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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.
21

Interaction Between Winter Dominance and Territory Defense in Male Pronghorn Antelope, Antilocapra Americana

Gunnels, Charles William, IV 01 May 1999 (has links)
In a territorial population of pronghorn from Antelope Island, UT, interaction between male dominance and territory defense was examined. High-ranking males were more likely to defend territories. Closely ranked animals engaged in more dominance interactions than distantly ranked individuals, and middle-ranked animals were involved in disproportionately more interactions than either high- or low-ranking animals. Large males possessed large horns and prongs as well as small cheek patches. Results from a factor analysis suggested that large males defended territories with a high density of sage. However, in this study, we did not observe pronghorn feed on sage during the territorial season. Though male pronghorn practiced resource defense polygyny, large, dominant males did not defend territories with a high density of green vegetation or green forbs. Large males appeared to defend territories with low visibility. In 1996, intruders entered areas that contained females throughout the territorial season. During the next year, highly visible, small territories received the most intrusions. Together, these observations suggest defense of tactical locations. Defending a tactical location may help females avoid harassment and males hide the presence of females. Different populations of pronghorn practice different mating systems. To understand this variation, we examined the behavior patterns/rates of individual territorial and bachelor males. The highest rates of activity and behavior patterns occurred in March/April and in September. Territorial males cheek rubbed at a higher rate than bachelors. Territorial males were more active and SPUD (sniff, paw, urinate, and defecate) marked at a higher rate than bachelor males in 1996. After the formation of a bachelor herd in 1997, bachelor males showed higher rates of male-male interactions than territorial males. Territorial males maintained the same activity and behavioral rates in the presence and absence of females. Dispersion pattern of scent marks was more clumped in the presence of females. These findings suggest cheek rubs function more as a space-claiming behavior while SPUD marking is more strongly associated with male-male interactions. Comparison to male behavior in nonterritorial populations indicates that the behavioral mechanisms are present in all populations to accommodate shifts in social systems.
22

Home range and resource use of sable antelope in the Okavango Delta

Hensman, Michael C. 15 January 2013 (has links)
A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Masters in Science Centre for African Ecology, School of Plant Animal and Environmental Sciences, 2011. / Habitat selection occurs across a range of different spatial scales and is influenced by a variety of factors, ultimately determining how animals distribute themselves across the landscape. Studying the decisions that an individual animal makes across different levels of selection, from its choice in dietary item to predator avoidance strategies, is a fundamental link in understanding the response of groups of animals and ultimately entire populations that may provide insight into population performance. The study formed part of a broader study focused on the decline of rare antelope species. Specifically this study was aimed at establishing the home range and resource use of sable antelope in a region where they were initially expected to be thriving. The levels of selection covered in this study are: the location of home ranges of an individual or social group within the landscape; the use of various habitat components within the home range; and the procurement of food items within those habitats. At the highest level, the broad objectives were (1) to determine where sable occupied home ranges within the landscape, indicating the suitability of various landscape units to sustain sable populations and (2) to determine the relative use of habitat types within those home ranges that may enable sable to avoid predation and acquire resources required to survive and reproduce. At the lowest level of selection the characteristics of forage selection and how the grass quality in the different vegetation types during different seasons affects the success of sable herds was explored. The broad objectives were (1) to determine the effect of seasonal flooding and rainfall on grass greenness in the floodplains and upland vegetation types and the consequent use of those vegetation types by sable antelope and (2) to determine how exploitation of resources in the floodplains and in the uplands contributed to the nutritional status of sable. I additionally quantified the time spent browsing and determined the composition of the browse component of the diet of sable. Adult female sable from each of three adjacent sable herds were fitted with GPS collars providing hourly GPS co-ordinates. Adaptive LoCoH was used to determine home range location and annual, seasonal and core home range extents. A vegetation map was created and the number of GPS locations within each vegetation type was counted to determine their relative use in relation to availability within the home ranges. GPS collars were used to locate herds daily so that foraging observations of browsing and characteristics of the grasses grazed could be attained. Acceptability and dietary contributions of grass species and browse were determined for each sable herd during different seasons. The availability of grass species on the floodplain grasslands and in the upland grasslands and woodlands was estimated. Water and the availability of key resources posed a constraint on where sable home ranges were established. Sable simply did not occupy the region in the north of the study area further than 7 km from permanent water and floodplain grasslands. Herds generally avoided open savanna, mopane woodlands and Kalahari apple-leaf woodlands characterised by sparse grass cover, particularly during the dry season. Home ranges were relatively small compared 4 to the range estimates from herds in Kruger National Park. There was no obvious seasonal difference in home range extent nor were there large areas of overlap between home ranges of adjacent herds. Observations during the study indicated that competitor species, including zebra and wildebeest, concentrated on the floodplain grasslands. Throughout the year H. dissoluta was the most strongly favoured grass species and contributed most to the diet of the sable herds in both the wet and dry season. During the dry season sable herds expanded their diet to include Aristida stipitata and Aristida meridionalis which are generally considered poor forage value species for cattle but that retained some greenness. Additionally, the contribution of browse, especially the leaves of Croton megalobotrys, Philenoptera nelsii and Combretum mossambicense and the flowers of Kigelia africana, constituted an important bridging resource during the extended dry season. Crude faecal protein levels remained above the suggested maintenance levels throughout the annual cycle. Crude faecal protein levels were elevated prior to calving when sable spent more time foraging on the floodplain grasslands where high value forage species such as Paspalum scrobiculatum, Panicum repens and Urochloa mossambicense and sedges were eaten. Indications are that the constraint posed by the distribution of water within the landscape, rather than resource limitations within occupied home ranges, are the primary limitation to population performance in the Kwedi concession. / Wilderness Safari, the Wilderness Wildlife Trust, the Conservation Foundation, Classic Africa and National Research Foundation (NRF) of South Africa.
23

