Dissertations / Theses on the topic 'Centrocercus urophasianus'

Greater sage-grouse (Centrocercus urophasianus) habitat was studied in central Montana primarily on Wyoming big sagebrush (Artemisia tridentata wyomingensis) dominated rangeland. The primary objective was to compare shrub and herbaceous parameters within (use, random or non-use) and between seasonal habitats (nest, brood, winter). Nesting occurred in areas with greater total shrub cover (15v13%) and height (28v26 cm), and taller live (12v11 cm) and residual grass (9v8 cm) than randomly available. The shrubs under which hens nested were taller (50v44 cm) and more productive (61v51 g) than random shrubs. Due to increased precipitation in 2005, total herbaceous (18v13%), grass (15v12%), and forb cover (7v3%), and live grass height (13v10 cm) were greater in 2005 than 2004. Brood and paired random sites were similar for all parameters. There was greater shrub height (29v25 cm), total herbaceous cover (19v16%), forb cover (15v13%), and live grass height (17v11 cm) in 2005 than 2004. Shrub density (1.5v1.1/m²) and residual grass height (9v5 cm) were greater in 2004. Both winters were mild as no month had > 20 cm total snowfall. Shrub height was greater at winter non-use sites than use sites in 2005 (36v32 cm), but similar in 2004 (27v27 cm). Shrub height was different between years. Despite mild winters, shrub cover (12v10%) and density (1.2v0.8/m²) were greater at winter use sites than non-use sites although residual grass height (19v18 cm) and cover (13v14%) were similar. Winter use sites had less shrub cover than nest sites (12v15%). The nest and brood habitat and winter and brood habitat had similar shrub cover, density, and height. Herbaceous vegetation was more important during nesting and brood rearing than in winter. Some portions of grouse habitat may benefit from management for greater herbaceous cover, but never at the sake of less sagebrush. Sagebrush cover from 5 to 36% was the most consistent component of sage-grouse habitat. The differences between cover for nesting (15%), brood (14%), and winter (12%) were small. Therefore, any manipulation attempting to improve one seasonal habitat would impact the others.

Greater sage-grouse (Centrocercus urophasianus) adult and juvenile survival have been identified as critical demographic parameters. However, little is known regarding the dynamics of juvenile sage-grouse. From 2008-2010, I used radio-telemetry and 2 transmitter types to monitor 91 juvenile sage-grouse. Program MARK was used to analyze survival data. Over-winter survival was 0.802 - 0.982 and 0.687 - 0.969 for females and males, respectively. Fall survival rates were 0.522 - 0.623 for females and 0.332 - 0.449 for males. Survival from fall through winter was 0.418 - 0.616 for females and 0.228 - 0.435 for males. For both years combined, the probability predation caused death was 0.705, and probability harvest caused death was 0.159. The probability unreported harvest caused death was 0.091. Sex (p= 0.103) and transmitter type (p = 0.09) affected survival. Back-mounted transmitters negatively affected survival and their use should be avoided to minimize experimental bias.

