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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

Impact of health, husbandry, and conservation research on glucocorticoid concentrations in Atelopus species

Cikanek, Shawna January 1900 (has links)
Master of Science / Department of Clinical Sciences / James W. Carpenter / In many species, temporary increases in glucocorticoids (GC) can be used to identify changes in adrenal activity in response to acute stressors. For this research, GC metabolites were identified in fecal extracts from various Atelopus species. The objectives were to identify possible correlates between GCs and health status, assess the impact of husbandry protocols on adrenal activity, and evaluate the sub-lethal effects of antifungal bacteria used for protection of frogs against the chytrid fungus (Batrachochytrium dendrobatidis; Bd). The first study examined whether fecal GC concentrations can be correlated with animal health and behavior changes in a captive setting. Atelopus zeteki with varying degrees of dermatitis were categorized based on the severity of their skin abnormalities and GC metabolite concentrations were analyzed to detect correlations between severity of disease and GC metabolite concentrations. Similarly, behaviors that may indicate elevated stress levels (e.g., time spent in hide) were analyzed to detect correlation between disease and behavior changes. There was no correlation between fecal GC metabolites and health status of the animal or between health status and amount of time spent in hide. The second study established ex situ colonies of two Panamanian frog species, Atelopus certus and Atelopus glyphus, to determine how male group size affects behavior and GC levels. When housed in groups of eight, animals initially had elevated GC concentrations and interacted aggressively, but these instances declined substantially in the first 2 weeks of being housed together. Thus, captive Atelopus populations can be housed in same-sex enclosures without causing sub-lethal stress on the individuals involved. The third study examined the ability of antifungal bacterium from Central America to propagate on Atelopus skin as a preventative treatment for Bd and the sub-lethal effects of each bacteria species on adrenal function based on GC analysis. Four species of bacteria (Pseudomonas sp., Pseudomonas putida, Chryseobacterium indolgenes, and Stenotrophomonas maltophili) were found to be successful Bd inhibitors in vitro. There were no detectable effects of bacterial exposure with GC metabolite concentrations over time for any of the treatments assessed.
2

Efficacy of native grassland barriers at limiting prairie dog dispersal in Logan county, Kansas

Eddy, Zachary January 1900 (has links)
Master of Arts / Department of Geography / J. M. Shawn Hutchinson / Prairie dogs (Cynomys spp.) are social, ground-dwelling rodents native to North American short- and mixed-grass prairie. They are also the main prey of the Federally-endangered black-footed ferret (Mustela nigripes). At the same time, prairie dog colonization is highly opposed by most agricultural landowners. Therefore nonlethal population management techniques must be investigated. This paper presents the results of research on the effectiveness of ungrazed vegetative barriers composed of native plants at limiting prairie dog dispersal away from a ferret reintroduction site in northwest Kansas. Data was collected on barrier quality and condition as well as estimates of population densities of immigrant prairie dogs, dispersing through the vegetative barrier to reoccupy previously extirpated colonies on properties surrounding the ferret reintroduction site. Using strip transects and aboveground visual counts to estimate population densities and visual obstruction ranking techniques to sample barrier condition, statistical analysis of the data indicated that while barrier condition increased over time, it was not effective at limiting prairie dog emigration from the black-footed ferret reintroduction site.
3

Benefits of the state acres for wildlife enhancement practice for bird populations in Kansas

Thomas, Alaina D. January 1900 (has links)
Master of Science / Division of Biology / Brett K. Sandercock / Grassland birds have experienced population declines worldwide from habitat degradation caused by conversion to agriculture and recent intensification of land use, including increased use of fertilizer, fossil fuels, and irrigation. The U.S. Department of Agriculture, Conservation Reserve Program (CRP) includes initiatives targeting wildlife enhancement to mitigate ongoing declines in grassland bird populations. The newest CRP practice, State Acres for Wildlife Enhancement (SAFE), was designed to restore vital habitats for high priority wildlife species throughout the United States. Our objective was to assess the potential benefits of SAFE for upland gamebirds and grassland songbirds in Kansas. We monitored lands enrolled in SAFE to estimate bird density based on field scale and landscape scale characteristics. Our study was conducted in three ecoregions: Smoky Hills (4 counties), Flint Hills (3 counties), and the High Plains (3 counties). We surveyed 121 SAFE fields and 49 CRP fields from 2012 – 2013. Northern Bobwhite density was negatively associated with percent litter within survey fields. Ring-necked Pheasant density differed among ecoregions, and was positively associated with percent bare ground in the High Plains, but negatively associated with field age in the Smoky Hills. Mourning Dove density differed among ecoregions, and was negatively associated with percent forb in the High Plains, and positively associated with percent grassland in the Smoky Hills. In the Flint Hills, Mourning Doves were negatively associated with CRP fields and large fields. Brown-headed Cowbirds were positively associated with percent forbs. Amount of CRP surrounding survey locations was positively associated with bird density through the entire range for Grasshopper Sparrows, Dickcissels, and Lark Buntings, and in the High Plains for Western Meadowlarks. Percent woodland had negative effects on Western Meadowlarks in the Smoky Hills, whereas percent cropland had negative effects on Eastern Meadowlarks statewide. CRP positively affected abundance of four of our species, whereas percent cropland and woodland negatively affected others. Thus, the amount of set-aside lands enrolled in SAFE could be important for grassland bird populations. SAFE and CRP supported equal numbers of Northern Bobwhites and Ring-necked Pheasants, suggesting SAFE provides benefits for target species of upland gamebirds.
4

