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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Sage-grouse and the human footprint implications for conservation of small and declining populations /

Tack, Jason Duane. January 2010 (has links)
Thesis (MS)--University of Montana, 2010. / Contents viewed on February 8, 2010. Title from author supplied metadata. Includes bibliographical references.
62

Nest site selection and nest success of greater sage-grouse in Mono County, California

Kolada, Eric J. January 2007 (has links)
Thesis (M.S.)--University of Nevada, Reno, 2007. / "December, 2007." Includes bibliographical references. Online version available on the World Wide Web.
63

Ecology of predation and ruffed grouse populations in central Alberta

Rusch, Donald H. January 1971 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1971. / Vita. Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
64

Habitat Used by Ruffed Grouse in Northern Utah

Landry, Judith L. 01 May 1982 (has links)
Vegetation structure of sites used by ruffed grouse (Bonasa umbellus) hens with brood, solitary grouse, drumming males, and nesting hens in northern Utah was measured in 1979 and 1980 . Univariate statistical techniques were used to determine general habitat characteristics of each group and discriminant function analysis was applied to the data to differentiate among groups. Most nests were located in maple stands (Acer grandidentatum and A. negundo) with dense tree canopies, low shrubs, and sparse ground vegetation. Drumming logs were most commonly found in densely stocked stands of aspen (Populus tremuloides) mixed with maple or chokecherry (Prunus virginiana) having a well-developed shrub layer and good horizontal visibility. The most important component of habitat used by solitary grouse was the dense shrub layer that apparently provided protection from precipitation, extreme temperatures, and predators. Hens with brood were commonly associated with aspen and mixed aspen stands which had open canopies, sparse shrub growth, and tall ground cover. Near the end of July, hens with brood began using habitat similar to that used by solitary grouse. The degree of horizontal visibility best separated habitat used by hens with brood and solitary grouse from the more open habitat associated with drumming logs and nest sites. Open tree canopy cover and tall shrubs best differentiated between habitat used by hens with brood from that used by solitary grouse. In general, many structural characteristics of habitat used by ruffed grouse in northern Utah appear similar to those reported in other areas of the species' range . Management strategies for use here should, however, be developed for small "islands" of habitat and emphasize enhancing structural and species diversity by planning for mixed aspen stands with a well-developed shrub layer.
65

Seasonal Distribution of Sage-Grouse in Hamlin Valley, Utah and the Effect of Fences on Grouse and Avian Predators

McPherron, Heather Hedden 01 December 2017 (has links)
Greater sage-grouse (Centrocercus urophasianus; hereafter sage-grouse) numbers have declined throughout the western US and are considered a species of concern in most of the eleven states that are within their range. Sage-grouse habitats have been reduced by approximately 44% since European settlement of the Western United States began (Miller et al. 2011). Loss of habitat has contributed to an average decline of sage-grouse populations by 33% across the range (Connelly and Braun 1997). To expand our knowledge of this species, I monitored 16 radio-collared sage-grouse captured from four leks in Hamlin Valley, Utah, USA in 2011 and 2012 to determine habitat use. The Hamlin Valley population was primarily one-stage migratory but non-migratory behaviors were also observed. Birds from at least one of the leks used seasonal habitats in neighboring Nevada. Sage-grouse evolved in habitats where infrastructure (e.g. vertical structures) was not common. Introduction of infrastructure, such as fences in their habitat, can cause direct mortality via collision but may also indirectly influence productivity by increasing artificial perches for avian predators (e.g. golden eagles (Aquila chrysaetos) , red-tailed hawks (Buteo jamaicensis), and common ravens (Corvus corax). This research focused on collision rates and increased potential for avian predation on two small populations on the southern portion of the range of current occupied sage-grouse habitat in southwestern vi Utah. During 2011-2012, over 450 km of fences were surveyed for signs of collision and use by avian predators during all seasons (breeding, fall migration, and winter). No sage-grouse collisions were observed suggesting that management for sage-grouse in small populations may be better focused on improving habitat and reducing other causes of mortality which may be more prevalent. Fence post width (i.e. the perching surface) was the best predictor of use as perch by avian predators. Additionally, areas farther from other natural perches, with a low density of surrounding vegetation, and fences constructed along defined habitat edges were used by avian predators more frequently. Results of this study suggest that managers should construct fences with small widths to deter avian predators and care should be taken to maintain contiguous vegetation on either side of the posts while maintaining low shrub density.
66

A study on the blood protozoa of blue grouse on Vancouver Island

Woo, Patrick Tung Kee January 1964 (has links)
The present study demonstrates that blue grouse on Vancouver Island are infected with two species of Haemoproteus, probably two species of Leucocytozoon and a species of Trypanosoma. Haemoproteus dendragapi n.sp. is described from the Nanaimo Lakes Area. The growth rate of H. canachites gametocytes is much more rapid than that described by Fallis in Ontario. The very young tissue stages of H. canachites are described from lung preparations of grouse chicks. The life cycle of Leucocytozoon bonasae has been completed by using a new vector, Cnephia minus. As reported by Fallis in Ontario, Simulium aureum has been found to be a vector of L. bonasae on Vancouver Island. This study has verified Woodcock's often ignored hypothesis that the morphology of the gametocyte-host cell complex changes with age of infection. A probable new species of Leucocytozoon is described from the Campbell River Area. In-vitro culture of the trypanosome from grouse blood has been carried out. A yearling blue grouse has been successfully infected by inoculation of metacyclic trypansomes from the culture. / Science, Faculty of / Zoology, Department of / Graduate
67

