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Item Population structure, gene flow, and genetic diversity of Rocky Mountain bighorn sheep informed by genomic analysis(Montana State University - Bozeman, College of Agriculture, 2020) Flesch, Elizabeth Pearl; Chairperson, Graduate Committee: Jennifer Thomson; Jay J. Rotella, Jennifer M. Thomson, Tabitha A. Graves and Robert A. Garrott were co-authors of the article, 'Evaluating sample size to estimate genetic management metrics in the genomics era' in the journal 'Molecular ecology resources ' which is contained within this dissertation.; Tabitha A. Graves, Jennifer M. Thomson, Kelly M. Proffitt, P.J. White, Thomas R. Stephenson and Robert A. Garrott were co-authors of the article, 'Evaluating wildlife translocations using genomics: a bighorn sheep case study' in the journal 'Ecology and evolution' which is contained within this dissertation.; Tabitha A. Graves, Jennifer M. Thomson, Kelly M. Proffitt and Robert A. Garrott were co-authors of the article, 'Genetic diversity of bighorn sheep population is associated with dispersal, augmentation, and bottlenecks' submitted to the journal 'Biological conservation' which is contained within this dissertation.This dissertation evaluated the genomics of bighorn sheep (Ovis canadensis) herds across the Rocky Mountain West to determine optimal sample size for estimating kinship within and between populations (Chapter Two), to detect gene flow due to natural dispersal and translocations (Chapter Three), and to evaluate the correlation between genetic diversity and influences on population size (Chapter Four). To date, wildlife managers have moved many bighorn sheep across the Rocky Mountain West in an effort to provide new genetic diversity to isolated herds. However, little is known about the genetics of these herds and the real impacts of translocations. To learn how populations have been impacted by these management actions, we genotyped 511 bighorn sheep from multiple populations using a new cutting-edge genomic research technique, the Illumina Ovine High Density array, which contained about 24,000 to 30,000 single nucleotide polymorphisms informative for Rocky Mountain bighorn sheep. First, we determined that a sample size of 20 to 25 bighorn sheep was adequate for assessment of intra- and interpopulation kinship. In addition, we concluded that a universal sample size rule for all wild populations or genetic marker types may not be able to sufficiently address the complexities that impact genomic kinship estimates. Secondly, we synthesized genomic evidence across multiple analyses to evaluate 24 different translocation events; we detected eight successful reintroductions and five successful augmentations. One native population founded most of the examined reintroduced herds, suggesting that environmental conditions did not need to match for populations to persist following reintroduction. Finally, we determined that influences on population size over time were correlated with genetic diversity. Gene flow variables, including unassisted connectivity and animals contributed in augmentations, were more important predictors than historic minimum population size and origin (i.e. native vs. reintroduced). This hypothesis-based research approach will give wildlife managers additional biological insight to help inform various management options for bighorn sheep restoration and conservation.Item Is habitat constraining bighorn sheep distribution and restoration: a case study in the Greater Yellowstone Ecosystem(Montana State University - Bozeman, College of Letters & Science, 2019) Lula, Ethan Shawn; Chairperson, Graduate Committee: Robert A. GarrottRocky Mountain Bighorn Sheep (Ovis canadensis) restoration continues to be a challenge throughout western North America despite nearly a century of efforts dedicated to the species' recovery. A persistent problem for restoration is populations failing to expand into surrounding areas of habitat even during years of population growth. While populations can be constrained by several environmental factors and behavioral tendencies, we contend habitat availability is not the primary limiting factor. This study incorporated GPS data from bighorn sheep within the Taylor-Hilgard population in the Madison Mountain Range, located in the northwestern extent of the Greater Yellowstone Ecosystem (GYE), to develop summer and winter resource selection function (RSF) habitat