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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.
291

L'influence de l'anthropisation sur la répartition géographique du condor des Andes (Vultur gryphus L.) dans le Parc National Torres del Paine en Patagonie chilienne

Costina, Mircea Ioan January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
292

Bayesian multi-species modelling of non-negative continuous ecological data with a discrete mass at zero

Swallow, Ben January 2015 (has links)
Severe declines in the number of some songbirds over the last 40 years have caused heated debate amongst interested parties. Many factors have been suggested as possible causes for these declines, including an increase in the abundance and distribution of an avian predator, the Eurasian sparrowhawk Accipiter nisus. To test for evidence for a predator effect on the abundance of its prey, we analyse data on 10 species visiting garden bird feeding stations monitored by the British Trust for Ornithology in relation to the abundance of sparrowhawks. We apply Bayesian hierarchical models to data relating to averaged maximum weekly counts from a garden bird monitoring survey. These data are essentially continuous, bounded below by zero, but for many species show a marked spike at zero that many standard distributions would not be able to account for. We use the Tweedie distributions, which for certain areas of parameter space relate to continuous nonnegative distributions with a discrete probability mass at zero, and are hence able to deal with the shape of the empirical distributions of the data. The methods developed in this thesis begin by modelling single prey species independently with an avian predator as a covariate, using MCMC methods to explore parameter and model spaces. This model is then extended to a multiple-prey species model, testing for interactions between species as well as synchrony in their response to environmental factors and unobserved variation. Finally we use a relatively new methodological framework, namely the SPDE approach in the INLA framework, to fit a multi-species spatio-temporal model to the ecological data. The results from the analyses are consistent with the hypothesis that sparrowhawks are suppressing the numbers of some species of birds visiting garden feeding stations. Only the species most susceptible to sparrowhawk predation seem to be affected.
293

Composição da avifauna, frugivoria e dispersão de sementes por aves em áreas de floresta estacional semidecidual e cerrado, no Parque Estadual de Porto ferreira, São Paulo / Avifauna, frugivory and seed dispersal by birds in areas of semideciduous forest and savanna in the Porto ferreira state park, Sao Paulo

