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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.
11

Monitoramento de espécie guarda-chuva Puma concolor (Felidae – Mammalia Carnivora) empregando amostras não invasivas /

Souza, Renato Marcelo Ferreira de. January 2018 (has links)
Orientador: Lígia Souza Lima Silveira da Mota / Resumo: O Brasil é um país megadiverso detentor de grande parte da riqueza ecológica do mundo, porém seus biomas, importantes devido aos serviços ecossistêmicos, sofrem com a pressão antrópica. Assim, os grandes predadores, que possuem efeito regulatório no ecossistema, geram conflitos direto com o homem. O Puma concolor é um predador generalista, atuando no perfil trófico onde reside. Estudos de populações in situ são importantes na elaboração de planos de manejo e a utilização de amostras não invasivas nos permitem ter acesso a informações biológicas a baixo custo. O objetivo deste trabalho foi avaliar o uso de amostras não invasivas para contribuir com informações nos planos conservacionistas da região. Foram percorridas bordas de mata e áreas de transição da APA-Botucatu. As amostras de fezes encontradas foram georreferenciadas, coletadas, selecionadas, fotografadas, classificadas e seu DNA extraído por meio da técnica empregando fenol/clorofórmio. O DNA obtido foi quantificado em espectrofotômetro e sua qualidade avaliada em eletroforese. Trinta e cinco amostras foram classificadas quanto ao seu grau de degradação, submetidas à extração de DNA e seu produto avaliado. A presença de material genético nas fezes frescas ou pouco degradadas apresentaram maiores concentrações de DNA além de melhor qualidade quando comparadas com as mais degradadas. Estes resultados evidenciam que, o DNA obtido empregando metodologia de baixo custo, possui quantidade e qualidade suficientes para seu em... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
12

Recolonization of the Midwestern United States by Large Carnivores: Habitat Suitability and Human Dimensions

Smith, Julia Blanche 01 May 2013 (has links)
Large carnivores in the United States are making a comeback following decades of systematic eradication. Black bears (Ursus americanus), cougars (Puma concolor), and gray wolves (Canis lupus) may recolonize the midwestern United States provided there is substantial suitable habitat. However, viability of large carnivore populations is as dependent on social acceptance as on biological factors. I developed individual and combined models of suitable habitat for black bears, cougars, and wolves in 18 midwestern states using geospatial data, expert-opinion surveys, and multi-criteria evaluation. I also assessed attitudes and perceptions of Illinois citizens about large carnivores via a mail-in survey. Experts indicated land cover was the most important variable for predicting potential habitat for black bears and cougars; human density was the most influential variable for wolves. Large, contiguous areas of suitable habitat comprised 35%, 21%, and 13% of the study region for wolves, bears, and cougars, respectively. About 12% of the region was considered suitable for all 3 species. Arkansas, Minnesota, Texas, and Wisconsin had the highest proportions (>40%) of suitable habitat for black bears; Arkansas, Michigan, Missouri, Texas, and Wisconsin had the most (≥20%) suitable cougar habitat; and only 4 states in the study region contained <29% suitable wolf habitat. Models were validated by comparing suitability values of independent sets of known carnivore locations to those of random locations, and models appeared accurate. More than 70% of survey respondents (n = 791) were male and their average age was 60; 55% were hunters. Approximately 40% were unsure about the population status of large carnivores in Illinois; of the remaining respondents, most (ranging from 20% for black bears to 41% for cougars) believed the presence of all 3 species had increased over the past decade. More residents supported protection (43%) and increasing numbers of large carnivores (39%) than opposed them (26%), although support for black bears was slightly higher than for cougars and wolves. Rural residents and livestock owners were the most likely to want carnivore numbers to decrease and least likely to support their protection; higher levels of education corresponded to positive attitudes toward large carnivores. My research provides the foundation for well-informed management plans, policy decisions, and educational initiatives for large carnivores in midwestern states where large carnivore populations have been absent for decades.
13

