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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.
151

Evaluating the Use of Fecal Transthyretin as a Biomarker for Noninvasive Pregnancy Diagnosis in the Polar Bear (Ursus maritimus)

DeLorenzo, Corrina J. January 2017 (has links)
No description available.
152

The Evolution of "Monsters" in North American Exploration and Travel Literature 1607-1930

Shoalts, Adam January 2019 (has links)
In the first two centuries of European exploration of North America, accounts of monsters, including ones given by Indigenous guides, were largely accepted by Europeans as reflecting actual creatures. Gradually, under the influence of a range of factors, this dynamic shifted over time. Continued exploration, the spread of Enlightenment ideas, and changing material circumstances led to a decline in the belief in monsters—or at least put the belief in them beyond respectability, thereby enlarging the cultural gulf between various Indigenous cultures and European explorers and settlers, or at least the social elite of that latter group. In Canada, as argued here, the “sasquatch” was a hybrid creation combining Indigenous and European traditions; the windigo was an Indigenous monster tradition; the “grisly bear” was predominately a monster of the European imagination. Perceptions of each in European exploration literature followed a similar trajectory of increasing skepticism. Each evolved from creatures that were depicted as innately hostile or dangerous into somewhat more benign pop culture images as they lost their potency once the frontier receded and North America urbanized. As the gap in perspectives on monsters widened in exploration and frontier literature over the course of the nineteenth century, new narratives emerged that were much more negative in their depictions of Indigenous peoples. Frequently, this negativity, when connected with monster legends, depicted Indigenous peoples as cowardly or superstitious. With the sasquatch, European stereotypes about Indigenous people had by the 1870s partially supplanted what had once been a sense of genuine mystery regarding this frontier legend. The exploitation of windigo stories to portray Indigenous peoples as cowardly and superstitious also arose mainly after the 1870s, as earlier generations of explorers and fur traders had exhibited more receptive attitudes. Meanwhile many voyageurs and lower status trappers retained beliefs on monsters closer to their Indigenous counterparts, and as a result were often lumped into the same category as sharing premodern, superstitious beliefs by their social elites. Finally, in the third example, the “grisly bear” became a bloodthirsty monster in the European settler imagination. It was the last mainstream European monster myth, before it too largely faded away in the face of skeptical inquiry. However, such skepticism, voiced normally from afar, frequently misunderstood and misconstrued the nature of these legends, and the truths they had contained. / Thesis / Doctor of Philosophy (PhD)
153

Population Ecology of Black Bears in the Alleghany Mountains of Virginia

Bridges, Andrew Scott 26 May 2005 (has links)
The Cooperative Alleghany Bear Study (CABS) was a 10-year study conducted on 2 areas and designed to investigate the ecology of a hunted population of American black bears (Ursus americanus) in the Alleghany Mountains of western Virginia. Over the course of our research, we handled 1,041 individual bears >18 months old and gathered reproductive data from females during 424 bear-winters. My analyses of 183 litters indicate that reproductive rates were high with relatively large litters (mean = 2.49 cubs / litter) and younger (3–4-year-old) females having smaller litters than older (> 5 years old) females. Overall cub sex ratios did not differ from 1M:1F; however, female cubs were over-represented in 4-cub litters. Most cubs were born in January (mean = January 17) and younger females had later parturition dates than older females. Bears on our study areas had relatively early ages at primiparity (mean = 3.8 years old) and few missed reproductive opportunities. Hard mast failure apparently resulted in periodic reproductive failures and subsequent reproductive synchrony, which I tracked using 5 indices. The amplitude of oscillations in reproductive synchrony dampened through time after each synchronizing event. The population contained substantially more females than males; however, males were more vulnerable to trapping than were females. Population size was determined using genetic and photographic capture-recapture estimators. Density estimates were relatively high and approached 1 bear / km2. Annual survival rates were high for cubs (0.87) and females (0.91). For males, annual survival rates were lower, particularly for 1–3-year-olds (0.57). Excluding hunting mortality, natural survival rates were high (0.98) for all >1-year-old bears on our study areas. The results of Leslie Matrix and Program RISKMAN models indicated a growing population. A Leslie Matrix model incorporating the effects of a 5-year-cyle of mast-failure-induced reproductive failure yielded a lambda = 1.13. To reach the objective of 0 population growth prescribed for some areas of Virginia, increased levels of hunting mortality on adult (>3-year-old) females would likely be necessary. / Ph. D.
154

Population dynamics of Virginia's hunted black bear (Ursus americanus) population

