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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

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.
2

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).
3

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.
4

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.
5

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.
6

Survival, seasonal movements, and cover use by lesser prairie chickens in the Texas Panhandle

Toole, Benjamin Edwin 01 November 2005 (has links)
Lesser prairie chicken (Tympanuchus pallidicinctus; LPC) numbers have declined considerably in Texas since the early 1900s. As with other prairie chicken species, reasons for declining ranges and numbers have been attributed primarily to degradation and fragmentation of habitats. Until my study, no telemetry-based research on LPC has been conducted in the Rolling Plains of the Texas Panhandle. I radio-tagged and monitored LPCs in 2001 (spring??winter) and 2002 (spring) at a stable population in a native rangeland landscape (Study Area I) and in a declining population in a fragmented rangeland and agricultural landscape (Study Area II). No significant (P < 0.05) differences in survival were detected for combined study areas between years, or between study areas within years. Ranges and movements, as independent criteria by season, sex, and age classes combined were similar (P > 0.05) for both study areas. Lesser prairie chickens predominately occupied native rangeland cover types (>85%) compared to non-native rangelands at both study areas. Total invertebrate dry mass for all orders differed between native rangeland and Conservation Reserve Program (CRP) sites at Study Area II. Over 32 times more dry mass of invertebrates was collected at the native rangeland site than were collected at the CRP site. Herbaceous cover differed significantly for grasses (P < 0.01), forbs (P < 0.01), and bare ground (P < 0.01), but not for litter (P = 0.43) or woody cover (P = 0.63) between study areas. The similar range sizes, movement distances, and cover use observed for both study areas may provide insight into minimum area requirements for LPCs within the Rolling Plains in the Texas Panhandle.
7

Vegetation characteristics and lesser prairie chicken responses to land cover types and grazing management in western Kansas

Kraft, John Daniel January 1900 (has links)
Master of Science / Department of Biology / David A. Haukos / In the southern Great Plains, the lesser prairie-chicken (Tympanuchus pallidicinctus; hereafter LEPC), an obligate grassland species, has experienced significant population declines and range contractions with subsequent conservation concern. Management actions often use land cover types to make inference about habitat quality. Relatively little information is available related to grazed rangelands to guide conservation. The influences of land cover types and livestock grazing on LEPC habitat selection have not been researched extensively in western Kansas. I evaluated the influence of land cover types and grazing management on vegetation characteristics, habitat selection, and nest/adult survival of LEPC in western Kansas. Females were captured and radio-marked to monitor habitat use, nest success, and adult survival. Grazing and vegetation data were collected via producer correspondence and vegetation surveys, respectively. Vegetation composition and structure differed across land cover types, which can be used to make inferences about LEPC habitat quality. Habitat selection analyses corroborated the importance of breeding habitat in close proximity to leks (<3 km) and identified land cover types selected for nesting (Conservation Reserve Program, Limy Upland, Saline Subirrigated) and brooding (Conservation Reserve Program, Red Clay Prairie, Sands, Sandy Lowland). Conservation Reserve Program patches positioned near rangelands contributed to LEPC reproductive success in northwest Kansas. In grazed lands, LEPC selected habitat close to leks (<3 km) and large pastures (>400 ha), exhibiting low-moderate stocking densities (<0.4 AU/ha), and low-moderate levels of deferment during the grazing season (60-100 days). Nest site selection was negatively influenced by increasing distance from a lek and grazing pressure. Daily nest survival rates were negatively influenced by increasing grazing pressure and high levels of stocking density. Annual adult female survival was negatively influenced as forage utilization (% forage removed) increased. Heterogeneity (coefficient of variation and standard deviation) of visual obstruction was decreased at stocking densities > 0.26 AU/ha. Future conservation actions should consider the potential of land cover types to create adequate vegetation structure, and manage rangelands with low-moderate stocking densities and deferment and greater pasture areas. The relationship between habitat selection and proximity of lek sites (< 5 km) should be used to identify quality LEPC habitat.
8

Lesser prairie-chicken movement, space use, survival, and response to anthropogenic structures in Kansas and Colorado

