Theses and Dissertations at Montana State University (MSU)
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Item Spatiotemporal patterns of resource use and density of American black bears on Yellowstone's northern range(Montana State University - Bozeman, College of Letters & Science, 2020) Bowersock, Nathaniel Roth; Chairperson, Graduate Committee: Andrea Litt; Andrea R. Litt, Kerry A. Gunther, Jay J. Rotella, Jerod A. Merkle and Frank T. van Manen were co-authors of the article, 'Influence of resource waves on American black bears during Spring in the northern range of Yellowstone National Park' which is contained within this thesis.; Andrea R. Litt, Kerry A. Gunther, Michael A. Sawaya, Jay J. Rotella and Frank T. van Manen were co-authors of the article, 'Factors associated with varying density of black bears on Yellowstone National Park's northern range' which is contained within this thesis.The availability of resources, such as food and cover, can directly influence the movement and distribution of wildlife populations. The abundance and seasonal timing of many resources have changed in Yellowstone National Park (YNP), which has influenced populations of American black bears (Ursus americanus), an opportunistic omnivore. Previous studies have focused on how changes in resources have influenced black bears in the central and southern regions of YNP, however little work has focused on black bears in the northern part of the park. In 2017-2018, we used GPS collars and non-invasive genetic sampling to understand resource selection and variation in densities of black bears on the Northern Range. We sought to 1) assess whether black bears were following seasonal pulses of resources (resource waves) in the spring, such as the green wave and elk (Cervus canadensis) calving wave and 2) evaluate how densities of black bears varied based on landscape features, generating a baseline abundance estimate to help track changes in the population over time. We found evidence that black bears followed the green wave, prioritizing forage quality over quantity when selecting patches of green vegetation in early spring. However, black bears were less likely to select areas near historical elk calving grounds, suggesting that consumption of neonates is more opportunistic. Densities of black bears varied among vegetation communities, with the highest densities in forested communities dominated by Douglas fir. Our study provides the first baseline density estimates for black bears on the Northern Range, with an average density of 12.8 bears/100km 2 (95% CI = 9.4 - 17.5), which is higher than other regions in YNP. Availability of high-quality resources may allow for higher densities of black bears, with potential ramifications for other wildlife populations on the Northern Range. Information about resource selection and variation in estimated densities could be used to guide management decisions to continue to reduce human-bear conflicts and provide safe wildlife viewing experiences for the growing number of visitors to YNP.Item The spatial ecology and mating system of black bears (Urus americanus) in New Mexico(Montana State University - Bozeman, College of Letters & Science, 2008) Costello, Cecily Marie; Chairperson, Graduate Committee: Scott CreelIn summary, our results show that high rates of male dispersal and female philopatry combine to create a spatial genetic structure that generates low rates of inbreeding and little need for kin discrimination among potential mates. Thus, evidence supports the hypothesis that inbreeding avoidance is achieved by means of male-biased dispersal in black bears. Our results also suggest the general pattern of male-biased dispersal is modified by competition for mates or resources.Item Black bear (Ursus americanus) ecology in Southern Grand Teton National Park(Montana State University - Bozeman, College of Letters & Science, 2011) Frattaroli, Leslie Marie; Chairperson, Graduate Committee: Scott Creel; Chuck Schwartz (co-chair)Black bears (Ursus americanus) in Grand Teton National Park (GRTE), Wyoming occupy an environment that is changing due to human pressure and environmental variability. I analyzed activity patterns, food habits, and habitat use of black bears in southern GRTE, trying to identify if human recreation impacted these patterns. I studied 9 black bears equipped with spread spectrum technology (SS) collars from June, 2005 to October, 2006. Each collar contained -15° head to tail activity switch, a GPS radio receiver, and an independent very high frequency (VHF) transmitter. I used logistic regression on a sample of bear locations that were field-verified as active or resting to determine a break point to classify all locations as resting or active based upon activity counts. My discriminant analysis indicated that bears were likely resting if their recorded activity count was <16.5. I used logistic regression to determine which factors were most responsible for missed fixes. Overall, bear activity levels were consistent regardless of their distance from roads, human developments, and trails. Bears fed on a wide range of foods including vegetation, insects, and mammals that were seasonally abundant. Graminoids and ants were important food sources for black bears in the spring and summer. I used the Mahalanobis Distances Factor Analysis (MADIFA) to quantitatively break down the D ² statistic into linear combinations to determine the impact of each variable on D ². My models displayed areas of high use (i.e. larger D ² values), in forested regions adjacent to trails and roads. Several axes in different linear combinations, including habitat and human use covariates, are present in the analysis. This suggests that a complexity exists for black bear habitat use, beyond proximity to human use activities. Therefore it would be an oversimplification to conclude that black bears only utilize areas close to trails and/or roads in southern GRTE.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.Item The use of wildlife underpasses and the barrier effect of wildlife guards for deer and black bear(Montana State University - Bozeman, College of Letters & Science, 2011) Allen, Tiffany Dore Holland; Chairperson, Graduate Committee: Scott Creel; Marcel P. Huijser, David W. Willey, Whisper Camel, Pat Basting and Dale Becker were co-authors of the article, 'The effect of structural characteristics, landscape parameters, and human disturbance on the use of underpasses by deer and black bear' in the journal 'Journal of wildlife management' which is contained within this thesis.; Marcel P. Huijser and David W. Willey were co-authors of the article, 'Evaluation of wildlife guards at access roads' in the journal 'Wildlife society bulletin' which is contained within this thesis.Roads and traffic affect wildlife on multiple organizational scales (e.g. from individuals to populations) and different spatial scales (e.g. local patch to landscapes). Roads not only affect the natural environment, but people are also at risk when animals are on the road. As transportation agencies are incorporating mitigation measures into roadway design, more opportunities are arising to study their effectiveness. One such opportunity is along U.S. Highway 93 on the Flathead Indian Reservation in Montana, where eight reconstruction projects over 90.6 km were completed in 2010. The mitigation measures include 2.4-m fencing, crossing structures, and wildlife guards. These measures are aimed at reducing wildlife-vehicle collisions and increasing human safety, while allowing unimpeded wildlife movement and traffic flow. Within the 90.6-km reconstruction zone, two sections were completed in 2006. For this study, we focused on these two sections to answer two questions: 1) To what extent are the wildlife guards a barrier to wildlife, especially deer (Odocoileus sp.)?; and 2) How do characteristics of the underpasses, landscape characteristics, and human disturbance influence use by mule deer (O. hemionus), white-tailed deer (O. virginianus), and black bear (Ursus americanus)? To answer the first question, we monitored wildlife movements with cameras at two guards and in one culvert adjacent to a guard. To answer the second question, we used both sand tracking beds and cameras to monitor 11 underpasses for over two years. We also analyzed data on structural characteristics, landscape characteristics, and human disturbance from field measurements and a geographic information system. The guards were > or =85% effective as a barrier to deer, and 93.5% of deer used the crossing structure instead of the adjacent guard. Though the guards were not an absolute barrier, the results indicate deer were substantially discouraged from crossing, and the vast majority crossed the road using the crossing structure rather than the guard, indicating the guards are an effective means of mitigation. We found that increasing distance to cover may increase mule and white-tailed deer use of underpasses. However, we were unable to determine factors related to black bear crossings. We recommend further study for all three species.