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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.
71

Deer preference for corn hybrids and husbandry practices during the growing season /

Delger, Joshua A. January 2009 (has links) (PDF)
Thesis (M.S.)--Wildlife and Fisheries Sciences Dept., South Dakota State University, 2009. / Includes bibliographical references. Also available via the World Wide Web.
72

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 John. January 2010 (has links)
Thesis (M. Sc.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on July 23, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Ecology, Department of Biological Sciences, University of Alberta. Includes bibliographical references.
73

Estimating Relative Abundance of White-tailed and Red Brocket Deer on the Western Slope of the Panama Canal Based on Photo Analysis

Ashmore, Joshua Ross 01 December 2009 (has links)
In 2004, the government of Panama created Ecoparque Panama with the aim of conserving unique habitat and curbing urbanization on the western slope of the Panama Canal. A lack of baseline ecological research in the area prompted the Panamanian National Environmental Authority and the U.S. Forest Service International Institute of Tropical Forestry to fund a camera-trap study to catalog and determine relative abundance of predator and prey species in the Panama Canal region. These infrared-triggered camera-traps allowed researchers to study elusive wildlife that may otherwise remain undetected. Using techniques adapted from previous research, infrared and motion-triggered camera-traps were purposively placed in the 4 km2 Ecoparque (U.S. Forest Service spelling: Eco-Park) Panama study area to gather data on two cervid species, white-tailed deer (Odocoileus virginianus) and red brocket deer (Mazama americana). The study was conducted over a five month period (December 2005-April 2006). Data collected were analyzed using SPSS and Stastix statistical software. Results in the form of inferred relative abundances and densities show that populations currently appear to be within the local carrying capacity. Cervid management recommendations of this study include the continued moratorium on deer hunting and strengthening of the legal protection of the red brocket deer. Given the lack of previous data, the conclusions drawn from this preliminary study will be the foundation for future research in Panama.
74

Individual-based modeling of white-tailed deer (Odocoileus virginianus) movements and epizootiology

Kjaer, Lene Jung 01 August 2010 (has links)
White-tailed deer (Odocoileus virginianus) are important game mammals and potential reservoirs of diseases of domestic livestock, so diseases of deer are of great concern to wildlife managers. In many situations, models can be useful for integrating existing data, understanding disease transmission patterns, and predicting effects on host populations. Individual-based modeling (IBM) has become more commonplace in ecology as a tool to link individual behavior to population dynamics and community interactions, especially for gauging the effects of management actions. Spatially explicit IBMs are especially useful when ecological processes, such as disease transmission, are affected by the spatial composition of the environment. I developed a spatially explicit IBM, DeerLandscapeDisease (DLD), to simulate direct and indirect disease transmission in white-tailed deer. Using data from GPS-collared deer in southern Illinois, I developed methods to identify habitats and times of high contact probability. I parameterized movement models, for use in DLD, using field data from GPS-collared deer in both southern and east-central Illinois. I then used DLD to simulate deer movements and epizootiology in two different landscapes: a predominantly agricultural landscape with fragmented forest patches in east-central Illinois and a landscape dominated by forest in southern Illinois. Behavioral and demographic parameters that could not be estimated from the field data were estimated using published literature of deer ecology. I assumed that bioavailability of infectious pathogens deposited in the environment decreased exponentially. Transmission probabilities were estimated by fitting to published trends in infection prevalence, assuming that infection probability during an encounter was equal for all age classes, so infection prevalence varied with sex- and age-specific behavior. DLD simulations of chronic wasting disease epizootiology demonstrated significant effects of landscape structure, social behavior, and mode of transmission on prevalence, emphasizing the importance of spatial, temporal and behavioral heterogeneity in disease modeling. These results demonstrate the utility of IBMs in incorporating spatio-temporal variables as well as animal behavior when predicting and modeling disease spread.
75

Home-range fidelity and the effect of supplemental feeding on contact rates between white-tailed deer in southern Illinois

