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Item Evaluating bear management areas in Yellowstone National Park(Montana State University - Bozeman, College of Letters & Science, 2022) Loggers, Elise Ahlenslager; Chairperson, Graduate Committee: Andrea Litt; This is a manuscript style paper that includes co-authored chapters.A growing body of research suggests large predators change their behavior near humans in ways that parallel how prey respond to predators; when outdoor recreation increases, avoiding humans becomes more difficult. Restricting human access to reduce detrimental effects of human-wildlife interactions can be an attractive management tool, however, rarely is the efficacy of such measures assessed. In 1982, Yellowstone National Park began instituting short-term, annual restrictions to areas of the backcountry containing important food resources for grizzly bears (Ursus arctos). These areas -- Bear Management Areas (BMAs) -- were intended to reduce human-caused disturbance of foraging bears and improve visitor safety. We sought to assess whether grizzly bears: 1) preferred BMAs with access restrictions more than other areas in YNP and 2) changed their response to sporadic (trail) and predictable (campsite) recreation sites depending on BMA access restrictions. We modeled resource selection of grizzly bears with step-selection functions, based on GPS locations from male and female bears collected from 2000 to 2020. Our analyses demonstrated that grizzly bears differentially selected BMAs, compared to areas outside BMAs, and that selection changed with sex and season. Bears likely prefer BMAs for the resources they contain more than to avoid people as only males changed their selection of BMAs based on access restrictions. Males avoided hiking trails during the day, but preferred trails at night. Females changed their selection of trails depending on human access restrictions and avoided trails in unrestricted BMAs. Combined with previous work, results suggest bears capitalize on the environment to avoid human presence, often with sex-specific strategies. For sporadic recreation, males temporally avoid the perceived risk of people whereas females spatially avoid the perceived risk of people. Although lower-intensity activities often are thought of as compatible with conservation, such recreation may be cryptic, but important, drivers of behavioral change in wildlife.Item Wolverine habitat quality, connectivity, and prioritization at the landscape scale(Montana State University - Bozeman, College of Letters & Science, 2019) Carroll, Kathleen Anne; Chairperson, Graduate Committee: Andrew J. Hansen; Andrew J. Hansen, Robert M. Inman and Rick L. Lawrence were co-authors of the article, 'Comparing methods to disentangle habitat predictors for wolverines in the southern extent of their distribution' which is contained within this dissertation.; Andrew J. Hansen, Robert M. Inman, Rick L. Lawrence and Andrew B. Hoegh were co-authors of the article, 'Testing landscape resistance layers and modeling connectivity for wolverines in the western US' which is contained within this dissertation.; Robert M. Inman, Andrew J. Hansen, Kevin Barnett and Rick L. Lawrence were co-authors of the article, 'Prioritizing metapopulation connectivity for wolverines' which is contained within this dissertation.The core of conservation biology is understanding how to mitigate the impacts of anthropogenic activities on species. These impacts are particularly detrimental to isolated and small populations, which face extirpation or extinction without immediate conservation action. For small and isolated populations, protecting connective habitat (e.g., corridors) and facilitating movement is key. Corridor identification requires rigorous planning and appropriate statistical choices to ensure that resulting conservation actions are defensible and best support ecological processes. This manuscript asks: 1) how do different, commonly used statistical methods inform our understanding of species resource selection across scale and between sexes, 2) how does landscape resistance and connectivity differ between resident and dispersing individuals, and 3) what information is important to include in a systematic conservation plan to best support on-the-ground conservation between land trusts, landowners, and other practitioners under future climate change conditions. To address each of these questions we focused on wolverines (Gulo gulo), which exist as isolated metapopulations across the western contiguous United States. Our key findings included that 1) the importance of habitat variables differ only slightly by sex, across selection scales, and across analysis methods, 2) dispersing animals are less sensitive to habitat quality compared to resident animals, and 3) including information that both helps mitigate potential threats and preserves ecological processes is the best approach for connectivity conservation planning. This work represents the most comprehensive wolverine connectivity conservation analyses to date. This research suggests that examining multiple approaches and validating results is critical