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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 Nest site taphonomy of modern archosaurs(Montana State University - Bozeman, College of Letters & Science, 2016) Ferguson, Ashley Lynn; Chairperson, Graduate Committee: David Varricchio; David J. Varricchio, Carlos I. Piña and Frankie D. Jackson were co-authors of the article, 'From eggs to hatchlings: nest site taphonomy of American crocodile (Crocodylus acutus) and broad snouted caiman (Caiman latirostris)' submitted to the journal 'Palaios' which is contained within this thesis.; David J. Varricchio and Alex J. Ferguson were co-authors of the article, 'Nest site taphonomy of colonial ground nesting birds at Bowdoin National Wildlife Refuge' submitted to the journal 'Palaios' which is contained within this thesis.The goal of this thesis is to investigate the taphonomic processes that affect crocodylian and modern bird nesting localities in the hope that they would shed light into the identification of fossil nesting grounds and the interpretation of juvenile developmental stage. This project in particular observed nests of American crocodiles (Crocodylus acutus) at the Turkey Point Power Plant in Homestead, Florida, broad snouted caiman (Caiman latirostris) nests in the Northern Santa Fe and Chaco Provinces of Argentina, and colonial ground nesting birds (American white pelicans, double-crested cormorants, ring-billed and California gulls) at Bowdoin National Wildlife Refuge (BNWR) east of Malta, Montana. A major component of this project is the documentation of potentially preservable components, i.e., specimens (bones, eggshell, etc.) and structures (e.g. nesting traces) that might be represented in the fossil record. This thesis documents the agents and processes influencing bone and egg accumulations and nesting trace preservation across diverse biologies and environments.Item An investigation of factors that may affect nest success in CRP lands and other grassland habitats in an agricultural landscape(Montana State University - Bozeman, College of Letters & Science, 1996) Clawson, Mark R.Item Inventory and monitoring of biodiversity : an assessment of methods and a case study of Glacier National Park, MT(Montana State University - Bozeman, College of Letters & Science, 1991) Debinski, Diane MarieBiodiversity is currently threatened around the world, yet humankind knows little about its distribution or rates of loss. Because biodiversity can be defined at the level of species, habitats, or genes, temporal changes can be assessed at several different levels. These changes may indicate responses to natural disturbances, human-induced changes, or long-term environmental trends. However, no standard analysis techniques for biodiversity assessment have yet been developed. In order to protect biodiversity or to use it as an indicator of environmental change, baseline data must be collected and analysis techniques must be developed. This research applies and evaluates sampling and analysis techniques for inventory and monitoring of biodiversity. Glacier National Park is used as a case study. Birds and butterflies were chosen to demonstrate species diversity inventory. The butterfly, Euphydryas gillettii, was used to demonstrate genetic diversity assessment. Biodiversity assessment sites were established throughout a range of habitats and monitored during the summers of 1987, 1988 and 1989. Thirty-three sites were monitored for birds and twenty-four sites were monitored for butterflies. Presence/absence sampling was used to classify species commonness and rarity. Goals accomplished included 1) describing the current species composition, 2) identifying diversity hotspots and sites supporting rare species, and 3) creating a baseline for assessing change. A discourse on biodiversity assessment would not be complete, however, without addressing the problems inherent in biodiversity assessment and management. Replication in both time and space is necessary to distinguish natural background variation in species distribution from true changes and sampling artifact. It is often difficult to reconcile the need for sampling replication within a habitat type with the need to survey a large, highly diverse ecosystem. Further, it is extremely difficult to use biodiversity as an environmental indicator unless relationships between species and environmental changes are specific and well-understood. Finally, management for biodiversity requires a large-scale perspective on ecosystem management and a modest understanding of the natural history of the species examined. Unless biodiversity assessments are done thoroughly and carefully, they will have limited descriptive or predictive value.Item Effects of ecological changes induced by various sagebrush control techniques on non-game birds(Montana State University - Bozeman, College of Letters & Science, 1970) Best, Louis BrownItem Indirect effects of herbicides on an agroecological trophic system(Montana State University - Bozeman, College of Agriculture, 2001) Taylor, Rebecca LynnItem Reproductive success and post-fledging behavior of red-tailed hawks (Buteo jamiacensis) in the Gallatin Valley, Montana(Montana State University - Bozeman, College of Agriculture, 1973) Johnson, Sara JaneItem An inventory of the bird populations within the Sarpy Creek drainage, southeastern Montana(Montana State University - Bozeman, College of Letters & Science, 1977) Herbert, JeffItem Breeding bird communities in mature and old-growth Douglas-fir forests in southwest Montana(Montana State University - Bozeman, College of Letters & Science, 1997) Sparks, James RobertItem Ecology of the breeding bald eagle and osprey in the Grand Teton-Yellowstone National Parks complex(Montana State University - Bozeman, College of Letters & Science, 1980) Alt, Kurt Langdon
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