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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.
31

An ecological study of waterfowl habitat at Powell's slough, Utah Lake

Barnett, Bruce I. 01 May 1967 (has links)
This study attempts to give a preliminary survey of the marsh habitat in Powell's Slough near Utah Lake. The following aspects are treated: seasonal waterfowl utilization of the slough, productivity of nesting water-fowl, description of the vegetation, invertebrate analysis, and analysis of environmental factors that may influence the habitat.
32

Benefits of the state acres for wildlife enhancement practice for bird populations in Kansas

Thomas, Alaina D. January 1900 (has links)
Master of Science / Division of Biology / Brett K. Sandercock / Grassland birds have experienced population declines worldwide from habitat degradation caused by conversion to agriculture and recent intensification of land use, including increased use of fertilizer, fossil fuels, and irrigation. The U.S. Department of Agriculture, Conservation Reserve Program (CRP) includes initiatives targeting wildlife enhancement to mitigate ongoing declines in grassland bird populations. The newest CRP practice, State Acres for Wildlife Enhancement (SAFE), was designed to restore vital habitats for high priority wildlife species throughout the United States. Our objective was to assess the potential benefits of SAFE for upland gamebirds and grassland songbirds in Kansas. We monitored lands enrolled in SAFE to estimate bird density based on field scale and landscape scale characteristics. Our study was conducted in three ecoregions: Smoky Hills (4 counties), Flint Hills (3 counties), and the High Plains (3 counties). We surveyed 121 SAFE fields and 49 CRP fields from 2012 – 2013. Northern Bobwhite density was negatively associated with percent litter within survey fields. Ring-necked Pheasant density differed among ecoregions, and was positively associated with percent bare ground in the High Plains, but negatively associated with field age in the Smoky Hills. Mourning Dove density differed among ecoregions, and was negatively associated with percent forb in the High Plains, and positively associated with percent grassland in the Smoky Hills. In the Flint Hills, Mourning Doves were negatively associated with CRP fields and large fields. Brown-headed Cowbirds were positively associated with percent forbs. Amount of CRP surrounding survey locations was positively associated with bird density through the entire range for Grasshopper Sparrows, Dickcissels, and Lark Buntings, and in the High Plains for Western Meadowlarks. Percent woodland had negative effects on Western Meadowlarks in the Smoky Hills, whereas percent cropland had negative effects on Eastern Meadowlarks statewide. CRP positively affected abundance of four of our species, whereas percent cropland and woodland negatively affected others. Thus, the amount of set-aside lands enrolled in SAFE could be important for grassland bird populations. SAFE and CRP supported equal numbers of Northern Bobwhites and Ring-necked Pheasants, suggesting SAFE provides benefits for target species of upland gamebirds.
33

Taxonomia e distribuição geográfica do complexo Penelope superciliaris Temminck, 1815 (Aves: Galliformes: Cracidae) / Taxonomy and geographic distribution of Penelope superciliaris complex Temminck, 1815 (Aves: Galliformes: Cracidae)