to generating rigorous and defensible conservation decisions are being made for wolverines, although more studies are needed to validate this in other species. Taken together, this research provides land managers, policy makers, and scientists with guidance for future connectivity analyses, conservation action for wolverines, and a research framework that can be applied to additional species of conservation concern in isolated populations.Item A multi-scale assessment of animal aggregation patterns to understand increasing pathogen seroprevalence(Ecological Society of America, 2014-10) Brennan, Angela; Cross, Paul C.; Higgs, Megan D.; Edwards, W. Henry; Scurlock, Brandon M.; Creel, ScottUnderstanding how animal density is related to pathogen transmission is important to develop effective disease control strategies, but requires measuring density at a scale relevant to transmission. However, this is not straightforward or well-studied among large mammals with group sizes that range several orders of magnitude or aggregation patterns that vary across space and time. To address this issue, we examined spatial variation in elk (Cervus canadensis) aggregation patterns and brucellosis across 10 regions in the Greater Yellowstone Area where previous studies suggest the disease may be increasing. We hypothesized that rates of increasing brucellosis would be better related to the frequency of large groups than mean group size or population density, but we examined whether other measures of density would also explain rising seroprevalence. To do this, we measured wintering elk density and group size across multiple spatial and temporal scales from monthly aerial surveys. We used Bayesian hierarchical models and 20 years of serologic data to estimate rates of increase in brucellosis within the 10 regions, and to examine the linear relationships between these estimated rates of increase and multiple measures of aggregation. Brucellosis seroprevalence increased over time in eight regions (one region showed an estimated increase from 0.015 in 1991 to 0.26 in 2011), and these rates of increase were positively related to all measures of aggregation. The relationships were weaker when the analysis was restricted to areas where brucellosis was present for at least two years, potentially because aggregation was related to disease-establishment within a population. Our findings suggest that (1) group size did not explain brucellosis increases any better than population density and (2) some elk populations may have high densities with small groups or lower densities with large groups, but brucellosis is likely to increase in either scenario. In this case, any one control method such as reducing population density or group size may not be sufficient to reduce transmission. This study highlights the importance of examining the density-transmission relationship at multiple scales and across populations before broadly applying disease control strategies.Item Using noninvasive genetic sampling methods to estimate demographic and genetic parameters for large carnivore populations in the Rocky Mountains(Montana State University - Bozeman, College of Letters & Science, 2012) Sawaya, Michael Allen; Chairperson, Graduate Committee: Steven Kalinowski; Toni K. Ruth, Scott Creel, Jay J. Rotella, Jeffrey B. Stetz, Howard B. Quigley, and Steven T. Kalinowski were co-authors of the article, 'Evaluation of noninvasive genetic sampling methods for cougars in Yellowstone National Park' in the journal 'Journal of wildlife management' which is contained within this thesis.; Jeffrey B. Stetz, Anthony P. Clevenger, Michael L. Gibeau and Steven T. Kalinowski were co-authors of the article, 'Estimating grizzly and black bear population abundance and trend in Banff National Park using noninvasive genetic sampling methods' in the journal 'PLoS ONE' which is contained within this thesis.; Anthony P. Clevenger, and Steven T. Kalinowski were co-authors of the article, 'Wildlife crossing structures connect ursid populations in Banff National Park' in the journal 'Conservation biology' which is contained within this thesis.; Steven T. Kalinowski, and Anthony P. Clevenger were co-authors of the article, 'Gene flow at wildlife crossing structures in Banff National Park' in the journal 'Molecular ecology' which is contained within this thesis.Healthy carnivore populations are important to maintaining ecosystem balance, but many species are declining globally at disturbing rates due to anthropogenic causes. To effectively manage and conserve carnivores, wildlife managers must be able to obtain reliable estimates of population parameters. Noninvasive genetic sampling (NGS) methods such as hair or scat collection offer new and exciting alternatives to traditional carnivore research methods involving capture, drugging, and handling of animals; however, the potential of NGS methods to answer applied ecological questions has not been fully realized. The main objective of my doctoral research was to develop and apply NGS methods to estimate demographic and genetic parameters for large carnivore populations in the Rocky Mountains. First, I evaluated two