Cougar Predation and Ecological Energetics in Southern Utah

Ackerman, Bruce Bennet 01 May 1982 (has links)
Diet of cougars (Felis concolor) was studied from December 1978 to August 1981, on a 4500 km2 study area near Escalante, Utah. Prey eaten was determined from analysis of 112 animals consumed as prey, and from 239 cougar scats. Mule deer (Odocoileus hemionus) were the major prey item, comprising 81% of biomass consumed. Lagomorphs, large rodents, and smaller predators were also important components. Cattle comprised Motion-sensitive radio-transmitters were placed on 15 cougars, from 3 months to 7-9 years of age. Three parameters of the radio signal were used to determine activity levels during 6843 1-minute sampling periods: number of changes in pulse rate, predominant pulse mode, and signal integrity, based on 308 minutes of "known" acti vity. Cougars showed distinct crepuscular (sunrise, sunset ± 2 hrs) activity peaks (P Estimates of energetic costs of basal metabolism, and of activity, growth, and reproduction were used in a predictive model of energy cost of free-existence. Information on dietary composition, live weight and energy content of prey animals, and assimilation efficiencies were used to provide estimates of the frequency at which deer were killed (deer/day) and consumed (kg/day). Single adults were estimated to kill 1 deer per 8-16 days. Females with 3 large cubs would kill 1 deer as often as every 2-3 days. A known population of 8 adult cougars was predicted to consume 417 deer per year.
14

Ecology and Conservation of Cougars in the Eastern Great Basin: Effects of Urbanization, Habitat Fragmentation, and Exploitation

Stoner, David C. 01 May 2011 (has links)
This research was designed to investigate cougar response to urbanization, habitat fragmentation, and exploitation from behavioral, demographic, and landscape perspectives. The source-sink model has been proposed as an alternative framework for the management of exploited cougar populations. I addressed the basic question of whether cougars conform behaviorally to the predictions of the source-sink model, and consequently, the applied question of whether the model could be used for the conservation of this species. To achieve this I evaluated three scale-specific questions using radio-telemetry and hunter-harvest data collected from 1996-2010. At the subpopulation scale, I tested the hypothesis that cougars are wildland obligates by measuring cougar response to a suite of anthropogenic land uses. At the meso scale I compared cougar dispersal patterns from two populations under different management. Lastly, at the statewide scale I examined the distribution of human-induced de facto refugia and ecological traps in relation to the species range within Utah. Cougars show a strong proclivity for wildland over rural or suburban habitats, but all cougars used anthropogenic landscapes to some degree, and appear capable of surviving in highly disturbed, human-impacted environments. Cougar dispersal was correlated with maternal estrus; once young animals emigrated, natural and anthropogenic barriers directed movement into habitats marked by frequent human-caused mortality, with females selecting areas of lower conspecific density relative to males. Anthropogenic cougar mortality was disproportionately distributed in accessible, high quality habitats within the core of the species statewide range. Conversely, ecological traps were primarily situated within marginal habitats in remote settings on the periphery of the range. The source-sink model predicts that subordinate animals from saturated populations disperse to habitat with the highest suitability. Cougars of both sexes display behaviors that largely conform to these predictions. Based on the patchy but predictable distribution of cougar exploitation, Utah may already have a quasi source-sink system, which could be formalized through management action. In general, cougars are adaptable, behaviorally plastic, generalist carnivores, and as such defy broad habitat generalizations. These investigations have implications for sustainable hunting and long-term conservation of cougars in the multiple-use landscapes of the Intermountain West.
15

Cougar Exploitation Levels in Utah: Implications for Demographic Structure, Metapopulation Dynamics, and Population Recover

Stoner, David C. 01 May 2004 (has links)
Presently, eleven western states and two Canadian provinces utilize sport hunting as the primary mechanism for managing cougar (Puma concolor) populations. However, the impacts of sustained harvest on population dynamics and demographic structure arc not well understood. Additionally, the lack of cost-effective enumeration techniques and strongly conflicting societal values complicate effective management of this species. Given these concerns, the primary goals of this study were (I) to determine the effects of sustained harvest on cougar populations, and (2) estimate the level and extent of cougar harvest statewide. I monitored cougar populations on Monroe Mountain in south-central Utah, and in the Oquirrh Mountains of north-central Utah from 1999 to 2003. Over this interval the Monroe population was subjected to heavy annual removals and was characterized demographically by a younger age structure. low survival and fecundity, and declining density. In contrast , the Oquirrh Mountain population was partially protected and exhibited an older age distribution, relatively high survival and fecundity, and static density. To examine the statewide distribution of sport hunting, I mapped the locations of all cougars legally harvested from I 996-200 I, and calculated harvest rates by watershed (# cougars killed I yr I I 00 km2) . Population trends derived on the st udy sites under known harvest regimes were used as benchmarks and compared with rates calculated for occupied cougar habitat across the state. This provided an index of where cougar populations were stable or declining as a result of hunting pressure. Results from this research suggest heavy, sustained harvest can have significant impacts on cougar population dynamics and demographics. Patterns of recruitment resemble a source-sink population structure due in part to spatially variable management strategies. Moreover, these results indicate during the later I 990s, most of the statewide population was exploited at levels equal to or surpass ing those measured on Monroe Mountain. Because cougar density and habitat characteristics vary across management units, the temporal scale of population recovery will most likely depend on the interaction of harvest regime, productivity of unexploited populations, and landscape connectivity.
16

