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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.
111

Spatio-temporal distribution of white-tailed deer (Odocoileus virginianus) relative to prescribed burns on rangeland in South Texas

Meek, Michael Glenn 15 May 2009 (has links)
Overgrazing and fire suppression has left much rangeland in poor condition for various wildlife species. Prescribed fire is one range improvement practice used to restore degraded wildlife habitat. I determined the effect of prescribed fire on whitetailed deer (Odocoileus virginianus) spatial and temporal distribution, in the presence of cattle grazing. Three 40 ha patches, constituting 10% and 6% of the land area in the lesser and greater Yellow Bluff pasture, respectively, were burned in September 2005. To determine habitat use and distribution of deer relative to these burns 3 bucks and 3 does were netted from a helicopter and fitted with Global Positioning System (GPS) telemetry collars (Lotek™ GPS_3300S) for a period of 30 days during each season. For estimation of spatial distribution of deer, the collars were programmed to take a position fix every hour to reduce problems associated with spatial autocorrelation. For 12 days within this period the collars recorded animal location every 5 minutes to compare habitat use with 6–9 GPS collars (GPS_3300LR) placed on cattle. This allowed me to examine fine-scale movements of deer relative to cattle. Trials were conducted prior to the burn and in each season for one year after the burn. Areas to be burned were not favored by deer. A month after the burn in Fall 2005 there was an increase in use of the burned areas by deer. Deer preference for burned areas fell in Spring and Summer 2006, but in Fall 2006 females dramatically increased their use of the burns. This is possibly an artifact of small sample size and the random selection of individuals. Interaction between deer and cattle was minimal, as they inhabited different areas. When cattle moved within approximately 50 m of a stationary deer the deer was likely to move away. Vegetation measurements showed no significant change in shrub cover and density and a decline in available herbaceous forage on both treatment and control sites in the second year. The lack of vegetative response because of drought conditions was likely the cause of the lack of response by the deer to the burns.
112

Habitat selection and movement patterns of cattle and white-tailed deer in a temperate savanna

Depew, Jarrod Jason 01 November 2005 (has links)
This study investigated the use of high resolution satellite imagery in research involving habitat selection, and movement patterns of white-tailed deer and cattle in a semi-arid landscape. Vegetation classification was developed based on Ikonos satellite imagery that was then used to define habitat selection and characterize movement paths of deer and cattle to allow a better understanding of these 2 species. Pasture attributes were also measured to determine animal distribution throughout the study area in relation to roads, fences, water location, and supplemental feeders. Three cattle and 3 free ranging white-tailed deer were used during 3 trials to test seasonal differences in habitat selection and spatial distribution across the pasture. Ikonos satellite imagery was classified to a final classification accuracy of 83.6%. Seven vegetation classes were defined in the classification with 1 class of bare ground/ herbaceous that represents interspaces between shrub vegetation. Classification accuracy was obtained using a ?? meter buffer to all ground control points increasing the accuracy from 71.29%. All physical pasture attributes were significant to animal distributions in the study area when compared to the random distribution. Roads and water location were most important to cattle during the spring and summer. White tailed deer use of the pasture was more dependent on vegetation characteristics than physical attributes. Both cattle and deer selected habitat patches with a proportionately large percentage of bare-ground/interspaces (>40%). Deer were predominately found in areas containing higher percentages of shrub species, while cattle were found in areas containing a mixture of larger tree species in addition to shrub complexes. Travel velocity and path tortuosity were measured to determine effects of vegetation attributes on animal movements. Both cattle and deer followed fairly linear paths (Fractal Dimension<1.2). Factors contributing to path tortuosity included mean patch size, number patches, and patch fractal dimension. Travel velocity was also measured and compared to vegetation association attributes. Travel velocity was significantly different between seasons for white-tailed deer however cattle and deer comparisons were not significant across the 3 trials. Number of patches, patch fractal dimension, mean patch size, and patch area were significant in the travel velocity model.
113

Spatial and temporal relationships between deer harvest and deer-vehicle collisions at Oak Ridge Reservation, Tennessee

