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Item Evaluating habitat suitability for lesser prairie-chicken conservation in the mixed-grass prairie ecoregion(Montana State University - Bozeman, College of Agriculture, 2022) Solomon, Morgan Jean; Chairperson, Graduate Committee: Lance McNewPopulations of lesser prairie-chickens (Tympanuchus pallidicinctus; hereafter "prairie-chicken") in the southern Great Plains have declined by an estimated 85% and the species is currently being reconsidered for protections under the federal Endangered Species Act. Despite efforts to increase the quantity, quality, and connectivity of available habitat, prairie-chicken populations in the mixed-grass prairie ecoregion have remained relatively stable-to-declining. To provide information that will assist in providing more appropriate qualifications of available prairie-chicken habitat, I used ensemble modeling approaches and a least-cost path analysis to develop spatially-explicit predictions of prairie-chicken habitat and assess connectivity of identified habitat within the mixed-grass prairie ecoregion. In addition, I provided a critical comparison of the Western Association of Fish & Wildlife Agencies (WAFWA) Habitat Evaluation Guide and research-based field indices used to quantify the amount and quality of habitat for prairie-chicken conservation on a proprety participating in an incentive-based conservation program. I also explored the potential for using ecological site descriptions and relative condition (similarity index) to monitor reproductive habitat for prairie-chickens. Predictions from our ensembled model identified ~4,576 km 2 of potentially suitable prairie-chicken habitat both occupied and unoccupied. Least-cost path analyses revealed a low degree of connectivity between areas of occupied and unoccupied habitat indicating a low probability of natural recolonization. Managers should consider focusing conservation efforts on targeting habitat restoration between, within and around areas of identified occupied and unoccupied habitat. Habitat quality under the HEG habitat assessment protocol showed the property had excellent prairie-chicken habitat quality while research-based estimates showed the property only had marginal habitat quality for prairie-chickens. Differences in habitat quality assessments were in areas that had low percent cover of vegetation species preferred by prairie-chickens and in areas that had recently experienced fire. Thus, managers should consider using components of both habitat assessments protocols when quantifying habitat for prairie-chicken conservation to reduce the probability of producing erroneous estimates of habitat quality. Limited sample size within moderate categories of similarity index across ecological sites prevented us from reliably executing further analyses exploring the utility of using a similarity index as a tool for monitoring prairie-chicken habitat.Item Impacts of species protections on wind turbine development: evidence from golden eagle protection policies(Montana State University - Bozeman, College of Agriculture, 2023) O'Brien, Brock Daniel; Chairperson, Graduate Committee: Diane CharltonAs demand for wind energy grows, policymakers face tradeoffs between wind turbine development and wildlife species protections. This is particularly relevant for golden eagles, which have a habitat that overlaps areas of high wind energy development potential. Golden eagle protections, such as the Bald and Golden Eagle Protection Act (BGEPA), therefore potentially conflict with wind energy development goals. Policymakers face a lack of information regarding the existence and size of potential impacts of species protections on wind development. To approach this issue, I employ a difference-in-differences research design exploiting variation in BGEPA enforcement over time and geographic variation in golden eagle exposure to identify the impacts of species protections on wind development in resource-rich areas. I find that counties with high golden eagle exposure experienced declines in expected wind turbine capacity additions of 3.78 megawatts during the enforcement period, suggesting a total of 420 megawatts of foregone wind energy. This electricity generation loss has an estimated value of $56 to $142 million annually. Existing golden eagle valuation methods suggest significant economic gains from wind turbine expansion, although these estimations arguably apply only to marginal wildlife impacts and should be applied with caution. These results emphasize that the value of foregone renewable energy is an often-overlooked component of species protection policy discussions, and that effective conservation measures and funding are necessary both for the futures of many species and for renewable technology deployment.Item Habitat selection and movement behavior of Chiricahua leopard frogs(Montana State University - Bozeman, College of Letters & Science, 2015) Hinderer, Ross Kenneth; Chairperson, Graduate Committee: Andrea Litt; Andrea R. Litt, Magnus McCaffery and Robert A. Garrott were co-authors of the