Nesting and brood-rearing habitat data for greater sage-grouse (Centrocercus urophasianus) near Roundup in central Montana in 2004, Decker in south-central Montana and northern Wyoming in 2003, and Malta in north-central Montana in 2003 was collected. Sage-grouse hens were fitted with radio collars and tracked to nests. Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young) canopy cover, density, and height for nest vs. random sites and brood vs. random sites were compared to determine if hens were selecting for these parameters. Forb, grass, total herbaceous, and residual cover, grass height, and residual height were also compared. Nest sites near Roundup (53 nest sites), Decker (58), and Malta (45) were measured. Most nest sites near Roundup were in sagebrush (91 %). All nest sites near Decker and Malta were in sagebrush. Only nest sites in sagebrush habitats were analyzed. Nest sites had taller (48 vs. 42 cm, P ≤ 0.01) and more productive (60 vs. 46 g of produced forage, P ≤ 0.01) nest shrubs than random sites near Roundup. At the Decker study area, nest sites had greater sagebrush cover (22 vs. 14 %, P ≤ 0.01), density (1.1 vs. 0.6 shrubs per m2, P ≤ 0.01), and taller shrubs within 15 m (52 vs. 42 cm, P ≤ 0.01) than random sites. Nest sites had taller shrubs within 15 m of the nest (30 vs. 26 cm, P ≤ 0.05) near Malta. Successful and failed nest sites did not differ between the Roundup and Decker study areas. Yearling nest sites had shorter grass than adult sites in Roundup (9 vs. 11 cm, P ≤ 0.05). Forty-four brood sites near Roundup and 73 brood sites near Decker were measured. Brood sites were not measured near Malta. Most brood sites near Roundup (71 %) and all near Decker (100 %) were in sagebrush. Only brood sites in sagebrush habitats were analyzed. Vegetation was similar between brood and paired random sites near Roundup. At the Decker study area, brood sites had denser sagebrush (1.1 vs. 0.6 shrubs per m2, P ≤ 0.01) than random sites. Adult and yearling hen brood sites did not differ near Roundup. Adult brood sites had greater sagebrush cover (14 vs. 8 %, P ≤ 0.05), density (1.0 vs. 0.6 shrubs per m2, P ≤ 0.05), and taller shrubs within 15 m (44 vs. 37 cm, P ≤ 0.05) than yearling sites near Decker. Brood sites had less shrub cover at 4 weeks than weeks 1 and 2 (10 vs. 16 and 17 %, P ≤ 0.01) near Roundup. Sagebrush habitats comprised 97 % (151 of 156) of the total nest sites and 92 % (108 of 117) of all brood locations. Nest sites had 19-22 % sagebrush cover, 26-52 cm sagebrush heights, and total herbaceous cover of 13-33 %. Brood sites had 12-13 % sagebrush cover, 22-43 sagebrush heights, and 14-33 % total herbaceous cover. This study reinforces the importance of sagebrush habitats for nesting and brood-rearing sage-grouse. Management practices which remove this shrub would probably reduce the nesting and brood-rearing success of sage-grouse in central Montana and northern Wyoming.

Noise associated with human activity is widespread and expanding rapidly in terrestrial environments, but there is still much to learn about its effects on animals. To determine the effect of introduced noise on lek attendance and strutting behavior, I played back recorded continuous and intermittent anthropogenic sounds associated with natural gas drilling and roads at leks of Greater Sage-Grouse (Centrocercus urophasianus). For 3 breeding seasons, I monitored sage-grouse abundance at leks with and without noise. Peak male attendance (i.e., abundance) at leks experimentally treated with noise from natural gas drilling and roads decreased 29% and 73% respectively relative to paired controls. Decreases in abundance at leks treated with noise occurred in the first year of the study and were sustained throughout the experiment. There was limited evidence for an effect of noise playback on peak female attendance during the experiment or on male attendance the year after the experiment ended. These results suggest that sage-grouse avoid leks with anthropogenic noise and that intermittent noise has a greater effect on attendance than continuous noise. To quantify the potential for noise from natural gas infrastructure to mask sage-grouse vocalizations over both long and short distances, I analyzed both the individual notes of mating vocalizations produced by male sage-grouse and recordings of such noise. Noise produced by natural gas infrastructure is predicted to mask sage-grouse vocalizations substantially, reducing the active space of detection and discrimination of all vocalization components, particularly impacting notes that are low frequency and low amplitude. Such masking could increase the difficulty of mate assessment for lekking sage-grouse. Significant impacts to sage-grouse populations have been measured at noise levels that predict little to no masking. I investigated whether male sage-grouse adjust the repetition and timing of their strut displays in response to playback of noise associated with natural gas development. I compared the signaling behavior of male sage-grouse on leks with long-term drilling and road noise playback to that of males on similar leks with no noise playback. Males exposed to long-term drilling noise playback strutted at higher rates and in longer bouts than males on control leks, while males on road noise leks strutted at lower rates and in shorter bouts than males on control leks; these differences were only observed during close courtship, when strut rate is most important in influencing female mate choice. I did a short-term playback of intermittent traffic noise and compared the strut timing of individuals during noisy and quiet periods. Males performed fewer struts overall during noisy periods, but male strutting behavior was related to female proximity. Males that were not closely approached by females strutted less during noisy periods than quiet periods and males that engaged in close courtship with females strutted at similar rates during noisy and quiet periods, even when females were far away. Introduced noise associated with natural gas development causes large declines in sage-grouse lek attendance and is likely to cause substantial masking of sage-grouse vocalizations. However, masking is not likely to be the only mechanism of noise impact on this species. Sage-grouse may at least partially reduce masking impacts through behavioral plasticity, adjusting the timing of their signals in a manner that may reduce the impacts of masking on communication.