Pierce, Amanda Marie 01 August 2010 (has links)
The Department of Energy Oak Ridge Reservation (ORR) and the nearby adjoining City of Oak Ridge, Tennessee had experienced a rise in deer-vehicle collisions (DVCs) to the point where safety for employees and residents became a concern. I investigated the effect of hunting, land cover, road mileage, season, lunar phase, sex, and change in traffic patterns that coincide with work shifts on DVCs from 1975 - 2008. The study area was divided into grids of 1.5 km² each for administration and data recording by managing agencies. Statistical analyses were performed on the ORR (121 grids) and GIS analyses were performed on the entire study area that included ORR and the city of Oak Ridge (190 grids). The number of DVCs in 1975 was 16 and reached a high of 273 in 1985. Therefore, managers initiated a hunting program in 1985 and recorded deer harvest numbers by grid each year. Deer harvest has been occurring from 1985 until present, except when hunting was cancelled due to security concerns after the September 11 terrorist attacks in 2001. By 2008, the number of DVCs had decreased to 100 per year. When hunting first started in 1985, they harvested 926 deer. By 2008, that number was down to 481. I used GIS mapping to record DVCs, deer harvest per grid, landcover types, and mileage per grid to determine factors affecting DVCs on the smaller landscape. Following the initiation of annual hunts, both the annual deer harvest and the number of DVC’s have fallen, presumably because the overall deer population has declined from high pre-hunting levels. Deer harvest appears to be related to landcover characteristics, as a higher percentage of deer were harvested from forested areas than from other landcover types, as forested areas were most prominent. The months of October, November, and December had the highest DVC numbers. Increased traffic during starting and leaving shift times seem to increase the number of DVCs as well. Lunar phases only seem to significantly increase DVCs during the gestation and fawning seasons. Does are involved more frequently with DVCs than bucks during gestation, fawning and prerut, but not during the rutting season. I expect managers can use this data to guide intensive local management aimed at reducing DVCs by increasing the number of deer harvested and increased public education.
114

Late prehistoric bone marrow extraction : a case study in western Wisconsin /

Pfaffenroth, Jake. January 2009 (has links)
Thesis (B.S.)--University of Wisconsin -- La Crosse, 2009. / Also available online. Includes bibliographical references (p. 26-28).
115

Distributions of the Coues deer in pinyon stands after a wildfire

Barsch, Bob Knight, 1941- January 1977 (has links)
No description available.
116

Pharmacokinetics and tissue withdrawal study of tulathromycin in North American bison (Bison bison) and white-tailed deer (Odocoileus virginianus) using liquid chromatography-mass spectrometry

2014 February 1900 (has links)
Tulathromycin is a macrolide antibiotic approved for use in cattle and swine respiratory disease. Extra-label use of tulathromycin occurs in bison and deer and significant interspecies differences in pharmacokinetics warrant specific investigation in these species. This study involved investigation of the pharmacokinetics of tulathromycin in bison and white-tailed deer following a single 2.5 mg/kg bw subcutaneous injection (n=10) of Draxxin (Pfizer Inc.) to provide important information regarding tulathromycin dosage regimens in these species. As well, tulathromycin distribution and depletion in deer muscle and lung tissues following a 2.5 mg/kg bw subcutaneous injection of Draxxin was investigated to obtain pilot information regarding withdrawal time of tulathromycin in deer. For the pharmacokinetic studies, serial blood samples were collected at baseline and up to 25 days post-injection. Pharmacokinetic parameters were estimated using non-compartmental methods. For the tissue pilot study, deer (n = 2 to 3) were slaughtered at 0, 1, 2, 6, 7, and 8 weeks post-injection. A quantitative analytical liquid chromatography-mass spectrometry method for measuring tulathromycin was developed and validated in bison and deer serum and deer lung and muscle according to international guidelines. Samples were processed by solid-phase extraction. Reverse-phase chromatography was performed by gradient elution. Positive electrospray ionization was used to detect the double charged ion [M+2H]+2 at m/z 403.9 and monitored in selected ion monitoring mode. Tulathromycin demonstrated early maximal serum concentrations, extensive distribution, and slow elimination characteristics in deer and bison. In bison, mean Cmax (195 ng/mL) was lower compared to cattle (300 to 500 ng/mL) and half-life (214 hours) longer (cattle, 90 to 110 hours). In deer, mean Cmax (359 ng/mL) is comparable to cattle, but half-life (281 hours) was much longer. Tissue distribution and clinical efficacy studies are needed in bison to confirm extensive distribution of tulathromycin into lung and the appropriate dosage regimen. Tulathromycin was extensively distributed to deer lung and muscle, with tissue levels peaking within 7 to 14 days after injection. Drug tissue concentrations were detected 56 days after treatment, longer than the established withdrawal time of 44 days in cattle. This prolonged drug concentration in the tissue is supportive for the administration of tulathromycin as a single injection therapy for treatment of respiratory disease of deer. While more study is needed to establish a recommended withdrawal time, the long serum and tissue drug half-life and extensive interindividual variability in tissue levels suggests a withdrawal period well beyond 56 days may be required in deer.
117

