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Composição e dinâmica da comunidade de aves em fragmento de mata atlântica no extremo norte do Rio Grande do SulSantos, Marcelo Fischer Barcellos dos 27 February 2009 (has links)
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Previous issue date: 27 / Universidade do Vale do Rio dos Sinos,Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente trabalho teve como objetivos caracterizar a estrutura, composição e dinâmica da comunidade de aves em um fragmento de Mata Atlântica localizado no extremo norte do estado do Rio Grande do Sul, bem como realizar análises comparativas entre interior e borda de floresta em relação a (1) composição de espécies, (2) riqueza, (3) abundância de grupos funcionais de aves e (4) abundância de espécies endêmicas de Mata Atlântica. Foram definidos 22 grupos funcionais de aves para descrição geral do fragmento de floresta estudado e comparação entre interior e borda de floresta, entretanto apenas 11 puderam ser comparados a nível estatístico, os demais grupos não obtiveram suficiência amostral para serem incluídos nas análises. Os grupos funcionais utilizados na comparação de abundância entre borda e interior de floresta foram: granívoros/insetívoros generalistas, granívoros/frugívoros de solo, insetívoros de sub-bosque, insetívoros de sub-bosque e estrato médio, insetívoros escaladores de troncos e galhos, ins / The present goal was to characterize structure, composition and dynamics of bird community at an Atlantic Forest remnant at the extreme north of Rio Grande do Sul State as well to compare interior and forest edge related to (1) species composition, (2) richness, (3) abundance of functional groups and (4) Atlantic Forest abundance of endemics bird species. General description of the fragment and comparisons between forest interior and edge were based on 22 defined functional groups, however only 11 could be compared to statistical level, the other groups did not obtain sufficient sample data to be included in the analysis. Functional groups used in the comparison between the abundance of forest edge and interior were: generalist seedeater/insectivores, ground seedeater/frugivores, understory insectivores, mid and understory insectivores, tunk and twig insectivores, bamboo or forest tangle insectivores, canopy insectivores, mid and understory insectivore/frugivores, canopy insectivore/frugivores, nectarivore/in
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Novas informações sobre a história natural da maria-da-restinga (Phylloscartes kronei) (Aves, Tyrannidae) /Gussoni, Carlos Otávio Araújo. January 2010 (has links)
Orientador: Marcos César de Oliveira Santos / Banca: Marco Aurelio Pizo Ferreira / Banca: Pedro Ferreira Develey / Resumo: A maria-da-restinga (Phylloscartes kronei) é uma espécie da família Tyrannidae descrita recentemente e considerada como globalmente ameaçada de extinção, cuja história natural é pouco conhecida. Visando preencher parte desta lacuna, o objetivo deste estudo foi de caracterizar o comportamento de forrageamento da maria-da-restinga, descrever os bandos mistos aos quais ela se associa, bem como descrever alguns outros aspectos de sua história natural como seus hábitos alimentares, o comportamento de dormir, insights sobre a biologia reprodutiva, o alcance de vôo, encontros agonísticos interespecíficos e a muda. No período de agosto de 2008 a julho de 2009 foram realizadas excursões mensais ao município de Ilha Comprida (~24º S), Estado de São Paulo. Aliado ao esforço anual mencionado, uma visita ao município de Guaraqueçaba (25º18'S e 48º19'W), Estado do Paraná, foi conduzida entre os dias 25 de julho e 1º de agosto de 2008. Foram coletadas 613 amostras de forrageamento, através de observações diretas com auxílio de binóculos com aumento de 10 vezes. Durante os períodos de coleta de dados sobre o forrageamento da espécie, para cada encontro com a mesma foi anotado se esta se encontrava só, aos pares, em grupos ou associada a bandos mistos de aves. Quando em bandos mistos, foram anotadas todas as espécies ocorrentes, visando caracterizar os bandos aos quais se associa. Para a descrição do hábito alimentar da espécie foram analisados os conteúdos estomacais de cinco exemplares coletados na década de 1990 no Estado do Paraná, tendo sido identificados 116 ítens alimentares. Através da análise dos dados obtidos, conclui-se que P. kronei captura suas presas principalmente em folhas verdes, entre 0,5 e 15m acima do solo, utilizando a manobra "investir-atingir". Alimenta-se predominantemente de artrópodes, sendo que os insetos das ordens Coleoptera... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Restinga Tyrannulet (Phylloscartes kronei) is a recently described and globally threatened species of the family Tyrannidae, whose natural history is poorly known. In this study several information on the natural history of P. kronei were gathered such as several aspects on foraging behavior, association with mixed species bird flocks, feeding habits, the description of the roosting behavior, insights on the reproductive biology, the flying range, interespecific agonistic encounters and moulting. From August 2008 to July 2009, data on this species were collected on a monthly basis in Ilha Comprida (~24º S), São Paulo state, Brazil. In addition, a visit to Guaraqueçaba (25º18'S e 48º19'W), Paraná state, was conducted between 25 July and 01 August 2008. A total of 613 foraging maneuvers were gathered by direct observations with the aid of binoculars with 10x magnification. In all meetings with the species it was reported if individuals were alone, in pairs, in groups or associated with mixed species bird flocks. When mixed species flocks with Restinga Tyrannulets were observed, all species in the flock were identified. Five stomach contents collected in the 1990s in Paraná state were evaluated and 116 food items were identified. The Restinga Tyrannulet captures preys mainly with sally-strikes in green leaves between 0.5 and 15m above the ground. This species feeds mainly on arthropods, especially Coleoptera and Hymenoptera. The observed foraging behaviors and feeding habits were similar to the ones observed in other species of Phylloscartes, but new food items are described for this genus: Anobiidae (Coleoptera), Coccinelidae (Coleoptera), Chalcidoidea (Hymenoptera), Microhymenoptera and two species of fruits (Clusia criuva and Ternstroemia brasiliensis). P. kronei is a sporadic follower of mixed species bird flocks, which had the inclusion of 25 species on their compositions... (Complete abstract click electronic access below) / Mestre
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Comunidade de aves em um remanescente florestal no Noroeste paulista : estrutura trófica, dinâmica e efeitos da sazonalidade /Farina Junior, Oscar. January 2011 (has links)
Orientador: Wagner André Pedro / Banca: Paulo de Marco Junior / Banca: Luiz Dino Vizotto / Resumo: A região Noroeste do estado de São Paulo, bem como microregiões adjacentes, carece de informações concisas sobre a composição floristica e faunística, em especial à avifauna. Esta condição aliada ao alto grau de degradação ambiental apresentado favorece a perda incontestável de biodiversidade. A grande maioria dos remanescentes florestais do interior paulista são representados por pequenos trechos de mata, isolados na maior parte daz vezes por matrizes inóspitas como cultivo de cana-de-açúcar e pastagens. As formações florestais representadas pela Floresta Estacional tipo Semidecidual cobrem a maior parte do interior do estado de São Paulo e, portanto refletem um quadro sazonal relativamente acentuado com dois períodos bastante distintos de seca e chuva. Esta condição sazonal interfere em vários aspectos da historia de vida da fauna inserida na região, especialmente das aves e artrópodes. Neste sentido, procuro-se aqui descrever a estrutura da comunidade de aves em um remanescente florestal de pouco mais de 2.400 ha, com inferências ao grau de endemismo de algumas espécies, grau de conservação e ameaça, habitats e dependência florestal. Ainda, em segundo momento, teve-se por objetivo analisar e avaliar os efeitos da sazonalidade e disponibilidade de presas invertebradas para a comunidade como um todo, mas em especial aos insetívoros. Ao todo foram xi registradas 171 espécies na área de estudo, sendo 95 no remanescente florestal e 76 em áreas de entorno que englobaram ambientes antropizados e aquáticos. Sete espécies foram consideradas endêmicas da Mata Atlântica ou Cerrado, 22 apresentando algum grau de ameaça e 28 espécies dependentes da floresta. Os resultados para as relações sazonais demostraram-se diferentes para as diferentes guildas, sendo que frugívoros tiveram suas populações oscilando mais do que insetívoros e onívoros entre... