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 Permeability of three-strand electric fences by black bears and grizzly bears(Montana State University - Bozeman, College of Agriculture, 2018) Johnson, Brittani Justine; Chairperson, Graduate Committee: Lance McNewElectric fencing has been used to deter bears in North America for several decades. Producers have turned to a design of a minimum of five-wire electric fence as their primary solution to reduce livestock depredation and to reduce raids of chicken houses and beeyards. However, these designs are expensive and reducing the number of wires used in a design to three wires would be beneficial. Scientific evaluations of the efficacy of three-wire electric fencing at deterring bears is lacking. In 2015 and 2016, I conducted a study in the Blackfoot Valley of Montana to evaluate the efficacy of rapid-deployment electric fencing designs in deterring bears from baited enclosures. Baited enclosures of two fencing configurations were established at 20 sites in the study area. Each enclosure was systematically energized and unenergized for 3-day periods; and passage into the enclosure was monitored with trail cameras to provide information on effectiveness and permeability. I recorded 134 visits by bears to fenced enclosures during the study seasons of 2015 and 2016. Of these visits, 78 occurred in 2015 and included 57 black bears and 21 grizzly bears. Fifty-six visits occurred in 2016, including 34 black bears and 22 grizzly bears. Black bears and grizzly bears were successful at passing the short fence 48% (95% CI: 32.0 -- 63.6) and 23% (5.0 -- 53.8) of the time, respectively, when it was not energized. When the short fence was energized, black bears were 7% (0.2 -- 33.9) successful in passing, whereas grizzly bears were successful in 25% (5.5 -- 57.2) of attempts. When not energized, both species successfully passed the tall fence design in 58% (95% CI: 27.7 -- 84.8) of attempts. Black bears and grizzly bears successfully entered energized enclosures with tall fences in 30% (95% CI: 13.2 -- 52.9) and 0% (95% CI: 0.0 -- 45.9) of attempts, respectively. Both fence types deterred bears from entering baited enclosures and all fences allowed less than perfect access when unenergized, suggesting that even minimalistic configurations of electric fences may act as barriers to black and grizzly bears. Further study evaluating the effects of rapidly increasing construction of electric fencing is needed to assess landscape level effects on bear movement and habitat selection.Item Black bear habitat use in west-central Idaho(Montana State University - Bozeman, College of Letters & Science, 1984) Unsworth, James W.Item Ecology of black bears on the Beartooth Face, south-central Montana(Montana State University - Bozeman, College of Letters & Science, 1988) Mack, John AndrewItem Home range, habitat use, and food habits of black bears in south-central Montana(Montana State University - Bozeman, College of Letters & Science, 1987) Greer, Scott QuentinItem The ecology of grizzly bears and black bears in the Cooke City, Montana area(Montana State University - Bozeman, College of Letters & Science, 2001) Yonge, Steven RichardItem The biogeography of Montana black bear genetics(Montana State University - Bozeman, College of Letters & Science, 1998) Ostheimer, William AllenItem 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.