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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.
1

Ecologia alimentar de aves inset?voras de um fragmento de mata dec?dua do extremo norte da Mata Atl?ntica

Souto, Glauber Henrique Borges de Oliveira 30 June 2010 (has links)
Made available in DSpace on 2014-12-17T14:10:22Z (GMT). No. of bitstreams: 1 GlauberHBOS_DISSERT.pdf: 1092481 bytes, checksum: e18c958f4fa280552deed9ab75e1ca3b (MD5) Previous issue date: 2010-06-30 / The diet study of birds has contributed historically as a model for use to understanding ecological patterns and strategies used by several other groups of vertebrates, which are observed in season patterns and temporal availability of resources, and other. This study has as objective generate information concerning the diet of insectivorous birds during rainy season and dry season, as well as analyze Index food importance, niche overlap, niche breadth, electivity, and seasonal availability of prey. The study was conducted in a fragment of about 270 ha (center coordinates and 5 ? 53'S 35 ? 23'W). The sampling of birds occurred between March 2008 and December 2009 in three pre-established trails. Catches of birds were performed using 10 mist nets placed in line, where each trails was sampled once a month. Samples of pellets were obtained by means of tartar emetic. Sampling of availability of prey occurred between February 2009 to December 2009. We used two methods of sampling (pitfall traps and Shake cloths). We captured 269 individuals of 21 species of insectivorous birds. We collected 4116 invertebrates of which 3259 in the rainy season and 857 in the dry season. We obtained 174 samples stomach, where 10 species were exclusively insectivorous diet, nine fed on insect/plant material, an insect/plant material/vertebrate and one for insect/vertebrate. During the rainy season was observing difference between the consumption of items with higher food importance. The Coleoptera was item with higher food importance (73%), followed by Formicidae (7%) and Araneae (6%). During the dry season, no difference was found difference between the consumption of items with higher food importance. The Coleoptera was item with higher food importance (34%), followed by seeds (29%) and Formicidae (18%). The highest levels of niche overlap occurred during the rainy season, while the dry season was characterized by high levels of niche 11 segregation. This indicates that the local insectivorous birds community was structured differently between periods. No was found correlation between the values of niche breadth to the mean weight of the body size. We observed seasonal patterns in prey availability, with the peak availability of invertebrates observed seasonal patterns in rainy season. The insectivorous birds selected the same species richness during both periods, showing a specialized diet. Thamnophilus pelzelni was the only species that had their diet influenced by seasonality. Regarding the overall diet of insectivorous birds, observed a high consumption of prey, whose food availability caused the birds could invest and increase their food resources / O estudo da dieta de aves tem contribu?do, historicamente, como modelo de uso para o entendimento de padr?es e estrat?gias ecol?gicas utilizados por v?rios outros grupos de vertebrados, nos quais s?o observados padr?es sazonais e temporais na disponibilidade de recursos e outros. O presente trabalho objetivou gerar informa??es referentes ? dieta de aves inset?voras durante os per?odos chuvoso e seco, bem como analisar import?ncia alimentar, valores de sobreposi??o alimentar, amplitude de nicho, eletividade e disponibilidade de presas durantes as esta??es chuvosa e seca. O estudo foi realizado em um fragmento com cerca de 270 ha (coordenadas centrais 5?53 S e 35?23 W). O per?odo de amostragem das aves ocorreu entre mar?o de 2008 a dezembro de 2009, em tr?s trilhas pr?-estabelecidas. As capturas das aves foram realizadas por meio de 10 redes ornitol?gicas dispostas em linha, onde cada linha de rede foi colocada em uma das trilhas, sendo uma amostragem de aves realizadas em uma ?nica trilha por m?s. As amostras de regurgitos foram obtidas por meio do t?rtaro em?tico. As amostragens de disponibilidade de presas ocorreram entre fevereiro de 2009 a dezembro de 2009, sendo utilizados amostragens no solo (pitfall traps) e na folhagem (shake cloths). Capturamos 269 indiv?duos de 21 esp?cies de aves inset?voras. Foram coletados 4.116 invertebrados, dos quais 3.259 no per?odo chuvoso e 857 no per?odo seco. Obtivemos 174 amostras estomacais, onde 10 esp?cies tiveram dieta exclusivamente inset?vora, 9 alimentaram-se de inseto/material vegetal, 1 de inseto/material vegetal/vertebrado e 1 por inseto/vertebrado. Durante o per?odo chuvoso foi observada diferen?a entre o consumo dos itens com maior Import?ncia 9 Alimentar, sendo Coleoptera o item com maior Import?ncia Alimentar (73%), seguido por Formicidae (7%) e Araneae (6%). Durante o per?odo seco, n?o foi encontrada diferen?a entre o consumo dos itens com maior import?ncia Alimentar, Sendo Coleoptera o item com maior Import?ncia Alimentar (34%), seguido por sementes (29%) e Formicidae (18%). Os maiores ?ndices de sobreposi??o de nicho ocorreram durante o per?odo chuvoso, enquanto o per?odo seco foi caracterizado pelos maiores valores de segrega??o de nicho. Isto indica que a comunidade de aves inset?voras local esteve estruturada de forma diferenciada entre os per?odos. N?o foi encontrada correla??o entre os valores de Amplitude de nicho com os pesos m?dios das aves, mostrando que o tamanho do nicho ocupado pelas aves n?o tem rela??o com o seu tamanho corporal. Foram observados padr?es sazonais na disponibilidade de presas, sendo o pico da disponibilidade de invertebrados observado durante o per?odo chuvoso. As aves inset?voras selecionaram a mesma riqueza de esp?cies durante os dois per?odos, mostrando uma dieta especializada. Thamnophilus pelzelni foi a ?nica esp?cie que teve a sua dieta influenciada pela sazonalidade. No que diz respeito a dieta global das aves inset?voras, observamos um elevado consumo de presas, cuja grande disponibilidade de alimento fez com que as aves pudessem investir e aumentar os seus recursos alimentares

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