Greater Sage-Grouse Response to Sagebrush Reduction Treatments in Rich County, Utah

Stringham, Roger Blair 01 May 2010 (has links)
Management of greater sage-grouse (Centrocercus urophasianus) in the west has changed over the last several decades in response to environmental and anthropogenic causes. Many land and wildlife management agencies have begun manipulating sagebrush with herbicides, machinery, and fire. The intent of these manipulations (treatments) is to reduce sagebrush canopy cover and increase the density of grass and forb species, thus providing higher quality sage-grouse brood-rearing habitat. However, monitoring of sage-grouse response to such manipulations has often been lacking or non-existent. The objective of our study was to determine the response of sage-grouse to sagebrush reduction treatments that have occurred recently in Rich County, Utah. Our study areas were treated with a pasture aerator with the intent of creating sage-grouse brood-rearing habitat. We used pellet transects, occupancy sampling, and GPS radio telemetry to quantify sage-grouse habitat use in treated and untreated areas. Pellet transect, occupancy, and GPS radio telemetry methods all showed a strong pattern of sage-grouse use of treated sites during the breeding and early brood-rearing periods. Sage-grouse use of treated sites was greatest in lower elevation habitat (1950 to 2110 m), and use was highest during the breeding and early brood-rearing periods. We found very little use of higher elevation (2120 to 2250 m) treated or untreated sites. Our results suggest that sagebrush reduction treatments can have positive impacts on sage-grouse use at lower elevations and can be successful in creating brood-rearing habitat. Elevation differences and period of sage-grouse use were significant factors in our study in determining how beneficial sagebrush reduction treatments were for sage-grouse.
68

Inferring demographic history and speciation of grouse using whole genome sequences

Kozma, Radoslav January 2016 (has links)
From an ecological perspective, knowledge of demographic history is highly valuable because population size fluctuations can be matched to known climatic events, thereby revealing great insight into a species’ reaction to past climate change. This in turn enables us to predict how they might respond to future climate scenarios. Prominently, with the advent of high-throughput sequencing it is now becoming possible to assemble genomes of non-model organisms thereby providing unprecedented resolution to the study of demographic history and speciation. This thesis utilises four species of grouse (Aves, subfamily Tetraoninae) in order to explore the demographic history and speciation within this lineage; the willow grouse, red grouse, rock ptarmigan and the black grouse. I, and my co-authors, begin by reviewing the plethora of methods used to estimate contemporary effective population size (Ne) and demographic history that are available to animal conservation practitioners. We find that their underlying assumptions and necessary input data can bias in their application, and thus we provide a summary of their applicability. I then use the whole genomes of the black grouse, willow grouse and rock ptarmigan to infer their population dynamics within the last million years. I find three dominant periods that shape their demographic history: early Pleistocene cooling (3-0.9 Mya), the mid-Brunhes event (430 kya) and the last glacial period (110-10 kya). I also find strong signals of local population history – recolonization and subdivision events – affecting their demography. In the subsequent study, I explore the grouse dynamics within the last glacial period in more detail by including more distant samples and using ecological modelling to track habitat distribution changes. I further uncover strong signals of local population history, with multiple fringe populations undergoing severe bottlenecks. I also determine that future climate change is expected to drastically constrict the distribution of the studied grouse. Lastly, I use whole genome sequencing to uncover 6 highly differentiated regions, containing 7 genes, hinting at their role in adaptation and speciation in three grouse taxa. I also locate a region of low differentiation, containing the Agouti pigmentation gene, indicating its role in the grouse plumage coloration.
69

A Study of the Sage Grouse (Centrocercus urophasianus), With Special Reference to Life History, Habitat Requirements, and Numbers and Distribution

Griner, Lynn A. 01 May 1939 (has links)
The sage grouse or sage hen Centrocercus urophasianus (Bonaparte) was formerly the most important upland native game bird of the Western States, but has steadily been declining in numbers over most of its range in recent years. This reduction in numbers has aroused the interest of the conservationists of the nation, who, for the past decade or more, have been proposing that something be done for this game species. In recent years along with this interest of the conservationists, there has been an increasing local interest among the sportsmen of the West, with the result that several groups have become interested in making a study of the sage grouse and determining reasons for the marked decline in its numbers. Partly because of this aroused interest, the study of the sage grouse was selected as a research project.
70

Ecology of Greater Sage-Grouse Inhabiting the Southern Portion of the Rich-Morgan-Summit Sage-Grouse Management Area

Flack, M. Brandon 01 December 2017 (has links)
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.

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