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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.
231

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.
232

Impacts of oil and gas development on sharp-tailed grouse on the Little Missouri National Grasslands, North Dakota /

Williamson, Ryan M. January 2009 (has links) (PDF)
Thesis (M.S.)--Wildlife and Fisheries Sciences Dept., South Dakota State University, 2009. / Includes bibliographical references (leaves 91-100). Also available via the World Wide Web.
233

Prey selection and kill rates of cougars in northeastern Washington

Cruickshank, Hilary Stuart. January 2004 (has links) (PDF)
Thesis (M.S.)--Washington State University, 2004. / Title from PDF title page (viewed on May 22, 2005). Includes bibliographical references.
234

Advantages of habitat selection and sexual segregation in mule and white-tailed deer /

Main, Martin Benjamin. January 1994 (has links)
Thesis (Ph. D.)--Oregon State University, 1994. / Typescript (photocopy). Includes bibliographical references (leaves 108-121). Also available on the World Wide Web.
235

Properties of enzymes from mammalian hibernators; structure, function, relationships.

Thatcher, Bradley John, Carleton University. Dissertation. Biology. January 1997 (has links)
Thesis (Ph. D.)--Carleton University, 1997. / Also available in electronic format on the Internet.
236

ECOLOGY AND BEHAVIOR OF WHITE-TAILED DEER IN SOUTHERN ILLINOIS: SURVIVAL, CONTACT RATES, AND IMPACT OF LOCALIZED REMOVAL

Tosa, Marie Irene 01 May 2015 (has links)
An understanding of the ecology and behavior of white-tailed deer (Odocoileus virginianus) is necessary for proper conservation and management, especially in the face of emerging infectious diseases. The objectives of my study were to estimate juvenile survival, compare methods of quantifying contact rates (simultaneous GPS locations vs. proximity loggers [PLs]), and investigate the impact of group depopulation on contact rates of remnant adult female and juvenile deer. To achieve these goals, I captured, radiotracked, and monitored adult female and juvenile white-tailed deer in southern Illinois during 2011-2014. Survival analysis of juveniles revealed that main causes of mortality were capture related and predation, though some dead animals also showed signs of hemorrhagic disease. Comparison between simultaneous GPS locations and PLs showed evidence that deer coming within the general vicinity of each other are less likely to come in close contact if they are in neighboring social groups than deer whose home ranges overlap little, if at all. Finally, experimental removal of group members caused few if any remnant adult females to alter their contact rates or space-use, but caused remnant juveniles to have lower space-use fidelity compared to control deer and to increase their direct contact rates with other groups temporarily. Using these results, I discuss the large effects that severe weather events can have on juvenile survival, the importance of social structure on the potential transmission of disease agents among female and juvenile deer, and the difference between adult females and juvenile deer in their need for social interactions. My research provides ecologists, wildlife biologists, and managers with valuable information concerning the potential impacts of the environment, infectious diseases, and management strategies on white-tailed deer populations.
237

Interactions between white-tailed deer and vegetation in southern Illinois

Leeson, Ryan Elizabeth 01 May 2018 (has links)
White-tailed deer (Odocoileus virginianus) have considerable impacts on woody and herbaceous vegetation. Many oak-hickory forests in the eastern U.S. are experiencing a lack of oak (Quercus) and hickory (Carya) regeneration, with deer being a likely culprit. Furthermore, few have studied deer use of different herbaceous food plot mixtures. I addressed these gaps in the literature by assessing deer impacts on forest and herbaceous vegetation in southern Illinois. I established 150 paired plots (enclosed and control) in June 2015 and measured 25 habitat variables to assess impacts of deer herbivory from August 2015 to August 2016. Oak seedlings were present more often and in higher numbers within enclosed plots (F1,299 = 6.25, P < 0.050 and F1,387 = 4.50, P < 0.050, respectively). There were no differences in the height of oak seedlings or the presence, number, or height of hickory seedlings in enclosed versus control plots (F1,53 = 0.010, P = 0.938; F1,299 = 0.850, P = 0.357; F1,267 = 1.16, P = 0.282; and F1,15 = 0.030, P = 0.855; respectively). During September-November 2015, I counted and marked fallen acorns within 50 random paired plots; the number of acorns discovered or lost did not differ between enclosed and control plots (F1,94 = 0.310, P = 0.578 and F1,8 = 0.120, P = 0.736, respectively). I suggest managers incorporate potential deer impacts when designing management plans to best encourage oak regeneration. During September-November 2015, I established 16 food plots (half tilled; each 0.05 ha in size), planted to 4 food plot types. I compared Big Tine Buck Brunch, Evolved Harvest Throw & Gro, Antler King No Sweat, and a food plot mixture that I created. I measured deer use via 2 methods: vegetation growth in exclosures versus control (i.e., unfenced) areas and camera traps. Deer used all 4 food plot mixtures (n = 292 – 2,522 pictures/plot over 9 weeks), having a negative impact on mean vegetation height outside of exclosures (F3,1148 = 6.71, P < 0.001). Analysis of camera data indicated that deer did not preferentially use any one food plot mixture over the others (F3,12 = 0.090, P > 0.050). There also was no difference in the proportion of deer pictured in the process of eating within each food plot mixture (F3,12 = 0.592, P > 0.050). I suggest any of these 4 food plot varieties could be planted by a hunter or wildlife manager in the Midwest and observe similar use by deer.
238

