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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.
61

The Mass-Personal Divide: Bridging Scholarship and Paving Ground Through the Lens of Environmental Discourse on Public Land Use

Seroka, Laura A. 19 November 2019 (has links)
No description available.
62

Digestibility of Foods and Anthropogenic Feeding of Black Bears in Virginia

Gray, Rachel Masterson 29 August 2001 (has links)
For years, bear hunters have provided an unknown amount of food to black bears <i>(Ursus americanus)</i> in Virginia, supplementing their natural food supply. Possible effects of feeding bears can be negative, such as food conditioning and habituation to people, or positive, such as enhanced or sustained reproductive rates, especially in years of mast crop failure. In July 1999, the Virginia Department of Game and Inland Fisheries (VDGIF) adopted a regulation recommendation that prohibited the feeding of wildlife on national forest and department-owned lands. We mailed a survey to all members of the Virginia Bear Hunters Association (VBHA, n = 459) to determine the amount of food provided to bears by bear hunters in Virginia between 1 July 1998 and 30 June 1999. Survey response rate was 52%. One hundred thirteen of 238 (47.5%) survey respondents spent over $18,000 on supplemental food in one year, averaging $163/person. One hundred twenty-eight respondents reported cumulatively providing nearly 3 million kilograms of food to bears between 1 July 1998 and 30 June 1999. Whole-shelled corn, pastries, and grease accounted for 58% of the total food by weight; however, whole-shelled corn, pastries, and bread were the 3 most common foods offered. Feeding occurred in 25 counties in Virginia, primarily during July, August, and September. Rockingham County had the highest proportion of feeders (47%), followed by Giles (15%), Augusta (14%), Craig (9%) and Montgomery (9%) Counties. Accordingly, Rockingham County received the highest proportion of food (42%), followed by Craig (8%), Giles (7%), Montgomery (6%), and Tazewell (6%) Counties. The low survey response rate, coupled with the fact that 48% of sampled nonrespondents fed bears, suggests that the total amount of annual feeding in Virginia may exceed the total determined during this study. However, the possibility of an avidity bias, in which a higher response by the more avid feeders would erroneously inflate a total estimate extrapolated to include feeding by nonrespondents, cannot be eliminated. Little work has been done pertaining to digestibilities of black bear foods, particularly those in the eastern United States. We determined digestibilities for several important eastern black bear foods, including northern red oak <i>(Quercus rubra)</i>, white oak <i>(Q. alba)</i>, and chestnut oak acorns <i>(Q. prinus)</i>, squawroot <i>(Conopholis americana)</i>, high-protein dogfood, shelled corn, and doughnuts. All diets were evaluated for nutrient content as well as percent dry matter digestibility of crude protein, ether extract (a measure of fat), and gross energy. Diets we suspected were high in fiber were additionally evaluated for neutral detergent fiber or acid detergent fiber content and digestibility. Feeding trials were conducted with 1 male and 4 female captive bears during fall 1998, and 5 female captive bears during fall 1999, at the Center for Ursid Research, Blacksburg, Virginia. Acorns and squawroot were high in fiber (45-62%) and moderate to low in protein (5-7%). Fat content was high in doughnuts (24.7) and northern red oak acorns (12%), moderate in dogfood (8.2%) and white oak acorns (4.7%), and relatively low in shelled corn, chestnut oak acorns, and squawroot (1.3-3.5%). Crude protein was high in dogfood (29%) and moderate in all other diets (4.7-8.8%). Neutral detergent fiber content was high in squawroot and all acorn types (45-62.4%). Acid detergent fiber was high in squawroot (47%) and moderate in dogfood (9%). In 1998, crude protein digestibility was high in doughnuts (86%), moderate in shelled corn and white oak acorns (50-64%), and negligible in northern red oak acorns (-39%). Ether extract digestibility was high in doughnuts, red oak acorns, and white oak acorns (80-97%), and moderate in shelled corn (67%). Fiber digestibility was tested only on northern red oak and white oak acorns, and was moderate (62% and 68%, respectively). In 1999, crude protein digestibility was high in dogfood, dogfood mixed with squawroot, and doughnuts (75-85%); moderate in shelled corn, squawroot, and white oak acorns (43-58%); and low to negligible in chestnut oak and northern red oak acorns (-13-6%). Ether extract digestibility was moderate in shelled corn (64%) and squawroot (60%), and high in all other diets (79-97%). Neutral detergent fiber digestibility was moderately high in all acorn types (54-71%). Acid detergent fiber digestibility was moderate for dogfood (66%), and associative effects occurred between the fiber in squawroot and dogfood, resulting in negative fiber digestibility in squawroot determined by difference (-19%). A luxury not always realized in wildlife management is the ability to investigate possible effects of management or policy changes prior to their employment. The amount of food provided to bears by bear hunters in Virginia may have been more substantial than previously believed, and likely provided bears with a high energy, stable food source that supplemented their natural food supply. We did not have the opportunity to study the effects of removing that food source on public lands prior to the regulation change; however, the opportunistic feeding strategy of bears, coupled with sufficient mast production at the time of the regulation change, likely softened any negative effects that may have occurred as a result of the removal of supplemental food as a regular food source for some bears. / Master of Science
63