Klenzendorf, Sybille A. 26 April 2002 (has links)
The Cooperative Alleghany Bear Study (CABS) was initiated in 1994 by the Virginia Department of Game and Inland Fisheries (VDGIF) and the Virginia Polytechnic Institute and State University (VPI&SU) to investigate population dynamics on Virginia's hunted bear population. CABS personnel handled 746 different bears (1.5M:1F) 1,368 times on its northern study area during June 1994 to September 2000. The sex ratio for summer captures was 1.5M:1F, which differed from 1:1 (n = 1,008, Z = 6.17, P < 0.0001). Sex ratios for the summer captures ranged considerably among years (÷2 = 23.92, df = 6, P = 0.0005) and among age classes (÷2 = 119.22, df = 4, P < 0.0001), with the largest discrepancy among yearlings (5.7M:1F). The sex ratio among captured adults favored females (0.6M:1.0F ). Average age for all captured bears was 3.87 ± S.E. 0.12 years; females (n = 309) averaged 5.20 ± S.E. 0.16 and males (n = 402) averaged 2.84 ± S.E. 0.14 years (t = 10.92, df = 709, P < 0.001). Litter size averaged 2.35 cubs / litter over the 6-year period and sex ratio did not differ from 1:1 (n = 183, Z = 0.74, P = 0.461), but varied among years (÷2 = 16.61, df = 5; P = 0.005). Three-hundred-and-seventy-six (164M, 212F) of 746 captured individuals were equipped with radio-transmitters. The ratio of radio-collared bears fluctuated from 2.6 F:1M (1998) to 8.6F:1M. We tested a radio-collar effect on survival as a covariate and found a significantly higher survival for radio-collared adult and 3-year-old females in the first 3 years of the study (c2 = 6.64, 1 df, P = 0.01). Estimates using the Kaplan-Meier staggered entry showed survival rates for females (adults = 0.993, subadults = 0.997) higher than for males (adults = 0.972, subadults = 0.917). Estimates using the mark-dead recoveries data showed survival rates of 0.840 for adult females (0.714 for 2-year-olds) and 0.769 for adult males (0.335 for 2-year-olds). We observed 34 mortalities of radio-collared bears for which hunting mortality accounted for 85%. Four natural mortalities included a 5-year-old female and a 2-year-old male that were killed by other bears, and a 14-year-old and 2-year-old female that died of unknown causes. Among the ear-tagged sample, 2-year-old males experienced the highest mean harvest rate of 45%, with a high of 65% mortality in 1996. Among females, 2-year-olds were most vulnerable with a harvest mortality rate of 22% a year. Population modeling indicated that population growth rate of black bears in Virginia is most sensitive to changes in adult female reproduction and survival. With current survival and reproductive estimates, simulation indicated that adult female harvest has to increase 44% from current levels to stabilize population growth. Population size estimates using Bowden's estimate for mark-resight data for a 100 km2 sub-area on the northern study area ranged from 83-131 animals during 1998-2000. When adjusted for the proportion of time radio-collared bears spent on the study area population estimates fell to 63-96 bears. Using the Lincoln-Petersen estimate with Chapman's modification, black bear population estimates for the northern study area ranged from 582-1,026 animals during 1994-1999 on the 860 km2 area. Visitation rates to bait station sites correlated well with changes in population size estimates (n = 5, r = 0.97, P = 0.007). Black bear harvest in general was weakly correlated to change in population size (n = 6, r = 0.49, P = 0.328), however, archery harvest was highly correlated (n = 6, r = 0.95, P = 0.002). The monitoring indices showed all showed the same trends. We recommend a combination of them rather than relying on only a single index for monitoring Virginia's black bear population. During winters 1995–2001, located 215 dens of radio-collared bears; 68% were in trees. Ground dens used by bears included nests in laurel thickets, excavations, brush piles, and rock cavities. The proportion of bears using tree dens did not differ between our 2 study areas (n = 203, ÷ 2 = 1.63, 1 df, P = 0.202), the proportion of females using tree dens (65%, n = 127) was greater than that of males (33%, n= 15; ÷ 2 = 10.69, 1 df, P < 0.001) on the northern study area. Sex and age were significant factors in determining the type of den a bear selected. Twenty-six of 66 individual bears handled for 2–6 consecutive years consistently used tree dens, 8 were faithful to rock cavities, and only 4 regularly used ground dens for denning. Twenty-eight bears (42.4%) switched den types over the 6–year period, primarily from tree dens to rock cavities. / Ph. D.
155

Survival, family breakups, and dispersal of yearling and subadult black bears in western Virginia