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Northwest region of São Paulo, as well as adjacent microregions, lacks concise information on the floristic composition and wildlife, especially the avifauna. This condition coupled with the high degree of environmental degradation presented incostestável favors the loss of biodiversity. Most of the interior of forest remnants are represented by small patches of forest, mostly isolated daz times inhospitable matrix as the cultivation of sugar cane and pasture. The forest types represented by seasonal forest type Semidecidual cover most of the state of Sao Paulo, and thus reflect a relatively strong seasonal table with two very distinct periods of drought and rain. This seasonal condition interferes with many aspects of life history fauna inserted into the region, especially birds and arthropods. In this sense, I try here to describe the community structure of birds in a forest remnant of just over 2,400 ha, with inferences to the degree of endemism of some species, conservation status and threat, and dependence on forest habitats. Still, in the second time it was taken to analyze and evaluate the effects of seasonality and availability of invertebrate prey for the community as a whole, but especially the insectivores. Altogether 171 species were recorded in the study area, 95 and 76 in the remaining forest in the surrounding areas have included aquatic and anthropogenic environments. Seven species are endemic to the Atlantic Forest and Cerrado, 22 showing some degree of threat and 28 species of forest-dependent. The xiii results demonstrated for seasonal relationships are different for different guilds, and their populations ranging frugivores had more than insectivores and omnivores between the dry and rainy seasons. The species richness was significantly correlated with invertebrate abundance of foliage. The breeding season of birds recorded in the remaining forest... (Complete abstract click electronic access below) / Mestre
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Detecção do vírus da Influenza Aviária, Paramyxovirus tipo 1 (vírus da Doença de Newcastle), Mycoplasma gallisepticum e Mycoplasma synoviae em aves silvestres e domésticas próximas às granjas avícolas comerciais nas regiões de Mogi das Cruzes e Louveira do Estado de São Paulo / Detection of Influenzavirus, Paramyxovirus I, Mycoplasma gallisepticum and Mycoplasma synoviae in free-ranging birds and backyard chicken around poultry farms in Mogi das Cruzes and Louveira, São Paulo stateGuimarães, Marta Brito 19 December 2012 (has links)
Objetivou-se, neste trabalho, detectar o vírus da Influenza aviária, Paramyxovirus tipo 1 (doença de Newcastle), Mycoplasma gallisepticum e Mycoplasma synoviae, respectivamente pelas técnicas de RT-PCR e PCR, em aves domésticas e aves em vida livre próximas às granjas avícolas nas cidades de Mogi das Cruzes e Louveira do Estado de São Paulo. As aves silvestres foram capturadas, anilhadas, submetidas à avaliação de estado geral e à coleta de suabes de orofaringe e cloaca. As aves de subsistência ou fundo de quintal seguiram o mesmo protocolo com a exceção do anilhamento, e tiveram amostras de sangue coletadas para a pesquisa de anticorpos contra o vírus da Doença de Newcastle, Mycoplasma gallisepticum e Mycoplasma synoviae pela técnica de ELISA indireto. Foram considerados os aspectos da biodiversidade entre as espécies silvestres capturadas e a biossegurança nas granjas. As aves silvestres apresentaram resultados negativos nesta pesquisa, no entanto, Mycoplasma gallisepticum e Mycoplasma synoviae foram detectados pela técnica da PCR nas aves de subsistência, assim como apresentaram títulos de anticorpos para os agentes acima citados e para o Paramyxovirus tipo I. Duas granjas não possuíam medidas de biosseguridade adequadas permitindo o contato de animais de vida livre com as aves de fundo de quintal e com as aves de produção, o que pode facilitar a disseminação de patógenos de interesse para a saúde pública e para a avicultura comercial. / The aim of this study is to detect avian influenza virus, Newcastle disease virus (Paramyxovirus I), Mycoplasma gallisepticum and Mycoplasma