DNA-based hair sampling to identify road crossings and estimate population size of black bears in Great Dismal Swamp National Wildlife Refuge, Virginia

Wills, Johnny 17 October 2008 (has links)
The planned widening of U.S. Highway 17 along the east boundary of Great Dismal Swamp National Wildlife Refuge (GDSNWR) and a lack of knowledge about the refuge's bear population created the need to identify potential sites for wildlife crossings and estimate the size of the refuge's bear population. I collected black bear hair in order to collect DNA samples to estimate population size, density, and sex ratio, and determine road crossing locations for black bears (Ursus americanus) in GDSNWR in southeastern Virginia and northeastern North Carolina. I also investigated bear/vehicle collisions to determine patterns of road crossing. Genetic analysis of 344 hair samples collected on 2 trapping grids identified 85 unique individuals which I used in a mark-recapture analysis. Estimated population size on the trapping grids was 105 bears (95% CI = 91-148) and average density was 0.56 bears/km². This density estimate projected over the entire Great Dismal Swamp ecosystem yielded a population estimate of 308 bears (550 km2 X 0.56 bears/km²). Similar population estimates generated by Hellgren (1988), Tredick (2005), and this study suggest a stable bear population in the Great Dismal Swamp ecosystem over a 20-year period. I erected a 2.3-kilometer long strand of barbed wire along U. S. Highway 17 to monitor road crossing patterns near the Northwest River drainage. Genetic analysis identified 6 bears (4 males, 1 female, 1 unknown) that apparently crossed the highway in a 10-month period. Five of 6 bears deposited hair in a 171-m section which included the Northwest River corridor. The 6 bears detected crossed the road at least 11 times. I investigated 10 reports of bear/vehicle collisions on the periphery of the refuge from June 2000 to May 2002. Six bears (4M:1F:1 unknown) were confirmed killed during this time period. Based on reported bear/vehicle collisions from Hellgren (1988), the Virginia Department of Game and Inland Fisheries database, and this study, a minimum of 4 to 5 bears are struck by vehicles each year on the periphery of the refuge. I identified 2 areas of multiple bear/vehicle collisions: highway 58 on the north side of the refuge near Hampton Airport and Highway 17 on the eastern side of the refuge in the vicinity of the Northwest River corridor. / Master of Science
64

Den Tree Avaliability and Denning Success of Black Bears on Industrial Forest Lands and National Forest Lands in Virginia and West Virginia

Quince, Gyasi Adrian 09 July 2002 (has links)
During 1999-2001, potential den trees and denning success of black bears was investigated on industrial forest lands and national forest lands in Virginia and West Virginia. One hundred and fifty seven potential den trees were found on five study areas, 135 on national forest lands and 22 on the industrial forest lands. Twenty-seven hollow potential den trees were found, 22 on national forest lands and 5 on industrial forest lands. Densities of potential den trees ranged from 12.5/km2 to 437.5/km2 on the national forest lands and on the industrial forest lands the densities ranged from 0-187.5/km2. There were significantly higher densities (F1, 69=5.86, P=0.0181) of potential den trees on the national forest land than on the industrial forest land. There were also significantly (F=2, 68=7.86 P=0.0008) higher densities of hollow potential den trees based on the stand age class. Denning success for females expected to have cubs was 98% (n=46) in tree dens on national forest lands and 100% (n=8) on industrial forest lands. Denning success for females expected to have cubs was 76% (n=55) in ground dens on national forest lands and 80% (n=5) in ground dens on industrial forest lands. Females expected to have cubs on the national forest lands had an overall denning success of 89% (n=80) and on industrial forest lands there was overall, 92% (n=13) denning success. Chi-square tests showed that abandonment of dens by bears was significantly higher (x2=19.02, 1df) in ground dens than in tree dens. Litter sizes were not different from national forest lands and industrial forest lands (t=-0.36, 44df, P=0.84). The mean litter sizes on the national forest lands was 2.55 (SE=0.16) cubs per litter and on the industrial forest land 2.4 (SE=0.22) cubs per litter. / Master of Science
65