Die ekologie van die swartwitpens in die Sandveld Natuurreservaat, Vrystaat Provinsie (Afrikaans)

Jooste, Madaleinn Heleen 03 April 2006 (has links)
Please read the abstract in the section 00front of this document / Dissertation (MSc Wildlife Management)--University of Pretoria, 2006. / Animal and Wildlife Sciences / unrestricted
24

Shaping an Iconic Species : From the giant panda to the red panda and the Tibetan antelope / Skapandet av en ikonisk art : från jättepandan till den röda panda och den tibetanska antilopen

Huang, Kefan January 2020 (has links)
This thesis is based and developed on the ambiguous and open conception, iconic species, which reveals the relationship between human society and non-human species that goes be- yond its biological status. From the case of the giant panda, I attempt to deconstruct the shap- ing process of an iconic species from multiple perspectives, which includes how a specific cultural context, or a specific historical period contributes to the shaping process and how the government and the public diverge or even clash around the shaping process. Then, I introduce my fieldwork where I through observing both giant pandas and red pandas in the exhibition centres called panda bases to analyse the encountering an iconic species in reality and their different influences on public awareness of the wildlife conservation. I also attempt to explore the various representative forms of an iconic species such as the Tibetan antelope ranging from the mascot to the film and follow the changes of its symbolic meanings in different forms. In conclusion, the thesis is aimed to reflect the hybrid features of the iconic species and pro- vide in-depth interpretation of the endless interactions between the human beings and other species.
25

Breeding season habitat use and response to management activities by greater sage-grouse on Sheldon National Wildlife Refuge, Nevada

Davis, Dawn M. 06 June 2002 (has links)
Greater Sage-Grouse (Centrocercus urophasianus) have experienced declines throughout their range over the last 50 years. Long-term declines in sage-grouse abundance in Nevada and Oregon have been attributed to reduced productivity. From 1995-1997, sage-grouse production on Sheldon National Wildlife Refuge (SNWR), Nevada was greater compared to Hart Mountain National Antelope Refuge (HMNAR), Oregon. Specific causes for the difference were unknown. Thus, the objectives were to: 1) Determine sage-grouse breeding season habitat use (especially with regard to wildfire) on SNWR; 2) Evaluate reproductive parameters to discern differences between SNWR and HMNAR; 3) Compare habitat components which may relate to differences in sage-grouse reproductive success on SNWR and HMNAR; and 4) Establish hematological and serum chemistry reference ranges for sage-grouse hens to assess physiological condition. Cover type was important in selection of nest sites at SNWR; however, nest cover did not affect nesting success and nest-site selection was not related to experience. Vegetative characteristics at successful nest sites were similar to unsuccessful nests but nest sites had greater amounts of tall residual grass (���18 cm) and medium height shrub cover (40-80 cm) than at random sites. Broods used areas with greater forb cover than random sites, indicating use was influenced by availability of forbs. Plant communities in wildfire and associated control sites did not differ appreciably in species composition. Although burning had little stimulatory effect on total forb cover 10-12 years post-burn, alteration of the sagebrush community did not limit sage-grouse use for successful nesting and brood-rearing. Fire did not negatively impact arthropod abundance. Differences in habitat use and sage-grouse productivity between SNWR and HMNAR may be related to differences in forb availability. Forb cover was greater at HMNAR than at SNWR for all cover types. Correspondingly, home range size for sage-grouse broods was greater on SNWR than at HMNAR. Nutrient analysis of forbs indicated higher crude protein, potassium, and magnesium levels at HMNAR than at SNWR; however, these nutrients are not likely to be deficient in most sage-grouse diets. Thus sagebrush-steppe communities supporting these forbs likely meet the dietary nutritional requirements of sage-grouse. Although blood calcium and uric acid levels were greater in sage-grouse hens on HMNAR than at SNWR, differences were attributed to capture date. Furthermore, physiological condition did not affect a hen's ability to nest successfully, nor was condition related to a hen's ability to recruit chicks to 1 August. Causes of sage-grouse decline are varied, but ultimately they are habitat based. Comparisons of reproductive parameters and habitat evaluations, combined with sage-grouse physiology data, may provide insight into habitat differences between study areas not previously recognized. Land management practices (e.g., prescribed fire) which recast the balance of native herbaceous species in degraded big sagebrush communities, may be necessary in the restoration of sagebrush-steppe ecosystems, and ultimately, the recovery of sage-grouse populations. / Graduation date: 2003
26