models. The objective of this study was to evaluate a hypothesis that habitat was not the primary factor limiting distributions of bighorn sheep within the Madison Range by developing biologically-plausible RSF models and using covariates expected to influence selection. Multiple functional forms and spatial grains for covariates were considered and sets of summer and winter resource selection models compared using AIC subscript c. Results indicated that bighorn sheep resource selection was grain dependent, with bighorn sheep generally selecting covariates at the larger 500 m and 1,000 m spatial grains. Summer selection was characterized by rugged terrain, steep slopes, reduced canopy cover, southwestern aspects and ridgelines. Winter selection was characterized by low elevations, southwestern aspects, steep slopes, reduced canopy cover, ridgelines, high summer NDVI amplitude, and areas close to steep terrain (slopes > or = 45°). Predicted winter habitat occurred in a non-contiguous distribution primarily along low-elevation, southwest-facing aspects within the Madison Valley, and predicted summer habitat was concentrated along high elevation ridgelines. Model results were successfully validated using independent GPS data. Potential abundance for the Madison Range was estimated by linking the winter RSF to population estimates for the Taylor Hilgard and results suggested that the Range may be capable of supporting 2 to 4 times the number of bighorn sheep currently estimated. Study results supported the hypothesis that habitat was not the primary factor limiting extant bighorn sheep populations, suggesting that broader distributions within the Range are possible if novel restoration strategies are considered.Item Spatial ecology of mountain ungulates in the northern Rocky Mountains: range expansion, habitat characteristics, niche overlap, and migratory diversity(Montana State University - Bozeman, College of Letters & Science, 2018) Lowrey, Blake Henson; Chairperson, Graduate Committee: Robert A. Garrott; Robert A. Garrott, Hollie M. Miyasaki, Gary Fralick and Sarah R. Dewey were co-authors of the article, 'Seasonal resource selection by introduced mountain goats in the southwest greater Yellowstone area' in the journal 'Ecosphere' which is contained within this thesis.; Robert A. Garrott, Doug E. McWhirter, P.J. White, Nicholas J. DeCesare and Shawn T. Stewart were co-authors of the article, 'Niche similarities among introduced and native mountain ungulates' in the journal 'Ecological applications' which is contained within this thesis.; Kelly M. Proffitt, Douglas E. McWhirter, P. J. White, Alyson B. Courtemanch, Sarah R. Dewey, Hollie M. Miyasaki, Kevin L. Monteith, Julie S. Mao, Jamin L. Grigg, Carson J. Butler, Ethan S. Lula and Robert A. Garrott were co-authors of the article, 'Contrasting seasonal movements in native and restored populations: a case for conserving migratory portfolios' submitted to the journal 'Journal of applied ecology' which is contained within this thesis.; Douglas E. McWhirter, Kelly M. Proffitt, Alyson B. Courtemanch, Kevin L. Monteith, P. J. White, J. Terrill Paterson, Sarah R. Dewey and Robert A. Garrott were co-authors of the article, 'Individual variation creates diverse portfolios of seasonal movement patterns and ranges in a migratory ungulate' submitted to the journal 'Ecology' which is contained within this thesis.Mountain ungulates, although recognized as iconic and charismatic wildlife species, are the least studied and understood large mammals in western North America. The paucity of data, specifically concerning spatial ecology, presents a formidable challenge to regional wildlife managers tasked with the responsibility of managing populations with limited empirical studies on which to base decisions. We used GPS data collected from bighorn sheep (Ovis canadensis) and mountain goats (Oreamnos americanus) sampled from multiple populations throughout the northern Rocky Mountains to develop comparative studies characterizing seasonal habitats and potential range expansion of introduced mountain goats, niche overlap with native bighorn sheep, and migratory diversity of restored, augmented, and native bighorn sheep. Slope was the dominant predictor of mountain goat habitat use in both seasons, although mountain goats selected for steeper slopes in winter than in summer. Regional extrapolations depicted suitable mountain goat habitat in the Snake River, Teton, Gros