Habitat selection by sympatric ungulates in an agricultural landscape : implications for disease transmission and human-wildlife conflict

2013 January 1900 (has links)
As areas of agricultural production expand worldwide, complex zones of wildlife-agriculture interface present numerous benefits and challenges to farmers and wildlife managers. In western Canada, free-ranging elk (Cervus canadensis), mule deer (Odocoileus hemionus), and white-tailed deer (Odocoileus virginianus) make frequent use of cereal, oilseed, and pulse crops. However, cervid use of annual crops presents substantial socio-economic concerns for producers. Additionally, use of crops may facilitate cervids co-mingling and increase the risk of intra- and inter-specific transmission of chronic wasting disease (CWD). The purpose of my thesis research was to determine the key environmental factors influencing the selection of agricultural crops by elk, white-tailed deer, and mule deer, analyze overlap in species’ selection, and develop predictive models to identify the spatial distribution of crop damage risk. In this study, I analyzed 19,069 damage claims paid by Saskatchewan Crop Insurance Corporation to Saskatchewan farmers for confirmed losses to annual crops (cereals, oilseeds, pulses) from 2000-2012 by elk, mule deer, and white-tailed deer. These data were used to conduct species-specific ecological niche factor analyses (ENFAs), which relate habitat variables within damaged sites to that of the surrounding landscape. The key habitat variables influencing selection of annual crops were then incorporated into resource selection probability function (RSPF) models. These models characterize and predict the probability of crop damage by elk, mule deer, and white-tailed deer, and each possible dual species combination. By integrating damage probability values and historical monetary values of regional crop production, I evaluated the risk of annual crop damage by each of the three species, and dual species combinations, across all sections of agricultural land in Saskatchewan. The ENFAs revealed that elk and white-tailed deer selected for areas where a high proportion of farmland is seeded to oats, barley, canola, and alfalfa, while avoiding areas farther from protected areas, with a high density of paved or unpaved roads and a high proportion of open grassland. Alternately, mule deer favoured open grasslands, shrublands, and areas with a greater density of streams or water bodies, while avoiding areas where a high proportion of farmland is seeded to oats, canola, flaxseed, wheat, and barley. Areas at highest risk for annual crop damage by elk bordered the northern edge of the study area; mule deer damage risk was highest in south-western and central Saskatchewan; while white-tailed deer damage risk was highest in north-eastern and north-central areas of the province. Identifying these specific associations between landscape variables, rates of crop damage, and associated species overlap may provide an important opportunity for agencies to develop cooperative management strategies to efficiently allocate mitigation resources. Efforts to prevent the selection of cereal, oilseed, and pulse crops by free ranging elk, mule deer, and white-tailed deer in Saskatchewan could prove to be a valuable step in not only minimizing crop damage and maintaining wildlife tolerance in rural communities, but also in managing the spread of chronic wasting disease throughout western Canada.
118

Ecology and management of white-tailed deer (Odocoileus virginianus) and mule deer (O. hemionus) of east-central Alberta in relation to chronic wasting disease

Habib, Thomas J Unknown Date
No description available.
119

Factors driving range expansion of white-tailed deer, Odocoileus virginianus, in the boreal forest of northern Alberta, Canada

Dawe, Kimberly Louise Unknown Date
No description available.
120

Ecology and management of white-tailed deer (Odocoileus virginianus) and mule deer (O. hemionus) of east-central Alberta in relation to chronic wasting disease

Habib, Thomas J 11 1900 (has links)
Chronic wasting disease (CWD) is a fatal pathogen affecting white-tailed and mule deer in east-central Alberta, and I addressed two current limitations of CWD management. First, to improve precision and accuracy of density estimates obtained from aerial surveys, I evaluated alternative survey designs and developed a model to correct for undetected deer due to low snow cover, small group sizes, and deer inactivity. Surveys stratified by resource selection functions showed the greatest improvement in precision compared to currently employed designs. Second, I addressed how density and landscape features affect contact rates among deer, a major component of CWD transmission. Contact rates increased as a saturating function of density, and were highest in regions where deer habitat was limited. My results will allow managers to better plan and evaluate management actions such as herd reductions, and underscore the need for developing spatially-explicit models to understand CWD spread in heterogeneous environments. / Ecology

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