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—Moonwort (Botrychium Swartz) is a genus of ferns found in high diversity in the Rocky Mountains of southwestern Alberta, Canada. These small, cryptic plants are thought to prefer disturbed areas, such as trail sides. However, this idea may result from survey bias toward accessible areas near trails, or greater ease of spotting these plants in barren areas. Castle Provincial Park and Castle Wildland Provincial Park (CCWPP) are 2 recently established protected areas within this global hotspot of Botrychium diversity. Prior to 2018, provincial and international databases included only 30 records of Botrychium throughout CCWPP. Therefore, their frequency in the parks and their habitat preferences are not well understood. We used new records from the Castle region plus online herbarium records to build a genus-level species distribution model (SDM) and surveyed 24 sites of varying predicted suitability at least 100 m from trails. We then used all known records, including new records gathered during vegetation surveys, to assess habitat associations of any Botrychium species found throughout CCWPP. Botrychium occurred in a wide variety of vegetation types, with some species limited to one vegetation type. Overall, most Botrychium occurrences were on south-facing slopes, in grassland vegetation, 10–100 m away from official marked trails. We discovered 7 new occurrences in surveys at least 100 m from trails. Although 6 of the 7 new off-trail occurrences were found at sites with >40% suitability, the SDM was not a significant predictor of Botrychium occurrence. Our results show that Botrychium occurs across a wide range of vegetation types, topographic conditions, and proximity to trails and there are likely many undiscovered populations in CCWPP.

Iiniiksi (plains bison; Bison bison) are ecocultural keystone species that have coevolved in sacred reciprocal relationships with Siksikaitsitapi (Blackfoot People) and nonhuman Saokio (prairie) relatives since time immemorial. The historic decimation of native prairie and Iiniiksi, along with the displacement of Indigenous plains peoples, disrupted this web of prairie interrelationships, creating an imbalance in the grassland ecosystem and the Siksikaitsitapi way of life. Grounded in Blackfoot Ecological Knowledge (BEK) and Siksikaitsitapi Science (SS), my research explores interactions amongst soil, plants, and people resulting from Iinnii rematriation (the return of sacred ways that centers and restores responsibilities and relationships) to Kainaissksaahkoyi (Blood Reserve / Kainai First Nation) to offer a path forward for healing these sacred relationships. I characterized soil and plant communities in nine paired ungrazed and grazed sites on the Kainai Iinnii Rangelands two and three growing seasons after Iinnii returned. I gathered Iinnii relational BEK with five Blackfoot Elders and Knowledge Keepers to better understand the social effects of Iinnii rematriation. After one year of Iinnii grazing, there were no significant differences in soil, plant communities, or the occurrence of traditional plants. Long-term monitoring is needed to capture future Iinnii effects on the landscape. Blood Tribe Land Management (BTLM) can use essential baseline data collected in this study for an Indigenous-led community-based monitoring program. Synthesizing BEK with Western Science (WS) provided invaluable insight to reconnect people to Iinnii and Saokio and guide future Iinnii reintroduction and grassland stewardship efforts.

Species distribution models (SDMs) have become a widely used tool for understanding species distributions and informing conservation actions. However, user decisions made during model development can impact model predictions and performance. In this thesis, I address the sensitivity of model predictions and performance to several modeling decisions. I first reviewed modeling decisions used in studies that validated SDMs with independent data and found that the impacts of some decisions (i.e., choice of geographic study extent) have yet to be fully tested using independent data. I then used independent data to test the impacts of study extent on SDMs for six amphibian species at the edge of their respective ranges in western Canada. I found that model predictions were highly sensitive to the study extent used, and that many models failed to accurately predict independent occurrence regardless of the study extent used. Following from this result, I explored the joint impacts of choice of study extent, the type of environmental data used, and whether sampling bias was accounted for in SDMs developed to inform conservation translocations of long-toed salamanders. I found that these decisions impacted the prioritization of potential release sites, and that models developed using random background points and local study extents tended to perform best. In this study I also demonstrated an approach for incorporating future climatic predictions into the selection of potential release sites and found that tradeoffs exist between developing accurate models and those that can make future predictions without extrapolation beyond the conditions with which models were generated. Overall, my thesis contributes several validated SDMs for use in amphibian conservation in western Canada while simultaneously adding to our understanding of how key modeling decisions can impact SDM predictions, performance, and downstream conservation decisions.