Athiê, Samira 29 October 2014 (has links)
Made available in DSpace on 2016-06-02T19:30:09Z (GMT). No. of bitstreams: 1 6453.pdf: 5537867 bytes, checksum: 57a708de759300745321cdff506b4e17 (MD5) Previous issue date: 2014-10-29 / Financiadora de Estudos e Projetos / In the São Paulo State predominated two large phytoecological formations: the semideciduous forests and the savanna. The extensive use of these areas mainly for cane sugar plantations and other monocultures, caused a high loss of habitats. While still play an important role in maintaining the biodiversity of the State, there is a lack of information on bird communities in this region. In this sense, we have developed a comprehensive study on the avifauna of Porto Ferreira State Park (PFSP), which protects one of the few stretches of ecological tension between semideciduous forest and savanna in São Paulo. In Chapter I, we analyze the composition and structure of PFSP‟s bird community. We recorded 207 bird species in the area, between February 2011 and October 2013, including 15 threatened/near threatened species, 22 endemic to the Atlantic Forest and two endemic to savanna. We found that the PFSP has a bird richness similar to large fragments of the region, although the most sensitive species and more demanding in the resources exploitation are less abundant compared to generalist species and to the most conserved fragments of the surroundings. In Chap. II, we evaluated the interaction between frugivorous birds and PFSP‟s ornithochoric plants. There was availability of attractive fruit throughout the year, with peak productivity between September and October, in line with the pre-reproductive period of birds and the arrival of migratory species. Despite the prevalence of generalist birds that disperse mainly small seeds of plants from the early succession stages, we found the PFSP has a diversified frugivorous bird-plant interaction network compared to other forest fragments of the State, due to the variety of available environments, connection with other surroundings fragments and its medium size and rounded shape, softening the matrix impact. In Chap. III, we evaluated the potential of bird perches in increasing the seed rain in an abandoned pasture within the PFSP limits. Therefore, we installed seed traps under natural perches (living trees) and artificial, noting the number of deposited seeds increased proportionally to the amount of landing perches structures. Natural perches also provided other resources for birds, such as fruits, insects and shelter, making them more attractive. We conclude that natural perches and artificial perches with more elaborate architecture showed greater efficiency in attracting seed-disperser birds and increasing the seed deposition, being the most recommended for this area recovery and for ecological restoration projects. / No interior do Estado de São Paulo predominavam duas grandes formações fitoecológicas: as Florestas Estacionais e o Cerrado. O uso extensivo dessas áreas principalmente para plantações de cana-de-açúcar e outras monoculturas, ocasionou uma elevada perda de habitats. Embora ainda desempenhe um importante papel na manutenção da biodiversidade do Estado, há carência de informações sobre a comunidades de aves dessa região. Neste sentido, desenvolvemos um estudo amplo sobre a avifauna do Parque Estadual de Porto Ferreira (PEPF), que protege um dos poucos trechos de tensão ecológica entre Floresta Estacional Semidecidual e Cerrado do interior paulista. No Capítulo I, analisamos a composição e a estrutura da comunidade de aves do PEPF. Registramos 207 espécies de aves na área, entre fevereiro de 2011 e outubro de 2013, incluindo 15 ameaçadas/quase ameaçadas de extinção, 22 endêmicas de Mata Atlântica e duas endêmicas de Cerrado. Verificamos que o PEPF apresenta riqueza avifaunística similar aos grandes fragmentos da região, embora as espécies mais sensíveis e mais exigentes na exploração de recursos sejam pouco abundantes quando comparadas às espécies generalistas e em relação aos fragmentos mais conservados do entorno. No Cap. II, avaliamos a interação entre as aves frugívoras e as plantas ornitocóricas do PEPF. Houve disponibilidade de frutos atrativos ao longo de todo o ano, com pico de produtividade entre setembro e outubro, em consonância com o período pré-reprodutivo das aves e com a chegada de espécies migratórias. Embora predominem as aves generalistas que dispersam principalmente pequenas sementes de plantas de estágios iniciais da sucessão, constatamos que o PEPF apresenta uma rede de interações ave frugívora-planta bastante diversificada em comparação com outros fragmentos florestais do Estado, em função da variedade de ambientes disponíveis, da conexão com outros fragmentos do entorno e do seu tamanho médio e formato arredondado, amenizando os impactos da matriz. No Cap. III, avaliamos o potencial de poleiros para aves no incremento da chuva de sementes em um antigo pasto abandonado, dentro dos limites do PEPF. Para tanto, instalamos coletores de sementes sob poleiros naturais (árvores vivas) e artificiais, constatando que o número de sementes depositadas aumentou proporcionalmente à quantidade de estruturas de pouso dos poleiros. Os poleiros naturais também disponibilizaram outros recursos para a avifauna, como frutos, insetos e abrigo, tornando-os mais atrativos. Concluímos que os poleiros naturais e os poleiros artificiais com arquitetura mais elaborada demonstraram maior eficiência na atração das aves dispersoras e no incremento da deposição de sementes, sendo os mais recomendados para a recuperação daquela área e para projetos de restauração ecológica.
294

Knowledge and practice of live bird sellers on health risks and preventive measure of Avian Influenza in an urban community of Lagos state, Nigeria

Ilonze, Chinyere Charity January 2010 (has links)
Magister Public Health - MPH / Avian Influenza (AI) is a contagious viral zoonotic disease with great public health implications and negative socioeconomic impact (WHO, 2006a). The highly pathogenic avian influenza (HPAI) infection is transmitted from birds to man mostly through contact with contaminated poultry and objects (INFOSAN, 2005), hence people who come in contact with birds such as live bird sellers (LBS) are the more vulnerable population (WHO, 2006a). Inadequate knowledge of AI health risks and poor practice of AI preventive measures amongst LBS increases the risk of spread of the infection in both humans and animals.The aim of this study was to describe and quantify the knowledge and practice of LBS with regards to avian influenza health risks and preventive activities in Agege, an urban area in Lagos State, Nigeria. / South Africa
295

