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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.
91

Influence of limited access roads on Roosevelt elk in the Oregon Coast Range

Cole, Eric K. 07 March 1996 (has links)
No studies have evaluated the effects of limited vehicle access on movements, survival and habitat use of Roosevelt elk (Cervus elaphus roosevelti) . We installed twenty gates, restricting motorized vehicle access by the public in seven discrete Road Management Areas (RMAs), comprising 35% of the study area. We radio-tracked 31 cow elk for 13 months in a 38,000 ha area of the Oregon Coast Range. Prior to the installation of the gates, 20 of these elk had been tracked for 14 months, allowing a paired comparison of elk movements and habitat use before and during the limited access period. The percentage of elk home ranges or core areas within the RMAs did not differ between periods, but there was a clear decrease in daily movement of elk during the limited access period. Survival rates increased during the limited access period and declined after the removal of the gates. During the limited access period, there was a significant increase in the use of open, foraging habitats and areas <150 m from roads. We conducted habitat selection analysis on vegetative cover types, distance from roads and distance from water. In general elk use of vegetative cover types was not significantly different from availability (p<0.05). Elk avoided areas <150 m from roads and selected areas >150 m from roads. Elk selected areas <150 m from streams and avoided areas >600 m from streams. Roosevelt elk should benefit from the preferred alternative of the President's forest Plan, which maintains roadless areas near streams. / Graduation date: 1996
92

The effects of forage improvement practices on Roosevelt elk in the Oregon Coast Range

Stussy, Rosemary J. 06 December 1993 (has links)
Forage availability, diets, distribution, and productivity were compared for Roosevelt elk, Cervus elaphus roosevelti, using improved (i.e. seeded, fertilized, and grazed) and untreated areas of the Oregon Coast Range. Seasonal forage availability was substantially different on 1-year-old improved and untreated clearcuts, but the differences diminished by clearcut age 4 and essentially disappeared by clearcut age 7. Elk diets, as evaluated by fecal analysis, were similar in plant species composition and DAPA concentrations on both areas. There was no significant difference in estimated calf birth weights or survival, or in pregnancy and lactation rates, kidney and metatarsal marrow fat concentrations, or breeding dates of adult cows using improved and untreated areas. Summer and winter calf ratios were similar in 7 of 8 seasons sampled. There was no significant difference in home range or core area size, and distances traveled were similar on both areas in all seasons except winter. Elk exposed to summer sheep grazing were displaced an average of 1211 m (SD = 28 m) for an average of 14 weeks (SD = 5 weeks). Elk using improved areas stayed closer to forage areas in spring, but otherwise there was no significant difference in proximity to forage. Elk from both areas demonstrated preferential use of meadows, and used other forage areas in proportion to their availability. The combined results indicated that the forage improvement practices were ineffective in producing any measurable benefits for elk. / Graduation date: 1994
93