Ecological Significance and Underlying Mechanisms of Body Size Differentiation in White-tailed Deer

Barr, Brannon 05 1900 (has links)
Body size varies according to nutritional availability, which is of ecological and evolutionary relevance. The purpose of this study is to test the hypothesis that differences in adult body size are realized by increasing juvenile growth rate for white-tailed deer (Odocoileus virginianus). Harvest records are used to construct growth rate estimates by empirical nonlinear curve fitting. Results are compared to those of previous models that include additional parameters. The rate of growth increases during the study period. Models that estimate multiple parameters may not work with harvest data in which estimates of these parameters are prone to error, which renders estimates from complex models too variable to detect inter-annual changes in growth rate that this simpler model captures
239

A Study of the Relationship Between Plains Sharp-Tailed Grouse Nest Site Selection and Survival and Ecological Site Descriptions in the Northern Plains

Klostermeier, Derek Wade January 2019 (has links)
Nest site selection and nesting success of plains sharp-tailed grouse were examined on the Grand River National Grassland in South Dakota during the nesting season from 2009-2012. We used conditional logistic regression to assess vegetation production, ecological site description, and landscape position on nest site selection. Two competing models regarding nest site selection: top model consisted of non-native forbs and native cool-season grasses, second best model included all grass and forb. Nine ESDs were used for nesting; loamy and clayey ecological sites most frequently used and produced the highest standing crop. Most frequent observed nest site State were Annual/Pioneer Perennial and Introduced and Invaded Grass. Top model for nest daily survival rates included litter, second-best model included ESD; second-best model showed negative effect for nests initiated in thin claypan, limy backslope, and sandy ecological sites. Based on daily survival estimate and 23-day incubation period, nests were 59% successful.
240

Portfolio risk measures and option pricing under a Hybrid Brownian motion model

Mbona, Innocent January 2017 (has links)
The 2008/9 financial crisis intensified the search for realistic return models, that capture real market movements. The assumed underlying statistical distribution of financial returns plays a crucial role in the evaluation of risk measures, and pricing of financial instruments. In this dissertation, we discuss an empirical study on the evaluation of the traditional portfolio risk measures, and option pricing under the hybrid Brownian motion model, developed by Shaw and Schofield. Under this model, we derive probability density functions that have a fat-tailed property, such that “25-sigma” or worse events are more probable. We then estimate Value-at-Risk (VaR) and Expected Shortfall (ES) using four equity stocks listed on the Johannesburg Stock Exchange, including the FTSE/JSE Top 40 index. We apply the historical method and Variance-Covariance method (VC) in the valuation of VaR. Under the VC method, we adopt the GARCH(1,1) model to deal with the volatility clustering phenomenon. We backtest the VaR results and discuss our findings for each probability density function. Furthermore, we apply the hybrid model to price European style options. We compare the pricing performance of the hybrid model to the classical Black-Scholes model. / Dissertation (MSc)--University of Pretoria, 2017. / National Research Fund (NRF), University of Pretoria Postgraduate bursary and the General Studentship bursary / Mathematics and Applied Mathematics / MSc / Unrestricted

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