Lee, Daniel James 03 March 2003 (has links)
Reported survival rates, dates of family breakup, and dispersal patterns for yearling and subadult bears in hunted black bear (Ursus americanus) populations in North America are scarce. We estimated survival rates of yearling and subadult black bears from a hunted population in western Virginia during 1999 - 2002. We captured and marked 307 different individual yearling and subadult bears on 2 study sites, and attached ear tag transmitters or radio collars to 54 (34M : 20F) 1-year-old, 52 (23M : 29F) 2-year-old, and 35 (8M : 27F) 3-year-old black bears. We used the known fate model in program MARK to estimate annual, non-hunting, and hunting season survival for radio-marked bears of each age and sex class. Additionally, we used mark-recapture data in the recaptures only, dead recoveries, and Burnham's combined models within program MARK to estimate annual survival for each age and sex class. One-, 2-, and 3-year-old female survivorship was 0.87 (95% C.I. 0.78 - 0.92), while 1-year male survivorship was 0.32 (95% C.I. 0.20 - 0.47), and 2- and 3-year-old male survivorship was 0.59 (95% C.I. 0.47 - 0.71) from the Burnham's combined model. Survival rates for 1-year-old females (χ2 = 6.20, P = 0.01) and 2-year-old females (χ2 = 7.74, P = 0.01) were higher than males in each age category, respectively. However, we detected no difference between 3-year-old females and 3-year-old males (χ2 = 2.61, P=0.11), likely due to small sample size of males (n = 4). Low yearling and subadult survival is not likely a cause for alarm due to the importance of adult female survival to population growth and the promiscuous mating system in black bear populations. Family breakup is an important event in the life history of black bears, marking the initial dispersal and home range construction of yearling bears, and perhaps marking the timing of estrus and breeding opportunities for adult females. We monitored 6 black bear family groups with 12 yearlings (6M : 6F) to determine the timing of family breakup; we intensely monitored 3 of the family groups to document home range establishment and movements by 5 subadult bears (2M : 3F) following separation from their mothers. Estimated dates of family breakup were 28 May and 2 June. Family breakups occurred before peak dates of estrus on our 2 western Virginia study areas. We detected 2 reassociations between a mother and her yearling offspring. Following family breakup, female yearlings (n = 3) remained within or partially on their mothers' home range while subadult males (n = 2) left their mothers' home ranges. All yearlings (n = 5) shared ≥50% of post-breakup home range with their mothers. We studied the movements of 31 (11M : 20F) subadult black bears born on our 2 study areas in western Virginia and 70 (44M : 26F) subadult bears captured during the summer on the study areas for dispersal. No radio-marked, resident, subadult female bears exhibited dispersal behavior while 3 of 11 (27%) radio-marked, resident, subadult males dispersed (P = 0.04). Resident and summer capture male bears moved greater distances than females from yearling den location (χ2 = 8.54, P = 0.01, df = 2) or summer capture location (χ2 = 22.02, P < 0.01, df = 2); no female moved > 10 km between initial and final locations (x = 2.7 km, range 0.2 - 9.0 km). The greatest subadult male movement was 80 km (x = 13.4 km, range 0.6 -0.80 km), and dispersal movements primarily occurred within the 1 and 2-year-old age classes. Direction of movement between initial and final locations for dispersing bears was not random (Rayleigh's r = 0.56, P = 0.02); bears appeared to follow the orientation of the predominant ridgelines and avoided leaving the national forest. / Master of Science
156

Vision Imagery and Its Relationship to Structure in the Novels of Flannery O'Connor

Sanders, Diane 08 1900 (has links)
An investigation of the prominence of vision imagery in the two novels of Flannery O'Connor, Wise Blood and The Violent Bear It Away, reveals the importance of vision to the themes and structures of the novels. Seeing truth in order to fulfill one's human vocation is a central concern in O'Connor's fiction. The realization or non-realization of truth by the characters is conveyed by vision imagery. O'Connor's Southern and Catholic heritage is the back-ground of her concern for vision as an integral part of her artistic theory. An analysis of vision imagery in each novel shows how the themes are developed and how the structures relate to such imagery. Each novel progresses according to the main character's clarity of sight. Contradictory patterns occur when the character's sight is not true.
157

Foraging ecology of brown bears in the Mackenzie Delta region, NWT

Barker, Oliver Unknown Date
No description available.
158

Foraging ecology of brown bears in the Mackenzie Delta region, NWT

Barker, Oliver 06 1900 (has links)
The Mackenzie Delta region, NWT, has a short growing season and highly seasonal climate, and brown bears (Ursus arctos) there face many challenges obtaining their nutritional requirements. Consumption of meat by brown bears is linked to increases in population density, fecundity, growth and body size. I examined the use of Arctic ground squirrels (Urocitellus parryii), and broad whitefish (Coregonus nasus) as meat sources by Mackenzie Delta brown bears. As a preliminary step, I built an Arctic ground squirrel habitat model, using field-surveyed ground squirrel burrow locations. Using this model, I examined bears selection for Arctic ground squirrel habitat as a population, by sex and as individuals, and linked this to results of stable isotope analysis and site investigations. Bears showed little evidence of Arctic ground squirrel use at the population and sex level, but some individual bears appeared to prey heavily on ground squirrels, particularly during hyperphagia. I also described observations of a brown bear using broad whitefish in autumn, and used telemetry locations to show that other bears may also feed heavily on broad whitefish during hyperphagia. My research provides prey-specific evidence for intrapopulation niche variation among Mackenzie Delta brown bears. / Ecology
159

Evaluation of an environmental education program for the Andean bear in an Ecuadorian protected area

Espinosa Andrade, Santiago. January 2004 (has links) (PDF)
Thesis (M.S.)--University of Florida, 2004. / Title from PDF title page (viewed on July 6, 2005). Includes vita. Includes bibliographical references (p. 110-116).
160

The Effects of Chronically Elevated N and S Deposition on the Nutrition and Physiology of Sugar Maple at the Bear Brook Watershed in Maine

Bethers, Suzanne January 2008 (has links) (PDF)
No description available.

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