PREDICTION MODELS FOR DEER AND ELK FORAGE PRODUCTION IN ARIZONA MIXED CONIFER FORESTS

Thill, Ronald E. January 1981 (has links)
The objective of this study was to develop empirical regression equations for describing forest overstory-understory relationships in Arizona mixed conifer forests, and for predicting responses of potential mule deer (Odocoileus hemionus crooki) and elk (Cervus canadensis nelsoni) forage resources following thinning and clearcutting. Data were collected in the White Mountains from unlogged stands, a 2-year-old thinned stand, a 4-year-old thinned stand, an 8-year-old clearcut, and a 16-year-old clearcut. A combination of high variability in understory production (due presumably to inherent structurally-complex overstory conditions) and substantial intercorrelation between independent variables yielded multiple regression equations of questionable value. However, average understory production levels can be predicted using stand basal area alone. Relationships between basal area and understory production components were generally best described using log or log-log functions. Despite considerable diversity in slope and aspect conditions, potential insolation was generally not correlated with understory production; nor was potential insolation per unit of basal area often a better predictor than basal area alone. On unlogged sites production of potential deer forage was positively correlated with presence of spruce and fir, but negatively correlated with combined pine and Douglas-fir composition, and not significantly correlated with aspen composition. Potential elk forage was positively correlated with spruce and combined pine and Douglas-fir composition, but inversely correlated with aspen and fir composition. Understory production was generally inversely related to periodic annual forest growth and thickness of the forest floor. Browse production was generally less related to overstory conditions than herbage components, but was correlated with slope gradient and soil rockiness. Although total browse production could be estimated from basal area data, production of browse potentially useful to deer and elk could not be. Total understory production under virgin mixed conifer stands ranged from about 150 pounds per acre at 50 square feet of basal area (BA) to about 40 pounds at BA 400. The portion of this biomass potentially valuable as deer forage declined from 30% at BA 50 to 8% at BA 400, while elk forage declined from 49 to 11%. Forbs were the dominant understory component for all stand densities higher than about BA75, but were out-produced by graminoids below this level. Browse was the least productive understory component and increased only slightly with decreasing stand density. Total understory production on the 4-year-old thinned site was higher, but not statistically different than on unlogged sites; however, from 65 to 74% of the biomass consisted of forage potentially valuable to deer and elk. Depending on stand density, understory production under the 2-year-old thinning was comparable to or less than that of unlogged sites. Overstory-understory regression curves were often statistically different between thinned and unlogged stands. Diversity of principal deer and elk forage species increased as stand density declined under both unlogged and thinned stands. Unlogged stands produced slightly more potential elk than deer forage at lower stand densities, but production of deer and elk forage after thinning was nearly identical over the entire range of stand densities sampled on both thinned sites. The 8- and 16-year-old clearcuts produced about 750 and 1160 pounds per acre of biomass, respectively, with about 34% consisting of potential deer and elk forage on the younger site, versus 56% in the older clearcut. The 8-year-old clearcut produced 30% more elk than deer forage, and the 16-year-old site 7% more. The duration of beneficial deer and elk forage responses following clearcutting appears substantially longer than 16 years where tree regeneration is unsuccessful.
94

HABITAT USE BY ELK, MULE DEER, AND CATTLE IN ARIZONA.

Wallace, Mark Christopher, 1954- January 1984 (has links)
No description available.
95

Impacts of a Mixed Ungulate Community on Aspen Forests: From Landscape to Leaf

Rhodes, Aaron C. 01 November 2017 (has links)
This dissertation explores the differential effects of an ungulate community (cattle, mule deer, and American elk) on aspen (Populus tremuloides) regeneration pre- and post-fire disturbance. It's first chapter examines the differential effects of cattle, mule deer, and American elk on aspen regeneration across variable topography, climate and forest type; aspen dominant to conifer dominant subalpine forests. We found that each ungulate species, if sufficiently numerous, can cause aspen regeneration failure. Also, high elevation, southern aspect and high winter snow pack increase resilience to ungulate herbivory. Chapter two compares the efficacy of four methods of estimating ungulate impact on aspen. We found that direct methods of estimation (meristem removal, and defoliation) are better indicators of ungulate impact than indirect methods (fecal and camera counts). Therefore, we suggest to management that removal of apical meristems be an indicator for relative ungulate use. In chapters 3 and 4 we use differential ungulate exclosure fencing similar and camera traps to model the year to year and monthly use of aspen by ungulates. We model the per unit animal impact on aspen using photo counts. Our results show that ungulates on a per animal basis utilize aspen similarly. However, when adjusted for body size, native ungulates select aspen more often than cattle. Also, we found that while aspen is more palatable in June it is relative use, as measured by removal of apical meristems is significantly higher throughout July and August. We conclude that aspen is relatively more palatable than grass and forb species late season, and becomes and important forage species late season when forbs and grass species nutrient content drops. In chapter five, we quantify the physiological effects of ungulates on aspen regeneration after fire in order to elucidate the physiological mechanisms underlying plant:animal interactions. We show that ungulate herbivory induces high concentrations of defense chemistry (Phenolics), and reduces palatability through lower foliar nonstructural carbohydrates, and that this high investment in defense and lower growth potential related to low palatability causes severe reductions in aspen vertical growth leading to aspen regeneration failure. Together, we examine how biotic and abiotic factors at the landscape level, as well as defense and physiological function at the leaf chemistry level mediate how ungulates influence aspen regeneration and recruitment
96

Diet Composition and Activities of Elk on Different Habitat Segments in the Lodgepole Pine Type , Uinta Mountains, Utah