Patterns and pathways of lead contamination in mottled ducks (Anas fulvigula) and their habitat

Kearns, Brian Vance January 1900 (has links)
Doctor of Philosophy / Department of Biology / David A. Haukos / Mottled ducks (Anas fulvigula) are dabbling waterfowl species native to coastal wetlands of the Gulf of Mexico of the United States and Mexico. Although closely related to common waterfowl species such as the mallard (A. platyrhynchos) and American black duck (A. rubripes), the mottled duck exhibits unique behavior, mainly in its life history as a non-migratory species. As such, because of population declines caused by predation, habitat destruction, and environmental contaminants, this species requires specialized conservation concerns and species-specific management to protect population numbers. The goal of this study was to assess ongoing effect of observed lead (Pb) contamination and exposure issues in mottled ducks and their habitats, which I achieved by conducting assessments that will provide managers habitat and organism level metrics to detect and mitigate lead in mottled ducks and their environments. My field study was conducted at the Texas Chenier Plain National Wildlife Refuge Complex (TCPC), which was the area of greatest mottled duck density on the Texas Coast. I first created a body condition index to provide managers a tool to monitor population health, and a proxy for lead exposure and avian health without destructively sampling individuals. I then used presence-only maximum entropy (MaxENT) and multivariate statistical modeling procedures in conjunction with mottled duck movement data to elucidate sets of habitat conditions that were conducive to predicting the occurrence of mottled ducks and environmental lead “hot spots”. MaxENT analyses suggested that lead in the top portion of the soil column is similarly related to all environmental variables considered, may be increasingly available after large-scale environmental disturbances. Lack of variation in coarse-scale habitat use between breeding and non-breeding seasons may further point to a food-based exposure pathway for lead as mottled ducks switch from an invertebrate to plant diet, either as a result of changing age classes or normal adult phenology, during the period of increased lead exposure. Using stable isotope ratio analysis, I then tested environmental samples of soil and vegetation as well as mottled duck blood to determine isotopic signatures that were consistent with particular sources of lead deposition (e.g., lead shot pellets, leaded fossil fuel combustion, industrial effluents). Comparisons suggested a great deal of similarity to lead shot reference values in vegetation and blood samples, especially in blood samples with higher concentrations of lead present. Last, I conducted a formal Ecological Risk Assessment (ERA) procedure to quantify the risk to mottled ducks from lead exposure in their current habitat and direct managers towards effective mitigation and habitat management strategies to reduce exposure in the future. One scenario suggested that mottled ducks were at greatest risk from eating an invertebrate-based diet, but lead content values at the TCPC suggest that a plant-based diet may provide a higher lead exposure risk for mottled ducks, depending on true levels of bioavailability in environmental media. Overall, I determined that mottled ducks experience greatest lead exposure risk from lead shot pellets on the TCPC or in nearby habitat, while potentially also experiencing low levels of exposure from several other sources. Additionally, management efforts that focus on plants that do not provide food resources for mottled ducks as a potential environmental sink for lead contamination, such as phytoremediation, may prove effective in reducing the overall lead load from historical activities that likely deposited much of the lead in this ecosystem.
5

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.
6

Evaluation of wildlife food plot seed mixes for Kansas

Tajchman, Alan J. January 1900 (has links)
Master of Science / Horticulture, Forestry, and Recreation Resources / Peg McBee / Three wildlife seed mixes were tested, Perfect Plot (BioLogic), Rack Force (Evolved Harvest), and Bird and Buck Whitetail and Gamebird mix (Star Seed). Two methods of research were conducted, (1) a food plot monitoring field study, and (2) a seed germination laboratory test. Food plots were planted in northwest (Jennings) and northeast (Manhattan) Kansas. Single season occupancy models from Program MARK were used to determine plot usage and preference of the seed mixes. Feeding patterns were analyzed from two locations targeting white-tailed deer (Odocoileus virginianus). Camera trap data were also analyzed for raccoon (Procyon lotor), wild turkey (Melagris gallopavo), and coyote (Canis latrans). During the summer 2014, the Bird and Buck mix retained the greatest amount of desirable vegetation, compared to the Rack Force and Perfect Plot mixes, which exhibited intermediate and relatively poor stand condition, respectively. White-tailed deer were documented at 100% occupancy using all (i.e., 100%) plots of all three mixes in Manhattan and Jennings, Kansas. In Manhattan, a significant increase in feeding events was observed for the months of July (45% of days) and August (50% of days) compared to the month of June (34% of days; p < 0.02). In contrast, deer feeding events in Jennings declined from 67% and 55% of days in June and July, respectively, to only 18% of days in August (p < 0.001). After initially having establishment issues among all three mixes, a laboratory study was initiated comparing the germination rates of each seed mix. Ten 1-gram random samples of each seed mix were tested in complete darkness at a constant 25-30°C for 25 days. When comparing daily germination rates of the seeds in the mixes, peak germination for all mixes (p < 0.0001) occurred on days 5-10 and 12-14. A single expected germination rate of similar plant types (i.e. alfalfa, clover, chicory, grasses) was computed from the seed tag, and then compared to the observed proportion of total seeds sampled that germinated. Bird and Buck recorded the highest germination, 79%, only 0.5% less than the expected overall germination. Perfect Plot and Rack Force recorded germination rates of 49% and 52%, which respectively, were 7% and 11% less than was expected.
7