Rustand, Matthew Clifton 01 May 2010 (has links)
White-tailed deer (Odocoileous virginianus) are an important game animal and provide intrinsic value to many people. However, disease has become of great concern within white-tailed deer populations. Frequency of contract drives the establishment and spread of infectious diseases among susceptible hosts. Supplemental feed provided to increase white-tailed deer survival or create hunting opportunities, as well as bait stations to aid in capture of deer, may increase contact opportunities and disease transfer. My objective was to quantify the effects of bait sites on indirect contact between deer. I examined data from global positioning system (GPS) collars placed on 27 deer near Carbondale, Illinois, USA, from 2002 to 2005. Location data from GPS collars were used to ensure that I quantified contacts between deer in separate social groups, based on the volume of intersection of their spatial utilization distributions and correlation of movements. I matched 35 bait site locations and control sites not containing bait based on local land cover composition. Pairwise indirect contacts between deer were tabulated within a 10, 25, 50, 75, or 100-m buffer around each bait and control site. Indirect contact frequencies between bait and control sites were compared using mixed-model Poisson regression with deer pair as a random-effect variable and bait, joint utilization distribution (JUD), and year as fixed-effect variables. Contact frequencies did not differ significantly (P<0.05) between bait sites and control sites at any buffer distance, implying that small bait piles used to capture deer have minimal effect on contact frequencies. However, the effect of more consistent and greater quantities of food distributed during supplemental feeding programs should be studied further to determine its impact on contact rates and spatial distribution of deer. Understanding the spatial distribution of white-tailed deer is important to implement effective disease and population management within localized areas. The objective of this study was to measure the home-range fidelity of female deer in an exurban deer herd in southern Illinois. I compared location data of 7 deer that had been collected in 2004-2005 and 2008. I used the volume of intersection (VI) and percent of home range overlap to statistically compare the two annual home ranges for each deer. Deer were located used ground-based radiotelemetry and home ranges were characterized using a fixed kernel utilization distribution. Comparing home ranges between years, the mean VI was 0.45 with little variation (range 0.35-0.55). I found the mean percent overlap of 50% isopleths to be 47.1% (range 31.3-71.7%) and the mean overlap of 95% isopleths to be 62.0% (range 44.3-68.6%). My results indicate that female white-tailed deer on our study area showed strong home-range fidelity, which could permit disease and population management by removing deer and reducing local deer densities.
76

ECOLOGICAL AND SOCIETAL IMPACTS OF SUBURBAN WHITE-TAILED DEER: A CASE STUDY IN THE CHICAGO METROPOLITAN AREA

Urbanek, Rachael Elizabeth 01 May 2012 (has links)
Many natural resource agencies are managing white-tailed deer (Odocoileus virginianus) populations in suburban areas and require information about deer populations, deer impacts on vegetation, and human preferences toward deer and deer management to support decision making. My study based in the Chicago Metropolitan Area during 2007-2011, utilized a multi-faceted approach to investigate common obstacles in suburban deer management. In my findings, I discuss the need for managers to examine suburban deer populations and management issues at a broader scale (i.e., countywide versus single community) and the promotion of proactive deer management in lieu of the conventional paradigm of beginning management only when deer populations have become overabundant. Discussion topics include practicality and costs of deer density estimation and herbivory monitoring techniques over multiple plant communities and numerous study sites. In addition, I illustrate how a comprehensive human dimensions survey can identify determinants that contribute to the public's perceptions of deer density and assess the acceptability, conflict, and beliefs regarding deer management methods. Lastly, I describe the relationship between landscape characteristics and deer density; this information can be utilized to determine suburban lands that may be prone to high deer densities and inform land management practices. My work provides suburban natural resource managers with techniques to identify management practices supported by their public constituents and information useful for managing deer populations.
77

ECOLOGY AND MANAGEMENT OF WHITE-TAILED DEER IN AN AGRICULTURAL LANDSCAPE: ANALYSES OF HUNTER EFFICIENCY, SURVEY METHODS, AND ECOLOGY

