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Item Effect of landscape fragmentation on bat population dynamics and disease persistence in Uruguay(Montana State University - Bozeman, College of Agriculture, 2021) Botto Nunez, German; Chairperson, Graduate Committee: Raina K. Plowright; This is a manuscript style paper that includes co-authored chapters.The transmission of pathogens into novel host species, a process known as spillover, requires a series of conditions to align in space and time. A series of imperfect barriers prevent the jump of pathogens from one species to others. These may include the distribution and abundance of the primary host, the survival of the pathogen in the environment and the susceptibility of the recipient host to the pathogen. Only when permissive conditions align in time and space can the spillover occur. Spillovers may be relatively rare events and the understanding of the dynamics of the barriers is constrained by the ability of detecting and analyzing such events. Systems where spillover does not occur, despite apparent presence of all required conditions, provide an opportunity to understand barriers preventing inter-species transmission. Vampire bat-borne rabies in Uruguay provides such an opportunity. Despite large and stable livestock density, presence of vampire bats, and circulation of the virus in close proximity, the country did not experience livestock rabies outbreaks until 2007. Here we combined historical review, field sampling, and statistical and mathematical modeling to understand the factors driving the emergence of rabies in Uruguay in 2007 and the previous absence of the disease. Our results suggest that rabies outbreaks in the country are spatially and temporally associated with fragmentation of grasslands. We showed that proposed increased connectivity among colonies, in response to fragmentation, is sufficient to explain longer persistence of the virus in the bat colonies, allowing more opportunities for virus transmission to livestock. We showed that connectivity has a strong effect on rabies persistence and that reproductive seasonality and population turnover have only marginal effects compared to connectivity. As connectivity driven by shared feeding areas might not be detectable by genetic analyses of the bats, we proposed the use of a widespread virus persistently infecting bats as a marker to trace connectivity across colonies. Combined, the results presented here provide tools that can be applied to intervene and apply countermeasures to prevent spillover.Item Integrating livestock into small-scale vegetable farming systems(Montana State University - Bozeman, College of Agriculture, 2021) Benson-Feagler, Trestin Thea; Chairperson, Graduate Committee: Megan Van Emon; D.L. Regan, M.L. Van Emon and C.J. Yeoman were co-authors of the article, 'Effects of integrating livestock into small-scale vegetable farming systems' submitted to the journal 'Sustainable agriculture research' which is contained within this thesis.Since World War II, modern agriculture systems have shifted to low-diversity monoculture crops, specializing in a singular species and generally separating those crops from livestock. Such systems require high inputs including fertilizers, herbicides and tillage, all of which may reduce ecological potential of farmland. Small-scale farms are becoming more popular due to recent interest in local eating and sustainability. To improve their environmental sustainability, some small-scale farms have incorporated livestock back into cropping systems. Soil health measurements can be valuable in understanding the impacts livestock have on small- scale farming systems as soil is the growth medium for vegetation. The objectives of this study were to evaluate nutrient cycling, microbial communities and compaction in response to grazed versus un-grazed vegetable cropping systems and use this information to understand the interaction between soil biology, nutrient cycling and livestock when integrated in a variety of vegetable production systems. Soil and biomass samples were collected over three years (2017- 2020) before and after sheep grazing occurred on three farm locations in the Northern Great Plains. Soil samples were analyzed for soil microbial diversity, bulk density and soil nutrients. While I found no consistent differences in soil nutrients, bulk density or soil microbial diversity, my results indicate that integrating livestock into small-scale vegetable farming systems did not negatively impact soil quality. Results from this study may help demonstrate to farmers and livestock operators the importance of an integrated approach, for those that already practice this approach there is affirmation that integration is feasible and purposeful and also become the starting point for further research into a little studied topic.Item Effect of sainfoin (Onobrychis viciifolia Scop.) variety and harvest maturity on quality, yield, and condensed tannin content(Montana State University - Bozeman, College of Agriculture, 2020) Gardhouse, Kylie Ann; Chairperson, Graduate Committee: Megan Van EmonSainfoin (Onobrychis viciifolia Scop.) is a forage legume that was