Population dynamics and denning ecology of black bears in Shenandoah National Park, Virginia

Carney, Daniel W. January 1985 (has links)
During 1982-85, population dynamics and denninq ecology of black bears (Ursus americanus) were investigated in Shenandoah National Park, Virginia. Foot snares and culvert traps were used to capture 115 bears a total of 149 times. Radio transmitter collars were fitted to 47 bears. The age structure of the bears captured was indicative of an exploited population. The minimum breeding age of females was 2 years, but 3 years was the modal age. Mean litter size determined by cub counts was 2.0 and females usually bred every second year. Annual mortality rates were estimated at 30% for cubs, 54% for yearlings, 39% for 2-year olds, and 21.5% for older bears. Radio collared adult males had an annual mortality rate of 41.5%, over 5-fold that of adult females (7.5%). Bear density was estimated at 1 bear/0.96-1.49 km'. This high density was explained in part by the difference in male and female mortality rates. The estimated rate of population increase indicated that the population was stable. The most common den types were rock cavities (29 of 61) and above-ground tree cavities (19 of 61). Males did not den in tree cavities. Den sites were not selected for forest type, aspect, or elevation, but ground slope was greater at den sites (P < 0.001) than at random points. Among- and within-year differences in dates of den entry, den emergence, and parturition were unrelated to weather and hard mast production. / Master of Science / incomplete_metadata
66

Seasonal movements, habitat selection, and food habits of black bears (Urus americanus) in Shenandoah National Park, Virginia

Garner, Nathan Paul January 1986 (has links)
The seasonal movements, food habits, and habitat selection of black bears (<i>Ursus americanus</i>) in Shenandoah National Park, Virginia were studied from May 1982 to April 1985. A total of 47 collared bears, including 25 adult females, 17 adult males, and 5 subadult males < 3.5 years old, was located 3973 times during the study. Adult males had larger (<i>P</i><0.001) home ranges (100% X=195 km², 95% X=116 km²) than adult females (100% X=38 km², 95% X=22 km²). Subadult males had larger (<i>P</i><0.10) home ranges (100% X=542 km², 95% X=289 km²) than adult males and females. Extensive home range overlap occurred among each sex and age group. At least three subadult males dispersed from the Park during the study. Female bears with cubs were less mobile than solitary females during the spring. Fall cubs were large and did not restrict females' movements. Large fall home ranges for females were related to the scattered supply of acorns relative to the concentrated sources of soft mast used in the summer. Two females with cubs and 2 subadult males remained active during the winter months. Adult and subadult males generally had less stable home ranges than adult females. Female bears displayed infidelity to given areas during the fall from year-to-year due to variation in the distribution of hard mast (acorns). Male bears made long excursions onto the Piedmont Plateau east of the Park mainly during the spring and early fall. Females were not exposed to as much human induced mortality as males because they were located within the Park 17% more frequently than males. Males avoided fire roads (<i>P</i><0.001), light duty roads (<i>P</i><0.001), and primary roads (<i>P</i><0.01) year around. Female bears preferred fire roads during summer (<i>P</i>< 0.001) and early fall (<i>P</i><0.01) and avoided heavier traveled roads such as light duty roads (<i>P</i><0.001) and primary roads (<i>P</i><0.001) year around. Both male and female bears preferred foot trails for travel (<i>P</i><0.05). Bears rarely came within 100 meters of campgrounds, picnic areas, and other human disturbance areas within the Park. Both sexes used low (<i>P</i><0.10) elevations during the summer and high (<i>P</i><0.10) elevations during early and late fall. Bears showed the greatest use of small rivers and streams during the driest months of summer. Geographic land forms of specific aspects, contours, and varying steepness were used differently by male and female bears. Twelve stomachs and 854 scats were analyzed for food content. Forbs, graminoids, squawroot (<i>Conopholis americana</i>), corn, and the fruits of trees, shrubs, and vines composed 90 percent volume of the annual diet. Eight percent of the food consumed was animal matter from mammals, birds, and invertebrates. During all seasons, females used yellow poplar (<i>Liriodendron tulipifera</i>) forests more (<i>P</i><0.05) than males while males used yellow poplar forests less (<i>P</i><0.05) than expected; males used black locust (<i>Robinia pseudoacacia</i>) \ black cherry (<i>Prunus serotina</i>) forests more (<i>P</i><0.05) than females and more (<i>P</i><0.05) than expected. Shifts in use of chestnut oak (<i>Quercus prinus</i>) \ northern red oak (<i>Q. rubra</i>) forests and northern red oak \ white oak (<i>Q. alba</i>) forests by both males and females in early and late fall was attributed to annual variation in oak mast production, preference for white oak acorns, foraging strategy, and the importance of mountain laurel (<i>Kalmia latifolia</i>) shrub cover in late fall. Seasonal use of domestic fruits at 330 abandoned homesites was determined. Distance-to-nearest-homesite measurements indicated that males were never closer (<i>P</i>>0.10) to homesites than females or random points during any season while females were closer (<i>P</i><0.001) to homesites than males and random points during summer. Only females were located at homesites (≤ 100m) more (<i>P</i><0.001) than expected during summer and early fall. Bears consumed apples (<i>Malus</i> spp.) and sweet cherries (<i>Prunus avium</i>) at abandoned homesites mainly in summer, early fall, and late fall. Bears used homesites in late fall more than distance measures indicated. Domestic fruits were an important nutritional food for black bears in relation to total soft fruits eaten. / Master of Science / incomplete_metadata
67