Collins, William B. 01 May 1977 (has links)
The biweekly diets of tame elk (Cervus canadensis nelsoni) were established on a species dry-weight basis for different habitat segments of the lodgepole pine (Pinus contorta) type, Principal species in the diets (5% or more) on each habitat segment were generally composed of preferred species. However, some highly abundant but non-preferred species took on principal dietary status, whereas some preferred species, scarce in the vegetation, contributed less than 5 percent to diets. Forbs contributed most to total consumption; grasses and sedges were the second largest contributors. Browse appeared to be of limited importance, but mushrooms had special significance in forested habitat segments. Preference changes were evident as forb species matured. Consumption rates were significantly higher in habitat segments having greater species diversity and forage density. The time tame elk spent grazing, ruminating, lying, grooming, traveling, standing, drinking, and playing was referenced to specific habitat segments in which each activity occurred. One thousand and eight hours of individual elk activity were observed over a series of six 24-hour periods. Wet meadows, dry meadows, clearcuts. and revegetated roads were preferred as grazing sites, while mature and stagnated forests were clearly non-preferred. Wet meadows, revegetated roads, and mature forest were preferred for resting and non-grazing activities. The distribution of pellet groups deposited by tame elk was determined with reference to habitat segment and form of activity at the time of deposition. Pellet group distributions thus obtained, were strongly unrepresentative of relative time spent in various habitat segments.
97

Reproduction and Hematology of the Cache Elk Herd

Follis, Thomas B. 01 May 1972 (has links)
The initial three years of a 10-year reproductive study of elk involved three major phases. A fourth was added because of convenience. Objective 1 was to ascertain pregnancy rates in yearling and mature elk by rectal palpation, associate these rates with subsequent fall cow/calf ratios, and to test concurrently an ultrasonic fetal heart detector. Rectally observed anatomical changes in gravid uteri of cattle were directly applicable to elk. Ultrasonic detections of pregnancies in elk and deer were unsuccessful. Pregnancy rates in the 1969-70 winter of 100 and 0 percent, respectively, for 19 adult and five yearling elk were associated with subsequent pre- and post-season cow/calf ratios of 100/55 and 100/68. Pregnancy rates the next winter of 82 and 17 percent, respectively, for 60 adults and 23 yearlings resulted in pre- and post-season cow/calf ratios of 100/52 and 100/39. Pregnancy rates in the 1971-72 winter were 82 and eight percent, respectively, for 39 adults and 13 yearlings; compilation of data for the first three years of the study precluded inclusion of associated fall and winter cow/calf ratios. Objective 2 was to determine the breeding efficiency of yearling male elk. Pregnancy rates were 86 and 93 percent, respectively, in 14 yearling-bred cows and 15 adult-bred cows in 1971. Rectal palpations revealed eight of 12 conceived in October from yearling breeding and 10 of 14 in September from adult breeding. A peak in yearling breeding was estimated to have occurred between October 11 and October 25, as compared to two peaks in adult breeding estimated near September 5 and September 20, The earliest and latest conceptions were estimated near October 5 and November 21, and September 5 and November 3, respectively, in yearling and adult bred cows. Most wild and captive yearlings polished or began peeling their antlers about October 1. compared to August 15 for captive adults. Data suggested recrudescent testicular tissues had initiated a rise in blood androgen, which coincided with a peak in breeding activity in September and October. lnducement of twin births in Objective 3 was attempted via synchronized superovulations during the September rut in 1970. Progestogen implants were used from 14 to 20 days to synchronize elk in two pre-rut trials and one mid-rut trial. Follicle-stimulating hormone (FSH) suspended in carboxy-methyl-cellulose (CMC), injected (intramuscular) coincident with implant removal was judged superior to pregnant mares serum (PMS) alone or FSH in peanut oil. Injections of FSH in anestrous elk produced a mean of 2.4 follicles and corpora lutea (CL) (2.0 follicles and 1.33 CL), the first week, and PMS produced a mean of 9.67 follicles and CL (8.67 follicles and 1.5 CL) response was low in a pre-rut trial with two levels of FSH in peanut oil. No conceptions apparently occurred in two groups of six cows injected with 15 and 20 milligrams FSH. Nine of 12 adults (including three of four controls) and none of four remaining yearlings were estimated to have conceived between September 30 and October 15 (five to 20 days after the treatment period), Two additional yearlings were superovulated with FSH without synchronization, but did not conceive. Data presented from blood analyses in Objective 4 included mean values for free-ranging mature elk (probability value indicates a significant difference between free-ranging and captive mature elk). The values were: total leucocytes (WBC), 6160/cubic millimeter (cu mm); WBC differential (percent)--neutrophils (44), lymphocytes (48, P < .05), monocytes (1), eosinophils (7), and basophils (0.1, P< .01); erythrocytes, 11 million/cu mm; hemoglobin, 21 grams/100 milliliters (g%), (P< .01); packed cell volume, 53 percent; blood urea nitrogen, 36 Sigma units (P< .01); serum glutamic-oxalacetic transaminase, 91 Units; lactic dehydrogenase, 863 Units; alkaline phosphatase, 2.22 Sigma units (P < .01); total protein, 7.0 g% (P < .01); albumin, 3.8 g% (P < .05); globulin fractions (g%)--alpha1 (A4), alpha2 (.6) beta (.95), and gamma (1.98); glucose, 183 milligrams/100 milliliters (mg%), (P < .05); creatinine, 2.9 mg%; uric acid, 0.39 mg%; cholesterol, 80.5 mg%; total bilirubin, 0.65 mg%; inorganic phosphorous, 3.4 mg%; and calcium ion, 9.2 mg%. Serology for Brucella abortus and Leptos pira pomona was negative. Blood values from five big game species and three species of domestic animals are presented for comparison. Significant differences in sampled elk were noted (P < .01 or < .05) in various tests between sexes, reproductive status, free-ranging and captive at different ages, and serial four-hour samples. A significant difference (P < .10) was noted in progestogen assays for non-pregnant and pregnant elk. Captive elk were positive and free-ranging were negative for Dictyocaulus infestations, Yearling and adult male reproductive tracts were microscopically differentiated. Nutritional conditions of experimental elk were considered excellent when fed a special pelleted formula freechoice with grass hay.
98

