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1.
An Acad Bras Cienc ; 90(3): 2851-2853, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29947677

RESUMO

Sittace flaviventris Wagler, 1832 was the name given to Azara's No. 276 "Maracaná cabeza y encuentro roxos", but since then the identity of the species has remained a mystery. Based on a tail-less domestic individual, it has most often been attributed to an aberrant Aratinga parakeet, and is currently considered a doubtful taxon. In this note the identity of "Azara's Parakeet" is confirmed as Red-spectacled Amazon Amazona pretrei (Temminck, 1830), a species that still occurs today in the region from where Azara described it. Sittace flaviventris is thus a junior synonym of Amazona pretrei.


Assuntos
Periquitos/anatomia & histologia , Periquitos/classificação , Animais , Brasil
2.
Mol Ecol ; 22(7): 2011-27, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23397908

RESUMO

In cooperative species, helping behaviour and reproductive success can be correlated, but understanding this correlation is often impaired by the difficulty to correctly infer causation. While helpers can incur costs by participating in brood care, it is yet unclear if their help depends on their individual quality. We address these questions in the previously unknown cooperative breeding system of the endangered El Oro parakeet (Pyrrhura orcesi). Specifically, we ask (i) whether breeders benefit directly from helpers by an enhanced reproductive success and if so, (ii) whether the amount of this potential benefit is regulated by the quality of contributing group members. Groups consist of a dominant breeding pair accompanied by helpers, but cooperation is not obligate. Microsatellite heterozygosity was used to assess individual quality; its suitability as indicator of quality was reflected in the positive relationship between offspring heterozygosity and recruitment into the population. The reproductive success of breeding pairs depended on helper (genetic) quality and the number of helpers. This relationship occurred on two different levels: clutch size and fledging success, indicating (i) that females profit from high-quality helpers and probably adjust clutch size accordingly and (ii) that the helpers increase fledging success. Congruently, we found that offspring body condition is positively affected by helper quality, which is most probably explained by the increased feeding rates when helpers are present. We suggest a causal link between cooperation and reproductive success in this frugivorous, endangered parakeet. Further, helper (genetic) quality can be a relevant factor for determining reproductive fitness in cooperative species, particularly in small and bottlenecked populations.


Assuntos
Espécies em Perigo de Extinção , Periquitos/genética , Reprodução/genética , Animais , Cruzamento , Tamanho da Ninhada , Conservação dos Recursos Naturais , Comportamento Alimentar , Feminino , Aptidão Genética , Heterozigoto , Masculino , Repetições de Microssatélites , Periquitos/classificação
3.
Braz J Biol ; 67(2): 243-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17876434

RESUMO

The genus Pyrrhura includes small to medium-sized parakeets, which inhabit both low and dry alongside tall rainforests, mainly in South America. Pyrrhura molinae is still common, year round, in the markedly seasonal forests of western Brazil. This parakeet, as well as most Neotropical parrots, continues to be poorly understood. Hence, in the present study I examined their foraging ecology both in a highly deciduous and in a semi-deciduous forest in western Brazil. In addition, I assessed the relationship between food resource production (flowers and fruits), and the diet of this parakeet. Pyrrhura molinae exhibited a flexible diet consisting of 16 tree species, from which it consumed flowers (three species), seeds (three species), fruit pulp or aril (four species), and both pulp and seeds (six species). Parakeets consumed a wide array of fleshy fruits in the semi-deciduous forest, especially Cecropia pachystachya catkins. Conversely, in the highly deciduous forest they extensively foraged for figs (70% of the diet), in addition to nectar and seeds from dry fruits. Ficus calyptroceras, besides being abundant, bore fruits year round, and was substantially used by parakeets every month. Potentially, by exploiting a diverse set of plant food resources, and particularly due to the substantial use of figs, asynchronously produced, Pyrrhura molinae persists during the long dry season in the markedly seasonal forests of western Brazil.


Assuntos
Ecossistema , Comportamento Alimentar/fisiologia , Periquitos/fisiologia , Árvores , Animais , Brasil , Preferências Alimentares , Periquitos/classificação , Estações do Ano
4.
Braz J Biol ; 64(4): 867-77, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15744428

RESUMO

Parakeets usually forage for massive and ephemeral plant resources at forest canopies. Fruit pulp is widely cited as a major food resource for these birds, which often eat seeds and nectar. In this study, I assessed flower and fruit production at a gallery forest in the Pantanal flood plain (Brazil) in order to evaluate the relationship between food resource production and abundance of a common parakeet, Brotogeris chiriri. Also, I evaluated the relationship between food resource production and foraging activity. Parakeet abundance varied markedly along the year, coinciding with massive episodes of flower and fleshy fruit availability. Inga vera nectar, intensely used during the latter part of dry season, was by far the most exploited food item by parakeets when they were very abundant. The nectar comprised 34% of the parakeets' diet (N = 131 feeding records) at the gallery forest, while fleshy fruits made up the rest. Parakeets principally exploited fruits of Cecropia pachystachya and Ficus luschnathiana, besides palm fruits and Inga vera arils. The consistent relationship between foraging activity and parakeet abundance, as well as the coincidence between fluctuations of these parameters and availability of major food resources, suggests that food availability mostly influenced B. chiriri occurrence in the gallery forest. Furthermore, I found no evidence for gallery forest use for roosting and/or breeding, in spite of the fact that such factors usually influence local parakeet abundance.