Cougar Predation Behavior in North-Central Utah

Mitchell, Dustin L. 01 May 2013 (has links)
Cougar (Puma concolor) predation has been identified as being one of several factors contributing to the decline of mule deer (Odocoileus hemionus) throughout the Western United States. In order to better understand how these elusive felines utilize their surroundings and prey, I examined and analyzed cougar predation behavior in North-Central Utah, using global positioning systems (GPS) data from 2002-2010. Twenty-three cougars were fitted with GPS collars and monitored for prey caching behavior. In total 775 potential cache sites were visited and 546 prey remains found. Mule deer comprised the majority of prey at cougar cache sites, but 11 other species were also found. Collectively, adult female mule deer were killed more than any other demographic class. Proportionally there was no difference in the sex or age class of deer killed by cougars in three different population segments, but seasonal differences were found in the number of kills made between cougar groups. Female cougars with kittens had a higher predation rate than males or solitary females, and seasonally more kills were made in the winter vs. summer. Cougars spent an average of 3.3 days on deer kills, and 6.2 days on elk kills. Habitat analyses suggested that cougars preferentially used Gambel oak (Quercus gambelii) over other land cover types when caching prey, as well as selected unburned over burned areas for caching and foraging on prey. These results suggest that cougars utilize dense stands of vegetation cover when stalking and concealing their prey. Wildlife managers may want to consider the use of prescribed burns in areas of high cougar predation on mule deer. This habitat manipulation tool could simultaneously help mule deer populations by reducing the percent of stalking cover afforded to cougars when attempting to kill prey, along with increasing nutrient levels of newly burned foliage and allow for an increased diversity in forb and shrub species available to mule deer.
17

Will we need to change the rules : assessing the implications of climate change for dam operations in Oregon's McKenzie River Basin

Danner, Allison G. 21 March 2013 (has links)
Dams and reservoirs are important components of water resource management systems, but their operational sensitivity to streamflow variability may make them vulnerable to climate change. Climate change is likely to affect the magnitude and timing of streamflow, motivating the assessment of potential impacts on dams and reservoirs. Here I examine a case study of Cougar Dam, a multipurpose dam in Oregon, USA, to assess potential impacts of future climate change on operational performance. In the first portion of this study, I examine the historical operation of Cougar Dam, to understand (1), whether operational objectives have been achievable in the past despite operational variability, and (2) how climatic variation is expressed in operational trajectories. By analyzing historical streamflow and operations data using a set of metrics, I characterize variability in past operations and how that variability relates to streamflow. I also employ a reservoir model to distinguish operational differences due to streamflow variability from variability due to other factors that affect operations. I find that operational objectives have been achievable, despite variability in operations and departures from the ideal operational trajectory. Throughout the historical period, flood control operations have almost always kept reservoir outflows below the desired maximum outflow. Although filling occurs 9 days late on average, the reservoir has filled in all but 6 out of 37 years. Although drawdown occurs 47 days early on average, early drawdown does not generally impact recreation and allows minimum outflows to be met every day during all but the driest year. I also find that total seasonal inflow is correlated with measures of operational performance, and that other factors besides climate play an important role in determining operational trajectories. I conclude that operations of Cougar Reservoir are vulnerable to climate change, but that operational flexibility may mitigate some of the potential impacts. In the second portion of this study I assume that current operating rules will be kept in place and I aim to understand what types of operational impacts may be expected, when they may be expected to occur, and whether the operational impacts may necessitate changing operational rules. I employ both a traditional climate impacts assessment approach to assess changes over time as well as a scenario-neutral approach to generalize relationships between streamflow and operations of Cougar Dam. I find that projected increases in winter streamflow could result in up to twice the number of downstream high flows than in the past and that projected decreases in summer streamflow could result in earlier reservoir drawdown by up to 20 days on average. Additionally, filling of the reservoir may occur up to 16% more often or 11% less often than in the past, depending on spring flow magnitude and timing. I also find that there are strong general relationships between total inflow volume and flood control performance, and that there are total inflow thresholds for whether or not the reservoir will fill or will be full enough for recreation in late summer. I conclude that future modification of operating policies may be warranted, but that there will likely be tradeoffs between operating objectives in the future even if operating rules are modified. / Graduation date: 2013
18