NGS methods, hair snares and snow tracking, for cougars (Puma concolor) in Yellowstone National Park. I developed a method to collect hair while following cougar tracks in snow to bed sites and natural hair snags (e.g. thorn bushes, branch tips) from which I demonstrated that samples collected using NGS can provide reliable information on cougar population abundance. Next, I compared the ability of two NGS methods, hair traps and bear rub surveys, to estimate population abundance and trend of grizzly (Ursus arctos) and black bears (U. americanus) in Banff National Park. I found that bear rubs performed better than hair traps for estimating grizzly bear abundance and population growth rates, whereas hair traps worked better than bear rubs for black bears. I then used NGS to examine demographic and genetic connectivity at wildlife crossing structures along the Trans-Canada Highway that bisects Banff National Park. I compared genetic data collected from the bear populations surrounding the highway to data collected at the crossing structures using a novel hair sampling system. This comparison allowed me to show that wildlife crossing structures provided demographic connectivity for bear populations and maintained sufficient gene flow across the highway to prevent genetic isolation. In short, I have demonstrated the power of using an array of NGS methods, alone or in combination, to estimate abundance, gene flow, genetic structure, migration, and population growth rates for large carnivores in the Rocky Mountains.Item Use of stable isotopes to investigate black bear diets and to evaluate the human-bear management program at Yosemite National Park, CA(Montana State University - Bozeman, College of Letters & Science, 2011) Hopkins, John Brooks, III; Chairperson, Graduate Committee: Steven Kalinowski; Steven Herrero, Richard T. Shideler, Kerry Gunther, Charles C. Schwartz, and Steven T. Kalinowski were co-authors of the article, 'A proposed lexicon of terms and concepts for human-bear management in North America' in the journal 'Ursus' which is contained within this thesis.; Jake M. Ferguson was a co-author of the article, 'The rapid development of estimating assimilated diet using stable isotopes and an improved Bayesian mixing model' in the journal 'PLoS one' which is contained within this thesis.; Paul L. Koch, Jake M. Ferguson, Charles C. Schwartz and Steven T. Kalinowski were co-authors of the article, 'Stable isotopes to detect food-conditioned bears and evaluate human-bear management' in the journal 'Journal of Wildlife Management' which is contained within this thesis.; Paul L. Koch and Jake M. Ferguson were co-authors of the article, 'Use of stable isotopes to evaluate a century of human-bear management' in the journal 'Journal of Wildlife Management' which is contained within this thesis.Yosemite has applied extraordinary effort to manage people and bears over the past century. For the past decade, human-bear management has implemented both proactive (population-level) and reactive (individual-level) management to prevent bear incidents; however, incidents continue to occur at high frequency even though the program has received $500,000 in congressional funding each year since 1999. For this study, we developed a new method to detect human food-conditioned (FC) bears throughout the Park using isotopic data and used these results and dietary estimates for these bears to evaluate the effectiveness of the human-bear management program. In the first chapter, we proposed 40 definitions for terms and concepts common to human-bear management. In the second chapter, we provide details on a stable isotope mixing model designed to accurately estimate dietary parameters in the remaining two chapters. In these last chapters, we collected tissues (bone and hair) from contemporary and historic bears with known and unknown management statuses (FC or non-food-conditioned [NFC]) and analyzed them for their stable isotopic composition. In chapter 3, we used these isotopic data to predict the management status of unknown bears using a logistic regression model. For chapters 3 and 4, we used isotopic data for FC bears and stoichiometric data for their food sources to estimate the proportional dietary contributions to bear diets through time using our mixing model. Results from chapter 3 show a small proportion (~13%) of the unknown sampled population (n = 145) is currently FC, and chapter 4 results showed the proportion of human food in food-conditioned bear diets increased before the park began implementing a rigorous proactive human-bear management strategy in 1999. Since then, the amount of human food in known FC bear diets has decreased dramatically. We conclude that proactive human-bear management was effective at reducing the amount of human food available to bears since 1999. In contrast, evidence suggests reactive human-bear management was not effective at eliminating or reducing the amount of human food in individual bear diets. We suggest the Park reevaluate the effectiveness of their reactive human-bear management strategy, reduce problem bears from the population, and continue proactive management.