synoviae in backyard chicken and wildlife birds around commercial poultry farms using RT-PCR and PCR. The birds were captured with mist nets, identified with alluminium leg rings, subjected to the assessment of clinical conditions and samples were collected by oral and cloacal swabs. The same was done with backyard chicken without the identification with leg rings. Blood samples were collected from backyard chicken and tested for antibodies against Mycoplasma gallisepticum, Mycoplasma synoviae and Paramyxovirus I by indirect ELISA test. This study was conducted in Mogi das Cruzes and Louveira, São Paulo state, where the commercial poultry is considered an activity of great importance. The results were negative to wild birds, but we could detect Mycoplasma gallisepticum and Mycoplasma synoviae by PCR and antibodies titles for Mycoplasma gallisepticum, Mycoplasma synoviae and Newcastle disease in backyard chickens.Two farms didn´t have appropriate biosecurity measures, allowing intense contact with free-living birds, backyard chicken and poultry facilitating spread of pathogens with concern to human health and poultry farms.
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Fragmentação florestal: efeitos em múltipla escala sobre a diversidade de aves em remanescentes florestais no noroeste do Estado de São PauloBispo, Arthur Ângelo [UNESP] 25 February 2010 (has links) (PDF)
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bispo_aa_dr_sjrp.pdf: 1875837 bytes, checksum: 6139dc36c7ba0eb1ab24a12c0fbae7ad (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A fragmentação florestal é uma das principais ameaças a diversidade de aves sendo responsável por grande parte das extinções de espécies em florestas tropicais. Os efeitos da fragmentação florestal sobre a diversidade de espécies em remanescentes devem ser analisados em diferentes escalas com a finalidade de uma melhor interpretação de suas conseqüências sobre cada espécie ou grupo de espécies. Desta forma, este estudo procurou responder três perguntas que geraram as hipóteses de trabalho desenvolvidas em cada capítulo. 1) Quais espécies ocorrem na região noroeste do estado de São Paulo? 2) Como a paisagem do entorno dos remanescentes florestais influencia a riqueza e os grupos funcionais de aves? 3) Na escala do fragmento, como as variáveis ambientais influenciam a riqueza de espécies e a distribuição dos grupos funcionais nos remanescentes florestais? As respostas dessas perguntas seguem um gradiente de relação, de um fator regional até o local. Foram registradas 328 espécies para a região. As origens dos registros permitiram supor que os exclusivamente históricos foram de espécies que não ocorram mais localmente. Essas espécies apresentaram uma forte relação com as categorias propostas, sendo que 75% delas possuem algum tipo de dependência com o ambiente florestal, 63% estão categorizadas como ameaçadas de extinção para o estado de São Paulo e 34% pertencem a algum centro de endemismo. Na escala da paisagem, a distância adotada como paisagem de entorno e os requerimentos ecológicos de cada grupo funcional são responsáveis pelas relações com os componentes da paisagem. Na escala do fragmento, as similaridades entre os remanescentes florestais de acordo com as variáveis estruturais e os grupos funcionais nem sempre foram concordantes. As relações positivas entre o tamanho de área e porcentagem de área nuclear com a riqueza... / Forest fragmentation is one of the major threats to bird diversity and is responsible for most of the extinctions of species in tropical forests. The effects of forest fragmentation on the species diversity in forest remnants should be analyzed at different scales in order to a better interpretation of the consequences for each species or species groups. The presented thesis was therefore structured in three chapters that address questions which reflect these differente scales 1) Which species occur in the northwestern region of the state of São Paulo? 2) How influences the landscapes the species richness and the functional groups of birds? 