Plumb, Reid Thomas January 1900 (has links)
Master of Science / Biology / David A. Haukos / The lesser prairie-chicken (Tympanuchus pallidicinctus) is an endemic North American prairie grouse once widely distributed in the southwestern Great Plains. Recent population declines and continued threats to lesser prairie-chicken populations prompted the U.S. Fish and Wildlife Service to list the species as “threatened” under the protection of the Endangered Species Act of 1973 in May 2014. The northern extent of the species range in Kansas and Colorado supports 2/3 of the remaining range-wide population of lesser prairie-chickens, but has thus far been relatively understudied. Concern for species viability has created a need to fill current knowledge gaps in lesser prairie-chicken ecology, provide more recent demographic information, and develop appropriate conservation actions. I evaluated female survival, movement, space use, and effects of anthropogenic features during the breeding seasons of 2013 and 2014. I captured and radio-tagged 201 females with satellite GPS (N = 114) and VHF (N = 82) transmitters within the three ecoregions of Kansas and Colorado. Mean daily movement varied by region, year, and breeding season period but the amount of space used was consistent between ecoregions and years. On average, females moved 1352 m ± 12 [SE] per day. Females moved the greatest distances during the lekking period of the breeding season with females moving 2074 m ± 36 per day. Females were most sedentary during the brooding period moving only 780 m ± 14 per day. Mean breeding season home range size was estimated to be 340 ha ± 27. The lekking period had the greatest amount of movement as a result of females visiting leks to find mates, copulate, and search for nest locations. Female’s movements were reduced during the brooding period because of physical limitations of the brood mobility. Variation in movement between ecoregions was most likely a product of fragmentation as females moved 10-30% more in northwest Kansas compared to the study sites, which was characterized by northwest Kansas having the greatest degree of fragmentation. Survival varied by ecoregion with females in northwest Kansas having the lowest probability of surviving the 6-month breeding season compared to other ecoregions. Estimated 6-month breeding season survival during 2013 and 2014 was 0.455 (95% CI = 0.38 – 0.53). Survival was lowest during the nesting period, which claimed 59.5% of all observed mortalities. Survival increased from 2013 to 2014 in northwest Kansas as grassland habitats recovered from extreme drought conditions in 2013. Drought was less severe in south-central Kansas and survival rates remained fairly consistent across years. Avian and mammalian predators caused 45.7% and 34.3% of breeding season mortalities, respectively. Other mortalities were either cause by snakes or were unknown (5.7%, 14.3%). Overhead cover may have been limited from drought conditions causing nesting females to be more visible to avian predators during incubation. When pooled across years and ecoregions, rump-mounted GPS transmitters did not adversely affect female survival when compared to commonly used necklace style VHF transmitter (VHF: 0.48 95% CI = 0.39 – 0.58; GPS: 0.50 95% CI = 0.38 – 0.64). Distance to distribution power lines and lek were significant predictors of female space use within their home range with females behaviorally avoiding distribution power lines and using space closer to leks. Space use decreased with increasing oil well density. Females avoided areas that had well densities of 23 wells/250 ha. Observed female locations were further from anthropogenic features but closer to leks on average than at random. Avoidance behavior of anthropogenic features may result in functional habitat loss and reduce the amount of suitable habitat available; compounding previously fragmented landscapes. Anthropogenic features may limit movement by acting as barriers on the landscape and potentially disrupt population connectivity. Furthermore, habitats selected for nesting and brooding may result in potential ecological traps because of reduce breeding success when impacted by increased occurrence and densities of anthropogenic features. Reduced breeding success can have significant negative impacts on population persistence. Average home range size across all ecoregions indicated that female lesser prairie-chickens need at least 340 ha of habitat to fulfill her life-history requirements during the breeding season. Brooding habitats need to be in close proximity (≤ 750 m) to nesting cover to reduce distance traversed by newly hatched broods. Reducing grazing pressure will ensure that sufficient vertical habitat structure is available during the nesting period and increase female survival; especially in times of drought. Mangers should restrict construction of anthropogenic features near or within suitable lesser prairie-chicken habitat with emphasis on distribution power lines. Well densities should not exceed 1 well/60 acres (11 wells/section) for a >10% probability of use. However, because the affect that density of wells has on demographic rates of lesser prairie-chickens has yet to be determined, a conservative approach where well densities in or adjacent to grassland patches should be minimized as much as possible is best.
9