Vargas, Oscar Diego Evangelista 09 May 2017 (has links)
Penelope superciliaris Temminck, 1815, comumente conhecido como jacupemba, é o jacu com a mais ampla área de distribuição, ocorrendo no Brasil, Paraguai, Argentina e Bolívia, sendo também uma das sete espécies do gênero Penelope distribuída no Brasil. Suas subespécies foram descritas com base na largura e a tonalidade das bordas das penas, no desenvolvimento da linha superciliar, pigmentação das partes nuas, coloração geral da plumagem e tamanho. A taxonomia deste táxon é complexa e até hoje muitos autores nunca chegaram a um consenso sobre a validade dos táxons subordinados, a maioria deles reconhece apenas três subespécies: P. s. superciliaris, P. s. jacupemba e P. s. major, outras populações propostas como novas subespécies geográficas são atualmente sinonimizadas com as três anteriores. Para este complexo nenhuma revisão foi realizada nos últimos 70 anos, é por isso que, com coletas recentes de material novo, estamos realizando uma revisão taxonômica com base em caráteres morfológicos externos. O objetivo deste trabalho é verificar quantos táxons estão no nível de espécie no complexo Penelope superciliaris e delimitar suas respectivas distribuições geográficas, de acordo com o bioma em que eles ocorrem. Para atingir esses objetivos, realizamos análises qualitativas de carácteres morfológicos externos como coloração da plumagem, pigmentação das partes nuas, e também foram testadas variações inter- e intra-populacionais de acordo com esses caráteres. Para a análise estatística foram realizados testes univariados e multivariados para avaliar o dimorfismo sexual e a variação geográfica. De dezoito grupos geográficos formados, as análises qualitativas revelam que não há dimorfismo sexual, e a maioria delas tem um alto grau de variação individual. As análises estatísticas não discriminaram os sexos e populações com base nas oito medidas corporais utilizadas, porém os táxons foram discriminados pela coloração da plumagem e a pigmentação das regiões nuas. De acordo com o Conceito Filogenético de Espécies (PSC), consideramos que o complexo Penelope superciliaris deve ser dividido em quatro espécies: Penelope pseudonyma Neumann, 1933, uma população de jacus de cara azul restrita ao interflúvio Madeira-Tapajós na floresta amazônica; Penelope ochromitra Neumann, 1933, da Caatinga e Cerrado que limita com este bioma; Penelope alagoensis Nardelli, 1993, do Centro de Endemismo Pernambuco; e Penelope superciliaris Temminck, 1815, que ocorre no resto da distribuição do complexo. / Penelope superciliaris Temminck, 1815, known as Rusty-margined Guan, is a forest guan with the widest distribution, occurring in Brazil, Paraguay, Argentina and Bolivia, being also one of the seven species of the genus Penelope distributed in Brazil. Its subspecies have been described based on the width and shade of edges of feathers, the development of the superciliary stripe, naked parts pigmentation, general plumage coloration and size. The taxonomy of this taxon is complex and even today many authors never reached a consensus on the validity of the subordinate taxa; most of them recognize only three subspecies: P. s. superciliaris, P. s. jacupemba and P. s. major; other populations proposed as new races are currently synonymized with the previous three. For this complex, no review was conducted in the last 70 years that is why, with recent collection of new material, I performed a taxonomic revision based on external morphological characters. The aim on this work is to verify how many taxa exist at the species level in the Penelope superciliaris complex, and delimit their respective geographic distributions. To achieve these goals, we performed qualitative analyzes of external morphological characters as plumage coloration, naked parts pigmentation, and were tested inter- and intra-populational variations according to these characters. For statistical analyzes we performed univariate and multivariate tests to evaluate the sexual dimorphism and geographical variation. From eighteen geographic groups formed, the qualitative analyzes reveals that there is no sexual dimorphism, and most of them have a high degree of individual variation. Statistical analyzes did not discriminate the sexes and populations based on the eight body measurements used, but the taxa were discriminated by plumage coloration and naked parts pigmentation. According to the Phylogenetic Species Concept (PSC), we consider that the Penelope superciliaris complex must be divided in four species: Penelope pseudonyma Neumann, 1933, a blue-faced guans population restricted to the Madeira-Tapajós interfluvium in the Amazon forest; Penelope ochromitra Neumann, 1933, from the Caatinga and Cerrado that borders with this biome; Penelope alagoensis Nardelli, 1993, from the Pernambuco Center of Endemism; and Penelope superciliaris Temminck, 1815, which occurs in the rest of the distribution of the complex.
34

Taxonomia e distribuição geográfica do complexo Penelope superciliaris Temminck, 1815 (Aves: Galliformes: Cracidae) / Taxonomy and geographic distribution of Penelope superciliaris complex Temminck, 1815 (Aves: Galliformes: Cracidae)