I measured the effect of recreational trails on plant species richness, community composition, and the presence of exotic and rare species in the Castle Provincial Parks of Alberta, Canada, by surveying 142 transects adjacent to or far from trails. I also characterized the habitat of species from the rare genus Botrychium Swartz and tested a species distribution model (SDM) to identify suitable Botrychium habitat. Plant communities near trails had higher species richness, shifts in composition, and greater occurrence of exotic plant species. These effects extended farther from off-highway vehicle (OHV) trails than from footpaths, but only in mixed/broadleaf and shrubland vegetation. The SDM was not a strong predictor of Botrychium presence, but I found Botrychium in 29% of surveyed sites. To minimize trail effects such as colonization by exotic species, managers should prioritize closing trails to OHVs or limiting OHV traffic, particularly in mixed/broadleaf and shrubland vegetation.

Species distribution models (SDMs) are widely used in ecology. In theory, SDMs capture (at least part of) species' ecological niches and can be used to make inferences about the distribution of suitable habitat for species of interest. Because habitat suitability is expected to influence population demography, SDMs have been used to estimate a variety of population parameters, from occurrence to genetic diversity. However, a critical look at the ability of SDMs to predict independent data across different aspects of population biology is lacking. Here, we systematically reviewed the literature, retrieving 201 studies that tested predictions from SDMs against independent assessments of occurrence, abundance, population performance, and genetic diversity. Although there is some support for the ability of SDMs to predict occurrence (~53% of studies depending on how support was assessed), the predictive performance of these models declines progressively from occurrence to abundance, to population mean fitness, to genetic diversity. At the same time, we observed higher success among studies that evaluated performance for single versus multiple species, pointing to a possible publication bias. Thus, the limited accuracy of SDMs reported here may reflect the best-case scenario. We discuss the limitations of these models and provide specific recommendations for their use for different applications going forward. However, we emphasize that predictions from SDMs, especially when used to inform conservation decisions, should be treated as hypotheses to be tested with independent data rather than as stand-ins for the population parameters we seek to know.

Plant communities are changing in response to natural and anthropogenic drivers. However, we know little about how different drivers have affected Rocky Mountain plant communities over the past few decades. In 2017, a wildfire burned 50% of the vegetation at Waterton Lakes National Park, located in Canada’s southern Rocky Mountains. Using re-surveys of vegetation plots established in the 1990s, I quantified changes in plant community diversity and composition over the past two decades. I found that fire severity interacted with human disturbance to affect species richness and community composition. I also found that burned and unburned plots are experiencing diverging trajectories. Herbaceous and short-lived species have become more prominent in burned plots, whereas unburned plots are becoming increasingly characterized by woody species. Ecologists should continue conducting legacy studies as they have the potential to expand our theoretical understanding of community assembly and inform management decisions.

Species distribution models (SDMs) are used to test ecological theory and to direct targeted surveys for species of conservation concern. Several studies have tested for an influence of species traits on the predictive accuracy of SDMs. However, most used the same set of environmental predictors for all species and/or did not use truly independent data to test SDM accuracy. We built eight SDMs for each of 24 plant species of conservation concern, varying the environmental predictors included in each SDM version. We then measured the accuracy of each SDM using independent presence and absence data to calculate area under the receiver operating characteristic curve (AUC) and true positive rate (TPR). We used generalized linear mixed models to test for a relationship between species traits and SDM accuracy, while accounting for variation in SDM performance that might be introduced by different predictor sets. All traits affected one or both SDM accuracy measures. Species with lighter seeds, animal-dispersed seeds, and a higher density of occurrences had higher AUC and TPR than other species, all else being equal. Long-lived woody species had higher AUC than herbaceous species, but lower TPR. These results support the hypothesis that the strength of species–environment correlations is affected by characteristics of species or their geographic distributions. However, because each species has multiple traits, and because AUC and TPR can be affected differently, there is no straightforward way to determine a priori which species will yield useful SDMs based on their traits. Most species yielded at least one useful SDM. Therefore, it is worthwhile to build and test SDMs for the purpose of finding new populations of plant species of conservation concern, regardless of these species’ traits.