3) How are species richness and distribution of functional groups in forest remnants influenced by environmental variables on the patch scale? The answers to these questions follow a gradient, of a regional to a local scale. The records of our assessment and former studies, performed in this region, include 328 species for the northwestern region, but show discrepancies in species composition between the former and the present status. Some species have thus apparently vanished regionally. We structured the records in three categories representing forest dependence, threat status, and endemism. The species that have regionally vanished show a strong relationship with the categories: 75% depend somehow on the forest habitat, 63% are categorized as endangered in the state of São Paulo, and 34% are endemic to four endemism centers. At the landscape scale, the surrounding landscape and the ecological requirements of each functional group describe the relations of bird functional groups and bird species richness to the components of the landscape. On patch scale the multivariate analysis showed that the similarities between remnants according structural variable and functional groups, sometimes disagree. The positive relationship... (Complete abstract click electronic access below)
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Detecção do vírus da Influenza Aviária, Paramyxovirus tipo 1 (vírus da Doença de Newcastle), Mycoplasma gallisepticum e Mycoplasma synoviae em aves silvestres e domésticas próximas às granjas avícolas comerciais nas regiões de Mogi das Cruzes e Louveira do Estado de São Paulo / Detection of Influenzavirus, Paramyxovirus I, Mycoplasma gallisepticum and Mycoplasma synoviae in free-ranging birds and backyard chicken around poultry farms in Mogi das Cruzes and Louveira, São Paulo stateMarta Brito Guimarães 19 December 2012 (has links)
Objetivou-se, neste trabalho, detectar o vírus da Influenza aviária, Paramyxovirus tipo 1 (doença de Newcastle), Mycoplasma gallisepticum e Mycoplasma synoviae, respectivamente pelas técnicas de RT-PCR e PCR, em aves domésticas e aves em vida livre próximas às granjas avícolas nas cidades de Mogi das Cruzes e Louveira do Estado de São Paulo. As aves silvestres foram capturadas, anilhadas, submetidas à avaliação de estado geral e à coleta de suabes de orofaringe e cloaca. As aves de subsistência ou fundo de quintal seguiram o mesmo protocolo com a exceção do anilhamento, e tiveram amostras de sangue coletadas para a pesquisa de anticorpos contra o vírus da Doença de Newcastle, Mycoplasma gallisepticum e Mycoplasma synoviae pela técnica de ELISA indireto. Foram considerados os aspectos da biodiversidade entre as espécies silvestres capturadas e a biossegurança nas granjas. As aves silvestres apresentaram resultados negativos nesta pesquisa, no entanto, Mycoplasma gallisepticum e Mycoplasma synoviae foram detectados pela técnica da PCR nas aves de subsistência, assim como apresentaram títulos de anticorpos para os agentes acima citados e para o Paramyxovirus tipo I. Duas granjas não possuíam medidas de biosseguridade adequadas permitindo o contato de animais de vida livre com as aves de fundo de quintal e com as aves de produção, o que pode facilitar a disseminação de patógenos de interesse para a saúde pública e para a avicultura comercial. / The aim of this study is to detect avian influenza virus, Newcastle disease virus (Paramyxovirus I), Mycoplasma gallisepticum and Mycoplasma synoviae in backyard chicken and wildlife birds around commercial poultry farms using RT-PCR and PCR. The birds were captured with mist nets, identified with alluminium leg rings, subjected to the assessment of clinical conditions and samples were collected by oral and cloacal swabs. The same was done with backyard chicken without the identification with leg rings. Blood samples were collected from backyard chicken and tested for antibodies against Mycoplasma gallisepticum, Mycoplasma synoviae and Paramyxovirus I by indirect ELISA test. This study was conducted in Mogi das Cruzes and Louveira, São Paulo state, where the commercial poultry is considered an activity of great importance. The results were negative to wild birds, but we could detect Mycoplasma gallisepticum and Mycoplasma synoviae by PCR and antibodies titles for Mycoplasma gallisepticum, Mycoplasma synoviae and Newcastle disease in backyard chickens.Two farms didn´t have appropriate biosecurity measures, allowing intense contact with free-living birds, backyard chicken and poultry facilitating spread of pathogens with concern to human health and poultry farms.
