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Landslide occurrence in the Elk and Sixes River basins, southwest OregonMcHugh, Margaret H. 10 December 1986 (has links)
Timber management of coastal watersheds in southwest Oregon has
been complicated by the need to protect anadromous fish habitat from
accelerated stream sedimentation resulting from management activity.
The rugged terrain of the Elk and Sixes River basins is underlain by
the complex geological province of the Klamath Mountains, in which
landslides are a common, natural, and important process of sediment
production.
A landslide investigation, using sequential aerial photographs
which covered a time period of 37 years, was used to determine
relationships between mass-wasting, geologic types, and timber harvest
practices. Averaged over all rock types, harvested areas showed an
increase in failure rate of 7 times, and roaded areas an increase of
48 times that of forested terrain. Terrane underlain by dioritic
intrusions was the most sensitive to road-related activity, with an
increase in failure rate of up to 108 times that of comparable
unmanaged land.
The complexity of lithologies and deformational history in the
area strongly influence slope morphology, and produces characteristic
soil types which experience predictable modes and rates of slope
failure. Debris slides and torrents are the dominant form of
mass-wasting in dioritic and Cretaceous sedimentary terrane. Areas
underlain by more clay-rich metamorphic bedrock are prone to slumps
and planar streambank failures.
Stream morphology is profoundly influenced by both rock type and
geologic structure. Within an area characterized by steep, deeply
incised streams, several persistent low-gradient reaches were
delineated. These low-gradient stream reaches occur where (1) large
landslides have locally raised channel bed elevation and (2)
valley-floor widening has occurred in sheared rocks along fault zones
or in more readily eroded rock types upstream of rock types resistant
to fluvial erosion. / Graduation date: 1987
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A Managment Study of the Cache Elk HerdHancock, Norman V. 01 January 1955 (has links)
American elk, by virtue of their distribution, were the most cosmopolitan members of the cervid family at the time of white settlement of North America. At this early date elk were present in every major region of what is now continental United States, as well as in northern Mexico. They likewise were abundant in upper and lower Canada, though records do not corroborate their presence too far north on the Atlantic coast. Although generally existent throughout the western states, elk were sparsely distributed in Nevada, southern Utah, and most of Arizona and New Mexico. Paucity of elk was also noted in eastern portions of Washington and Oregon.
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Population Distribution and Seasonal Resource Selection by Elk (Cervus elaphus) in Central OntarioMcGeachy, David N. C. 14 April 2014 (has links)
Understanding population structure and resource selection are essential for wildlife management and conservation. I assessed the population structure and resource selection of elk (Cervus elaphus) in central Ontario. I used fuzzy and hierarchical cluster analyses to elucidate elk population structure based on spatial data collected from 41 radio-collared elk. I assessed impacts of habitat quality on space use using the minimum convex polygon (MCP) and fixed kernel methods. I evaluated resource selection by elk in winter, spring, summer, and fall, from December 2011 to August 2013, using resource selection functions (RSF’s). I used a generalized linear mixed model (GLMM) to evaluate resource selection functions and used Akaike information criterion (AICc ) to select the best model of 20 candidate models constructed a priori. Models included parameters representing resources known to be important to elk: elevation, aspect, slope, distance to roads and water, and habitat. Both fuzzy and hard clustering indicated that elk in Central Ontario occur in a metapopulation that includes 5 subpopulations. The largest cluster consisted of a core group of 22 radio-collared elk located in Burwash with several satellite subpopulations spread along a 50km long north-south axis and a small subpopulation to the west located in Worthington. Survival rates among subpopulations were similar ranging from 0.71 to 0.83; however, anthropogenic causes of mortality were predominant only in the Burwash subpopulation. Space use and density of elk differed between core and satellite subpopulations. Resource selection by elk differed by time of day and season. In all seasons, elk selected open habitats at night and more forested areas during the day. Elk avoided areas close to roads in spring, but selected them in winter at night. Elk selected higher elevations in winter and for south facing slopes in spring and fall. Elk displayed strong crepuscular activity patterns in all seasons; however, movements were limited in winter. Understanding population structure is important in order to develop appropriate management plans. My results support the conclusion that population structure can be reliably assessed using spatial data. Resource selection is a dynamic process that changes with seasons, as well as animal activity across the diel period. Resource selection should include time of day in order to obtain a complete picture of resources important to a particular species and to support the conservation of habitats used for various animal activities.
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Aversive conditioning on horse back: A management alternative for grassland systems threatened by sedentary elk populationsSpaedtke, Holger Ronald Unknown Date
No description available.