"Forty is the new twenty" : En analys av representationen av kvinnor i TV-serien Cougar Town

Öberg, Cecilia January 2011 (has links)
Populärkulturella fenomen når ut till ett stort antal människor och representationen av olikasaker blir således viktig eftersom det kan avspegla hur människor uppfattarolika ting. Syftet med min uppsats är att undersöka representationen av de trekvinnliga karaktärerna, Jules, Ellie och Laurie, i tv-serien Cougar Town. De teoretiska begreppsom står till grund för min analys är bland annat, representation somdefinieras i boken Genus, medier ochmasskultur skriven av Linda Fagerström och Maria Nilson och som AnjaHirdman också behandlar i sin avhandling Tilltalandebilder. Vidare har jag använt mig av begreppet postfeminism som både Karen Boyle (Massmedia and Society, 2005)och Karen Ross (Gendered Media, 2010) skriver om i sina böcker. För att undersökarepresentationen av de olika kvinnliga karaktärerna i tv-serien använder jagmig av Keith Selby och Ron Cowderys bok Howto study television. I deras bok finns olika steg att gå igenom för attkritiskt granska television, jag har vidare valt att fokusera på den narrativaoch konstruktionsanalysen med fokus på mise-enscène och den icke verbala kommunikationen samt klädkoderna. För att kunnainrikta mig på den narrativa analysen har jag även använt mig av annanlitteratur som jag tillämpat på min metod- och analysdel. Genom att kritisktgranska tv- serien Cougar Town tydliggörsvissa stereotypiska drag som återkommer under de två analyserade avsnitten (The Pilot) och (Feel a whole lot better). Jules och hennes två vänner kan vidförsta anblicken ses som exempel på postfeministiska karaktärer som är självsäkra och karriärsinriktade. Dock efter att ha studerat olika sekvenser på ett merdjupgående sätt framkommer många så kallade ”typiska kvinnliga drag” som populärkulturella fenomen ofta tenderar att visa.
19

Área de vida, padrões de deslocamento e seleção de habitat por Pumas (Puma concolor) e Jaguatiricas (Leopardus pardalis), em paisagem fragmentada do Estado de São Paulo / Home range, movement patterns and habitat selection by cougars (Puma concolor) and ocelot (Leopardus pardalis) in fragmented landscape in the State of Sao Paulo