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Vtáčie spoločenstvá pozdĺž výškového gradientu na Kamerunskej hore z pohľadu odchytových dát / Bird Communities Along the Altitudinal Gradient on Mt. Cameroon: Perspectives from Mist NetsPetruf, Miroslav January 2019 (has links)
in English Mt. Cameroon is a hotspot of diversity and endemism in Africa. Recent research of avian bird communities along the elevational gradient on Mt. Cameroon based on point counts has shown low-elevation plateau of species richness. At the same time, range-restricted montane populations of birds on Mt. Cameroon are unusually abundant if compared to lowland species. I analysed data on community composition, species richness and abundance of birds using an alternative quantitative method - 200 m of understory mist nets erected for three consecutive days across seven elevational plots along the forested gradient of the Mt. Cameroon. First, I looked at the technical limits of this method and confirmed the general opinion that they are better at detecting small birds below 33 g, and that they mostly detected fewer individuals after the first day and always detected fewer new species after the first day of mist-netting. Mist nets detected high proportions of ground-feeding and understory birds and low proportions of birds foraging in higher strata in the lowland forest, which has a scarce understory and a dense canopy. Mist nets recorded similar proportions of birds foraging in all forest strata in the vastly open mid-elevation forest, which has a dense herbaceous understory. They detected higher...
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A Multi-Scale Approach to Defining Historical and Contemporary Factors Responsible for the Current Distribution of the White-bellied Sea-Eagle Haliaeetus leucogaster (Gmelin, 1788) in AustraliaShephard, Jill, n/a January 2004 (has links)
The White-bellied Sea-Eagle Haliaeetus leucogaster is widespread in Australia, but has been the subject of conservation concern due to suggested localised declines and extinctions. Regionalised monitoring programmes have addressed some aspects of local concern, however a broader approach is needed to gain an understanding of large-scale processes affecting long-term persistence at scales equivalent to the species Australian range. Ultimately, the ability to predict change in population size over time accurately depends on the scale of analysis. By necessity, ecological studies using direct sampling techniques are often made across spatial scales smaller than a species geographic range and across relatively short time frames. This seems counter-intuitive considering that long-term species persistence is often dependent on large-scale processes. The principal aim of this thesis was to identify historical and contemporary forces responsible for the current pattern of population structure in H. leucogaster. This required a multi-scale approach, and the resulting research uses genetic, distributional and morphometric data. Haliaeetus leucogaster is a large territorial raptor that historically has been associated with coastal regions, lakes and perennial river systems. It has an extensive worldwide distribution from the western coast of India throughout the Indomalaysian region, Papua New Guinea and Australia. By virtue of the species' large-scale distribution, in Australia it is fairly cosmopolitan in its use of habitat and prey types. Haliaeetus leucogaster is monomorphic for adult plumage colouration, but in body size displays reversed sexual dimorphism with female birds significantly larger. A discriminant function based on 10 morphometric characters was 100% effective in discriminating between 19 males and 18 females that had been sexed using molecular genetic methods. Re-classification using a jackknife procedure correctly identified 92% of individuals. The discriminant function should be a viable alternative to genetic sexing or laparoscopy for a large proportion of individuals within the Australo-Papuan range of this species; and can also be used to identify a small proportion of "ambiguous" individuals for which reliable sexing will require those other techniques. I used mitochondrial (mtDNA) control region sequence data to investigate the current distribution of genetic variation in this species at the continental level and within and between specified regional units. I was specifically interested in identifying breaks in genetic connectivity