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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.
101

Elk and mule deer distributions after a cattle introduction in northern Arizona

McIntosh, Bruce John January 1981 (has links)
No description available.
102

Corridors and Elk Migration: A Comparative Analysis of Landscape Connectivity Models and GPS Data in the Greater Yellowstone Ecosystem

Chambers, Samuel Norton January 2015 (has links)
Landscape connectivity models aim to map the links or corridors that wildlife would or do use between patches of habitat. Migratory species such as elk traverse between such patches which serve as seasonal ranges. The goal of this study was to compare and contrast the suitability of several landscape connectivity models for describing and predicting migration in a long-distance migrant. We measured the suitability of connectivity models for covering and predicting the migratory movements of elk in the Greater Yellowstone Ecosystem. GPS point data was converted to sequential networks for multiple populations of elk. GPS data was also used to delineate the summer and winter ranges of each population. The kernel density of routes in the networks was measured for comparison to connectivity models. The ranges served as the patches to be connected by such models. A resistance surface was produced using reclassified landcover data for mapping habitat suitability and linear road data for human presence or obstruction to movement. Landscape connectivity was measured for eleven migratory elk populations using three distinct models. The first measured connectivity using circuit theory; the second, agent based modeling; the third, least cost corridors. The model results were compared to the migratory network density by measuring correlation. This was followed by a new method of measuring the influence of autocorrelation between the models and networks. Some of the models were then altered to test for suspected influences. This study shows that least cost corridors and circuit theory can are limited in their ability to predict the migratory movements between summer and winter ranges but only so much. They lack the ability to predict exploratory movements that do not link conspicuous ranges to each other. They also lack the ability to account for all avoidance behaviors in the landscape. Our results suggest that connectivity models need improvement by accounting for exploration outside of prime habitat. It also suggests connectivity models are not adequate predictors of migratory movements and not suited to conservation planning of migratory networks. This supports Sawyer's (et al. 2009) ungulate conservation planning of considering connectivity but basing priority on migratory landscape usage. It is assumed that fragmentation or loss in connectivity impedes seasonal migration, cutting off wildlife from resources (Rudnick et al. 2012). This study shows that migratory elk are actually using less than prime and supposedly fragmented habitat in migration and that there is more than connectivity at play.
103

Φυσική διασύνδεση της ERK με τον Elk-1 μέσω της FAK στα αιμοκύτταρα της μύγας της Μεσογείου / Physical association of ERK and Elk-1 through FAK in medfly haemocytes