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Mcl-1 in breast cancer: regulation by the EGF receptor family and role in cell survival and drug resistanceBooy, Evan Paul 10 January 2011 (has links)
Myeloid Cell Leukemia-1 (Mcl-1) is a widely expressed anti-apoptotic member of the Bcl-2 family that is elevated in a variety of tumour types including breast cancer. Mcl-1 promotes tumour cell survival and drug resistance and was a mechanism of resistance to first generation Bcl-2 family inhibitors. To determine the significance of Mcl-1 in breast cancer, we evaluated the regulation of Mcl-1 by signalling via the epidermal growth factor receptors (EGFRs). EGFR signalling is frequently deregulated in breast cancer and leads to increased proliferation and survival of tumour cells. We aimed to determine whether Mcl-1 is a critical downstream effector of this pathway and therefore an important therapeutic target. We found that Mcl-1 protein and messenger RNA levels were rapidly induced upon stimulation of breast cancer cells with epidermal growth factor. This induction was blocked by inhibitors of the Ras/Raf/Mek/Erk signalling cascade and was dependent upon activation of the transcription factor Elk-1. We found Mcl-1 to be an essential survival protein, as targeted knock-down with small interfering RNA alone was sufficient to induce apoptosis. Mcl-1 may be critical for the survival advantage conferred by EGFR activation, as prevention of its up-regulation by Mek/Erk inhibitors significantly reduced the drug resistance conferred by EGF. Furthermore, we found a correlation between phosphorylated Elk-1 and Mcl-1 protein levels in breast tumour samples. Therefore, we conclude that Mcl-1 is an important downstream effector of survival and drug resistance mediated by elevated EGF signalling, making it an important therapeutic target in breast cancer.
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EFFECTS OF A RESTORED ELK POPULATION ON SOILS, VEGETATION, AND WATER QUALITY IN EASTERN KENTUCKYTer Beest, Julia M. 01 January 2005 (has links)
A restored elk (Cervus elaphus) population in eastern Kentucky may be affecting ecosystem processes in a landscape composed of reclaimed grassland expanses and isolated forest remnants. Elk routinely select forested ridge-tops as resting and ruminating sites. These locations are characterized by sparse or absent leaf litter, trampled and diminished vegetation, large deposits of dung, and urine-saturated soils. In fall 2003, a series of fenced ungulate exclosures were constructed; 8 on highly disturbed forested ridge-tops and 8 on reclaimed grasslands. Soil analyses measured % moisture, pH, total nitrogen, total carbon, ammonium, nitrate, phosphorus, and major extractable cations in 0-10 cm and 10-20 cm cores. Litter depths and percentages of bare ground, vegetative cover, litter cover, and woody debris were measured. Sediment and water samples were collected monthly from sediment traps on reference and experimental ridge-tops. Studentfs t-tests were used to determine significance (p . 0.10) between treatments. Disturbed ridge-tops had higher soil ammonium (0.68 mg/kg, 10-20 cm) than reference sites (0.25 mg/kg) in spring 2004 and lower ammonium (0.72 mg/kg, 0-10 cm; 0.44 mg/kg, 10-20 cm) than reference sites (1.80 mg/kg, 0-10 cm; 0.94 mg/kg, 10-20 cm) in summer 2004. Total carbon was higher inside (67.57 g/kg, 0-10 cm) than outside (45.38 g/kg) of ridge-top exclosures in fall 2004. Soil moisture, litter depths, and vegetative cover were generally lower, while % bare ground was higher on disturbed ridge-tops. Sediment collected from traps averaged 2.21g/m2 inside exclosures, 2.86 g/m2 outside exclosures, and 0.39 g/m2 on reference ridge-tops. These data suggest that this reintroduced species is changing several attributes of the Cumberland Plateau landscape. The lack of a predator such as the gray wolf (Canis lupis) or cougar (Puma concolor) likely contributes to the development of habitual elk use of landscape features such as remnant ridge-top forests. Such concentrated use may create conditions for the colonization of certain plant species including rare natives and invasive exotics. Continued monitoring of high use areas is recommended so that managers can fully understand the long-term impact of the return of this large, gregarious herbivore, and that appropriate management actions can be developed to promote native biodiversity.
