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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.
1

Brood Habitat and Invertebrate Biomass of the Greater Prairie Chicken (Tympanuchus cupido pinnatus) in Northwestern Minnesota

Syrowitz, Jennifer 04 April 2013 (has links)
This study assessed the influence of terrestrial invertebrate abundance and vegetation characteristics on northwest Minnesota greater prairie chicken brood success. Radio telemetry was used to determine movements of greater prairie chicken hens and their broods. Invertebrate abundance indices were collected using a sweep net and vegetation data were recorded with overhead and dot-board photographs. Invertebrates were dried, sorted by size and order, and weighed and counted. Vegetation was classified according to life form and height was measured. Greater prairie chicken broods appear to use those habitats most readily available with increased invertebrate resources. Invertebrate biomass was not related to the occurrence of uncultivated forbs which averaged < 17% in Minnesota habitats where greater prairie chicken broods were located. Relatively undisturbed grasslands produce sufficient invertebrate resources to fledge greater prairie chicken chicks. However, location data and invertebrate-habitat indices suggest increased brood success would be likely with improved habitat placement/availability and irregular disturbance regimes that produce beneficial mixed grass/forb vegetation attractive to both greater prairie chicken broods and their invertebrate prey.
2

Brood Habitat and Invertebrate Biomass of the Greater Prairie Chicken (Tympanuchus cupido pinnatus) in Northwestern Minnesota

Syrowitz, Jennifer 04 April 2013 (has links)
This study assessed the influence of terrestrial invertebrate abundance and vegetation characteristics on northwest Minnesota greater prairie chicken brood success. Radio telemetry was used to determine movements of greater prairie chicken hens and their broods. Invertebrate abundance indices were collected using a sweep net and vegetation data were recorded with overhead and dot-board photographs. Invertebrates were dried, sorted by size and order, and weighed and counted. Vegetation was classified according to life form and height was measured. Greater prairie chicken broods appear to use those habitats most readily available with increased invertebrate resources. Invertebrate biomass was not related to the occurrence of uncultivated forbs which averaged < 17% in Minnesota habitats where greater prairie chicken broods were located. Relatively undisturbed grasslands produce sufficient invertebrate resources to fledge greater prairie chicken chicks. However, location data and invertebrate-habitat indices suggest increased brood success would be likely with improved habitat placement/availability and irregular disturbance regimes that produce beneficial mixed grass/forb vegetation attractive to both greater prairie chicken broods and their invertebrate prey.
3

Investigation into the decline of populations of the lesser prairie-chicken (Tympanuchus pallidicinctus Ridgway) in southeastern New Mexico

Hunt, John Loy, January 2004 (has links) (PDF)
Thesis (Ph. D.)--Auburn University, 2004. / Title from PDF title page (viewed on 06/19/2007). Abstract. Vita. Includes bibliographical references.
4

The effects of shinnery oak removal on lesser prairie chicken survival, movement, and reproduction

Leonard, John Peter 15 May 2009 (has links)
The lesser prairie chicken (Tympanuchus pallidicinctus; LPC) has declined in numbers since the late 1800s. Reasons for this decline have been attributed to habitat degradation (decreased forb and grass cover and increased woody cover) and fragmentation caused by overgrazing and conversion of native rangelands to croplands. The herbicide, Tebuthiuron, has been used extensively throughout the LPC’s range to reduce dominance of woody shrubs and allow growth of forbs and grasses. Tebuthiuron treatment of shinnery oak (Quercus havardii) rangelands has been reported as being both beneficial and detrimental to LPC populations. My study evaluated the effects of Tebuthiuran treatment of shinney oak on LPC survival, movement, and reproduction. I trapped (48), radio-tagged (38), and monitored LPC survival, movements, reproduction, and habitat use during spring and summer 2006 and 2007. I also determined potential LPC nest predators using dummy nests (domestic chicken eggs) and motion-sensitive infrared cameras. No differences were found in survival between ages, sexes, or years. Range size did not differ by age, sex, or year. Female LPC moved greater distances from lek of capture than did males. Females nested almost exclusively in non-grazed rangeland and under sand sagebrush (Artemisia filifolia). Nest-sites had higher obstruction of vision (OV), higher (%) woody cover, and lower (%) bare ground than surrounding areas. All LPC were found to use non-grazed rangeland areas more than all other vegetation types, and to use tebuthiuron-treated, grazed areas slightly more than non-treated, grazed areas. Non-grazed rangeland had higher OV than all other vegetation types. Tebuthiuron treatment lowered woody plant dominance and increased forbs and grasses. Fire reduced vegetation height and OV and increased growth of grasses and forbs, but did not kill woody vegetation as did tebuthiuron-treatment. The most common dummy nest predator found was the Chihuahuan raven (Corvus cryptoleucus).
5

Lesser prairie-chicken demographics in Texas: survival, reproduction, and population viability