Habitat Selection by Two K-Selected Species: An Application to Bison and Sage Grouse

Kaze, Joshua Taft 01 December 2013 (has links) (PDF)
Population growth for species with long lifespans and low reproductive rates (i.e., K-selected species) is influenced primarily by both survival of adult females and survival of young. Because survival of adults and young is influenced by habitat quality and resource availability, it is important for managers to understand factors that influence habitat selection during the period of reproduction. My thesis contains two chapters addressing this issue for K-selected species in Utah. Chapter one evaluates habitat selection of greater sage-grouse (Centrocercusurophasianus) on Diamond Mountain during the critical nesting and brood-rearing period. Chapter two address selection of birth sites by bison (Bison bison) on Antelope Island, Utah. We collected micro-habitat data for 88 nests and 138 brood locations of greater sage-grouse from 2010-2012 to determine habitat preferences of nesting and brooding sage-grouse. Using random forests modeling techniques, we found that percent sagebrush, percent canopy cover, percent total shrubs, and percent obscurity (Robel pole) best differentiated nest locations from random locations with selection of higher values in each case. We used a 26-day nesting period to determine an average nest survival rate of 0.35 (95% CI = 0.23 – 0.47) for adults and 0.31 (95% CI = 0.14 – 0.50) for juvenile grouse.Brood sites were closer to habitat edges, contained more forbs and less rock than random locations. Average annual adult female survival across the two-year study period was 0.52 (95% CI= 0.38 – 0.65) compared to 0.43 (95% CI= 0.28 – 0.59) for yearlings.Brooding and nesting habitat at use locations on Diamond Mountain met or exceeded published guidelines for everything but forb cover at nest sites. Adult and juvenile survival rates were in line with average values from around the range whereas nest success was on the low end of reported values. For bison, we quantified variables surrounding 35 birth sites and 100 random sites during 2010 and 2011 on Antelope Island State Park. We found females selected birth sites based on landscape attributes such as curvature and elevation, but also distance to anthropogenic features (i.e., human structures such as roads or trails). Models with variables quantifying the surrounding vegetation received no support.Coefficients associated with top models indicated that areas near anthropogenic features had a lower probability of selection as birth sites. Our model predicted 91% of observed birth sites in medium-high or high probability categories. This model of birthing habitat, in cooperation with data of birth timing, provides biologists with a map of high-probability birthing areas and a time of year in which human access to trails or roads could be minimized to reduce conflict between recreation and female bison.
27

Using Remote Cameras to Estimate the Abundance of Ungulates

Taylor, Jace C 01 December 2017 (has links)
Many wildlife populations globally are experiencing unprecedented declines, and without accurate and precise estimates of abundance, we will not be able to conserve these vulnerable species. Remote cameras have rapidly advanced as wildlife monitoring tools and may provide accurate and precise estimates of abundance that improve upon traditional methods. Using remote cameras to estimate abundance may be less expensive, less intrusive, less dangerous, and less time consuming than other methods. While it is apparent that remote cameras have a place in the future of wildlife monitoring, research, and management, many questions remain concerning the proper use of these tools. In an effort to answer some of these questions, we used remote cameras to study a population of Rocky Mountain bighorn sheep (Ovis canadensis) in Utah, USA from 2012 to 2014. In Chapter 1, we compared methods using remote cameras against 2 traditional methods of estimating abundance. In Chapter 2, we evaluated the relationship between deployment time of cameras and proportion of photos needed to be analyzed to obtain precise estimates of abundance. We found that methods using remote cameras compared favorably to traditional methods of estimating abundance, and provided a number of valuable advantages. In addition, we found that remote cameras can produce precise estimates of abundance in a relatively short sampling period. Finally, we identified the optimal sampling period to produce precise estimates of abundance for our study population. Our findings can help researchers better utilize the potential of remote cameras, making them a more suitable alternative to traditional wildlife monitoring.
28

