Avifauna of the region of the Volta Grande Hydroelectric Power Plant in Southeast Brazil

The Volta Grande region in the Brazilian state of Minas Gerais is classified as of “High Biological Importance” for the conservation of birds in the state. Despite this, the avifauna of the region has yet to be adequately sampled, as evidenced by the few papers on the region in ornithological literature. The results of an avifaunal inventory conducted between March 2013 and January 2014 in five sites located throughout the region of the Volta Grande Hydroelectric Power Plant in Southeast Brazil are presented. Point-counts, ad libitum observations and mist-nets recorded 224 species for the region, with insectivorous and omnivorous being the predominant feeding habits. Species that are “independent” of forest habitats comprised 52% of the recorded species. Three species are endemics of the Cerrado, 83 are migratory and 32 are under some degree of threat of extinction. These findings demonstrate that the region of the Volta Grande Hydroelectric Power Plant is important for bird conservation. Additional inventories, adequate management plans and public policies aimed the preserving species are needed for more effective conservation of the biodiversity of the studied region

Avifauna em fragmentos de mata ciliar e áreas adjacentes no Baixo Rio Grande, Sudeste do Brasil.

As florestas tropicais estão sendo devastadas através do desmatamento e da fragmentação do habitat. Este processo leva à interrupção de habitats grandes e contínuos e à formação de uma paisagem composta por fragmentos menores e isolados do habitat original, envoltos por uma matriz pobremente diversificada. Sobre a comunidade de aves, a fragmentação leva à redução da riqueza de espécies florestais, à inibição à dispersão, à diminuição da diversidade genética e à redução no fitness. As aves, por sua relativa facilidade de detecção na natureza, pelo alto nível de conhecimento sobre sua classificação taxonômica e por suas respostas rápidas às alterações ambientais, atuam como um importante grupo bioindicador no manejo de paisagens terrestres. No Cerrado, as matas ciliares correspondem às formações florestais associadas aos cursos d’água sendo consideradas habitats importantes para a manutenção de uma elevada riqueza local da avifauna. Diversos autores têm alertado para a importância de se conservar as matas ciliares, porém, uma significativa parcela de matas ciliares da região sudeste do Brasil tem sido destruída. O presente estudo teve como objetivo principal verificar se a sazonalidade e variáveis ambientais influenciam a riqueza e a composição da comunidade de aves em cinco áreas localizadas ao longo do reservatório da UHE Volta Grande, sudeste do Brasil. Durante oito meses, entre abril 2013 e janeiro 2014, a comunidade de aves destas áreas foi amostrada através de três metodologias: pontos fixos, transecções e captura com redes de neblina. Foram registradas 225 espécies distribuídas em 58 famílias e 24 ordens. Através de Modelos Lineares Generalizados (GLMs) foi possível verificar que a riqueza de aves das matas ciliares foi influenciada positivamente pelo tamanho dos fragmentos, pela riqueza e abundância de espécies vegetais e pela cobertura florestal na paisagem circundante aos fragmentos. Já a urbanização influenciou negativamente. A riqueza e composição da avifauna variaram significativamente entre as estações seca e chuvosa. Assim sendo, o presente estudo contribui para o conhecimento de como e quais variáveis ambientais estão envolvidas na dinâmica da avifauna em uma região fortemente fragmentada e impactada por ações antrópicas, permitindo o desenvolvimento de adequados planos de manejo a fim de garantir a efetiva conservação da avifauna local.Tropical forests are being devastated by deforestation and habitat fragmentation. This process leads to disruption of major and continuous habitat and to formation of a landscape composed of smaller and isolated fragments from the original habitat, surrounded by a poorly diverse array. On the bird community, fragmentation leads to a reduction of forest species richness, to inhibiting the dispersion, to a reduction of genetic diversity and in fitness. The birds, by their relative facility of detection in nature, by the high level of knowledge about their taxonomic classification and by its rapid responses to environmental changes, act as an important bio-indicator group in the terrestrial landscapes management. In the Cerrado, the riparian forests correspond to forest formations associated with watercourses being considered important habitats for maintaining high local birdlife richness. Several authors have warned of the importance to conserving riparian forests, however, a significant portion of riparian forests of southeastern Brazil has been destroyed. This study aimed to verify if the seasonal and environmental variables influence the richness and the bird community composition in five areas located along the reservoir of UHE Volta Grande, southeastern Brazil. For eight months between April 2013 and January 2014, the bird community of these areas was sampled through three methods: point counts, transects and capture with mist nets. 225 species distributed in 58 families and 24 orders were recorded. Through Generalized Linear Models (GLMS) was observed that the birds richness of riparian forests was positively influenced by the patch size, by the richness and abundance of plant species and by the forest cover in the surrounding landscape. Urbanization influenced negatively. The richness and composition of the avifauna varied significantly between the dry and rainy seasons. Thus, this study contributes to the knowledge of how and what environmental variables are involved in the dynamics of birds in a region heavily fragmented and impacted by human activities, enabling the development of adequate management plans to ensure the effective conservation of local avifauna

Species-specific outcomes of avian gut passage on germination of Melastomataceae seeds

Background and aims – Frugivory and seed dispersal are of major importance for plant recruitment and distribution. However, few studies have addressed the effects of gut passage on seed germination in complex fruit-frugivore systems involving multiple species. Here, we examined whether gut passage by seven bird species affects seed germination of eight Melastomataceae species from the Brazilian Cerrado, a Neotropical savanna. Methods – We take advantage of the generalist dispersal system of melastomes in order to compare the dispersal quality among bird species by contrasting seed germination of hand-cleaned, gut-passed seeds and seeds within intact fruits. We studied gut passage effects on seed germination percentage and mean germination time (MGT) of Clidemia urceolata and seven Miconia species. Key results – Less than 4% germinability was observed for seeds within intact fruits across all plant species, indicating that seed cleaning is required prior to germination. The action of guts on the seeds had non-significant or minor additive effects on germinability compared to hand-cleaned seeds depending on the plant species. Gut treatment had no effect on MGT of two species and minor effects on other three species. However, mechanical/chemical effect significantly decreased MGT of C. urceolata and M. albicans while it increased MGT of M. ibaguensis. There were significant species-dependent effects depending on both bird and plant species, suggesting that species-specific outcomes arise from Neotropical fruit-frugivore interactions in plants with generalist dispersal systems. Conclusions – Germination enhancement deriving from gut scarification was not observed for all species, but seed cleaning seems to be an important benefit provided by frugivores to Cerrado melastomes. The variable outcomes resulting from complex fruit-frugivore interactions potentially affect the recruitment of Cerrado melastomes

Rodent predation by Turdus leucomelas (Passeriformes: Turdidae).

Pale-breasted Thrush (Turdus leucomelas) is described as an omnivorous bird that forage solitarily or in pairs on the soil. This note reports a rodent predation event by T. leucomelas. The event was recorded on November 14th 2013, in a riparian Forest fragment of Grande River, in Igarapava Municipality, São Paulo, Brazil. Although the presence of small vertebrates on the diet of T. leucomelas is known, this is the first record of a mammal being predated by this bird species. This record is important because it contributes to a better understand of the natural history of Neotropical passerines