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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.
11

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.
12

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.
13

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.
14

The Effects of Inbreeding on Fitness Traits in the Critically Endangered Attwater’s Prairie-chicken

Hammerly, Susan C. 08 1900 (has links)
The goals of captive breeding programs for endangered species include preserving genetic diversity and avoiding inbreeding. Typically this is accomplished by minimizing population mean kinship; however, this approach becomes less effective when errors in the pedigree exist and may result in inbreeding depression, or reduced survival. Here, both pedigree- and DNA-based methods were used to assess inbreeding depression in the critically endangered Attwater’s prairie-chicken (Tympanuchus cupido attwateri). Less variation in the pedigree-based inbreeding coefficients and parental relatedness values were observed compared to DNA-based measures suggesting that errors exist in the pedigree. Further, chicks identified with high parental DNA-based relatedness exhibited decreased survival at both 14- and 50-days post-hatch. A similar pattern was observed in later life stages (> 50 days post-hatch) with birds released to the wild; however, the pattern varied depending on the time post-release. While DNA-based inbreeding coefficient was positively correlated with mortality to one month post-release, an opposite pattern was observed at nine months suggesting purging of deleterious alleles. I also investigated whether immunocompetence, or the ability to produce a normal immune response, was correlated with survival; however, no significant correlation was observed suggesting that inbreeding was a more important factor influencing survival. Pairing individuals for breeding by minimizing DNA-based parental relatedness values resulted in a significant increase in chick survival. This study highlights the importance of using DNA-based methods to avoid inbreeding depression when errors exist in the pedigree.
15

An analysis of greater prairie-chicken demography in Kansas: the effects of human land use on the population ecology of an obligate grassland species

McNew, Lance B. Jr. January 1900 (has links)
Doctor of Philosophy / Department of Biology / Brett K. Sandercock / Greater prairie-chicken (Tympanuchus cupido) populations have been reduced by >70% since the turn of the 20th century due to large-scale conversion of native prairie habitats to cultivated agriculture and other human development. Although Kansas is considered a stronghold for greater prairie-chickens, statewide populations have declined >30% in the last 30 years. Goals of this dissertation were to determine the demographic mechanisms for apparent population declines and evaluate how regional variations in landscape composition and grassland management affect the demography, habitat use, life-history, and population viability of three populations of greater prairie-chickens. First, I found that, despite high reproductive potential, poor reproductive success prevented populations from being self-sustaining. All three populations were projected to decline but finite rates of population declines were different among populations (λ = 0.49, 0.54, and 0.74). I found that grassland fragmentation and rangeland management practices influence nearly every aspect of greater prairie-chicken population ecology and dynamics. A population in a contiguous prairie landscape managed with annual spring burning and intensive early stocking of cattle (South) was characterized by delayed breeding, low nest and brood survival (0.08–0.18 and 0.27, respectively), high annual survival of mature females (0.64–0.71), projected age-ratios heavily skewed toward adults, and longer generation times. Conversely, a population in grasslands heavily fragmented by cultivation and managed with longer fire-return intervals and moderate grazing (Smoky) initiated nests earlier, had higher nest and brood survival rates (0.16–0.31 and 0.34, respectively), produced significantly larger eggs, and had low annual survival (0.34–0.42) and shorter generation times. A site with intermediate levels of fragmentation, burning and grazing (North) had intermediate demography. Finite population change was more sensitive to changes in adult survival at all sites, but the relative influence of fecundity parameters on projected population change was not similar among study populations. Data indicate that differences in rates of decline among populations were largely due to variation in adult survival mediated by human landscape alteration. Human-mediated changes to grasslands impact the demography and viability of prairie-chicken populations, influence population sensitivities to changes in vital rates, and mediate changes in the life-history strategies of a grassland-sensitive species.
16

Flight characteristics of pen-reared and wild prairie-chickens and an evaluation of a greenhouse to rear prairie-chickens