Reducing Reliance on Supplemental Winter Feeding in Elk (Cervus canadensis): An Applied Management Experiment at Deseret Land and Livestock Ranch, Utah

Mangus, Dax L 01 August 2011 (has links)
Wildlife managers have fed elk in North America for nearly 100 years. Giving winter feed to elk can compensate for a shortage of natural winter range and may boost elk populations while also helping prevent commingling with livestock and depredation of winter feed intended for livestock. In contrast to these benefits of supplemental feeding, there are economic and environmental costs associated with feeding, and elk herds that winter on feeding grounds have a higher risk of contracting and transmitting disease. Brucellosis is of primary concern now, and Chronic Wasting Disease may be in the future. Many see the discontinuation of winter-feeding programs as a necessary step for decreasing the risk of disease spread due to high animal densities associated with feeding during winter. My research evaluated the use of behavioral training to reduce reliance on supplemental winter feeding of elk, while minimizing population reductions and human-wildlife conflicts. My study was conducted at Deseret Land & Livestock (DLL) in Rich County, UT, where managers at DLL have over 20 years of data on elk feeding during winters of varying intensities. I tested the effectiveness of range improvements, strategic cattle grazing, dispersed supplemental feeding, hunting, and herding to distribute and hold elk in desired areas during winter. I compared elk numbers on the feed ground during this study with historic data on DLL, and also contrasted elk responses with other comparable feed sites in Wyoming that served as controls. In 2 mild winters we completely eliminated elk feeding without incident and were able to reduce the quantity and duration of feeding during 1 severe winter. Since the conclusion of my study, DLL has further reduced quantity and duration of feeding during severe winters, and has completely eliminated feeding in light winters. Based on a Before After Control Impact (BACI) analysis, the reduction in the proportion of the elk population fed at the study site was significantly less than the proportion of the elk populations fed at the control sites in Wyoming (P = 0.057). Based on these results, I anticipate wildlife managers can decrease dependence on costly supplemental winter feeding and reduce the risks of disease while keeping human-wildlife conflicts at a minimum. This research illustrates an adaptive method that can enable wildlife managers to keep elk populations in northern Utah at or near their current size, while constraining disease outbreak and transmission risks within "acceptable" levels.
99