Anderson, Charles Wayne 01 December 2010 (has links)
Current research is necessary to focus management of white-tailed deer (Odocoileus virginianus) in the agricultural Midwest, especially given the novel presence of chronic wasting disease in the region. My objectives were to: 1) examine the potential effects of weather and row-crop harvest on daily harvest of white-tailed deer by archery, and individual hunter variables (e.g., age, weapon preference, preference of hunting method) on individual hunter efficiency and success in 2 regions of Illinois (i.e., east-central and southern Illinois); 2) estimate white-tailed deer densities using direct (i.e., spotlighting deer from road transects) and indirect (i.e., counting pellet groups on randomly-placed transects) techniques across 3 study areas in the midwestern U.S.; 3) quantify sex, age, and season-specific survival and dispersal rates of white-tailed deer in east-central Illinois; and 4) assess habitat selection of white-tailed deer during the summer months in east-central Illinois. Knowledge of factors affecting hunter efficiency and success is vital given current trends in hunter attitudes and behaviors that are leading to a reduction in the efficacy of white-tailed deer hunting as a population management tool nationwide. Numerous techniques of density estimation for white-tailed deer have been developed, including aerial surveys, mark-recapture or resight methods, pellet counts, and thermal infrared imaging surveys. Distance sampling has shown great potential for estimating white-tailed deer density at a reduced cost relative to traditional survey techniques and may be useful within the agriculturally-dominated Midwest. Survival and dispersal rates are pertinent model parameters when examining chronic wasting disease (CWD) geographic spread. Structural changes in agricultural landscapes are frequent (i.e., temporally) and ecologically abrupt (i.e., spatially) due to crop harvest and rotation and human development. Providing sex-specific data on site selection would benefit agencies and private land owners by allowing compartmental focus for selective management strategies for either male or female white-tailed deer. Following the 2006 hunting season, I queried white-tailed deer hunters regarding factors potentially affecting hunter efficiency and success in east-central and southern Illinois using a mail-in survey (n = 2,000). I also examined the influence of weather and row-crop harvest progress on daily harvest of white-tailed deer by archery hunting. Hunter efficiency ( ¡À SE= 0.12 ¡À 0.01 deer/day) and hunter success (range = 1.25-1.39 deer/hunter) were similar between study areas. No relationship (r2 <0.01) was detected between respondent age and hunter efficiency, but had a weak influence (r2 = 0.006) on hunter success. Respondents that preferred shotguns, used 1 weapon, and those that preferred still hunting had 62%, 58%, and 52%, respectively, greater (P ¡Ü 0.001) mean hunter efficiency than those in the lowest group within their particular categories. There was no apparent difference (P ¡Ý 0.087) in hunter efficiency across categories of area familiarity, number of hunting methods used, and scouting hours, or categories related to access and use of reconnaissance tools. Respondents that had ¡Ý11 years of area familiarity, preferred archery hunting, used ¡Ý 3 weapons, used ¡Ý3 hunting methods, scouted ¡Ý30 hours, and preferred tree stands had 51%, 45%, 62%, 35%, 61% and 41%, respectively, greater (P ¡Ü 0.001) mean hunter success than those in the lowest group within their particular categories. Access and use of GIS did not appear to affect (P = 0.376) hunter success. Respondents that had access and used topographic maps, aerial or satellite photographs, or GPS had 35%, 34%, and 29% greater (P ¡Ü 0.049), respectively, hunter success than those in the lowest group within their particular categories. Crop harvest progress did not (P = 0.780) appear to affect daily harvest of white-tailed deer by archery hunting. Three models of weather impacts on daily harvest of white-tailed deer by archery hunting had AICc <2. The most parsimonious models¡¯ covariates were MaxWSP, MSLP, and WDSP1, with MaxWSP (¦Â = -0.005) having a negative influence and MSLP (¦Â = 0.00007) and WDSP1 (¦Â = 0.006) having a positive influence on daily harvest of white-tailed deer by archery. I compared direct- and indirect distance sampling techniques for estimating white-tailed deer densities on study areas in east-central Illinois (ECI), southern Illinois (SI, 2007 only), and northern lower peninsula of Michigan (MI) during winter 2007-08. Density estimates obtained via indirect distance sampling for MI, ECI, and SI were 6.1-12.7, 11.2-15.8, and 15.4 deer/km2, respectively. Density estimates obtained via direct distance sampling for MI, ECI, and SI were 18.3-25.2, 14.4-18.1, and 19.0 deer/km2, respectively. Upon examining confidence interval (CI) overlap between direct- and indirect distance sampling techniques by year and study area, only the MI study had non-overlapping CI values. An examination of sites used by deer in summer and quantification of their survival and dispersal rates were conducted in east-central Illinois. From December 2005 to September 2009, I monitored 105 white-tailed deer for 35,478 radiodays for survival and dispersal analysis. I used Program MARK to estimate rates of annual survival, seasonal survival, and dispersal for fawns, yearlings, and adults. I measured habitat variables at sites used by white-tailed deer in summer and random locations in east-central Illinois, examining potential differences in site selection by sex and at multiple scales. Male and female full-season (winter/spring [16 Dec¨C14 May], summer [15 May-30 Sep], fall/winter [1 Oct¨C15 Dec]) survival rate ranged from 0.56 to 0.95 and 0.84 to 0.95, respectively. Male survival was lower than that of females during the fall/winter season for a model not accounting for overdispersion. Averaging across parsimonious models, the dispersal rate for yearling and fawn males and yearling and fawn females were 0.44 ¡À 0.07 and 0.41 ¡À 0.07, respectively. Adult male dispersal rate was 0.46 ¡À 0.15 and no adult females dispersed. Slight differences were observed in habitat variables at sites used by male and female white-tailed deer, but hypotheses of sexual segregation between the sexes were not supported. Males were never observed in developed landcover. Sex differences in the use of developed landcover approached significance with females using sites with that landcover 131% more than males; they also used sites with 87% higher patch density of wetland landcover than males. Based on the best-fit AIC model, overall (i.e., both males and females) site selection of white-tailed deer was influenced by patch density of agriculture landcover, percentage of fallow field landcover, disjunct core area of the landscape, upper visual obstruction, and percentage of shrubs. Increases in upper visual obstruction and percent of shrub increased the likelihood of a site being selected. Decreases in patch density of agriculture landcover, percentage of fallow field landcover, and disjunct core area of the landscape increased the likelihood of a site being selected. This study provides updated information regarding white-tailed deer demographics, habitat use, survey methods, and hunter behavior to white-tailed deer managers in the Midwest. The data produced from mail-in surveys may provide knowledge of influences on hunter efficiency and success that may be used to manipulate deer harvest under a declining number of hunters in the U.S. Consistent estimates of density between indirect- and direct distance sampling shows utility for use of direct distance sampling within agriculturally-dominated regions of the Midwest. Fine-scale management by private landowners may benefit from my data by demonstrating a preference for a particular landscape signature by deer during the summer.
78