Lyons, Eddie Keith 15 May 2009 (has links)
Lesser prairie-chickens (Tympanuchus pallidicinctus) have declined throughout their range because of overgrazing and loss or fragmentation of habitat from conversion of native prairie to agricultural cropland. Lesser prairie-chickens were radio-marked (n = 225) as part of 2 separate field studies in the Texas Panhandle (2001–2003, 2003– 2007). These data were used to evaluate whether differences in demographic parameters existed between populations occurring in 2 areas dominated by different vegetation types (sand sagebrush [Artemisia filifolia] versus shinnery oak [Quercus havardii]) in the Texas Panhandle from 2001–2007. A model-selection approach was used to test hypotheses explaining differences in survival and reproductive success of lesser prairiechickens. Additionally, a population viability analysis was constructed using the above demographic parameters to evaluate effects of harvest and no harvest scenarios on viability and population persistence of lesser prairie-chickens in Texas. Overall, survival, reproduction, and population viability were lower in the shinnery oak compared to the sand sagebrush vegetation type. Lesser prairie-chicken survival differed between breeding and non-breeding periods. I estimated annual survival of lesser prairiechickens at 31% in the shinnery oak and 52% in the sand sagebrush vegetation type. Nest success was (41%, 95% CI = 25–56%) in the shinnery oak population compared to the sand sagebrush population (75%, 95% CI = 54–94%). Population viability analysis predicted continued declines in lesser prairie-chicken populations in Texas. Estimates of local occupancy indicated lesser prairie-chicken populations would go extinct in the southwestern shinnery oak vegetation type more quickly compared to the northeastern sand sagebrush vegetation type (approximately 10 years compared to 30 years, respectively) without changes in population vital rates. Harvest at all levels increased risk of extinction. Results suggest that differences in survival and reproduction of lesser prairie-chickens within sand sagebrush and shinnery oak vegetation types throughout the Texas Panhandle should be evaluated, especially during the breeding season. Improvements to vegetation conducive for successful nesting are important to the viability of lesser prairie-chickens. Conservation and recovery strategies for lesser prairie-chicken populations should address variables that increase survival and nest success and consideration of no harvest.
6

The role of fire, microclimate, and vegetation in lesser prairie-chicken habitat selection

Lautenbach, Jonathan David January 1900 (has links)
Master of Science / Division of Biology / David A. Haukos / The lesser prairie-chicken is a prairie grouse native to the southwestern Great Plains that has experienced significant population and habitat declines since European settlement. Ongoing declines prompted the U.S. Fish and Wildlife Service to list lesser prairie-chickens as threatened under the Endangered Species Act in spring of 2014. In fall of 2015, the listing was vacated on procedural grounds and the lesser prairie-chicken was removed from listing in summer 2016. Despite the legislative change, considerable conservation efforts emerged with the initial listing and have continued following the removal of the species from the threatened and endangered species list. Understanding how lesser prairie-chickens use landscapes and how management actions can influence their space use is important for long-term strategies to meet conservation goals. I modeled lesser prairie-chicken habitat selection relative to landscape mosaics of vegetation patches generated through patch-burn grazing, microclimate, and vegetation characteristics across their range. I captured, attached GPS satellite or VHF radio transmitters to, tracked, and measured vegetation characteristics used by and available to female lesser prairie-chickens across the northern portion of their range in Kansas and Colorado. Female lesser prairie-chickens use all patch types created in a patch-burn grazing mosaic, with female selecting greater time-since-fire patches (>2-years post-fire) for nesting, 2-year post-fire patches during the spring lekking season, 1- and 2-year post-fire patches during the summer brooding period, and 1-year post-fire units during the nonbreeding season. Available vegetation structure and composition in selected patches during each life-cycle stage was similar to the needs of female lesser prairie-chickens during that life-cycle stage. To assess their selected microclimate conditions, I deployed Maxim Integrated Semiconductor data loggers (iButtons) at female flush locations and across a landscape inhabited by lesser prairie-chickens. Females selected locations that minimized thermal stress at microsite, patch, and landscape scales during peak midday temperatures during summer. Females selected midday locations based on vegetation characteristics; where selected sites had >60% forb cover and <25% grass cover, or >75% grass cover and <10% forb cover. In addition, females selected sites with greater visual obstruction. I measured vegetation composition and structure at use and available sites at four study areas located along the precipitation gradient characterizing the full extent of the lesser prairie-chicken range. Vegetation structure use by females varied in relation to long-term precipitation patterns. Females used sites with lower visual obstruction than available during the fall and spring. However, they used vegetation composition that was similar to available within each study area. Overall, my findings indicate that lesser prairie-chickens require structural and compositional heterogeneity to support a suite of habitat needs throughout the year. Therefore, management should focus on providing structural and compositional heterogeneity across landscapes. Greater heterogeneity in vegetation conditions can be achieved through management practices that allow domestic grazers to select grazing locations, such as patch-burn grazing or increased pasture area.
7

SEASONAL SURVIVAL, REPRODUCTION, AND USE OF WILDFIRE AREAS BY LESSER PRAIRIE CHICKENS IN THE NORTHEASTERN TEXAS PANHANDLE