Greater sage-grouse populations have decreased steadily since European settlement in western North America. Reduced availability of brood-rearing habitat has been identified as a limiting factor for many populations. We used radio-telemetry to acquire locations of sage-grouse broods from 1998 to 2012 in Strawberry Valley, Utah. Using these locations and remotely-sensed imagery, we proceeded to 1) determine which features of brood-rearing habitat could be identified using widely available, fine-scale imagery 2) assess the scale at which sage-grouse selected brood-rearing habitat in our study area, and 3) create a predictive habitat model that could be applied across our large study area to identify areas of preferred brood-rearing habitat. We used AIC model selection to evaluate support for a list of variables derived from remotely-sensed imagery. We examined the relationship of explanatory variables at three scales (45, 200, and 795 meter radii). Our top model included 10 variables (percent shrub, percent grass, percent tree, percent paved road, percent riparian, meters of sage/tree edge, meters of riparian/tree edge, distance to tree, distance to transmission lines, and distance to permanent structures). Variables from each scale were represented in our top model with the majority of scale-sensitive variables suggesting selection at the larger (795 meter) scale. When applied to our study area our top model predicted 75% of naive brood locations suggesting reasonable success using this method and widely available NAIP (National Agricultural Imagery Program) imagery. We encourage application of this method to other sage-grouse populations and species of conservation concern. The northern river otter is a cryptic semi-aquatic predator that establishes and uses latrines. Highly used river otter latrines indicate otter "activity centers" since frequency of scat deposition is thought to be correlated to frequency of habitat use. We compared an indirect method (scat counts) and a direct method (remote cameras) of determining latrine utilization in order to assess the accuracy of the commonly used indirect method. To further compare these methods we used them to examine effects of anthropogenic disturbance on otters of the Provo River in Utah. We found that overall the direct and indirect methods were highly correlated. There was significant seasonal variation in the degree of correlation between the indirect and direct methods with correlation being significantly higher in the summer. We found similar results when using these methods to examine effects of anthropogenic disturbance. For each method the distance of the latrine to trails was significant in one of the top competing models. We suggest that space use of otters in our study area is being affected by anthropogenic disturbance as measured by distance to trails. We also suggest that scat counts should only be conducted during the summer when they correlate best with actual levels of otter activity.

The decline of greater sage-grouse (Centrocercus urophasianus) populations across western North America has intensified conservation, research, and management efforts. Predator-prey interactions have been the focus of widespread scientific study, but little research has been conducted on the effects of predation and predator removal on sage-grouse ecology. This study had three main objectives: 1) identify the types of predators impacting hen survival and nest success, 2) compare the effect of predator removal on vital rates, and 3) evaluate habitat selection and movement. Over two years (2011-2012), an observational study and field experiment were used to test the effects of predation and predator removal on sage-grouse survival, nest success, and spatial ecology in Bighorn Basin, Wyoming. In year one, I quantified the impacts of predators on sage-grouse demographics and developed a basis for monitoring sage-grouse and predator populations. In year two, predator removal was modified to remove the primary nest and hen predator in this system: coyote (Canis latrans). I evaluated the impact of anthropogenic features and management on sage-grouse home range size, seasonal movement, and habitat selection for potential behavioral responses. Resource selection functions (RSFs) were used to determine habitat selection and identify differences at multiple spatial extents (seasonal and annual scales). Hen survival was improved in sites treated with coyote removal over the nesting period (P = 0.05) but no improvement was seen in annual hen survival (P = 0.19). Observed nest success was higher at the site without coyote removal (P < 0.0001). RSF modeling showed sage-grouse to be sensitive to predator removal, avoiding areas close to roads, with high well density, and steep slopes. While this study suggests predator removal does not benefit observed nest success, provides only short-term enhancement to survival, and may disrupt habitat selection, potentially benefits to other life stages could exist and be detected with more time and monitoring. By taking an experimental approach to examining the effects of predation and predator removal, this study advances our knowledge of sage-grouse ecology by identifying changes in demographic vital rates and habitat selection, propagating the best management possible for sage-grouse populations.