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MATERNAL ANTIBODY TRANSFER AND MENINGEAL WORM INFECTION RATES IN KENTUCKY ELKBowling, Willie Elwood 01 January 2009 (has links)
Elk (Cervus elaphus) were historically present throughout Kentucky, but were extirpated by the mid 19th century. Kentucky Department of Fish and Wildlife Resources initiated elk reintroduction efforts in 1997, resulting in a self-sustaining population. I designed this project to study the effects of a parasitic nematode, meningeal worm (Parelaphostrongylus tenuis), on Kentucky’s elk herd. I examined potential maternal transfer of P. tenuis antibodies to elk calves, and investigated the relationship between elk habitat use and meningeal worm infection. I captured neonatal elk in 2004-06, fitted them with VHF transmitters, and collected blood samples for an enzyme-linked immunosorbent assay (ELISA) to determine P. tenuis infection. I monitored animals to determine habitat use, and attempted to recapture each individual to collect a follow-up blood sample. I found substantial rates of maternal meningeal worm antibody transfer (55%) over the course of the study. Neither sex nor predicted birth weight was associated with increased likelihood of obtaining maternal antibodies. Habitat variables associated with P. tenuis infection included herbaceous, shrub, and bare cover types, herbaceous mean core area, forest edge density, and forest mean core area. Confounding variables complicated habitat data analysis, but high rates of maternal P. tenuis antibody transmission suggested that meningeal worm infection does not threaten the long-term viability of the Kentucky elk herd.
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The epidemiology of bovine tuberculosis (Mycobacterium bovis) in the Greater Riding Mountain Ecosystem2015 January 1900 (has links)
The overall objective of this thesis is to provide an enhanced understanding of the epidemiology of Mycobacterium bovis in the Greater Riding Mountain Ecosystem (GRME) and provide a scientific basis for disease management from a systems perspective now and into the future. M. bovis prevalence has been consistently higher in elk compared to white-tailed deer, and higher within a defined Core area compared to areas outside. Prevalence in both species declined significantly between 2003 and 2013. Only one infected elk was detected in 2013; the last infected white-tailed deer was detected in 2009 and the last infected cattle herd was detected in 2008. Parallel interpretation of three blood-based assays resulted in effective selective culling of elk within Riding Mountain National Park (RMNP) with predictive value negative of 100%. A lymphocyte stimulation test (LST) was the most sensitive single blood-based assay, but was difficult to perform under field conditions. Combinations of humoral antibody tests and cell-mediated tests performed better than any single test, likely detecting the broad spectrum of host pathology present. Seven of 14 risk factors were identified for wild cervids testing culture positive with the three being most strongly associated with culture positivity being geographical location (within core area), elk density and year category (sampling phase). Age, sex, and surveillance method were also significant factors, but species was not. A rapid decline in elk density in combination with fencing of hay storage yard and non-selective culling were likely key factors resulting in the M. bovis prevalence decline observed in elk, and an overall decline in prevalence from 1997 for both species. Elk were the primary reservoir species in this episystem, but are now considered a spillover host, while white-tailed deer have always been a spillover host due to lower densities and shorter life expectancy. Very limited strain diversity exists within the GRME with one spoligotype restricted to cattle and associated with a limited outbreak in five herds in the early 1990’s, and three other shared strains between cattle and wildlife. A single monomorphic type was present in white-tailed deer. Significant spatial overlap of wildlife and cattle isolates delineated a core area where management activities are now focused. The relative simplicity of this episystem has allowed significant progress on control and management to be achieved, despite being located within a national park. Wildlife surveillance will need to continue until at least 2022 in order to achieve a 95% probability of freedom using three different surveillance streams. Latent cases are likely to be extremely rare in future and unlikely to result in ongoing transmission as the factors that created this wildlife reservoir no longer exist. Wild cervids should not be considered ideal maintenance hosts for M. bovis in North America but rather facultative hosts; acting either as a reservoir or spillover host dependent on regional/local density and presence/absence of baiting and feeding.
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Mapping elk distribution on the Canadian prairies: Applying local knowledge to support conservation2014 June 1900 (has links)
Once abundant across the Great Plains of North America, prairie-parkland elk (Cervus canadensis manitobensis) underwent a catastrophic population collapse and dramatic contraction of their overall range through the late 1800’s and the early 1900’s due to habitat loss (primarily from agricultural expansion) and unregulated hunting. Populations were able to recover in some areas following new hunting regulations and the establishment of protected areas. Prior to this study, the current distribution of prairie parkland elk was poorly understood, though it was established that they were largely relegated to large protected areas and made use of adjacent agriculture dominated landscapes. In order to effectively manage prairie-parkland elk so populations remain resilient to ongoing habitat loss, population reduction and disease risks, detailed mapping of their range and an understanding of the environmental factors most important to elk is essential. The purpose of my thesis is to characterize elk distribution and resource selection patterns in the prairie-parkland of Saskatchewan and Manitoba, Canada, at a landscape scale and assess the implications of distribution for species persistence, by using both local ecological knowledge (LEK) and biological research techniques in tandem.