Jones, Ryan S. 2009 May 1900 (has links)
Lesser prairie chicken (Tympanuchus pallidicinctus) numbers have declined considerably in Texas since the early 1900s. Conversion of native prairie to cropland has been the major cause of the decline. I trapped and monitored 115 (66 males, 49 females) lesser prairie chickens in the Rolling Plains of the Texas Panhandle from 2001 through 2003. I used an information-theoretic approach to model selection as implemented in program MARK to evaluate factors contributing to variation in survival and differences in nest success. I found breeding season survival of both males and females was lower compared to non-breeding season survival. Annual survival was 0.52 (95% CI: 0.32? 0.71). Model selection indicated higher nest success (70%) in the sand sagebrush (Artemisia filifolia) vegetation type as compared to the shinnery oak (Quercus harvardii) type (40%). I also evaluated post-burn habitat alterations and plant succession (1 year and 2 years after burning) as potential lesser prairie chicken habitat. After spring rainfalls stimulated re-growth of herbaceous plants, male lesser prairie chickens moved to the site, feeding on new-emerging forbs throughout the summer. A female lesser prairie chicken with a brood used the burned site during the first summer after the burn. A year later, males established a lek on the burned site. Two female lesser prairie chickens with broods used the burned site during the second summer. Burned sites had more forbs than nonburned sites and probably had more insects available which are an important food source for chicks during their first 4?5 weeks of age.
8

Mating and interspecific behavior of greater prairie chicken

Anderson, Raymond Kenneth, January 1969 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
9

Cloacal Microbiota of Captive-bred and Wild Attwater’s Prairie-chicken, Tympanuchus Cupido Attwateri

Simon, Stephanie E. 08 1900 (has links)
The Attwater’s prairie-chicken (Tympanuchus cupido attwateri; APC) is a species of grouse native to Texas coastal prairies and is on the critically endangered species list as a result of habitat destruction and overhunting. All of the current populations were captively bred and released into the wild. Survivorship for released APCs is very low, and individuals seldom survive to reproduce in the wild. One factor contributing to this may be an alteration in the gut microbiota as a result of captivity. Factors potentially influencing the gut microbial composition in captivity include antibiotic therapy, stress, and a predominantly commercially formulated diet. Recent studies have begun to shed light on the importance of the host microbial endosymbionts. Antibiotic administration, stress, diet, age, genotype and other factors have been shown to influence microbial populations in the gastrointestinal tracts of many different vertebrates. Sequencing of 16S rRNA gene amplicons on the Ion Torrent™ platform was used in this study to identify groups of bacteria in the cloacas as a surrogate for the gut microbiota in the APC. Antibiotic-treated and untreated birds, wild-hatched and captive-bred birds, and individuals sampled before and after release to the wild were examined. Significant differences were found between wild-hatched and captive raised birds both pre- and post release. In addition, there was extensive variation among the populations at the lower taxonomic ranks between individuals for each group of APCs. Principal coordinate analysis based on the weighted UniFrac distance metric further exhibited some clustering of individuals by treatment. These data suggest that captive breeding may have long-term effects on the cloacal microbiota of APCs with unknown consequences to their long-term health and survivorship.
10

Extensive investigation of reticuloendotheliosis virus in the endangered Attwater's prairie chicken

Bohls, Ryan Lanier 17 September 2007 (has links)
Reticuloendotheliosis virus (REV) is a retrovirus that causes a neoplastic disease in a wide range of avian hosts including chickens, turkeys, and ducks. In 1993, REV was detected in the endangered Attwater's prairie chicken (Tympanachus cupido attwateri), a subspecies of Tympanachus cupido. Subsequent infections of this prairie chicken have been identified at captive breeding facilities throughout Texas. The implications of these infections have severely hindered repopulation efforts by these facilities. This study focused on investigating REV infection of captive Attwater'€™s prairie chicken in order to better understand the disease affecting these endangered birds. The overall objective was to develop a means of eliminating this threat to the repopulation of the Attwater's prairie chicken. Several aspects of virus infection were investigated. Reagents capable of recognizing prairie chicken IgY and viral gag polypeptides were developed for use in assays for detection of antibody responses and titration of viral concentrations. Sequencing data of genomes collected from isolates of Texas prairie chickens and domestic chickens, as well as three REV prototype viruses, were compared to determine relationships among strains and identify the potential origin of the REV infecting Attwater'€™s prairie chicken. Additionally, a flow cytometry technique of segregating the lymphocyte population from peripheral blood mononuclear cells (PBMC) using a pan leukocyte monoclonal antibody was developed to more accurately measure changes within lymphocyte populations. This technique combined with intracellular labeling was used to deduce the target cells of REV infection. A nested polymerase chain reaction (PCR) test was developed for greater sensitivity in detecting infection in birds than the previous method of single amplification PCR. This greater sensitivity results in earlier identification of the virus in infected birds, which allows for earlier removal of infected birds to minimize transmission of the virus throughout the flock. The sensitivity of the nested PCR diagnostic test was determined in a dose response pathogenesis study, which was conducted on hybrid greater/Attwater's prairie chicken to observe the experimental development of disease in these birds. Finally, a vaccine was developed using plasmid DNA with REV encoded genes and tested on naturally infected prairie chickens to determine its efficacy in reducing viral load. Although no reduction in viral load was detected, the vaccine may be effective in providing prophylactic protection in future studies.

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