Greater sage-grouse (Centrocercus urophasianus; sage-grouse) are sagebrush obligates and are therefore considered to be key indicators of sagebrush ecosystem health. Sage-grouse populations have declined range-wide over the last century due to loss and fragmentation of sagebrush (Artemisia spp.) habitats. Sage-grouse populations found in large intact sagebrush landscapes are considered to be more resilient, however, some small isolated populations persist and thrive in fragmented landscapes. Because of Utah’s unique topography and geography, sage-grouse habitat is discontinuous and populations are naturally dispersed throughout the state in suitable intact blocks or in disconnected islands of sagebrush habitat. Thus, Utah populations provide the ideal place to understand how landscape attributes may influence at risk populations. Of these, the Morgan-Summit population is important because very little was known about the general ecology of this population and it experiences a high level of anthropogenic disturbances. I examined seasonal movement patterns, habitat selection, vital rates (nest initiation rates, nest success, clutch size, breeding success, brood success, and survival probability of breeding age birds) and the influence of vegetation components on vital rates of a small geographically isolated sage-grouse population in Morgan and Summit Counties in northern Utah from 2015–2016. To collect the data, I deployed 25 very-high frequency radio collars and 10 platform terminal transmitters and completed micro-site vegetation surveys at nest, brood, and paired random sites and then made comparisons. Nest sites exhibited variation in vegetation structure that influenced nest success, while brood sites did not. This population is one of the most productive in Utah exhibiting high nest initiation rates, hatching rates, and brood success rates despite limited habitat space and small seasonal movements. Transmitter type had no influence on vital rates, which is contrary to other studies, and limited influence on habitat selection. Sage-grouse avoided trees and developed areas, especially during the breeding season. Selection of other landscape variables was season-dependent. This information suggests that a sage-grouse population can occupy areas of limited habitat on an annual basis if seasonal habitat requirements are met. This study provides information that stake holders can utilize to conserve critical seasonal habitats within this study area where the population could be negatively affected by anthropogenic development pressure.

Concern regarding the effect of energy development on greater sage-grouse (Centrocercus urophasianus) is increasing as the search for fossil fuel intensifies. Sage-grouse may be especially sensitive to energy development because they require large, diverse areas of sagebrush (Artemisia spp.) habitat to complete their life cycle. Additionally, the network of pipelines, roads, and wells required by energy development may fragment sagebrush habitat isolating populations and contributing to genetic drift, inbreeding, local extinction, or rapid divergence. Seep Ridge, located in northeastern Utah, is one area where sage-grouse habitat and energy development plans overlap. Approved leases call for the construction of an additional 4,000 natural gas wells in an area currently occupied by a small sage-grouse population. This research was completed to 1) collect baseline data on the survival, reproductive success and habitat use of the Seep Ridge sage-grouse population, 2) examine sage-grouse habitat use patterns in relation to development, and 3) describe sage-grouse mitochondrial genetic diversity in 3 northeastern Utah populations relative to other parts of the species range. I captured and monitored 16 sage-grouse from the Seep Ridge population in 2007 and 2008. Adult mortality rate of the Seep Ridge population was high (65.2%) and recruitment was low (7.1%) compared to other sage-grouse populations in Utah. Additionally, the monitored sage-grouse used habitats located farther from wells more frequently than habitat located near wells, relative to well spacing. Current habitats occupied by this population do not meet recommended guidelines. No unusual haplotype compositions were observed in the genetic survey of the northeastern Utah sage-grouse populations. However, differences in haplotype composition between the Anthro Mountain and Strawberry Valley populations and other northeastern grouse populations indicate there may be a barrier to gene flow in the area. I also documented that the Seep Ridge population is connected to another population inhabiting Ute Tribal land. This observation suggests that the populations inhabiting Ute Tribal land may constitute a source population to recolonize Seep Ridge during the post-energy development periods. I recommend that mitigation measures incorporate restricting development in breeding habitat, maintaining connections between populations, and actions to reduce adult mortality on the summer range. I also recommend that biologists continue collecting genetic samples from northeastern Utah sage-grouse populations to understand population structure, divergent evolution, and inform decisions concerning translocation