Καποδίστρια, Αικατερίνη 15 January 2009 (has links)
Η FAK, οι MAPKs και ο μεταγραφικός παράγοντας Elk-1 έχει αναφερθεί ότι εμπλέκονται στις ίδιες κυτταρικές διαδικασίες, παρ’ όλα αυτά, η άμεση ή έμμεση αλληλεπίδρασή τους και οι ενδεχόμενες λειτουργίες τους δεν έχουν ακόμα τεκμηριωθεί. Σκοπός αυτής της διατριβής ήταν η περαιτέρω διερεύνηση των σηματοδοτικών μονοπατιών που ρυθμίζουν τη διαδικασία της κυτταροφαγίας και ειδικότερα την αποκάλυψη της φυσικής διασύνδεσης των παραπάνω σηματοδοτικών μορίων. Αρχικά, μελετήσαμε την υποκυτταρική κατανομή των FAK, ERK και Elk-1 στα αιμοκύτταρα της μύγας της Μεσογείου, παρουσία ή απουσία E. coli. Πειράματα ανοσοφθορισμού έδειξαν ότι οι FAK, MAPΚs και Elk-1 κατανέμονται ομοιόμορφα σε όλο το κύτταρο, όμως παρουσία E. coli, φωσφορυλιώνονται και σταδιακά εισέρχονται στον πυρήνα. Στη συνέχεια, με συνεστιακή μικροσκοπία δείχθηκε ότι παρουσία E. coli, οι FAK και ERK φωσφορυλιώνονται και συνεντοπίζονται στην περιφέρεια του κυττάρου. Βιοχημική προσέγγιση επιβεβαίωσε ότι μόνο οι φωσφορυλιωμένες FAK και ERK συμπλοκοποιούνται. Ακολούθως, η φυσική διασύνδεση της FAK και του Elk-1 διερευνήθηκε με ανοσοσυγκατακρήμνιση, αντίστροφη ανοσοσυγκατακρήμνιση, ανάλυση κατά Western και ανοσοφθορισμό. Από τα πειράματα αυτά φάνηκε συμπλοκοποίηση μεταξύ του Elk-1 ή του pSer383Elk-1 και της FAK όχι όμως και της pTyr397FAK. Το σύμπλοκο FAK/Elk-1 εντοπίζεται, κυρίως, στον πυρήνα. Τέλος, πειράματα συνεστιακής μικροσκοπίας έδειξαν ότι η ERK συν-εντοπίζεται με τον Elk-1 σε μικρό βαθμό, όμως ανοσοσυγκατακρήμνιση, αντίστροφη ανοσοσυγκατακρήμνιση και ανάλυση κατά Western δεν αποκάλυψαν κάποια φυσική διασύνδεση μεταξύ της ERK και του Elk-1. / Focal adhesion kinase (FAK), mitogen-activated protein kinases (MAPKs) and the nuclear transcription factor Elk-1 have been reported to be implicated in the same cellular processes, however, their direct or indirect interaction and potential function(s) has not been documented. The goal of this study was to explore further the signaling pathways that regulate the process of phagocytosis and specifically to show the physical association of the above signaling molecules. Initially, we explored the subcellular distribution of FAK, ERK and Elk-1 in medfly haemocytes, treated in the presence or absence of E. coli. Immunofluorescence analysis demonstrated that FAK, MAP kinases and Elk-1 appear to localize throughout the cytoplasm but in the presence of E. coli they are phosphorylated and gradually imported in the nucleus. Furthermore, confocal analysis showed that in the presence of E. coli, FAK and ERK are phosphorylated and co-localized in the periphery of the cell. Biochemical approaches confirmed that only phosphorylated FAK and ERK are physical associated. Moreover, the physical association of FAK and Elk-1 was explored, using co-immunoprecipitation, reciprocal co-immunoprecipitation, Western blot and immunofluorescence analysis. These experiments revealed an association between Elk-1 or pSer383Elk-1 and FAK but not with pTyr397FAK. The FAK/Elk-1 complex is found, mainly, in the nucleus. Finally, confocal analysis demonstrated that ERK co-localizes with Elk-1 at a low level but co-immunoprecipitation, reciprocal co-immuno-precipitation and Western blot did not reveal a physical association between ERK and Elk-1.
104

A grassland forage supply assessment in Southeast British Columbia with comparisons to current Rocky Mountain elk (Cervus canadensis nelsoni) and range cattle (Bos taurus) grazing pressure and analysis of productivity distinctions

Anaka, Tobi 15 June 2010 (has links)
Open grassland productivity was measured within adjacent East Kootenay range units to evaluate forage availability and calculate elk (Cervus canadensis nelsoni) and cattle (Bos taurus) sustainable carrying capacity targets. This research extends rangeland monitoring with an analysis of site differentiation and comparative grazing pressure to 2008 population estimates. Significant productivity differences were found between grass and shrubs for range units (p=0.024 and p<0.0001) and different biogeoclimatic zones (p=0.042 and p<0.0001). Notable grazing pressure distinctions occurred: cattle exceeded the Rampart Mayook carrying capacity, elk exceeded the Pickering Hills carrying capacity, and both species had sustainable populations within the Power Plant range unit. These results provide clear direction for stock management and offer valuable rangeland insight. Furthermore, the study introduces cover-percentage productivity estimation (CPPE), a simple grassland productivity assessment method. Pearson correlation coefficients were significant and high between productivity results and cover estimates, indicating that CPPE will be a useful field tool.
105

Habitat selection by sympatric ungulates in an agricultural landscape : implications for disease transmission and human-wildlife conflict

