the vulnerability of these populations to threats including habitat loss and climate change, the habitat requirements of different species at critical life stages needs to be understood. Therefore, conservationists can use this study to implement mitigation strategies that consider impacts on the thermal and hydrological dynamics within reptile habitat. / Thesis / Master of Science (MSc)

No description available.

No description available.

The development and implementation of effective species and population-specific management strategies requires population-specific information. To demonstrate the relative extirpation risk associated with various road mortality scenarios for a population of Blanding’s turtles at Canadian Nuclear Laboratories in Chalk River, Ontario, a Population Viability Analysis was conducted. Road mortality of two adult females every ten years resulted in population extirpation within 200 years relative to a stable population not experiencing road mortality. To accommodate informed decision-making for the management of this species at risk, the movement patterns and habitat selection of this Blanding’s turtle population were described. There was no significant difference between males and females in distance moved between relocations in either the spring or the summer, but turtles moved greater distances in the spring than in the summer. Annual and seasonal home range size did not differ between the sexes or between spring and summer periods. A compositional analysis indicated Blanding’s turtles preferred marsh habitats over bog, swamp, lake, and upland. Matched-paired logistic regression was used to determine selection of microhabitat features, such as type of vegetation, in the spring and summer. Turtles preferred sites with warmer air temperatures, shallower water, a higher availability of open water, and greater coverage of emergent and floating vegetation types in the spring period. In the summer period, turtles preferred sites characterized by cooler, deeper water, a higher availability of open water, and greater coverage of emergent and floating vegetation types. This population of Blanding’s turtles appears to be relatively small and the continued threat of road mortality indicates a delicate situation for its persistence. Considering seasonally preferred habitats will best inform management decisions for seasonal work restrictions and future development plans.

Place-based biological conservation planning and recovery delineates “places” – spatial extents with favourable conditions for the recovery and management of multiple species simultaneously. Places represent geographic areas where constituent species are more likely to benefit from a specific set of recovery and management actions. Currently, place-based conservation planning is focused on prioritizing already-identified places. Findlay and McKee (2016) propose an approach to identify and delineate places by grouping geographical units based on species-at-risk (SAR) co-localization in (a) geographical, and (b) threat space. The following research is a practical application of the Findlay-McKee Methodology (FMM), using southern Ontario as a case study. I develop a parameterized algorithm to operationalize the design principles laid out in the FMM. I first define metrics to characterize the variation in SAR overlap and the degree to which sets of SAR share common threats. Next, I explore how the spatial extent of places (place size) changes as a function of tolerance for dissimilarity in both measures. The case study allowed me to evaluate the benefits and limitations of the FMM. I conclude that the FMM has the potential to be a defensible method for characterizing places based on SAR community overlap and inter-species threat similarity. However, the FMM’s applicability is limited by the availability of datasets at an appropriate resolution for analysis; uncertainty in selecting appropriate thresholds of tolerance for dissimilarity; and the criteria used to designate seed planning units. Given the increasing popularity of multi-species and ecosystem level recovery and conservation management, developing an efficient and effective process to guide place selection is crucially important. I recommend further research focus on empirically determining the number of places in a planning region and identifying at what tolerance thresholds places lose their ability to delineate areas where a comparatively small number of recovery actions will confer widespread benefits.