The ecology and conservation of the white-winged nightjar Caprimulgus candicans

Pople, Robert Grant January 2003 (has links)
In the tradition of previous studies of threatened species, this thesis was undertaken with the aim of improving our understanding of the ecology of the White-winged Nightjar Caprimulgus candicans, and providing the information necessary to facilitate conservation efforts on its behalf. In 1998-2001, I studied a population of White-winged Nightjars at Aguará Ñu, an area of cerrado habitats within the Reserva Natural del Bosque Mbaracayù, eastern Paraguay. Over the course of three fieldwork seasons, I captured and ringed a total of 49 nightjars (34 adults and 15 young birds). Young females first bred at approximately one year old, while still in pre-definitive plumage. Young males exhibited a form of delayed plumage maturation, whereby they only attained definitive plumage following a prolonged moult spanning much of their first potential breeding season. No evidence was obtained to suggest that they succeeded in breeding while in this conspicuously intermediate state of moult. Considerable variation was noted in the plumage whiteness of definitive males, but no clear evidence was found for consistent age-related increases in white. During the breeding season, males defended small aggregated display territories, at which they conducted nuptial display flights between late August and early January. Female nightjars were responsible for all the parental care, and apparently visited male display arenas solely to obtain copulations. Chick paternity data confirmed that the study population was polygynous, with patterns of male aggregation suggestive of an exploded lek or 'landmark' mating system. Radio-telemetry studies showed that nightjars utilised home ranges of at least 20 to 40 hectares during the eight to ten months for which they were monitored. Home ranges contained a disproportionately large amount of young campo cerrado vegetation, but no forest or old campo cerrado habitats. When selecting foraging sites within their ranges, nightjars preferred younger and avoided older campo cerrado vegetation; wet grassland was utilised roughly in proportion to its availability. Observed patterns of habitat selection were potentially explained by the greater abundance of insect prey in younger habitats. When selecting daytime roost sites, nightjars preferred vegetation of intermediate age, reflecting their need for a balance between cover and ease of access. A more general analysis of patterns of sexual dimorphism within the Caprimulgidae showed that, although almost 80% of nightjar species exhibit some dimorphism of plumage whiteness, the study species was by far the most extreme case. The striking plumage of the male was partly explained by a strong positive relationship between wing white and openness of breeding habitats within the family. However, this failed to explain the complete absence of white in the female plumage, or the extent of white dimorphism shown by the species. The most likely explanation would appear to be that extreme plumage dimorphism occurred in conjunction with the evolution of polygyny and female-only care in this open-country species. The implications of these findings for the conservation of the White-winged Nightjar are highlighted, and recommendations are proposed for future work and conservation action.
296

A Comparison of Image Processing Techniques for Bird Detection

Reyes, Elsa 01 June 2014 (has links)
Orchard fruits and vegetable crops are vulnerable to wild birds and animals. These wild birds and animals can cause critical damage to the produce. Traditional methods of scaring away birds such as scarecrows are not long-term solutions but short-term solutions. This is a huge problem especially near areas like San Luis Obispo where there are vineyards. Bird damage can be as high as 50% for grapes being grown in vineyards. The total estimated revenue lost annually in the 10 counties in California due to bird and rodent damage to 22 selected crops ranged from $168 million to $504 million (in 2009 dollars). A more effective and permanent system needs to be put into place. Monitoring systems in agricultural settings could potentially provide a lot of data for image processing. Most current monitoring systems however don’t focus on image processing but instead really heavily on sensors. Just having sensors for certain systems work, but for birds, monitoring it is not an option because they are not domesticated like pigs, cows etc. in which most these agricultural monitoring systems work on. Birds can fly in and out of the area whereas domesticated animals can be confined to certain physical regions. The most crucial step in a smart scarecrow system would be how a threat would v be detected. Image processing methods can be effectively applied to detecting items in video footage. This paper will focus on bird detection and will analyze motion detection with image subtraction, bird detection with template matching, and bird detection with the Viola-Jones Algorithm. Of the methods considered, bird detection with the Viola-Jones Algorithm had the highest accuracy (87%) with a somewhat low false positive rate. This image processing step would ideally be incorporated with hardware (such as a microcontroller or FPGA, sensors, a camera etc.) to form a smart scarecrow system.
297

The Influence of Japanese Composers on the Development of the Repertoire for the Saxophone and the Significance of the Fuzzy Bird Sonata by Takashi Yoshimatsu