Using Remote Cameras to Estimate the Abundance of Ungulates

Taylor, Jace C 01 December 2017 (has links)
Many wildlife populations globally are experiencing unprecedented declines, and without accurate and precise estimates of abundance, we will not be able to conserve these vulnerable species. Remote cameras have rapidly advanced as wildlife monitoring tools and may provide accurate and precise estimates of abundance that improve upon traditional methods. Using remote cameras to estimate abundance may be less expensive, less intrusive, less dangerous, and less time consuming than other methods. While it is apparent that remote cameras have a place in the future of wildlife monitoring, research, and management, many questions remain concerning the proper use of these tools. In an effort to answer some of these questions, we used remote cameras to study a population of Rocky Mountain bighorn sheep (Ovis canadensis) in Utah, USA from 2012 to 2014. In Chapter 1, we compared methods using remote cameras against 2 traditional methods of estimating abundance. In Chapter 2, we evaluated the relationship between deployment time of cameras and proportion of photos needed to be analyzed to obtain precise estimates of abundance. We found that methods using remote cameras compared favorably to traditional methods of estimating abundance, and provided a number of valuable advantages. In addition, we found that remote cameras can produce precise estimates of abundance in a relatively short sampling period. Finally, we identified the optimal sampling period to produce precise estimates of abundance for our study population. Our findings can help researchers better utilize the potential of remote cameras, making them a more suitable alternative to traditional wildlife monitoring.
29

Quantification of potential elemental impact of a munitions production and testing facility on its immediate surroundings / Unique Janse van Rensburg

Janse van Rensburg, Unique January 2010 (has links)
The study attempted to quantify the elemental concentrations and possible accumulation levels in the antelope's organ tissue at Rheinmetal Denel Munitions (RDM), as well as to correlate the findings with the surrounding environment. To achieve this, the elemental concentrations within the kidney, liver and lung tissue of the antelope, and environmental factors such as the soil, vegetation and waterholes were quantified. STATISTICA was used to determine meaningful differences between variables and Canoco to determine the relationship between the different datasets. PCA analyses of the vegetation confirmed that the natural slope at RDM could have contributed to the distribution and variation of the elemental concentration. It became apparent that positive associations existed between the liver tissue and the K, the kidney tissue and Ni and Cd, and the lung tissue had a positive association with Mg, Mn, V, Rb and Co elemental concentrations. It became evident in this study that the elemental concentrations of Al and Ni were higher in the liver and kidney tissue of the antelope than the recommended concentration for livestock (Puls, 1994). The elemental concentration of Al, Ca, Fe and Mn also exceeded the recommended elemental concentration for livestock, in the water sampled at RDM (Puls, 1994). Four distinct areas were identified within the study area, the area above the factory, the area under the factory, the testing area and the area under the factory. Significant differences between the testing area and the area under the factory were found regarding the Tl, Ag, Hg and B elemental concentrations in the vegetation. Furthermore, it became apparent that the amount of precipitation could have contributed to the variation of the elemental concentrations and distribution in the study area as well as in the organ tissue of the antelope. / Thesis (M.Sc. (Environmental Science and Management))--North-West University, Potchefstroom Campus, 2011.
30

Quantification of potential elemental impact of a munitions production and testing facility on its immediate surroundings / Unique Janse van Rensburg

Janse van Rensburg, Unique January 2010 (has links)
The study attempted to quantify the elemental concentrations and possible accumulation levels in the antelope's organ tissue at Rheinmetal Denel Munitions (RDM), as well as to correlate the findings with the surrounding environment. To achieve this, the elemental concentrations within the kidney, liver and lung tissue of the antelope, and environmental factors such as the soil, vegetation and waterholes were quantified. STATISTICA was used to determine meaningful differences between variables and Canoco to determine the relationship between the different datasets. PCA analyses of the vegetation confirmed that the natural slope at RDM could have contributed to the distribution and variation of the elemental concentration. It became apparent that positive associations existed between the liver tissue and the K, the kidney tissue and Ni and Cd, and the lung tissue had a positive association with Mg, Mn, V, Rb and Co elemental concentrations. It became evident in this study that the elemental concentrations of Al and Ni were higher in the liver and kidney tissue of the antelope than the recommended concentration for livestock (Puls, 1994). The elemental concentration of Al, Ca, Fe and Mn also exceeded the recommended elemental concentration for livestock, in the water sampled at RDM (Puls, 1994). Four distinct areas were identified within the study area, the area above the factory, the area under the factory, the testing area and the area under the factory. Significant differences between the testing area and the area under the factory were found regarding the Tl, Ag, Hg and B elemental concentrations in the vegetation. Furthermore, it became apparent that the amount of precipitation could have contributed to the variation of the elemental concentrations and distribution in the study area as well as in the organ tissue of the antelope. / Thesis (M.Sc. (Environmental Science and Management))--North-West University, Potchefstroom Campus, 2011.

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