Density and Feeding Habits of Elk and Deer in Relation to Livestock Disturbance

Clegg, Kenneth 01 May 1994 (has links)
Elk (Cervus elaphus) and mule deer (Odocoileus hemionus) density and foraging behavior were monitored in conjunction with disturbance by livestock (cattle and sheep) from 1991 to 1993 at Deseret Land and Livestock property near Woodruff, Utah. Elk and deer densities declined by as much as 92% in response to introduction of livestock, while associated areas where livestock were absent did not show this response. Biting rates and bite sizes were estimated and used to determine instantaneous intake rate. These measures were similar between pastures with cattle present or absent in 1992 but differed in 1993 for bite rate and marginally so for instantaneous intake rate. Bite rate and bite size but not instantaneous intake rate showed significant differences among years when the data for both treatments were combined. My results indicated that livestock locally displaced wild ungulates but displacement occurred only while the livestock were present. Differences in elk foraging behavior were greater between years than between treatments, and instantaneous intake rate alone was viewed as an inaccurate indicator of potential reductions in fitness.
100

Role of Protein Kinase C-iota in Neuroblastoma and the Effect of ICA-1, a Novel Protein Kinase C-iota Inhibitor on the Proliferation and Apoptosis of Neuroblastoma Cells

Pillai, Prajit P 01 January 2011 (has links)
Protein Kinase C-iota (PKC-é), an atypical protein kinase C isoform manifests its potential as an oncogene by targeting various aspects of cancer cells such as growth, invasion and survival. PKC-é confers resistance to drug-induced apoptosis in cancer cells. The acquisition of drug resistance is a major obstacle to good prognosis in neuroblastoma. The focus of the dissertation was three-fold: First to study the role of PKC-é in the proliferation of neuroblastoma. Secondly, to identify the efficacy of [4-(5-amino-4-carbamoylimidazol-1-yl)-2,3-dihydroxycyclopentyl] methyl dihydrogen phosphate (ICA-1) as a novel PKC-é inhibitor in neuroblastoma cell proliferation and apoptosis. Finally, to analyze whether PKC-é could self-regulate its expression. Cyclin dependent kinase 7 (Cdk7) phosphorylates cyclin dependent kinases (cdks) and promotes cell proliferation. Our data shows that PKC-é is an in-vitro Cdk7 kinase and that neuroblastoma cells proliferate via a PKC-é/Cdk7/cdk2 cell signaling pathway. ICA-1 specifically inhibits the activity of PKC-é but not that of PKC-zeta (PKC-æ), the closely related atypical PKC family member. The IC50 for the kinase activity assay was approximately 0.1µM which is 1000 times less than that of aurothiomalate, a known PKC-é inhibitor. The phosphorylation of Cdk7 by PKC-é was potently inhibited by ICA-1. ICA-1 mediates its antiproliferative effects on neuroblastoma cells by inhibiting the PKC-é/Cdk7/cdk2 signaling pathway. ICA-1 (0.1µM) inhibited the in-vitro proliferation of BE(2)-C neuroblastoma cells by 58% (P=0.01). Additionally, ICA-1 also induced apoptosis in neuroblastoma cells. Interestingly, ICA-1 did not affect the proliferation of normal neuronal cells suggesting its potential as chemotherapeutic with low toxicity. Hence, our results emphasize the potential of ICA-1 as a novel PKC-é inhibitor and chemotherapeutic agent for neuroblastoma. Bcr-Abl has been shown to regulate the activation of the transcription factor ELK-1 which in turn regulates the expression of PKC-é. Alternatively, we hypothesize that PKC-é can self regulate its expression by indirectly regulating the activity of Elk-1 in an ERK1 dependent manner. Our preliminary data shows that there was robust increase in the expression as well as association of PKC-é and Elk-1 in actively proliferating neuroblastoma cells suggesting a potential role of PKC-é in regulating the activity of Elk-1. Analysis of the subcellular fractions also presented a similar increase in the association between PKC-é and Elk-1 in the nuclear fraction of actively proliferating cells as compared to cytoplasm. Interestingly, the nuclear expression of PKC-é was also found to be higher in these cells, suggesting that PKC-é translocated to the nucleus in actively proliferating cells and regulated the transcriptional activity of Elk-1. However, our data from in-vitro kinase activity demonstrated that PKC-é was not an Elk-1 kinase but that it increased the phosphorylation of Elk-1 in the presence of ERK1, an upstream kinase of Elk-1 in the Bcr-Abl mediated regulatory pathway of PKC-é. This suggested that ERK1 was integral to the self-regulatory activity of PKC-é. In conclusion, we hypothesize that the self-regulatory mechanism of PKC-é is initiated by the translocation PKC-é into the nucleus where it activates ERK1. This promotes the activation of its downstream target Elk-1 which subsequently upregulates the expression of PKC-é

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