My research focused on common raven (Corvus corax; hereafter raven) winter ecology and removal, and how raven removal aids Greater sage-grouse (Centrocerus urophasiansu; hereafter sage-grouse) populations. Raven winter ecology in the western US has not been described in detail. I researched raven use of landfills for foraging and raven use of anthropogenic structures for roosting, as well as dispersal of ravens in the spring. In all 22% of radio-marked ravens (n=73) used landfills during the day, and 68%(n=73) roosted at anthropogenic roost sites during the evening. Correlations between landfill and roost counts of ravens were stronger (0.4>r<0.7) when the distance between these sites was <15 km, and smaller (r<0.3) when this distance >20 km. In the spring, ravens dispersed, on average, 38 km from landfills where they were caught. Large congregations of ravens at a few sites in winter may present opportunities to initiate raven population reduction methods to alleviate later problems. I analyzed raven survival and behaviour when USDA/APHIS Wildlife Services (WS) removed ravens using DRC-1339 during winter months. The number of ravens killed annually was 7-34% of the local population. Ravens did not avoid landfills, yet they switched roosts more frequently after an application of the toxicant. Raven removal improves sage-grouse nest success; however, data were not available to examine how raven removal improves sage-grouse abundance. I analyzed changes in raven density with regard to WS removal, and then related these changes with changes in sage-grouse lek counts the following year. Raven densities decreased by 50% from 2008-2014 where WS conducted removal programs. Sage-grouse lek counts improved in area where WS lowered raven abundance, in comparison to areas farther away, during the latter half of the study (2013-2015), when WS removal efforts intensified. Thereafter, a 10% decline in raven abundance was associated with a 2% increase in sage-grouse lek counts. Overall, ravens in souther Wyoming used anthropogenic resources during the winter, and removal of ravens at these locations, combined with removal in the spring, minimally impacted raven populations annually and was associated with increases in sage-grouse abundance.

The decline in greater sage-grouse (Centrocercus urophasianus; sage-grouse) populations across western North America has been primarily attributed to loss and fragmentation of their sagebrush (Artemisia spp.) habitats. This habitat loss is largely the result of increased human activities, with grazing by domestic livestock as the most predominant land use across the sagebrush ecosystem in North America. The goal of my research was to increase our understanding of the effects of livestock on sage-grouse populations. I reviewed the peer-reviewed literature for all published studies that reported potential effects of grazing on grouse species worldwide. I found that there was an overall negative effect of domestic livestock grazing on grouse populations in general. I compared sage-grouse nest success on two study sites managed under differing prescribed livestock grazing practices to determine their relative effects on sage-grouse nest survival. I found that nest survival was slightly higher in areas managed under high-intensity low-frequency rest-rotation practices. The difference was not statistically significant (P < 0.05). However, these areas received lower precipitation and were grazed at a higher stocking rate (AUM · ha-1) without negatively affecting nest survival compared to areas of that were mostly grazed as single pastures from May-September. Because livestock grazing in the sagebrush ecosystem has been historically facilitated with sagebrush reduction treatments to increase forage for livestock, I compared the relative effects of these treatments with the more direct effect from livestock grazing. Sagebrush treatments were found to have a greater effect on female sage-grouse survival than livestock grazing. This understanding can be useful for land managers looking to attenuate the effects of management decisions related to livestock grazing systems in the sagebrush ecosystem.

Environmental impacts of feral horses (Equus caballus) are a subject of conservation concern and controversial national policy. In North America, feral horses are considered an invasive species where they impact rangelands of the arid and semi-arid western United States. The greater sage-grouse (Centrocercus urophasianus) is a native sagebrush obligate bird species that relies on sagebrush habitats to sustain viable population levels. Recent literature suggests that feral horse presence can have a notable effect on the fitness of native and sagebrush obligate species throughout the arid and semi-arid western United States. The purpose of this thesis was to assess the potential impact of feral horses on population patterns and on late-brood rearing habitat of greater sage-grouse throughout the Great Basin. This was accomplished by pairing known sage-grouse use sites (leks and late brood-rearing habitat) to random sites for comparison. Within each pair, one site was located within Herd Management Area (HMA) boundaries (with assumed horse presence) while the other was located outside (with assumed horse absence). We then assessed lek attendance throughout the state of Nevada and compared attendance rates to known horse population estimates. Furthermore, paired late brood-rearing habitat sites were compared to one another to assess the effect of horse and cattle presence on habitat quality and characteristics. We determined that mean sage-grouse population size at leks is higher (9.14 ± 1.04 males) within HMA boundaries compared to areas outside of HMA boundaries (6.55 ± 0.74 males). Considering late brood-rearing habitat, we determined that statistical differences have occurred between horse and non-horse use sites in the following comparisons: annual grass frequency, percent annual grass cover, dung frequency, total plant height, vegetative height, and horse and cattle dung density. We suggest that feral horse presence can impact sage-grouse habitat, however, a more clear understanding of horse effects on rangeland wildlife habitat is needed to assess actual impacts on wildlife populations in consideration of multiple use management decisions.