between the west and east of the continent and between Tasmania and the Australian mainland. Overall, genetic diversity was low and there was no significant level of genetic subdivision between regions. The observed genetic distribution suggests that the population expanded from a bottleneck approximately 160 000 years ago during the late Pleistocene, and spread throughout the continent through a contiguous range expansion. There is insufficient evidence to suggest division of the population into different units for conservation management purposes based on the theoretical definition of the 'evolutionary significant unit'. It is clear from the analysis that there are signatures of both historical and contemporary processes affecting the current distribution. Given the suggestion that population expansion has been relatively recent, additional sampling and confirmation of the perceived pattern of population structure using a nuclear marker is recommended to validate conservation monitoring and management at a continental scale. To determine the existence of perceived population declines across ecological time scales, I analysed the Australian Bird Atlas Data to identify the extent and pattern of change in range and density of the species between three Atlas Periods (1901-1976, 1977-1981 and 1998-2001) using a new standardised frequency measure, the Occupancy Index (OI) for 1° blocks (approx. 100km2) across the continent. At the continental scale, there was no significant difference in the spatial extent of occupancy between Atlas Periods. However, there were considerable changes in frequency and range extent between defined regions, and there were distinct differences in the pattern of change in OI between coastal and inland blocks over time. Coastal blocks showed much more change than inland blocks, with a clear increase in the use of coastal blocks, accompanied by a decrease in inland blocks, during the 1977-1981 Atlas Period, relative to both other Atlas Periods. The over-riding factor associated with distributional shifts and frequency changes was apparently climatic fluctuation (the 1977-1981 period showing the influence of El Nino associated drought). The impression of abundance was strongly dependent on both the temporal and spatial scale of analysis. To test for correspondence between geographic variation in morphology and geographic variation in mtDNA I analysed morphometric data from 95 individuals from Australia and Papua New Guinea. First, the degree of morphometric variation between specified regions was determined. This was then compared with the pattern of genetic differentiation. There was a strong latitudinal cline in body dimensions. However, there was no relationship between morphometric variation and patterns of genetic variation at least for mtDNA. Females showed a pattern of isolation by distance based on morphometric characters whereas males did not. Three hypotheses to explain the pattern of morphometric variation were considered: phenotypic plasticity, natural selection and secondary contact between previously isolated populations. I conclude that the pattern of morphometric variation is best explained by the suggestion that there is sufficient local recruitment for natural selection to maintain the observed pattern of morphometric variation. This implies that gene flow may not be as widespread as the mtDNA analysis suggested. In this instance either the relatively recent colonisation history of the species or the inability of the mtDNA marker to detect high mutation rates among traits responsible for maintaining morphometric variation may be overestimating the levels of mixing among regions. As might be expected given the physical scale over which this study was conducted, the pattern of genetic, morphometric and physical distribution varied dependent on the scale of analysis. Regional patterns of genetic variation, trends in occupancy and density and morphometric variation did not reflect continental patterns, reinforcing the contention that extrapolation of data from local or regional levels is often inappropriate. The combined indirect methodologies applied in this study circumvent the restrictions imposed by direct ecological sampling, because they allow survey across large geographic and temporal scales effectively covering the entire Australian range of H. leucogaster. They also allow exploration of the evolutionary factors underpinning the species' current distribution.