introduced to North America from Europe and Asia. Unlike alfalfa, sainfoin is non-bloating, lacks autotoxicity properties, and may work as an anthelmintic when consumed by livestock. With limited information available on sainfoin varieties and management, new information is necessary to provide to producers for optimal production. The objective of this study was to determine the impact of variety and maturity at harvest on forage yield, quality, and condensed tannin content. Four varieties of sainfoin ('AAC Mountainview', 'Eski', 'Shoshone', and 'Delaney') and one alfalfa variety ('Shaw') were planted at two locations in Montana and the same sainfoin varieties and one alfalfa variety ('Spredor 4') were planted in one location in Utah. Samples were taken at 10, 50 and 100% bloom and evaluated for dry matter production and nutritive quality. Variety (P < or = 0.005) and maturity (P < or = 0.001) both were found to impact production, with Shaw, AAC Mountainview and Eski varieties having higher production, as well as tonnage increasing with advancing maturity than Delaney and Shoshone. Sainfoin had greater levels of condensed tannins than alfalfa (P < or = 0.001), and within sainfoin, tannin content decreased with increasing maturity (P < or = 0.003) at all locations. Crude protein levels were significantly different for maturity (P < 0.001) and variety (P < or = 0.003), and fiber values were only affected by maturity (P < or = 0.001). These results demonstrate that sainfoin is a beneficial legume to feed to livestock particularly in grazing situations, with similar quality and yield compared to alfalfa, as well as a higher condensed tannin content.Item Native pollinators: the effects of livestock grazing on Montana rangelands(Montana State University - Bozeman, College of Agriculture, 2019) Blanchette, Gabrielle Elizabeth; Chairperson, Graduate Committee: Craig Carr; Michael A. Ivie (co-chair)Although native pollinators on rangelands serve, in part, as food at higher trophic levels, their primary ecosystem function is pollination. With 70% of western U.S. rangelands grazed by livestock, understanding how grazing affects native pollinators is a key component to managing rangelands, yet it is not well understood. In this study, I investigated how cattle grazing influences both diversity and abundance of native pollinators, including bees and wasps, syrphid flies, butterflies, and moths at two research locations for six to 10 weeks during the spring of 2016, 2017, and 2018. The first site, near Sidney, MT, served to understand if pollinators were more closely associated with active cattle grazing or rested pastures. The second site, near Roundup, MT, served to understand if pollinators were more associated with pastures either enrolled or not enrolled in the Sage Grouse Initiative, or pastures that had not experienced livestock grazing in previous seven years. Colored pan traps were deployed weekly in each treatment at each site. In addition to pollinator collections, weekly measurements of vegetation via Daubenmire frame were also collected. I collected 17,078 specimens at Sidney and 13,683 specimens at Roundup. My results suggest that in drier sagebrush landscapes, native pollinators are positively to neutrally associated with pastures moderately grazed by livestock. However, in mixed grass prairie landscapes that receive high precipitation, rest-rotational grazing does not appear to have a significant effect on primary native pollinators.Item Livestock depredation by grizzly bears on Forest Service grazing allotments in the Greater Yellowstone Ecosystem(Montana State University - Bozeman, College of Agriculture, 2017) Wells, Smith Laura; Chairperson, Graduate Committee: Lance McNewGrizzly bear population growth and range expansion over the last several decades in the Greater Yellowstone Ecosystem (GYE) has led to increased human-bear conflicts, including livestock depredation on public land grazing allotments. A better understanding of patterns and relationships between grazing allotment management and grizzly bear depredation of livestock is needed for adaptive, sustainable management in the ecosystem. Historic U.S. Forest Service and National Park Service livestock grazing records, grizzly bear habitat attributes, and documented livestock depredations by grizzly bears were collated for 316 public land grazing allotments within the grizzly bear Demographic Monitoring Area (DMA) during 1992-2014. Spatio-temporal relationships between annual livestock depredation counts and grazing allotment characteristics were modeled for each allotment during the study period at two spatial extents, representing daily and annual grizzly bear activity areas. As the Yellowstone grizzly population expanded during the last several decades, more public land grazing allotments were exposed to potential livestock-grizzly bear interactions and results indicated that both livestock stocking and grizzly bear habitat characteristics in and around allotments were related to documented depredations during 1992-2014. Annual numbers of livestock and grizzly bear density on allotments had a large, positive effect on average livestock depredation event counts. Allotment