Aims: It is important to understand the effect of landscape context on biological communities to predict how biodiversity will be affected on human-dominated land-scapes. While many studies have tested the effects of landscape context on the spe-cies richness and composition of vascular plants, few have compared the responses of vascular plants and bryophytes on the same landscape. We sampled non-epiphytic bryophytes and vascular plants in 184 plots to test whether three landscape context factors measured four years or four decades previously could predict bryophyte or vascular plant species richness and composition after accounting for local factors.Location: Temperate forests and oak savannahs, Vancouver Island, British Columbia, Canada.Methods: We used model selection and comparisons to test the effects of surround-ing road density, total amount of forest, and distance to the nearest forest edge on species richness, species richness of non-disturbance-associated species, and com-munity composition after controlling for important local predictors including sub-strate availability and topography.Results: The species richness of non-disturbance-associated vascular plants was lower in plots with greater surrounding historical road density, and perennial stayer bryophyte richness declined with increasing historical road density and lower histori-cal forest amount, suggesting a potential extinction debt. Landscape context signifi-cantly affected total species richness and community composition of vascular plants, but not bryophytes.Conclusion: While bryophytes appear to be less sensitive overall to landscape con-text than vascular plants, disturbance-intolerant perennial stayer bryophytes may decline in the future in response to the increased road density and loss of forest cover that has occurred over the past four decades.

Fully 37% of species listed under Canada’s Species at Risk Act (SARA) are plants or lichens. The law does not automatically protect species on private land, and it is unknown how many at-risk plants grow mainly on private land. We analyzed official status reports and related documents for 234 plant species at risk to determine land tenure and evaluated differences in threats and changes in status. We also assessed how well plants were represented in two federal programs: the Natural Areas Conservation Program (NACP) and the Habitat Stewardship Program (HSP). Of SARA-listed plant species, 35% have the majority of their known populations on private land while <10% occur mostly on federal land. Species growing mainly on private land were no more or less likely to decline in status over time compared with others. Plant species at risk were less likely than other taxonomic groups to be found on land protected under the NACP. The proportion of HSP projects targeting plants is well below the expected proportion based on the number of listed species. We recommend that policy-makers promote and prioritize actions to increase the representation of plant species in federally funded programs, especially on private lands.

1. When deforestation results in small forest fragments surrounded by a non‐forest matrix, forest stands within these fragments experience changes in structure and community composition. They also continue to experience natural disturbances like hurricanes and ice storms. It remains unclear whether the landscape context of forest stands influences plant community response to natural disturbances.2. Using data from surveys of forested plots in the years immediately following and 19 years after a severe ice storm, we measured changes in woody stem density, species richness and beta diversity.3. Plots with greater storm damage had greater gains in stems and species, and greater shifts in community composition. In addition, there were interactions between the degree of storm damage and landscape context. The short‐term ef‐fects of storm damage were magnified in plots with less forest on the surrounding landscape and farther from the forest edge. In plots with high damage, a return towards pre‐storm conditions over the long‐term occurred more often in plots farther from the forest edge compared to those close to the edge.4. Synthesis. Future climate scenarios predict increases in severe weather and accompanying ecosystem disturbance. Our results show that it is important to consider landscape context when assessing the response of forest communities to such disturbances.

Pollution is a pervasive, albeit often invisible, threat to biodiversity in Canada. Currently, the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) relies on expert opinion to assess the scope (i.e., the proportion of a species’ population that may be affected) of pollution to species at risk. Here, we describe a spatially explicit, quantitative method for assessing the scope of pollution as a threat to species at risk in Canada. Using this method, we quantified the geographic co-occurrence of 488 terrestrial and freshwater species and pollution sources and determined that, on average, 57% of the mapped occurrences of each species at risk co-occurred with at least one pollution source. Furthermore, we found a weak correlation between the scope of the threat of pollution as assessed by COSEWIC expert panels and the geographic overlap of species occurrences and pollution sources that we determined with our quantitative method. Experts frequently identified scope of pollution as absent or negligible even for species with extensive co-occurrence with pollution sources, especially vascular plants. Clearly, a quantitative approach is needed to make accurate estimates of the scope of pollution as a threat to species at risk in Canada.