Deidamia Inscriptum (lettered Sphinx Moth) Caterpillars Feeding on Oxydendrum Arboreum (sourwood) and Their Predation by Black Bears in Northeast Tennessee

Levy, Foster, Wagner, David L., Walker, Elaine S. 01 September 2016 (has links)
An outbreak of Deidamia inscriptum (Lettered Sphinx Moth) caterpillars was noted in northeast Tennessee where Oxydendrum arboreum (Sourwood) trees were defoliated. Nearly all published literature and online resources list only plants in the grape family (Vitaceae) as larval food plants. Food-plant preference trials using fresh leaves of 3 woody plant species showed that Deidamiacaterpillars from this region had a preference for Sourwood over Parthenocissus quinquefolia(Virginia Creeper), and rejected Acer rubrum (Red Maple), a non-host species. Ursus americanus(Black Bear) were feeding on the caterpillars as evidenced by bent and broken Sourwood saplings bearing claw marks and by abundant sphingid remains in bear scat.
68

Black Bears (Ursus americanus) versus Brown Bears (U. arctos): Combining Morphometrics and Niche Modeling to Differentiate Species and Predict Distributions Through Time

Kantelis, Theron Michael 01 May 2017 (has links)
Late Pleistocene American black bears (Ursus americanus) often overlap in size with Pleistocene brown bears (U. arctos), occasionally making them difficult to diagnose. Large U. americanus have previously been distinguished from U. arctos by the length of the upper second molar (M2). However, the teeth of fossil U. americanus sometimes overlap size with U. arctos. As such, there is need for a more accurate tool to distinguish the two species. Here, 2D geometric morphometrics is applied to the occlusal surface of the M2 to further assess the utility of this tooth for distinguishing U. americanus and U. arctos specimens. When combined with an Ecological Niche Model of U. americanus and U. arctos in North America from the Last Glacial Maximum, this morphometric technique can be applied to key regions. A case of two Pleistocene specimens previously identified as U. arctos from eastern North America exemplifies the utility of this combination.
69

Ilgalaikių asmeninių investicijų strategijų ir valdymo metodų analizė / The analysis of long-term personal investment strategies and management methods