Integrating LEK with more conventional biological research can provide complementary data at contrasting time and spatial scales and facilitates comparison of multiple independent datasets. Furthermore, LEK research creates important opportunities to engage stakeholders in contributing knowledge and may facilitate relationships and contribute toward more effective resource management. I used three sets of biotelemetry-collar data from across Saskatchewan and Manitoba (n = 328 collared elk; 1998–2012), in conjunction with LEK from hunters, biologists and enforcement officers (n = 71 participants) to create a series of resource selection functions (RSFs) characterizing elk distribution across Saskatchewan and Manitoba. I gathered LEK in workshops where participatory mapping was conducted with local experts across the study area. The RSF analysis determined that prairie-parkland elk selected locations close to protected areas and far from high road density. Elk also selected areas with moderate amounts of mixed-wood and deciduous forests and herbaceous vegetation. Models developed with LEK only, biotelemetry collar data only and a combined dataset were all validated against an independent dataset of elk crop damage locations. All models predicted elk presence well. The RSF scores of the LEK only and radio-collar only models were not significantly different.
Successful conservation management requires identifying which areas are most important to a species, and assessing if these areas are vulnerable to threats, as well as balancing human resource needs. Using the RSF-based maps of prairie-parkland elk distribution, I identified locations of high quality habitat (top 10% of RSF values) and determined which of those areas were vulnerable to agricultural expansion, forestry, disease, and hunting. I identified 81 high quality habitat areas with a combined total area of 30 753 km2. One or more vulnerability factor impacted 87% of the identified core area. High quality areas were clearly clustered around the boreal-prairie transition zone and large protected areas. The majority (88%) of high quality core areas were located within protected areas. A connectivity analysis using least cost path analysis determined that core habitat areas endemic with chronic wasting disease (CWD) in wild elk are highly connected to other high quality habitat areas. CWD thus has the potential to reduce cervid populations within the study area.
My thesis results highlight that prairie-parkland elk populations in Saskatchewan and Manitoba remain threatened by habitat loss and disease, and emphasize the need for habitat conservation to prevent further population reduction. While elk populations have regained a small fraction of the range lost at the turn of the last century, they have not been able to re-establish with much success in the prairie portion of their range. I also determined that LEK can be as effective as conventional biological research approaches to develop RSFs. I also confirmed that stakeholders within the study are knowledgeable about elk behaviour. The distribution maps and identified areas of priority concern created in this thesis can provide important insights to support the management and maintenance of abundant elk populations.
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Mcl-1 in breast cancer: regulation by the EGF receptor family and role in cell survival and drug resistanceBooy, Evan Paul 10 January 2011 (has links)
Myeloid Cell Leukemia-1 (Mcl-1) is a widely expressed anti-apoptotic member of the Bcl-2 family that is elevated in a variety of tumour types including breast cancer. Mcl-1 promotes tumour cell survival and drug resistance and was a mechanism of resistance to first generation Bcl-2 family inhibitors. To determine the significance of Mcl-1 in breast cancer, we evaluated the regulation of Mcl-1 by signalling via the epidermal growth factor receptors (EGFRs). EGFR signalling is frequently deregulated in breast cancer and leads to increased proliferation and survival of tumour cells. We aimed to determine whether Mcl-1 is a critical downstream effector of this pathway and therefore an important therapeutic target. We found that Mcl-1 protein and messenger RNA levels were rapidly induced upon stimulation of breast cancer cells with epidermal growth factor. This induction was blocked by inhibitors of the Ras/Raf/Mek/Erk signalling cascade and was dependent upon activation of the transcription factor Elk-1. We found Mcl-1 to be an essential survival protein, as targeted knock-down with small interfering RNA alone was sufficient to induce apoptosis. Mcl-1 may be critical for the survival advantage conferred by EGFR activation, as prevention of its up-regulation by Mek/Erk inhibitors significantly reduced the drug resistance conferred by EGF. Furthermore, we found a correlation between phosphorylated Elk-1 and Mcl-1 protein levels in breast tumour samples. Therefore, we conclude that Mcl-1 is an important downstream effector of survival and drug resistance mediated by elevated EGF signalling, making it an important therapeutic target in breast cancer.
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