Oscar Diego Evangelista Vargas 09 May 2017 (has links)
Penelope superciliaris Temminck, 1815, comumente conhecido como jacupemba, é o jacu com a mais ampla área de distribuição, ocorrendo no Brasil, Paraguai, Argentina e Bolívia, sendo também uma das sete espécies do gênero Penelope distribuída no Brasil. Suas subespécies foram descritas com base na largura e a tonalidade das bordas das penas, no desenvolvimento da linha superciliar, pigmentação das partes nuas, coloração geral da plumagem e tamanho. A taxonomia deste táxon é complexa e até hoje muitos autores nunca chegaram a um consenso sobre a validade dos táxons subordinados, a maioria deles reconhece apenas três subespécies: P. s. superciliaris, P. s. jacupemba e P. s. major, outras populações propostas como novas subespécies geográficas são atualmente sinonimizadas com as três anteriores. Para este complexo nenhuma revisão foi realizada nos últimos 70 anos, é por isso que, com coletas recentes de material novo, estamos realizando uma revisão taxonômica com base em caráteres morfológicos externos. O objetivo deste trabalho é verificar quantos táxons estão no nível de espécie no complexo Penelope superciliaris e delimitar suas respectivas distribuições geográficas, de acordo com o bioma em que eles ocorrem. Para atingir esses objetivos, realizamos análises qualitativas de carácteres morfológicos externos como coloração da plumagem, pigmentação das partes nuas, e também foram testadas variações inter- e intra-populacionais de acordo com esses caráteres. Para a análise estatística foram realizados testes univariados e multivariados para avaliar o dimorfismo sexual e a variação geográfica. De dezoito grupos geográficos formados, as análises qualitativas revelam que não há dimorfismo sexual, e a maioria delas tem um alto grau de variação individual. As análises estatísticas não discriminaram os sexos e populações com base nas oito medidas corporais utilizadas, porém os táxons foram discriminados pela coloração da plumagem e a pigmentação das regiões nuas. De acordo com o Conceito Filogenético de Espécies (PSC), consideramos que o complexo Penelope superciliaris deve ser dividido em quatro espécies: Penelope pseudonyma Neumann, 1933, uma população de jacus de cara azul restrita ao interflúvio Madeira-Tapajós na floresta amazônica; Penelope ochromitra Neumann, 1933, da Caatinga e Cerrado que limita com este bioma; Penelope alagoensis Nardelli, 1993, do Centro de Endemismo Pernambuco; e Penelope superciliaris Temminck, 1815, que ocorre no resto da distribuição do complexo. / Penelope superciliaris Temminck, 1815, known as Rusty-margined Guan, is a forest guan with the widest distribution, occurring in Brazil, Paraguay, Argentina and Bolivia, being also one of the seven species of the genus Penelope distributed in Brazil. Its subspecies have been described based on the width and shade of edges of feathers, the development of the superciliary stripe, naked parts pigmentation, general plumage coloration and size. The taxonomy of this taxon is complex and even today many authors never reached a consensus on the validity of the subordinate taxa; most of them recognize only three subspecies: P. s. superciliaris, P. s. jacupemba and P. s. major; other populations proposed as new races are currently synonymized with the previous three. For this complex, no review was conducted in the last 70 years that is why, with recent collection of new material, I performed a taxonomic revision based on external morphological characters. The aim on this work is to verify how many taxa exist at the species level in the Penelope superciliaris complex, and delimit their respective geographic distributions. To achieve these goals, we performed qualitative analyzes of external morphological characters as plumage coloration, naked parts pigmentation, and were tested inter- and intra-populational variations according to these characters. For statistical analyzes we performed univariate and multivariate tests to evaluate the sexual dimorphism and geographical variation. From eighteen geographic groups formed, the qualitative analyzes reveals that there is no sexual dimorphism, and most of them have a high degree of individual variation. Statistical analyzes did not discriminate the sexes and populations based on the eight body measurements used, but the taxa were discriminated by plumage coloration and naked parts pigmentation. According to the Phylogenetic Species Concept (PSC), we consider that the Penelope superciliaris complex must be divided in four species: Penelope pseudonyma Neumann, 1933, a blue-faced guans population restricted to the Madeira-Tapajós interfluvium in the Amazon forest; Penelope ochromitra Neumann, 1933, from the Caatinga and Cerrado that borders with this biome; Penelope alagoensis Nardelli, 1993, from the Pernambuco Center of Endemism; and Penelope superciliaris Temminck, 1815, which occurs in the rest of the distribution of the complex.
35

A comparative study of avian oviducal sperm storage with special reference to factors which regulate sperm motility /

Holm, Lena, January 1900 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.
36

Game meat production in the Xhariep district of the Free State province : evaluating and optimising resources