2013 January 1900 (has links)
As areas of agricultural production expand worldwide, complex zones of wildlife-agriculture interface present numerous benefits and challenges to farmers and wildlife managers. In western Canada, free-ranging elk (Cervus canadensis), mule deer (Odocoileus hemionus), and white-tailed deer (Odocoileus virginianus) make frequent use of cereal, oilseed, and pulse crops. However, cervid use of annual crops presents substantial socio-economic concerns for producers. Additionally, use of crops may facilitate cervids co-mingling and increase the risk of intra- and inter-specific transmission of chronic wasting disease (CWD). The purpose of my thesis research was to determine the key environmental factors influencing the selection of agricultural crops by elk, white-tailed deer, and mule deer, analyze overlap in species’ selection, and develop predictive models to identify the spatial distribution of crop damage risk. In this study, I analyzed 19,069 damage claims paid by Saskatchewan Crop Insurance Corporation to Saskatchewan farmers for confirmed losses to annual crops (cereals, oilseeds, pulses) from 2000-2012 by elk, mule deer, and white-tailed deer. These data were used to conduct species-specific ecological niche factor analyses (ENFAs), which relate habitat variables within damaged sites to that of the surrounding landscape. The key habitat variables influencing selection of annual crops were then incorporated into resource selection probability function (RSPF) models. These models characterize and predict the probability of crop damage by elk, mule deer, and white-tailed deer, and each possible dual species combination. By integrating damage probability values and historical monetary values of regional crop production, I evaluated the risk of annual crop damage by each of the three species, and dual species combinations, across all sections of agricultural land in Saskatchewan. The ENFAs revealed that elk and white-tailed deer selected for areas where a high proportion of farmland is seeded to oats, barley, canola, and alfalfa, while avoiding areas farther from protected areas, with a high density of paved or unpaved roads and a high proportion of open grassland. Alternately, mule deer favoured open grasslands, shrublands, and areas with a greater density of streams or water bodies, while avoiding areas where a high proportion of farmland is seeded to oats, canola, flaxseed, wheat, and barley. Areas at highest risk for annual crop damage by elk bordered the northern edge of the study area; mule deer damage risk was highest in south-western and central Saskatchewan; while white-tailed deer damage risk was highest in north-eastern and north-central areas of the province. Identifying these specific associations between landscape variables, rates of crop damage, and associated species overlap may provide an important opportunity for agencies to develop cooperative management strategies to efficiently allocate mitigation resources. Efforts to prevent the selection of cereal, oilseed, and pulse crops by free ranging elk, mule deer, and white-tailed deer in Saskatchewan could prove to be a valuable step in not only minimizing crop damage and maintaining wildlife tolerance in rural communities, but also in managing the spread of chronic wasting disease throughout western Canada.
106

Trophic cascades: Linking ungulates to shrub-dependent birds and butterflies

Teichman, Kristine J Unknown Date
No description available.
107

Cow elk ecology, movements and habitat use in the Duck Mountains of Manitoba

Chranowski, Daniel John 01 December 2009 (has links)
This study conducted baseline research to determine home range, movements and habitat selection of Manitoban elk (Cervus elaphus manitobensis) in the Duck Mountain (DM) of west-central Manitoba. Cow elk (n =22) were captured by helicopter net-gun and GPS radio-collared in 2005/06. Data was analyzed with ArcView 3.3 for Windows (ESRI). DM elk show selection for deciduous forest and avoidance of roads. Mean 100% MCP home ranges were 127.85 km2 with 95% and 50% adaptive kernel home range sizes of 58.24 km2 and 7.29 km2, respectively. Home range overlap occurs at all times of the year with many elk using farmland. Elk moved the least in late winter. Movements increased in the spring, declined in June with a gradual increase from July to October. Elk had generalized movement in southerly directions. No cow elk dispersed from the study area. Mean estimated calving date was June 3rd and mean estimated breeding date was September 27th. DM elk were found in mature deciduous/mixed-wood forest and shrub/grassland/prairie savannah ecosites but not found within 200 m of a road or water feature more often than expected by random. Elk were found in areas with <10% and >81% crown closure, on middle slopes and variable aspects. Elk displaced from forestry cut-blocks. Only 149 of 79,284 elk locations were within 100 m of a winter cattle operation. Recommendations to mitigate forestry and BTB impacts focus on riparian areas, road management, farming practices and hunting.
108