Population Demographics and Space Use of White-tailed Deer in the Northern Lower Peninsula of Michigan

Stroud, Janice Kay 01 January 2009 (has links)
I studied population demographics and space-use of white-tailed deer in Manistee and Mason counties in the northern lower peninsula of Michigan during 2005-08. Deer density from spring spotlight distance sampling surveys was 20.1 ± 1.7 deer/km2. The sex ratio was 14 bucks:100 does and the age ratio was 84 fawns:100 does. I radiomarked and monitored 105 does (62 adults and 43 fawns) for survival and space use. Annual adult survival was 0.74 ± 0.06, with most mortalities (n = 8 of 23) caused by human harvest. Adult survival was the highest during winter (1.00) and lowest in autumn (0.81 ± 0.08). Winter/spring fawn survival was 0.74 ± 0.06, with all mortalities caused by predation (n = 4) and starvation (n = 3). Mean size of composite home-ranges and core-areas were 2.0 ± 0.1 km2 and 0.4 ± 0.02 km2, respectively, and did not differ seasonally. Cover-type use did not differ seasonally between home ranges and core areas, indicating that deer did not select specific cover types within their home range. Vegetated openland and mast-producing upland forests received the highest proportion of use in home ranges (47% and 23%, respectively) and core areas (49% and 21%, respectively). These data will be beneficial for modeling deer population growth and response to harvest and to focus habitat management prescriptions for the Little River Band of Ottawa Indians.
79

Testing New Measures of Age Independent Body Size in White-Tailed Deer (Odocoileus virginianus)

Densmore, Julie A. 08 1900 (has links)
The four elements of the lower hind foot (calcaneus, metatarsal, naviculo-cuboid, and tibia) were tested for use as age-independent proxies of body size in white-tailed deer using known aged specimens from Ft. Hood Texas. Statistical analysis indicates that the calcaneum and the tibia are good proxies of age-independent body size in white-tailed deer. In addition to expanding the list of elements that can be used for studies of age-independent body size, these elements can also be used to age faunal remains to an ordinal scale of juveniles and adults. This is useful for research regarding prehistoric prey populations; as a single element can be used to determine prey body size and age simultaneously, which are the two variables used to assess changes in human subsistence practices via the archaeological remains of their prey.
80

Seasonal variations in concentrations of circulating thyroid hormones and their relationships to diet in the white-tailed deer

Oelschlaeger, Anne January 1979 (has links)
Three experiments were conducted to determine the effect of energy, protein, sex, and time on serum T4 and T3 concentrations. All sampling periods occurred at 28-day intervals. In the first experiment, (March-February) 7 adult bucks were placed on 2 feed levels, ad libitum or 25% restricted. Feed consumption of ad libitum deer was highest (P≤0.05) from June-October, fell in November, and remained low through March. Body weights of both groups were highest (P≤0.05) from September-October; lowest from March-April. Serum T4 was highest (P≤0.05) in May and July, and lowest in November. From November-February, restricted deer had lower T4 concentrations (P<0.01) than did ad libitum deer. Serum T3 was highest from May-August; lowest in November. Ad libitum had higher T3 concentrations (P<0.01) than the restricted animals. The second experiment compared the effects of energy and protein on body weight, and serum T4 and T3 of 24 fawns (12 male) from October-May. Feed intake fell gradually to low levels maintained from January-March, then increased slightly. Body weight gain was initially rapid (P<0.01), minimal from November-March, and slow through May. Serum T4 was highest in late April; lowest in October and February. Maximum serum T3 concentrations occurred in April; lowest values in February. Females had higher T4 and T3 values than did males. The third experiment involved 1 adult buck. Blood samples were drawn every 2 hours for a 24-hour period via a jugular catheter. Serum T4 and T3 concentrations were highest from 1600-2000 hours (EST), lowest at 1000 hours. / M.S.

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