article, 'Dispersal of Chiricahua leopard frogs from perennial ponds' submitted to the journal 'Journal of herpetology' which is contained within this thesis.; Andrea R. Litt, Magnus McCaffery and Robert A. Garrott were co-authors of the article, 'Habitat selection by Chiricahua leopard frogs' submitted to the journal 'Journal of herpetology' which is contained within this thesis.Degradation of habitat and disruption of dispersal are major drivers of amphibian declines, including that of the Chiricahua leopard frog (Lithobates chiricahuensis). Currently, the Chiricahua leopard frog is federally threatened and restricted to anthropogenic sources of water, including ponds maintained for livestock, throughout much of its range. Habitat selection and patterns of dispersal between disjunct water sources are not well understood for this species. We captured frogs leaving ponds using pitfall traps and attached radio transmitters to frogs on the Ladder Ranch in southern New Mexico during summers 2013 and 2014. We checked pitfall traps and located telemetered frogs daily for up to 8 weeks. We assessed cues affecting the number of frogs emigrating from ponds using linear models, distances moved by frogs each day using linear mixed models, and finescale habitat selection using conditional logistic regression. Emigration of frogs from ponds was related to rainfall and was greatest at an intermediate level of rain. Daily movement distances were highly variable among individual frogs and not related to sex or size of the frog, which suggests that individual heterogeneity in dispersal behavior may be an adaptation of this species. We observed daily and total movement distances longer than any previously recorded for the species. Habitat selection was very consistent among individuals. Frogs chose habitats with more low-lying cover, a tree overstory, and a mud substrate, features created by summer monsoon rains. We suggest preservation and restoration of habitat features important for frogs and selecting translocation sites and times based on movement behavior observed in this study. Our findings will inform reintroductions of and habitat improvements for Chiricahua leopard frogs, with the eventual goal of delisting this species.Item The genesis of wildlife conservation in Montana(Montana State University - Bozeman, College of Letters & Science, 1987) Brownell, Joan LouiseItem Analysis of the listing of species as endangered or threatened under the Endangered Species Act(Montana State University - Bozeman, College of Letters & Science, 1993) Easter-Pilcher, Andrea L.Item Impacts of winter recreationists on wildlife in a portion of Yellowstone National Park, Wyoming(Montana State University - Bozeman, College of Letters & Science, 1981) Aune, KeithItem Glucocorticoid stress responses of lions in relation to group composition, human land use and proximity to people(2013-06) Creel, Scott; Christianson, David A.; Schuette, PaulLarge carnivore populations are in global decline, and conflicts between large carnivores and humans or their livestock contribute to low tolerance of large carnivores outside of protected areas. African lions (Panthera leo) are a conflict-prone species, and their continental range has declined by 75% in the face of human pressures. Nonetheless, large carnivore populations persist (or even grow) in some areas that are occupied by humans. Lions attain locally high density in the Olkiramatian and Shompole Group Ranches of Kenya's South Rift region, despite residence by pastoralist Maasai people and their sheep, goats, and cattle. We have previously found that these lions respond to seasonal movements of people by moving away from occupied settlements, shifting into denser habitats when people are nearby, and moving into a protected conservation area when people move into the adjacent buffer zone. Here, we examined lion stress responses to anthropogenic activities, using enzyme-linked immunoassay to measure the concentration of faecal glucocorticoid metabolites in 136 samples collected from five lion groups over 2 years. Faecal glucocorticoid metabolite concentrations were significantly lower for lions in the conservation area than for lions in the human-settled buffer zone, and decreased significantly with increasing distance to the nearest occupied human settlement. Faecal glucocorticoid metabolite concentrations were not detectably related to fine-scaled variation in prey or livestock density, and surprisingly, faecal glucocorticoid metabolite concentrations were higher in the wet season, when regional prey abundance was high. Lions coexist with people and livestock on this landscape by adjusting their movements, but they nonetheless mount an appreciable stress response when conditions do not allow them to maintain adequate separation. Thus, physiological data confirm inferences from prior data on lion movements and habitat use, showing that access to undisturbed and protected areas facilitates human–lion coexistence in a broader landscape that is used by people and livestock.Item Detecting declines of apex carnivores and evaluating their causes: An example with Zambian lions(Elsevier, 2014) Rosenblatt, Elias G.; Becker, Matthew S.; Creel, Scott; Droge, Egil; Mweetwa, Thandiwe; Schuette, Paul; Watson, Fred; Merkle, Johnathan; Mwape, HenryLarge carnivores are in rapid global decline, with a broad array of consequences for the ecosystems they inhabit. To efficiently detect and address these declines requires unbiased and precise demographic data. Unfortunately, the characteristics that make large carnivores extinction-prone also pose serious challenges to obtaining these data. Rapid survey methods exist, but provide only relative measures of abundance, cannot detect declines before they become large, and provide little or no information about the causes of decline. African lions (Panthera leo) are declining throughout their range, making accurate monitoring of remaining populations urgent. We provide statistically rigorous estimates of population size, trends, survival rate and age–sex structure from Zambia’s South Luangwa lion population from 2008 to 2012, just prior to cessation of hunting in 2013. Mark-recapture models fit to data from intensive monitoring of 210 individual lions in 18 prides and 14 male coalitions indicated a declining population, low recruitment, low sub-adult and adult male survival, depletion of adult males, and a senescing adult female population. Trophy hunting was the leading cause of death, with 46 males harvested. Based on these data we recommend continuing the hunting ban at least to 2016 to allow recovery, with substan-tially reduced quotas, age-limits, and effective trophy monitoring mandated thereafter should hunting resume. Similar data from intensive monitoring of key Zambian lion populations is required to evaluate effects of the hunting ban and provide management guidance. Effectively integrating intensive long-term monitoring and rapid survey methods should be a priority for future management and monitoring of carnivore species.Item Environmental correlates of temporary emigration for female Weddell seals and consequences for recruitment(Ecological Society of America, 2014) Stauffer, Glenn E.; Rotella, Jay J.; Garrott, Robert A.; Kendall, WilliamIn colonial-breeding species, prebreeders often emigrate temporarily from natal reproductive colonies then subsequently return for one or more years before producing young. Variation in attendance–nonattendance patterns can have implications for subsequent recruitment. We used open robust-design multistate models and 28 years of encounter data for prebreeding female Weddell seals (Leptonychotes weddellii [Lesson]) to evaluate hypotheses about (1) the relationships of temporary emigration (TE) probabilities to environmental and population size covariates and (2) motivations for attendance and consequences of nonattendance for subsequent probability of recruitment to the breeding population. TE probabilities were density dependent (ˆerrors of population size in the previous year) and increased when the fast-ice...Item Estimating nest abundance while accounting for time-to-event processes and imperfect detection(Ecological Society of America, 2014) Peron, Guillaume; Walker, Johann; Rotella, Jay J.; Hines, James; Nichols, JamesBirds and their population dynamics are often used to understand and document anthropogenic effects on biodiversity. Nest success is a critical component of the breeding output of birds in different environments; but to obtain the complete picture of how bird populations respond to perturbations, we also need an estimate of nest abundance or density. The problem is that raw counts generally underestimate actual nest numbers because detection is imperfect and because some nests may fail or fledge before being subjected to detection efforts. Here we develop a state-space superpopulation capture–recapture approach in which inference about detection probability is based on the age at first detection, as opposed to the sequence of re-detections in standard capture–recapture models. We apply the method to ducks in which (1) the age of the nests and their initiation dates can be determined upon detection and (2) the duration of the different stages of the breeding cycle is a priori known. We fit three model variants with or without assumptions about the phenology of nest initiation dates, and use simulations to evaluate the performance of the approach in challenging situations. In an application to Blue-winged Teal Anas discors breeding at study sites in North and South Dakota, USA, nesting stage (egg-laying or incubation) markedly influenced nest survival and detection probabilities. Two individual covariates, one binary covariate (presence of grazing cattle at the nest site), and one continuous covariate (Robel index of vegetation), had only weak effects. We estimated that 5–10% of the total number of nests were available for detection but were missed by field crews. An additional 6–15% were never available for detection. These percentages are expected to be larger in less intense, more typical sampling designs. User-friendly software nestAbund is provided to assist users in implementing the method.