This study examined population genetics of greater sage-grouse (Centrocercus urophasianus) in Strawberry Valley, Utah located in the north-central part of the state. The Strawberry Valley population of sage-grouse experienced a severe population decline with estimates of abundance in 1998 less than 5% (~150 individuals) of similar estimates from the 1930s (>3,000 individuals). Given the population decline and reduced genetic diversity, recovery team partners translocated sage-grouse from four different populations into Strawberry Valley over 6 years (2003-2008). Translocations have been used as a strategy to increase both population size and genetic diversity in wildlife populations. We assessed whether genetic diversity increased following the translocation of sage-grouse into Strawberry Valley by looking at both nuclear and mitochondrial DNA indices. We observed an overall increase of 16 microsatellite alleles across the 15 loci studied (x̅ =1.04 alleles per locus increase, SE ± 0.25). Haplotype diversity increased from 4 to 5. Levels of genetic diversity increased for both nuclear and mitochondrial DNA (16% and 25% increases for allelic richness and haplotype diversity, respectively). These results show that translocations of greater sage grouse into a wild population can be an effective tool to increase not only population size but also genetic diversity.Second, we studied fitness-related traits and related them to genetic diversity indices in a population of greater sage-grouse in Strawberry Valley, Utah from 2005 to 2013. We captured 93 sage-grouse in Strawberry Valley and fitted them with a radio collar and drew and preserved blood. We monitored sage-grouse weekly, throughout each year. From blood, we extracted and amplified DNA with 15 microsatellite loci. We determined genetic diversity as multilocus heterozygosity and mean d2. To determine if there was a relationship between genetic diversity and survival, we used known-fate models in Program MARK. We also determined if there was a relationship between genetic diversity measures and nest initiation, nest success, clutch size, and number of eggs hatched using generalized linear models where reproductive measures were modeled as a function of genetic diversity. We found no significant relationship between mean d2 and microsatellite heterozygosity with measures of survival or reproductive fitness. Overall, these results suggest that the often-reported strong heterozygosity-fitness correlations detected in small, inbred populations do not reflect a general phenomenon of increasing individual survival and reproductive fitness with increasing heterozygosity.

Declining populations of greater sage-grouse (Centrocercus urophasianus; hereafter sage-grouse) have increased stakeholder concerns regarding the management and stability of the species range-wide. Numerous conservation strategies have been identified to restoring sage-grouse population declines to include species translocations. Translocations have been used for many different wildlife species to help sustain genetic heterogeneity, reestablish, and augment declining populations. In a recent translocation study, researchers identified the protocols used to successfully translocate sage-grouse to restore declining populations in Strawberry Valley, Utah. This translocation occurred in a high elevation basin buffered by geomorphic barriers. I evaluated these protocols for use in translocating sage-grouse to augment a declining population that inhabited Anthro Mountain in northwest Utah. Anthro Mountain is a high elevation mountain dominated by sagebrush (Artemisia spp.) void of geomorphic barriers. I compared annual production, survival (i.e., vital rates), habitat use, and movements of translocated birds and their progeny to the resident population. Lastly, I described the integration of translocated birds with resident birds and the overall efficacy of the translocation effort. I radio-collared and monitored 60 translocated female sage-grouse from Parker Mountain, Utah over a 2-year period (2009 and 2010) and compared their vital rates to 19 radio-marked resident sage-grouse. Adult survival was similar for resident and translocated birds, but higher for both groups in 2010 than in 2009. However, overall survival of both resident and translocated birds was lower than range-wide survival estimates. Nest success was slightly higher for resident birds than translocated birds but positively correlated to grass height for both groups. Chick survival was also slightly higher for resident birds than for translocated birds, and higher overall in 2010 than in 2009. Chick survival was positively correlated to grass cover for both groups. Translocated birds used similar habitats and exhibited migration behaviors similar to resident birds. From a methodology perspective, the translocations protocols were successful because the translocated birds quickly acclimated to the release area, and their survival and reproductive success were similar to the resident birds. The effect of the translocation on augmenting the local population was inconclusive.

