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Item Movement ecology of female sage-grouse informs space use, resource selection, and demography in southern Valley County, MT(Montana State University - Bozeman, College of Agriculture, 2023) Haynam, Robert Thomas, III; Chairperson, Graduate Committee: Lance McNew; This is a manuscript style paper that includes co-authored chapters.The greater sage-grouse (Centrocercus urophasianus) is a focal species in the effort to conserve imperiled sagebrush ecosystems and associated organisms. Sage-grouse uses of landscapes are modulated by their multilevel movement processes. Understanding the relative contributions of hard-wired and environmental influences on movement processes is necessary for a comprehensive understanding of sage-grouse ecology. Correlates between fitness components and measurable landscape conditions may be of limited value if other influences such as sage-grouse movement and behavior are not accounted for. Movement behaviors may be risky in certain contexts and adaptive in other contexts, and differences in the characteristics of movement and therefore space-use among individuals can have implications for survival and reproductive performance. We collected detailed records of sage-grouse movements for up to 4 years per individual to investigate daily behavioral strategies of sage-grouse and therefore mechanisms driving habitat use and individual performance. During April-May, 2018-2019, we captured 86 (45 in 2018, 41 in 2019) female sage-grouse and outfitted them with GPS transmitters. We collected 192,640 geographic coordinates of 86 female sage-grouse during 2018-04-24 - 2022-04-14 which encompassed 4 complete annual cycles of sage-grouse. We confirmed 185 nest attempts of 76 individuals during the nesting seasons of 2018-2021. Hard-wired or learned seasonal behavior modes appeared to be more influential than vegetation conditions. Sage-grouse can exhibit reactive responses to landscape conditions but also use the landscape as a function of high-level endogenous constraints likely due to memory mechanisms, high temporal predictability of some resources, and moderate spatial heterogeneity of resources. Management prescriptions may ignore important ecological levels such as those responsible for learned-heuristic movement and space use modes. Relationship and magnitude of associations among sage-grouse use-intensity and landscape conditions varied among 7 behavior modes which indicates that behavioral and temporal context is important for understanding habitat and space use by sage-grouse. Our findings also support a fundamental demographic importance of area affinity, fidelity, and familiarity to sage-grouse ecology which has been overlooked in most research on sage-grouse or other birds.Item Risk effects in Elk (Cervus elaphus) : behavioral and nutritional responses to wolves and environmental conditions(Montana State University - Bozeman, College of Agriculture, 2008) Christianson, David Alan; Chairperson, Graduate Committee: Scott Creel.Until recently, predators have been though to regulate prey primarily through direct predation, in ecosystems where top down effects have been shown to be important. However, experiments and recent empirical observations show that the costs of antipredator responses in individuals that successfully avoid predation can exert equal or larger driving forces on population dynamics than the numerical effect of direct predation. Such a mechanism has not been explored in a large terrestrial vertebrate. I explored the antipredator responses of elk (Cervus elaphus) to wolves (Canis lupus) in the Upper Gallatin Canyon of southwest Montana, USA, December through May in the winters of 2003-2006. First I reviewed elk winter diet studies to understand what drives elk foraging behavior. Next I modeled the consequences of diet shifts in grazing and browsing on mass dynamics in wintering female elk. I also developed a new nutritional index, fecal chlorophyll, that I used primarily between winter and spring periods of nutrition as foraging constraints (and costs of antipredator response) would be quite different between these two periods. Specifically, I measured foraging behavior, diet selection, and nutrient balance in wintering elk and monitored daily predation risk as wolves moved naturally, in and out of four creek drainages that formed the primary winter range. Elk showed great sensitivity to fine-scale descriptions of wolf predation risk in nearly every response variable. In particular, adult female elk increased browsing on woody stems, sagebrush, and confers while adult males showed the opposition response and increased grazing on days when wolves were present in the same drainage. This work implies that predator may in fact play a large role in ecosystems including ecosystems where predators were deemed non-influential and bottom up effects important.