Penteado, Marcel José Franco, 1977- 20 August 2018 (has links)
Orientadores: Eleonore Zulnara Freire Setz, José Eduardo Mantovani / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T00:59:02Z (GMT). No. of bitstreams: 1 Penteado_MarcelJoseFranco_D.pdf: 10454343 bytes, checksum: d8c60e67c27ebfc4bdb666229a8d4b1e (MD5) Previous issue date: 2012 / Resumo: O puma (Puma concolor) e a jaguatirica (Leopardus pardalis) são dois dos felídeos com maior distribuição geográfica no continente americano, ocorrendo em biomas que vão desde regiões muito secas até florestas tropicais. Assim como todos os predadores de porte médio e grande, necessitam de grandes áreas para sobreviver e são particularmente vulneráveis a extinções locais em ambientes fragmentados, onde seu desaparecimento pode levar a altas densidades de pequenos mamíferos predadores, ou mesopredadores, e ao empobrecimento dos níveis tróficos mais baixos. Além da perda de habitat, estas espécies sofrem com a falta de informações sobre sua ecologia, incluindo área de vida, uso de habitat e padrões de deslocamento e dispersão, essenciais para elaborar planos de manejo e estratégias de conservação eficientes. O presente trabalho analisou algumas destas informações em duas áreas com níveis significativos de impactos antrópicos (municípios de Paulínia, Cosmópolis, Americana e Atibaia), através do monitoramento de um puma por radiotelemetria GPS e três jaguatiricas por radiotelemetria VHF. Descrevemos a área de vida do puma com 11.400ha. Identificamos seleção para ambientes com cobertura vegetal arbórea e uso de matas ciliares como rotas de deslocamento. Também verificamos que seu nível de atividade decresce conforme a noite avança. Foi possível determinar locais prefereciais de predação através da análise de clusters, com indicações de que o puma monitorado identificou os melhores locais para predação de animais de maior porte. Também estimamos a área de vida para três jaguatiricas, variando entre 153 e 680ha, dentro do intervalo descrito para áreas de floresta tropical, mas muito inferior à descrita para outras áreas do continente americano, como o Pantanal e Iguaçú. Também verificamos preferência por ambientes com cobertura vegetal densa. Considerando os resultados obtidos, estratégias eficientes para a preservação destas espécies dependem da manutenção de áreas de mata nativa, interligadas por corredores de deslocamento, que permitam o trânsito destes animais entre eles e o contato e fluxo gênico entre populações distintas / Abstract: The cougar (Puma concolor) and the ocelot (Leopardus pardalis) are broadly distributed in the Americas, and occurs in biomes ranging from dry areas to tropical forests. As all medium to large sized predators, they need large landscapes to survive, and may be particularly vulnerable to local extinction in fragmented landscapes, where their disappearance can lead to higher densities of small mammalian predators, or mesopredators, and the impoverishment of lower trophic levels. Besides the loss of habitat, these species suffer from a lack of information about its ecology, including home range, habitat use and patterns of movement and dispersion, essential to develop effective management action plans and conservation strategies. The present study examined some of this information in two areas with significant levels of human impacts (municipalities in Paulínia, Cosmópolis, Americana and Atibaia), by monitoring a cougar by GPS radio telemetry and three ocelots by VHF radio telemetry. We describe the cougar's home range with 11.400ha (100% MCP). We found string selection for habitats with dense forest cover, and use of riparian areas as travel routes. We also found that their activity level decreases as the night progresses. We determinate preferecial predation sites by cluster analysis, with indications that the tracked cougar identified the best places to predation of larger animals. We also estimate the home range for three ocelots, ranging between 153 and 680ha (100% MCP) within the range reported for tropical forest, but much lower than that reported for other areas of the Americas, including brazilian Pantanal and Iguaçú. We also observed a preference for environments with dense vegetation. Considering these results, efficient strategies for the preservation of these species depend on maintaining areas of native forest, connected by movement corridors, allowing the transit of these animals between them and the contact and gene flow between different populations / Doutorado / Ecologia / Doutor em Ecologia
20

Cougar Resource Selection in Two Mountain Ranges in Utah: A Study on Scale and Behavior

Rieth, Wendy R. 01 May 2010 (has links)
An understanding of habitat relationships is essential for managing hunted species, such as cougar, that are difficult to census. In the first phase of this study, I used aerial telemetry data to examine diurnal cougar resource selection at 2 scales, and compared results between 2 study sites, the Oquirrh Mountains and Monroe Mountain, Utah. In the second phase of this study, I used conditional logistic regression models and GPS collar data from the Oquirrh Mountains to determine whether cougar resource selection varied over 3 behaviors (prey caching, resting at a daybed site, and nocturnal activities) and 2 scales. Results from phase 1 indicated that in general, during diurnal hours cougars selected for woodland cover types, moderate to steep (20-70%) slopes, canyon and steep hillside landforms, and home ranges with a higher density of edge. However, selection for these resources was not consistent at both study sites, scales, or for every cougar. Small sample sizes and poor spatial accuracy of the aerial telemetry data likely precluded the ability to detect selection in every case. Results from phase 2 indicated that cougar resource selection varied by behavior, and selection of some resources was detected only at certain scales. Cougar cache sites were characterized by southern and eastern aspects; lower elevation; avoidance of edge; a greater diversity of land cover types; canyon landforms (ridges were avoided); riparian, deciduous, and coniferous woodland; and deciduous and coniferous forest cover types. Cougars selected daybed sites that avoided western aspects and edges, were further from roads, closer to streams, higher in elevation, on moderate to steep slopes, and in rocky, deciduous woodland, and riparian cover types. During nocturnal activities, cougars avoided northern aspects, and selected areas that were closer to streams and roads, on edges and in canyon landforms, with gentler slopes, and rock, riparian, and deciduous woodland cover types. Results from cross-validation procedures confirmed that the models were reliable and predictive of cougar resource selection. This study provides a comprehensive analysis of cougar resource selection over various scales and behaviors. Managers should use caution when using diurnal data to make conclusions about selection during other times of day or behaviors.

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