Hess, Marc Frederick 30 September 2004 (has links)
The introduction of pen-reared Attwater's prairie-chickens (APC, Tympanuchus cupido attwateri) into the wild to supplement existing populations has met with marginal success. Flight characteristics, predator avoidance behavior, and rearing methods are possible factors contributing to post-release mortality of pen-reared birds. To evaluate flight characteristics and predator avoidance behavior of pen-reared APC's released onto the Attwater Prairie Chicken National Wildlife Refuge, flight characteristics and predator avoidance behavior of pen-reared APC's was compared to wild greater prairie-chickens (GPC, T. c. pinnatus) in Minnesota and Kansas using a radar gun and a trained dog. There was no difference (P = 0.134) in flight speed for pen-reared APC and wild GPC. However, wild GPC had greater (P < 0.001) flight distances than did pen-reared APC. Wild GPC and pen-reared APC that had survived in the wild for at least a year flushed at a greater (P < 0.001) distance from an approaching human than did pen-reared APC that had been released for less than 3 months. A trained dog was able to approach closer (P < 0.001) to APC than GPC before birds flushed, and APC did not fly as far as GPC after being flushed by the dog. Pen-reared APC displayed flight endurance deficiencies and were more approachable by humans and a dog before they flushed when compared to wild GPC, which could explain their increased mortality when released into the wild. To determine if APC chicks could be reared without daily human contact, pelleted food, and water in founts, a greenhouse was used to rear chicks in a semi-natural environment. Planted vegetation and commercial insects provided hiding cover and a food source for the APC chicks. An underground heat source provided chick warmth, and water misters and a sprinkler system simulated dew (a water source for chicks) and rain. The greenhouse provided chicks protection from predators and adverse weather conditions (before they could thermo-regulate) while exposing chicks to natural sunlight, day length, and temperature fluctuations. This technique allowed chicks to be reared in a semi-natural environment which reinforced their natural foraging behavior for food and water, and reinforced their hiding and avoidance behaviors, creating a wilder pen-reared bird.
17

Flight characteristics of pen-reared and wild prairie-chickens and an evaluation of a greenhouse to rear prairie-chickens

Hess, Marc Frederick 30 September 2004 (has links)
The introduction of pen-reared Attwater's prairie-chickens (APC, Tympanuchus cupido attwateri) into the wild to supplement existing populations has met with marginal success. Flight characteristics, predator avoidance behavior, and rearing methods are possible factors contributing to post-release mortality of pen-reared birds. To evaluate flight characteristics and predator avoidance behavior of pen-reared APC's released onto the Attwater Prairie Chicken National Wildlife Refuge, flight characteristics and predator avoidance behavior of pen-reared APC's was compared to wild greater prairie-chickens (GPC, T. c. pinnatus) in Minnesota and Kansas using a radar gun and a trained dog. There was no difference (P = 0.134) in flight speed for pen-reared APC and wild GPC. However, wild GPC had greater (P < 0.001) flight distances than did pen-reared APC. Wild GPC and pen-reared APC that had survived in the wild for at least a year flushed at a greater (P < 0.001) distance from an approaching human than did pen-reared APC that had been released for less than 3 months. A trained dog was able to approach closer (P < 0.001) to APC than GPC before birds flushed, and APC did not fly as far as GPC after being flushed by the dog. Pen-reared APC displayed flight endurance deficiencies and were more approachable by humans and a dog before they flushed when compared to wild GPC, which could explain their increased mortality when released into the wild. To determine if APC chicks could be reared without daily human contact, pelleted food, and water in founts, a greenhouse was used to rear chicks in a semi-natural environment. Planted vegetation and commercial insects provided hiding cover and a food source for the APC chicks. An underground heat source provided chick warmth, and water misters and a sprinkler system simulated dew (a water source for chicks) and rain. The greenhouse provided chicks protection from predators and adverse weather conditions (before they could thermo-regulate) while exposing chicks to natural sunlight, day length, and temperature fluctuations. This technique allowed chicks to be reared in a semi-natural environment which reinforced their natural foraging behavior for food and water, and reinforced their hiding and avoidance behaviors, creating a wilder pen-reared bird.
18

Applications of mathematical models to resolving questions in animal behavior, ecology and epidemiology /

Fefferman, Nina H. January 1900 (has links)
Thesis (Ph.D.)--Tufts University, 2005. / Adviser: J. Michael Reed. Submitted to the Dept. of Biology. Includes bibliographical references (leaves 126-135). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
19

Influence of the Conservation Reserve Program and landscape composition on the spatial demographics of prairie grouse in northeastern South Dakota /

Runia, Travis J. January 2009 (has links) (PDF)
Thesis (M.S.)--Wildlife and Fisheries Sciences Dept., South Dakota State University, 2009. / Includes bibliographical references (leaves 74-85). Also available via the World Wide Web.
20

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.

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