Ventre, Wyoming and Salt Ranges centered around steep and rugged areas. Although bighorn sheep occurred on steeper slopes than mountain goats in summer and mountain goats occurred on steeper slopes in winter, we observed broad niche overlap according to season-species niche models and observed GPS locations where the two species were sympatric. In native bighorn sheep herds, we observed longer migrations on average and significantly more variation among individuals when compared to restored herds. The enhanced individual variation in native herds resulted in diverse portfolios of migratory behaviors and ranges, including newly documented high elevation long-distance migrants, increased switching rates between migratory behaviors, and sub-populations that were diffusely spread across both summer and winter ranges. In contrast, restored herds had limited individual variation, were largely non-migratory, had less switching between years, and were generally concentrated on both summer and winter ranges. In addition to increasing the abundance and distribution of bighorn sheep on the landscape, we suggest there may be value in simultaneously increasing the diversity of seasonal movement strategies, and in so doing, building resilience to future perturbations and disease, and mirroring the movement portfolios observed in native populations of bighorn sheep.Item Assessing respiratory pathogen communities and demographic performance of bighorn sheep populations: a framework to develop management strategies for respiratory disease(Montana State University - Bozeman, College of Letters & Science, 2017) Butler, Carson Joseph; Chairperson, Graduate Committee: Robert A. GarrottRespiratory disease (pneumonia) is a persistent challenge for bighorn sheep (Ovis canadensis) conservation as sporadic epizootics cause up to 90% mortality in affected populations and are often followed by numerous years of low juvenile recruitment attributed to lamb pneumonia. Domestic sheep (Ovis aries) and domestic goats (Capra aegagrus hircus) are the origin of the disease and asymptomatically carry respiratory pathogens that cause respiratory disease when introduced to bighorn sheep. Pathogens that have been linked to respiratory disease in bighorn sheep include several species of bacteria in the Pasteurellaceae family and another bacterial species, Mycoplasma ovipneumoniae. Despite substantial efforts by management agencies to prevent contact between bighorn sheep and domestic sheep and goats, respiratory disease epizootics continue to affect bighorn sheep populations across much of their distribution with uncertain etiology. This study sought to investigate efficacy of diagnostic protocols in detecting Pasteurellaceae and Mycoplasma ovipneumoniae and generate sampling recommendations for different protocols, assess the distribution of these disease agents among 17 bighorn sheep populations in Montana and Wyoming and evaluate what associations existed between detection of these agents and demographic performance of bighorn sheep populations. Analysis of replicate samples from individual bighorn sheep revealed that detection probability for regularly-used diagnostic protocols was generally low (<50%) for Pasteurellaceae and was high (>70%) for Mycoplasma ovipneumoniae, suggesting that routine pathogen sampling likely mischaracterizes respiratory pathogen communities. Power analyses found that most pathogen species could be detected with 80% confidence at the population-level by conducting regularly-used protocols multiple times per animal. Each pathogen species was detected in over half of the study populations, and consideration of detection probability discerned that there was low confidence in negative test results for populations where the Pasteurellaceae species were not detected. 