Stankevičiūtė, Agnė 24 February 2010 (has links)
Magistro baigiamajame darbe nagrinėjama investicijų planavimo, klasifikavimo, pasirinkimo galimybės, investicinio portfelio sudarymo metodai ir ilgalaikės strategijos teoriniu aspektu, bei išanalizuotos investicinių fondų strategijos trimis finansų rinkos laikotarpiais. Tyrimo objektas – investiciniai įrankiai, ilgalaikės investavimo strategijos. Tikslas – išanalizuoti ilgalaikes investavimo strategijas skirtingais ekonomikos tarpsniais ir išsiaiškinti kas lemia žemus investicinius rezultatus. Magistro baigiamojo darbo uždaviniai – atlikti investavimo ir asmeninių finansų planavimo literatūros analizę, išsiaiškinti investavimo priemones Lietuvoje bei įvertinti jų riziką, išanalizuoti ilgalaikio investavimo į investicinius fondus strategijas, remiantis gautais tyrimo rezultatais pateikti išvadas ir siūlymus investicinių fondų pasirinkimo ir valdymo srityje. Tyrimo metodika: mokslinės literatūros, straipsnių, statistinių duomenų lyginamoji analizė. Nustatytos tokios pagrindinės gairės investicijų pasirinkimui – investavimo tikslų išsikėlimas, naudojant asmens gyvenimo ciklo modelį, ilgo investavimo termino nusistatymas, potencialių ekonominių ir geografinių sektorių pasirinkimas, turto klasės pasirinkimas, investicinio portfelio formavimas. Tiriamojoje dalyje išanalizuotos investicinių fondų valdymo strategijos - vertės augimo: investicijos į išsivysčiusių šalių rinkas, investicijos į Europos vertės augimo rinkas, investicijos į besivystančių šalių rinkas , investicijos į... [toliau žr. visą tekstą] / In this master graduation work author examines the investment planning, classification, possibilities for the options, methods of the investment portfolio creation and long-term strategies in theoretical approach. Moreover, in this work author analyses investment funds and strategies in three different periods of the financial market. The object of the research – investment tools (instruments), long-term investment strategies. The main goal of this master graduation work is to analyze long-term investment strategies in different economical stages pursue to disclose the cause reason of the low levels in the investment results. The main tasks of this master graduation work is to accomplish analysis of the investment and individual financial planning, to identify investment measures in Lithuania and to assess their risks, to analyze the investment strategies to the long-term investment funds, on the grounds of the research to bring out the conclusions and suggestions in the selection area of investment fund choice and management. Research methodology: analysis of the scientific literature, articles, likewise statistical data comparative analysis. Author identifies the following guidelines for the choice of investment – the elevation of the investment purposes by using personal life cycle model, determination of a long-term investment period, a choice of potential economical and geographical sectors, a choice of the asset classes, and formation of the investment portfolio... [to full text]
70

Attitudes, trust, and wildlife co-management in Igluligaarjuk, Qamani’tuaq, and Tikirarjuaq, Nunavut, Canada

2015 January 1900 (has links)
Research has shown that trust is essential to the functioning of co-management. This is especially true in the Territory of Nunavut where wildlife is an integral part of the lifestyle and culture of Nunavummiut (the people inhabiting Nunavut). In Nunavut, wildlife is managed by a co-management board situated in between federal, territorial, regional, and community governments and organizations. This research explores Inuit attitudes and trust in managing wildlife as part of a co-management system in the Kivalliq Region of Nunavut, Canada. Interviews were conducted in the communities of Igluligaarjuk (Chesterfield Inlet), Tikirarjauq (Whale Cove), and Qamani’tuaq (Baker Lake). Even now with the 1993 settlement of the Nunavut Land Claims Agreement (NLCA) and the implementation of a public government in 1999, there is documented evidence that beneficiaries of the NLCA are dissatisfied with wildlife management decisions and do not trust the governing process of co-management. In this study, participants specifically indicated dissatisfaction with regulations and outcomes of current polar bear co-management. It has been predicted that conflicts specific to polar bear management could lead to regulations being ignored or even defied and endanger the entire system of wildlife co-management. Results from this research indicate that dissatisfaction over decisions involving polar bears is dominantly compartmentalized towards the outcomes of polar bear management and does not necessarily apply to the broader system of wildlife co-management. Therefore, in the Kivalliq Region, predicted impacts of dissatisfaction over polar bear co-management may apply directly to the polar bear co-management system but likely not the wildlife co-management system generally. This study provides a forum where Inuit trust in the wildlife co-management system is documented and I hope it will contribute to an increased understanding of Inuit goals in wildlife management and to the discourses on co-management in Nunavut.

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