size and summer grazing both were related to higher depredation event counts while the presence of bulls and/or horses was related to lower counts. Allotments with less rugged terrain, lower road density, relatively higher vegetative primary productivity, greater amounts of whitebark pine, and further from forest edge on average were associated with higher average livestock depredation event counts. Managers and livestock producers could use these results to support adaptive management approaches and long-term planning such as increasing herd supervision, especially in areas with quality grizzly bear habitat and high grizzly bear density, or altering grazing management strategies and grazing locations to limit potential livestock depredation events. Results provide insight into historic livestock-grizzly bear conflicts on public lands in a large, complex ecosystem and although challenging, results could support cooperative management strategies to sustain the grizzly bear population and livestock operations in the GYE.Item Effects of livestock grazing management on the ecology of grassland birds and their predators in a northern mixed-grass prairie ecosystem(Montana State University - Bozeman, College of Agriculture, 2018) Vold, Skyler Thomas; Chairperson, Graduate Committee: Lance McNew; Lance B. McNew and Lorelle I. Berkeley were co-authors of the article, 'Effects of livestock grazing management on the ecology of grassland birds in a northern mixed-grass prairie ecosystem' submitted to the journal 'Rangeland ecology & management' which is contained within this thesis.; Lance B. McNew and Lorelle I. Berkeley were co-authors of the article, 'Effects of livestock grazing management on the occupancy of mesocarnivores in a northern mixed-grass prairie ecosystem' submitted to the journal 'The journal of wildlife management' which is contained within this thesis.Grassland birds have recently undergone substantial population declines throughout much of their historic ranges in North America. The majority of remaining grassland bird habitat is rangeland managed for livestock production, so grazing management has implications for grassland bird conservation efforts. Populations of mesocarnivores have recently seen range expansions and increased abundance as a result of anthropogenic extirpation of apex predators in grassland ecosystems. Mesocarnivores are often major predators of grassland birds and their nests, so considering the effects of management actions on mesocarnivore occupancy is important within grassland bird conservation efforts. I evaluated the relative effects of three livestock grazing systems on grassland bird abundance and mesocarnivore occupancy in a northern mixed-grass prairie ecosystem of eastern Montana, USA. During 2016-17, I conducted replicated point-count surveys at 150 locations on a 3,000-ha ranch managed with rest-rotation cattle grazing, and 155 locations on adjacent reference properties (4,300-ha) employing season-long or 2-pasture summer-rotational grazing systems to identify grazing management influences on grassland bird abundances. During 2016-17, I deployed remote cameras at 45 locations within rest-rotation grazing systems, and at 45 locations on reference properties to identity grazing management influences on mesocarnivore occupancy. Overall, there was no noticeable benefit of rest-rotation grazing on abundance or species diversity of grassland birds relative to season-long and summer-rotation grazing systems. Species-specific responses to livestock grazing system were found for each of three obligate grassland birds. Support for interactions between grazing system and local rangeland production potential were found, limiting the ability to recommend general livestock management practices for the benefit of grassland bird populations. Additionally, abundance of grasshopper sparrow (Ammodramus savannarum; beta = -0.10 + or = 0.03) and western meadowlark (Sturnella neglecta; beta = -0.09 + or = 0.03) showed a negative relationship with increasing stocking rate. Occupancy of mesocarnivores was highest in rest-rotation grazing systems, followed by season-long and summer-rotation systems, respectively, and showed a positive relationship with increasing stocking rate (beta = 1.64 + or = 1.10). Regional guidelines for livestock grazing management may be inappropriate in terms of grassland bird conservation efforts in the northern mixed-grass prairie.Item Range use and interspecific competition of Rocky Mountain bighorn sheep in the Highland Mountains, Montana(Montana State University - Bozeman, College of Letters & Science, 1994) Weigand, Joseph PaulItem Trends in size, land tenure, income, organization, and management of selected cattle ranches in southeastern Montana, 1924-48(Montana State University - Bozeman, College of Agriculture, 1949) Saunders, A. DaleItem Some size, income, and organization characteristics of the ranches of 46 Montana counties(Montana State University - Bozeman, College of Agriculture, 1938) Michaelsen, Leon C.Item Financial aspects of investment in livestock and pastures on irrigated farms(Montana State University - Bozeman, College of Agriculture, 1953) Reichel, John