76% of study populations hosted Mycoplasma ovipneumoniae and Pasteurellaceae pathogens, yet a number of these populations were estimated to have positive population growth rates and recruitment rates greater than 30%. Overall, the results of this work suggest that bighorn sheep respiratory disease may be mitigated by manipulating population characteristics and respiratory disease epizootics could be caused by pathogens already resident in bighorn sheep populations.Item A metabolomics approach for the study of long-term progesterone in domestic sheep and physiological processes in domestic and bighorn sheep(Montana State University - Bozeman, College of Agriculture, 2017) Herrygers, Melissa Rashelle; Chairperson, Graduate Committee: James G. Berardinelli; J. M. Thomson, K. A. Perz, K. B. Herrygers and J. G. Berardinelli were co-authors of the article, 'Effect of long-term progesterone on feed efficiency, body compostition, non-esterified fatty acids, and metabolic hormones in mature Rambouillet ewes' submitted to the journal 'Journal of animal science' which is contained within this thesis.; J. M. Thomson, K. A. Perz, K. B. Herrygers, V. Copie, B. Tripet, and J. G. Berardinelli were co-authors of the article, 'Using nuclear magnetic resonance spectroscopy (NMR) metabolic profiling to study the effect of long-term progesterone on metabolic profiles in Rambouillet ewes' submitted to the journal 'Journal of metabolomics' which is contained within this thesis.; J. White, C. Butler, R.A. Garrott, V. Copie, B. Tripet, and J. G. Berardinelli were co-authors of the article, 'Potential identification of metabolic biomarkers using nuclear magnetic resonance spectroscopy (NMR) metabolic profiling for nutrition status, season, and location of bighorn sheep (Ovis canadensis) in Montana and Wyoming' submitted to the journal 'Journal of metabolomics' which is contained within this thesis.Metabolomics allows for a snapshot of global metabolisms by studying metabolic intermediates and products of cellular metabolism. Experiments 1 and 2's objectives were to evaluate the effects of long-term P4 treatment, independent of the influence of the placenta and fetus, on changes in feed efficiency, BW, body composition, NEFA, metabolic hormones, and metabolites identified through nuclear magnetic resonance (NMR) metabolic profiling in mature Rambouillet ewes. Thirty, multiparous, 5- and 6-yr-old Rambouillet ewes were stratified by age and metabolic BW and assigned randomly to receive long-term P4 administration using controlled intravaginal releasing devices (CIDR) or no P4 (CIDRX; CIDR backbone only). Sera samples and body weights were collected every 14-d, along with CIDR/CIDRX replacement. Sera samples were assayed for metabolic hormones, NEFA, and metabolites. There were no differences in BW, RFI, STDMI, body composition, or temporal patterns of T3, T4, NEFA, or metabolites between CIDR- and CIDRX-treated ewes. Insulin concentrations were greater in CIDR-treated ewes than in CIDRX-treated ewes. Long-term P4 did not affect metabolism or body composition, independent from the presence of a fetus or placenta. Progesterone may increase tissue sensitivity to INS. In Experiment 3, the primary aim was to determine if NMR metabolic profiling has the potential to serve as a management tool for evaluating herds of bighorn (Ovis canadensis) sheep. Bighorn sheep herds were sampled between December of 2014 to March of 2015 in Montana and Wyoming. The sampling included 240 bighorn sheep ewes from 13 herds from geographically distinct locations at different times of the year. Metabolites identified by NMR in bighorn sheep serum were analyzed by pathway enrichment analyses, PLS-DAs, and biomarker analyses to determine if bighorn sheep herds can be distinguished by pregnancy status, geographic location, or time of year. NMR metabolic profiling could not distinguish between pregnant and non-pregnant bighorn sheep. Metabolic profiling did differentiate bighorn sheep herds and identified a subset of potential biomarkers that discriminated distinct geographic locations and time of year. Thus, NMR metabolic profiling has the potential to develop a suite of metabolites that wildlife managers can use to assess bighorn sheep nutrition and overall health.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 Seasonal movements and habitat use of the Highland/Pioneer Mountains bighorn sheep herd of southwest Montana(Montana State University - Bozeman, College of Letters & Science, 1996) Semmens, William J.Item Ecology of bighorn sheep in the Sun River area of Montana during fall and spring(Montana State University - Bozeman, College of Letters & Science, 1974) Frisina, Michael R.Item Population dynamics of bighorn sheep on the Beartooth Wildlife Area, Montana(Montana State University - Bozeman, College of Letters & Science, 1999) Enk, Terrence A.Item Seasonal locations of bighorn sheep, mountain goats, and elk on the Haystack Domestic Sheep Allotment, Montana(Montana State University - Bozeman, College of Agriculture, 1993) Byelich, Boyd Raldon
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