Hanafusa, Chiaki 05 1900 (has links)
The history of the saxophone and its development as a performance medium in Japan is short when compared with other European countries and the United States. In this short history, the saxophone performance level in Japan has increased dramatically. At the same time, compositions for the saxophone by Japanese composers have gained more popularity in the world as can be seen in the program of the World Saxophone Congress and the North American Saxophone Alliance conference. The saxophone history in Japan, including contributions of Arata Sakaguchi (1910-1997), Ryo Noda (b.1948), and Nobuya Sugawa (b.1961), is discussed in order to understand the increase of performances of pieces for saxophone by Japanese composers. The success of many original compositions, especially those that incorporate the synthesis of Eastern and Western music, is another significant element examined in this document. Yoshimatsu approaches music for classical saxophone as a new genre. He seeks all possible sounds that the saxophone can create - beautiful tone to "noise like" - in his compositions. The blending of other musical styles in one piece is one of Yoshimatsu's compositional styles, which can be observed in Fuzzy Bird Sonata; however, he does not limit himself to a single style. This unique style with some technical challenges attracts saxophonists and audiences. An analysis of Fuzzy Bird Sonata is provided in order to have a better understanding of the piece and to address performance practice issues. Also various interpretations are examined by comparing available recordings of Sugawa, Nicolas Prost, and Rob Buckland.
298

[en] OUT OF THE SHADOW: THE BRAZILIAN SOCIAL MOVEMENT IN THE LOAN BY THE WORLD BANK TO THE BRAZILIAN NATIONAL AIDS PROGRAM / [pt] SAINDO DA SOMBRA: O MOVIMENTO SOCIAL BRASILEIRO NO FINANCIAMENTO DOBANCO MUNDIAL AOPROGRAMA NACIONAL DE AIDS

EZIO TAVORA DOS SANTOS FILHO 16 August 2002 (has links)
[pt] Dissertação de Mestrado que avalia o impacto da participação do movimento social brasileiro em aids na negociação entre o Governo Brasileiro, representado pelo Programa Nacional de DST /Aids, do Ministério da Saúde, e o Banco Internacional para a Reconstrução e o Desenvolvimento, BIRD, ou Banco Mundial. Discorre sobre as várias abordagens acerca de movimento social, assim como acerca da relevância do tema pandemia de aids para as Relações Internacionais,considerando os impactos econômicos, populacionais e de segurança nacional da epidemia mundial de HIV e aids. A dissertação se baseia em bibliografia primária e secundária,incluindo dissertações e teses, bem como documentos originais, assim como em entrevistas com as pessoas que desempenharam funções importantes na negociação do chamado AIDS I, qual seja o primeiro Acordo de Empréstimo entre o BIRD e o Programa Nacional de Aids, negociação essa que se deu entre os anos de 1992 e 1994. / [en] This Masters dissertation analyses the impact of the participation of the Brazilian social movement on AIDS in the negotiation between the Brazilian Government, represented by the National STD/AIDS Program by the Brazilian Ministry of Health,and the International Bank for Reconstruction and Development, IBRD, or the World Bank. It discourses upon different approaches to the social movement, and stresses the relevance of the AIDS pandemic to the International Relations, regarding diverse aspects on economy, population, and national security. The dissertation is based on primary and secondary bibliography, including dissertations and thesis; on original documents, as well as on interviews to key individuals who were involved, between 1992 e 1994, in the negotiation of the so called AIDS I, first Loan Agreement between the IBRD and the National Program on AIDS.
299

Mexican Macaws: Comparative Osteology and Survey of Remains from the Southwest

Hargrave, Lyndon L. January 1970 (has links)
"Macaws is a field and laboratory guide to the identification of the Military Macaw and the Scarlet Macaw. Also included is a survey of all the Southwestern culture areas which have produced macaw remains...A "labor of love" by the author...Scholarly addition to our knowledge of Southwestern prehistory." --Southwestern Lore "Excellent monograph, well illustrated...Much useful and interesting data in this study."--American Antiquity
300

Modelling of a thermodynamically driven heat engine with application intended for water pumping

Craig, Rob James 12 1900 (has links)
Thesis (MEng) -- Stellenbosch University, 2014. / ENGLISH ABSTRACT: See PDF for abstract. / AFRIKKANSE OPSOMMING: Sien PDF vir die opsomming.

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