Landscape ecology, survival and space use of lesser prairie-chickens

Robinson, Samantha January 1900 (has links)
Master of Science / Biology / David A. Haukos / The lesser prairie-chicken (Tympanuchus pallidicinctus) has experienced range-wide population declines and range contraction since European settlement. Due to ongoing declines, lesser prairie-chickens were listed as threatened under the Endangered Species Act in 2014; however, uncertainty regarding the legal status of the species has developed following a judicial decision to vacate the listing in September 2015. Regardless, new research is required for conservation planning, especially for understudied portions and temporal periods of the occupied range. I evaluated nonbreeding lesser prairie-chicken survival using known-fate models, and tested for the influence of environmental, landscape and predator effects on weekly survival. I estimated nonbreeding home-range size using fixed kernel density estimators and Brownian Bridge movement models for VHF and Satellite tagged lesser prairie-chickens, and measured habitat use during the 6-month nonbreeding period (16 September – 14 March). I also determined the influence of lek location on space use intensity within home ranges using resource utilization functions. Female survival was high (0.75, SE = 0.05) and consistent across nonbreeding seasons, but not explainable by selected variables. Mean home range size for birds with GPS transmitters (955 ha, SE = 128.5) was 215% larger than for individuals with VHF transmitters (303 ha, SE = 24.1) and 136% greater during the 2014-2015 nonbreeding season than the 2013-2014 season. Males and females were tied to leks throughout the nonbreeding season, and this relationship was not variable across the months of the nonbreeding season. Proportions of habitat used differed among study sites, but temporal trends were not evident. Lesser prairie-chickens exhibited consistency among ecoregions for home-range, space use, and survival; however, with differing habitat use among regions, management should be on the regional scale. Agriculture and energy development have caused fragmentation of the landscape where lesser prairie-chickens evolved. I used known fate survival models to test if landscape composition or configuration within sites caused survival to differ by site, as well as within home ranges to determine if functional relationships exist between weekly survival and landscape configuration or composition. I used Andersen-Gill models to test whether distance to anthropogenic features affected hazard rates. Differences in survival rates between sites, with survival rates 50% greater in Clark County, Kansas compared to Northwestern, Kansas, corresponded to differences in the amount of grassland habitat on the landscape, but study-site configuration was not measurably different. Increasing the number of patch types within home ranges increased survival, indicating positive effects of heterogeneity. In addition, as distance to fences decreased, lesser prairie-chickens experienced greater risk. Overall, further breakup of grassland landscapes that lesser prairie-chickens occupy should be avoided, to avoid habitat loss and fragmentation thresholds that could further affect survival rates. Additionally, fences should be removed or avoided around active leks.
10

A historical record of land cover change of the lesser prairie-chicken range in Kansas

Spencer, David A. January 1900 (has links)
Master of Science / Department of Geography / Melinda Daniels / The Lesser Prairie-Chicken (Tympanuchus pallidicinctus) is a prairie grouse of conservation concern in the Southern Great Plains. In response to declining population numbers and ongoing threats to its habitat, the Lesser Prairie-Chicken was listed as threatened under the Endangered Species Act in May 2014. In western Kansas, the Lesser Prairie-Chicken occupies the Sand Sagebrush Prairie, Mixed-grass Prairie, and Short-grass/CRP Mosaic Ecoregions. Since the beginning of the 20th century, the overall range and population has declined by 92% and 97% respectively. Much of this decline is attributed to the loss and fragmentation of native grasslands throughout the Lesser Prairie-Chicken range. Whereas much of the loss and degradation of native grassland have been attributed to anthropogenic activities such as conversion of grassland to cropland and energy exploration, federal legislation since the 1980s to convert cropland on highly erodible soils to perennial grasses through the U.S. Department of Agriculture (USDA) Conservation Reserve Program (CRP) may curtail or reverse these trends. My objective was to document changes in the areal extent and connectivity of grasslands in the identified Lesser Prairie-Chicken range in Kansas from the 1950s to 2013 using remotely sensed data. I hypothesized that the total amount of grassland decreased between the 1950’s and 2013 because of an increase in agricultural practices, but predicted an increase of grassland between 1985 and 2013 in response to the CRP. To document changes in grassland, land cover maps were generated through spectral classification of LANDSAT images and visual analysis of aerial photographs from the Army Map Service and USDA Farm Service Agency. Landscape composition and configuration were assessed using FRAGSTATS to compute a variety of landscape metrics measuring changes in the amount of grassland present as well as changes in the size and configuration of grassland patches. Since 1985, the amount of grassland in the Lesser Prairie-Chicken range in Kansas has increased by 210,9963.3 ha, a rise of 11.9%, while the mean patch size and area-weighted mean patch size of grassland increased 18.2% and 23.0% respectively, indicating grassland has become more connected during this time in response to the CRP. Prior to the implementation of CRP, the amount of grassland had been decreasing since 1950, as 66,722.0 ha of grassland was converted to croplands. The loss of grassland had a considerable effect on the patch size of grasslands, as mean patch size and area-weighted mean patch size decreased by 8.8% and 11.1% respectively. The primary driver of grassland loss between 1950 and 1985 was the emergence of center pivot irrigation, which had its greatest impact in western and southwestern parts of the range in Kansas. In particular, while the amount of grassland in Range 5, a region of the Lesser Prairie-Chicken range found in southwest Kansas, has increased overall since the 1950s by 4.7%, the area-weighted mean patch size has decreased by 53.0% in response to center pivot irrigation fragmenting the landscape. While the CRP has been successful in increasing and connecting grassland throughout the Lesser Prairie-Chicken range to offset the loss of grassland since the 1950s, continuation of the CRP faces an uncertain future in the face of rising commodity prices, energy development, and reduction in program scope leaving open the possibility that these areas that have created habitat for Lesser Prairie-Chickens could be lost. As time progresses, a reduction in the scope of the CRP would reduce the amount of habitat available to Lesser Prairie-Chickens, threatening the persistence of their population.

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