ELK CALF SURVIVAL, MORTALITY, AND NEONATAL HABITAT USE IN EASTERN KENTUCKY

Seward, Nathan W. 01 January 2003 (has links)
I estimated survival, cause-specific mortality, and neonatal habitat use of elk (Cervus elaphus nelsoni) calves in eastern Kentucky. I also measured habitat characteristics of elk parturition sites and annual calf production . Radio-collared females were fitted with vaginal implant transmitters and monitored for parturition behavior to locate, capture, and radio-collar calves during the springs of 2001 and 2002. Thirty-seven adult females with implant transmitters were translocated from Logan, Utah, to Addington Wildlife Management Area (WMA) in eastern Kentucky. Additional females from previous releases during 1997 and 1998 were monitored for parturition behavior. Mean calf production for all females monitored (n=77) was 66.2%. Parturition sites (n=10) were typically in closed-canopy hardwood forest within 152 m of a forest/grassland interface. Female selected sites with more boulders, andlt; 20 slope, a higher percentage of woody saplings, and thicker vegetation between 1.0 2.25 m in height compared to random sites. Twenty-seven calves were radio-collared and intensively monitored by ground and aerial telemetry. Mean annual survival was 0.766 ( 0.103). Coyote (Canis latrans) predation, meningeal worm (Parelaphostongylus tenuis), and human-caused mortality may slow population growth. Retention of implant transmitters for 40 cows ranged from 1 to 276 days (61.6 3.0). Only 2 implant transmitters worked as designed and led to calf captures. I had better success (n=25) capturing calves by monitoring parturition behavior and searching areas where pregnant cows were suspected to have given birth.
109

USING FORWARD-LOOKING INFRARED RADIOGRAPHY TO ESTIMATE ELK DENSITY AND DISTRIBUTION IN EASTERN KENTUCKY

Dahl, Lauren M. 01 January 2008 (has links)
Elk (Cervus elaphus) in eastern Kentucky appear to have increased in number since reintroduction in 1997, but rugged landscapes and cryptic elk behavior have precluded use of typical population survey methods to accurately estimate population size. In December 2006, I used forward-looking infrared radiography (FLIR) to survey the elk population in eastern Kentucky. Elk locations identified by FLIR were used to create a landscape based model to estimate the density distribution of elk within a 7,088 km2 core area of the elk restoration zone. FLIR detected 76% of elk groups of < 10 individuals and 100% of elk groups of ≥ 10 individuals. The density of elk was positively associated with the amount of herbaceous area, herbaceous edge, herbaceous area weighted mean patch fractal dimensions, proximity to release sites, the number of elk released at each site and urban core area index, and negatively associated with road density. My model estimated the elk population at 7,001 (SE = 772, 95% CI = 5,488- 8,514) individuals within the core area, 53% of which were < 10 km from release sites. The predicted elk distribution pattern and abundance estimate derived from this model will be important for wildlife managers in successfully managing the Kentucky elk population.
110

Life History of Dwarf Longnose Sucker (Catostomus catostomus) in the Elk River Watershed

Le Page, Paul S. January 2014 (has links)
In 2004, a population of dwarf longnose sucker was discovered co-existing with the normal form within the Elk River Watershed of south-eastern British Columbia. This thesis evaluated morphological, genetic and life history characteristics of this dwarf longnose sucker form to determine whether the dwarf morphotype warranted designation as an evolutionary significant unit and to determine any special habitat requirements. In addition to size, distinct morphological differences were indicated between Elk River Watershed dwarf and normal adult longnose sucker, with dwarf adults appearing to retain morphological features of juveniles and sharing morphological features with Salish sucker, which is a separate dwarf longnose sucker form that is considered endangered. Slight, but significant, genetic differences were indicated between Elk River Watershed dwarf and normal longnose sucker forms, and compared to Salish sucker, suggesting some basis for separate designation of the dwarf form. Dwarf longnose sucker are widespread in the Elk River Watershed, and most abundant in small, cool lentic water bodies that contained dense vegetative cover, potential oxycline fluctuation and/or limited fish species diversity. Dwarf adult longnose sucker showed some habitat preference differences compared to normal longnose sucker, with the findings suggesting that dwarf longnose sucker have adopted a more opportunistic life-history strategy than normal longnose sucker. It is postulated that an ontogenetic niche shift has allowed dwarf longnose sucker to more successfully exploit habitats experiencing periodic disturbances (e.g., hypoxia) that, in turn, has led to the occurrence of two longnose sucker morphotypes in the Elk River Watershed.

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