This study examined winter habitat use and nesting ecology of greater sage grouse (Centrocercus urophasianus) in Strawberry Valley (SV), Utah located in the north-central part of the state. We monitored sage grouse with the aid of radio telemetry throughout the year, but specifically used information from the winter and nesting periods for this study. Our study provided evidence that sage grouse show fidelity to nesting areas in subsequent years regardless of nest success. We found only 57% of our nests located within the 3 km distance from an active lek typically used to delineate critical nesting habitat. We suggest a more conservative distance of 10 km for our study area. Whenever possible, we urge consideration of nest-area fidelity in conservation planning across the range of greater sage grouse. We also evaluated winter-habitat selection at multiple spatial scales. Sage grouse in our study area selected gradual slopes with high amounts of sagebrush exposed above the snow. We produced a map that identified suitable winter habitat for sage grouse in our study area. This map highlighted core areas that should be conserved and will provide a basis for management decisions affecting Strawberry Valley, Utah.

Small isolated populations are of particular conservation interest due to their increased extinction risk. This dissertation investigates two small wild bird populations using genetic approaches to inform their conservation. Specifically, one case study investigated a Greater Sage-grouse (Centrocercus urophasianus) population located in northwest Wyoming near Jackson Hole and Grand Teton National Park. Microsatellite data showed that the Jackson sage-grouse population possessed significantly reduced levels of neutral genetic diversity and was isolated from other Wyoming populations. Analysis with single nucleotide polymorphisms (SNPs) and microsatellite data provided further evidence that the population's timing of isolation was relatively recent and most likely due to recent anthropogenic habitat changes. Conservation recommendations include maintaining or increasing the population's current size and reestablishing gene flow with the nearest large population. The second case study investigated the genetic distinctiveness of the Floreana island population of the Galápagos Short-eared Owl (Asio flammeus galapagoensis). Mitochondrial DNA sequence data did not detect differences across nine island populations, yet microsatellite and morphometric data indicated that limited gene flow existed with the population and surrounding island populations, which appeared asymmetric in direction from Floreana to Santa Cruz with no indication of gene flow into Floreana. These results have important conservation implications and recommend that the Floreana Short-eared Owl population be held in captivity during the rodenticide application planned for an ecosystem restoration project in 2018. The population is less likely to receive immigrants from surrounding island populations if negatively effected by feeding on poisoned rodents.

While range-wide population declines have prompted extensive research on greater sage-grouse (Centrocercus urophasianus), basic information about southern periphery populations, such as the Bald Hills population in southern Utah, has not been documented. The objective of this research was to determine habitat preferences and space use patterns of the Bald Hills sage-grouse population which occurs in an area of high potential for renewable energy development. I tracked 66 birds via VHF telemetry in 2011 and 2012 and surveyed vegetation plots throughout the study area. I found that the population was primarily one-stage migratory with seasonal distributions that did not correspond well with previously developed suitable habitat maps (based on local biologist knowledge and lek data) for all seasons; I also found that mean home range sizes ranged from 82 km² to 157 km² .

Nesting hens did not select for any measured vegetation characteristics within the study area, while brood-rearing hens selected for high forb cover. Birds at summer sites (non-reproductive bird locations during the summer season) selected for greater grass and forb cover and lower shrub cover compared with random sites. Overall, Bald Hills sage-grouse used areas with greater shrub canopy cover and lower grass and forb cover than recommended in habitat guidelines.

Ten predictor variables were used to model suitable seasonal habitat using Maximum Entropy (maxent). All models were created for the Bald Hills population and projected to the Bureau of Land Management Cedar City Field Office management area and produced excellent model fit (AUC > 0.900). The Bald Hills population had similar nesting and winter habitat preferences as other populations but different brood-rearing and summer habitat preferences. I found local management techniques to be an important driver of seasonal habitat selection; birds selected for areas that had undergone habitat treatments (such as broadcast burn and crushing) within the previous 10 years. My results indicated the Bald Hills periphery population occupies marginal habitat and has adapted unique seasonal habitat preferences. Managers of isolated, fringe, and low-density populations should develop locally specific management guidelines to address the unique adaptations and ensure the persistence of these populations.