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.
8

Lesser prairie-chicken reproductive success, habitat selection, and response to trees

Lautenbach, Joseph Mark January 1900 (has links)
Master of Science / Department of Biology / David A. Haukos / The lesser prairie-chicken (Tympanuchus pallidicinctus) is a species of prairie grouse native to the southwest Great Plains. Population declines and threats to populations of lesser prairie-chickens led U.S. Fish and Wildlife Service to list the species as “threatened” under the protection of the Endangered Species Act in May 2014. Lesser prairie-chickens are found within three distinct ecoregions of Kansas and Colorado and portions of the species’ range are affected by tree encroachment into grasslands. The effect of trees on lesser prairie-chickens is poorly understood. I evaluated habitat selection and reproductive success and across the northern portion of the species’ range. I captured female lesser prairie-chickens within the three different ecoregions in Kansas and Colorado to track nest and brood survival and measure nest and brood habitat. My findings show that there are regional and annual variations in nest and brood survival. Mean nest survival during 2013 and 2014 was estimated to be 0.388 (95% CI = 0.343 – 0.433) for a 35-day exposure period. Brood survival during 2013 and 2014 was estimated to be 0.316 (95% CI = 0.184 – 0.457) for 56 days. Chick survival was the lowest during the first week of life and is probably a limiting factor for population growth. Chick and brood survival decreased as Julian hatch date increased. Across the northern portion of the species’ range, females consistently select visual obstruction between 2-3 dm. Vegetation at the nest changes between regions and years to reflect environmental and regional conditions. Broods consistently selected habitats with greater percent cover of forbs than was expected at random across all study sites. Broods also selected against areas of bare ground. The threshold of lesser prairie-chicken use was 2 trees/ha throughout the year. No nests were located within areas with greater densities. Lesser prairie-chickens had a greater probability of use at greater distances from trees and at lower tree densities. To provide adequate nesting habitat managers should provide 2-3 dm of visual obstruction. Providing forb cover with visual obstruction between 2.5-5 dm near nesting habitat should provide adequate habitat for broods. Removing trees in core habitats and expand removal efforts outward should expand potential habitat for lesser prairie-chickens.
9

Restorative urban design: toward a design method for mitigating human impacts on the natural environment through urban re/development

Toros, Tulu January 1900 (has links)
Doctor of Philosophy / Department of Environmental Design & Planning Program / Lee R. Skabelund / The Restorative Urban Design (RUD) calls for a new urban design and planning approach targeting environmentally responsible re/development of urbanized areas through ecologically responsive impact mitigations. If implemented in a systematic manner, such re/developments can help move urban areas toward the successful restoration of the natural environment of which they are an inseparable part. The RUD model advocates more rigorous assessment and mitigation of urban impacts by carefully evaluating the environmental performance of urban re/developments within five primary dimensions: Atmosphere (emissions, pollutants, ozone depletion); Hydrosphere (stormwater, domestic water, wastewater); Lithosphere (land use, land cover, food and wastes); Ecology (habitat resilience, biodiversity, population and resources); and Energy (renewability, reduction and efficiency, transportation). The model relies on a scenario-comparison process in order to evaluate and optimize the performance of urban re/development projections through four critical scenarios, which are respectively: 1) Natural Baseline (NBASE); 2) Historic Progression (HPROG); 3) Trajectory Forecast (TFORE); and 4) Restorative Projection (RPROJ). The RUD Case Study illustrates how the principles and strategies of Restorative Urban Design can be applied specifically to a typical (densely developed) urban area, namely River North District in Chicago Metropolitan Area. The case study focuses exclusively on mitigation of a single critical human impact on the natural environment: Anthropogenic CO₂ Emissions. The case study focuses on the design assumptions by which the restorative urban re/development scenarios might exceed beyond the full mitigation of emissions into the global remediation by 2040. The restorative projections illustrate that only a certain portion of emissions can be effectively mitigated onsite (5 to 55%), and that the remainder of projected emissions (45 to 95%) need to be mitigated offsite in order to achieve the necessary sequestration and storage. The restorative research suggests that the mitigation of major human impacts on the natural environment – not only CO₂ emissions but also other major impacts – are likely to require significant urban transformations. Moving beyond the strategies of preservation and/or conservation, the restorative approach asserts that comprehensive environmental restoration is achievable if urban impacts are adequately estimated and then entirely mitigated onsite as well as offsite through a systematic process of urban re/development.

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