Assuntos
Ecossistema , Comportamento Alimentar/fisiologia , Flores , Frutas , Periquitos/fisiologia , Animais , Brasil , Periquitos/classificação , Densidade Demográfica , Estações do Ano
5.
Mitochondrial DNA ; 25(5): 365-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23815322

RESUMO

Socorro Conure (Aratinga brevipes.Aratinga holochlora brevipes) is a parrot endemic to the Island of Socorro. According to some taxonomists the species is considered a subspecies of Green Conure (Aratinga holochlora). Some other classifications treat brevipes as a separate species based on relatively minor morphological differences between both species/subspecies. However, taxonomic position of Aratinga brevipes was never determined by molecular research. We sequenced full mitochondrial genome of the species and constructed phylogenetic tree using sequences of mitochondrial ND2 gene from A. brevipes and some other representatives of Conures group. Our results showed, that despite Aratinga brevipes is closely related to Aratinga holochlora, this Conure should be treated as a separate species.


Assuntos
Genoma Mitocondrial , Periquitos/classificação , Periquitos/genética , Animais , Espécies em Perigo de Extinção , Genes Mitocondriais , Filogenia , Análise de Sequência de DNA/métodos , Especificidade da Espécie
6.
Mitochondrial DNA ; 24(4): 336-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23351080

RESUMO

Blue-crowned Parakeet (Aratinga acuticaudata) is a South American parrot species with a taxonomic position not confirmed by molecular studies. We sequenced full mitochondrial genome and constructed phylogenetic tree using sequences of mitochondrial ND2 gene from A. acuticaudata and some other representatives of Conures group. Our results confirmed previously described distribution of Aratinga species into three clades, but surprisingly did not classify Blue-crowned Parakeet to any of them. We found that A. acuticaudata shares the closest relationship with Diopsittaca nobilis and forms a separate clade together with Guaruba guarouba and Leptosittaca branickii species with a significant node. Our results confirm lack of monophyly of the genus Aratinga and underline the need of its taxonomic revision.


Assuntos
DNA Mitocondrial/genética , Genes Mitocondriais/genética , Genoma Mitocondrial/genética , Periquitos/classificação , Periquitos/genética , Filogenia , Animais , Sequência de Bases , Teorema de Bayes , Funções Verossimilhança , Modelos Genéticos , Dados de Sequência Molecular , Análise de Sequência de DNA , Especificidade da Espécie
7.
Braz. j. biol ; 67(2): 243-249, May 2007. graf, tab
Artigo em Inglês | LILACS | ID: lil-459996

RESUMO

The genus Pyrrhura includes small to medium-sized parakeets, which inhabit both low and dry alongside tall rainforests, mainly in South America. Pyrrhura molinae is still common, year round, in the markedly seasonal forests of western Brazil. This parakeet, as well as most Neotropical parrots, continues to be poorly understood. Hence, in the present study I examined their foraging ecology both in a highly deciduous and in a semi-deciduous forest in western Brazil. In addition, I assessed the relationship between food resource production (flowers and fruits), and the diet of this parakeet. Pyrrhura molinae exhibited a flexible diet consisting of 16 tree species, from which it consumed flowers (three species), seeds (three species), fruit pulp or aril (four species), and both pulp and seeds (six species). Parakeets consumed a wide array of fleshy fruits in the semi-deciduous forest, especially Cecropia pachystachya catkins. Conversely, in the highly deciduous forest they extensively foraged for figs (70 percent of the diet), in addition to nectar and seeds from dry fruits. Ficus calyptroceras, besides being abundant, bore fruits year round, and was substantially used by parakeets every month. Potentially, by exploiting a diverse set of plant food resources, and particularly due to the substantial use of figs, asynchronously produced, Pyrrhura molinae persists during the long dry season in the markedly seasonal forests of western Brazil.


O gênero Pyrrhura é constituido de pequenos periquitos comuns tanto em matas secas quanto úmidas, sobretudo da América do Sul. Pyrrhura molinae ocorre durante o ano todo em florestas altamente sazonais do oeste brasileiro. Essa espécie, bem como a maioria dos psitacídeo, permanece pouco conhecida. Portanto, nesse estudo, foi examinada a ecologia alimentar de P. molinae em dois tipos de florestas secas (altamente decídua e semidecídua), do oeste brasileiro, bem como as relações entre a produção de flores frutos e a utilização desses recursos. Pyrrhura molinae exibiu uma dieta flexível em que utilizou recursos de 16 espécies arbóreas, sendo flores de três, sementes de outras três, a polpa dos frutos ou arilo de quatro espécies e, simultaneamente, a polpa e semente de seis espécies. Os periquitos consumiram principalmente frutos carnosos na floresta semidecídua, especialmente as infrutescências de Cecropia pachystachya. Por outro lado, na floresta altamente decídua, figos predominaram na dieta (70 por cento dos registros de alimentação), somados ao néctar e sementes de frutos secos. Ficus calyptroceras, além de abundante produziu frutos o ano todo, que foram consumidos substancialmente pelos periquitos mês a mês. Presumivelmente, por explorar uma ampla variedade de recursos vegetais e subsistir, em grande parte, a base de figos produzidos assincronicamente, Pyrrhura molinae persiste à severa estação seca nas matas decíduas do oeste brasileiro.


Assuntos
Animais , Ecossistema , Comportamento Alimentar/fisiologia , Periquitos/fisiologia , Árvores , Brasil , Preferências Alimentares , Periquitos/classificação , Estações do Ano
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