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Birds in coffee agroforestry systems of West Lampung, SumatraO'Connor, Trudy Rochelle January 2005 (has links)
In the Sumberjaya district of West Lampung, Indonesia, there has been widespread replacement of rainforest by robusta coffee. However, few studies have explored the relationship between birds and coffee gardens in Southeast Asia. This study examines the use of coffee gardens and other habitats by birds in the Sumberjaya and Pesisir regions. Birds and their habitat use were surveyed, as were structural and floristic vegetation features. Interviews with farmers indicated land management practices and limitations, as well as local perceptions of shade trees, birds and conservation programs. There were clear differences in bird diversity and assemblage uniqueness between types of coffee gardens. Over the region, ' multistrata ' gardens supported the greatest number of species. However, all coffee types had lower taxonomic diversity of birds than did forest. Frugivores, and birds of high conservation dependence, were poorly represented in coffee gardens. Microhabitat use by birds was significantly different between habitats, and it appeared that the birds did make use of structural features as they became available. Farmers indicated that shade trees had benefits such as sheltering coffee plants, and providing produce, but were also apprehensive about over - shading. Many claimed that bird assemblages have changed, yet while describing habitat loss as a past problem, few people felt that forest loss would cause bird deaths. Most farmers believed that coffee gardens had potential to provide useful bird habitat. Interviewees believed that both Government and the community were responsible for conservation. Many showed interest in co - operative conservation programs, particularly if they allowed farmers flexibility, or if they involved incentives related to land tenure. There was also interest in market - based schemes such as eco - certification. The primary action needed for conservation of Sumberjaya ' s birds is to minimise ongoing forest degradation. This may be achieved by linking incentives such as land tenure to forest protection. Capacity to create a certified coffee scheme may be limited by poor coffee quality and inappropriate garden characteristics. Farms maintained primarily for coffee production showed limited value for rainforest - adapted birds. However, the Krui damar gardens suggest a model, which as a forest buffer zone, may allow a more gentle spatial transition from agricultural to forest conditions. / Thesis (Ph.D.)--School of Social Sciences, 2005.
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The causes of nest failure and effects of inbreeding depression in a historically small population of New Zealand Stewart Island robinsLaws, Rebecca, n/a January 2009 (has links)
Inbreeding depression is one of the factors that can increase the risk of extinction of small populations, and therefore understanding its effects is currently an important issue in conservation biology. Until recently, few studies on inbreeding depression were carried out in wild populations. These recent studies have highlighted the variability in detecting inbreeding depression among natural populations and the multitude of factors that can influence its expression. Many of the factors affecting inbreeding depression in wild populations remain largely unexplored and most of the recent studies in this area have tended to focus on incidents of inbreeding in populations with a history of large population size.
The aim of this study is to investigate the relative importance inbreeding depression has had on individual fitness parameters in a population of New Zealand's Stewart Island robins Petroica australis rakiura introduced to Ulva Island. This island population has historically gone through several population bottlenecks. Four main factors that potentially influence the rate of inbreeding and the extent of inbreeding depression, were investigated: environmental variability, life history stage, genetic load and dispersal. Generalized Linear Mixed Modelling was first used to determine how weather affected nest survival. Weather effects were then incorporated into models containing demographic factors to control for environmental variability, and finally parental, maternal and paternal inbreeding co-efficients (=f) were added to models to determine the relative importance of inbreeding depression. Interactions between inbreeding depression and environmental factors were explored. Three different life history stages were compared to determine the differences in inbreeding depression at each stage as well as cumulative effects over time. The genetic load of the population was estimated using lethal equivalents allowing for standardised comparison of inbreeding depression with other species. The likelihood of inbreeding in the population was also explored by investigating the factors affecting dispersal patterns and evaluating evidence for inbreeding avoidance.
Inbreeding depression was found to be mild in the robin population. Weather did not have strong effects on nest survival or interactions with inbreeding. Female age was the only factor interacting with inbreeding, with younger inbred females experiencing significantly reduced offspring juvenile survival. Parental and paternal f did not significantly affect brood survival at any life history stage, however, maternal f showed significant effects on nest juvenile survival with the strongest effect occurring when survival was examined cumulatively over all life history stages. The Stewart Island robin had a relatively low lethal equivalent value compared to the closely related North Island robin and other avian species. This difference was associated with the Stewart Island robin having a low genetic load, most likely due to historical genetic purging during periods of population bottleneck. The Ulva Island robin population did not appear to be avoiding inbreeding through dispersal. Dispersal distance was most strongly influenced by the location of the natal nest of the dispersing offspring.
In conclusion, the genetic history of the population was likely to have had the strongest impact on the severity of inbreeding depression in the Ulva Island robin population. The results of the thesis highlight the need to examine a number of factors to be able to explain variability in inbreeding depression among populations.
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