Derbyshire, Walter January 2011 (has links)
Thesis (D. Tech. Environmental health) -- Central University of technology, Free State, 2011 / In addition to one national park and six nature reserves, the Free State Province boasts several privately owned game reserves, as well as game farmers and commercial stock farmers who keep game. A survey conducted in 1985 showed that the majority of game could be found in the Xhariep District situated in the southern and south-western parts of the province. Game export abattoirs and processing facilities are situated in provinces other than the Free State, which results not only in an outflow of game carcasses for export purposes, but also a loss of employment opportunities and opportunities for the generation of foreign currency from a district (Xhariep) which, from a socio-economic perspective, is seen as deprived. There are 21 non-export highthroughput red meat abattoirs in the province, posing the question as to whether these could be used for the slaughtering of game. This study aimed firstly to compile guidelines for the wild game meat industry regarding the production of wild game meat for the international market and to assess wild game production and utilisation in the Xhariep District through a comprehensive survey of game farming practices, game numbers and species, as well as the utilisation of game through various consumptive and non-consumptive methods. A further aim was to investigate practices at existing slaughter facilities in order to determine their potential to be adapted into wild game meat export facilities and assess such potential via a standardised protocol. The research commenced with an investigation into processing and export requirements for wild game meat in South Africa through a literature study of all EU legislation, directives and other relevant literature on the subject, and provides comprehensive reference material for entrepreneurs and developers in the wild game meat industry. Methodologies utilised included audits to determine the extent to which abattoirs conform to the structural, operational and documentation meat hygiene requirements followed by the development of a novel assessment matrix for measuring the level of compliance of existing abattoirs and their potential to be developed into European Union (EU) export facilities. The survey of the Xhariep area concluded that a significant potential exists for the expansion of the game industry, as several respondents indicated that they were interested in expanding their game production and that they had land available for this purpose. A further indication was that the game would be highly marketable because it was free ranging and could be regarded as organic due to the absence or controlled use of additives and pesticides that could result in chemical residues in the meat. The establishment of a wild game export facility was favoured by nearly 70% of the respondents. The hygiene evaluation of existing slaughter facilities in the Free State Province resulted in six slaughtering facilities being rated as good or excellent, demonstrating the potential to successfully process game meat for the export market. This was tested by utilising the proposed evaluation matrix, which rated the abattoirs most suited to be adapted into game meat processing facilities for export purposes. The value of this approach lies in the fact that it is not only restricted to local markets, but can be utilised internationally by the abattoir industry, as well as the fact that it is not species specific. It should, however, be applied objectively by knowledgeable operators in the industry. It is concluded that institutions in the Free State Province possess the knowledge and ability to not only produce wild game meat, but also to successfully process this commodity through the optimal utilisation of existing high-throughput red meat abattoirs. By utilising existing management skills and affecting relatively minimal adjustments to existing structures, these resources should be utilised to successfully enter the wild game meat export market which should, in turn contribute towards the prosperity of the Xhariep District.
37

Using nutritional quality of forage and faeces for predicting sustainable livestock and game stocking rates at Pniel Estates in Northern Cape, South Africa

Mbatha, Khanyisile R. 03 1900 (has links)
Thesis (PhD)--University of Stellenbosch, 2010. / The aim of the study was to assess the importance of spatial and temporal variation in diet quality and abundance for determining sustainable stocking rates on commercial, communal and game ranches in a semi-arid savanna, with the ultimate goal of avoiding land degradation in the long term, to provide sustainable livelihoods in rangelands and to make policy that will help in managing the available natural resources in the rangelands. Thus, firstly the effects of grazing, fire, nitrogen and water availability on nutritional quality of grass in semi-arid savanna was assessed. Secondly, spatial and temporal variation in plant quantity and quality among management (commercial, communal and game) types and habitat types (open savanna, rocky, shrubby and pans) and stocking rates in different management types were determined. Thirdly, the quality and quantity of variation inside and outside herbivore exclosures among commercial, communal and game management and habitat types in the semi arid savanna were estimated. Fourthly, faecal profiling was used to assess the effects of different management types on diet quality in semi-arid savanna. Lastly, policy based on the results of the present study was formulated.

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