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, 85 are migratory and 33 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 of the region of the Volta Grande Hydroelectric Power Plant in Southeast Brazil

Abstract 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, 85 are migratory and 33 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 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, 85 are migratory and 33 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.(AU)

Do different sampling designs produce differences in the metrics of curimba, Prochilodus lineatus (Characiformes: Prochilodontidae)?

Probabilistic sampling, a classical recommendation for unbiased data, has been often overlooked. Fish sampling in reservoirs, unlike most rivers, can be accomplished by a variety of probabilistic sampling designs due to few restrictions in the choice of sampling sites (SSs). We evaluated whether population metrics of Prochilodus lineatus differ between fixed SSs (do not change with each sampling trip) and variable SSs (change with each sampling trip) in the Volta Grande (VGR) and Jaguara (JR) reservoirs of the Grande River, Paraná River basin, Brazil. We used gillnets to sample fish at nine probabilistic fixed SSs and nine probabilistic variable SSs per sampling trip. We conducted 25 sampling trips in VGR and 22 in JR during 2011 to 2015, and performed 35 analyses of 8 metrics for each reservoir. We found sampling design influenced only 7% of the analyses involving three metrics, apparently caused by biased data of fixed SSs. We attribute the small percentage of analyses influenced by sampling design to the low spatial heterogeneity of the reservoirs. The choice of the most appropriate sampling design seems to depend on the type of variation (temporal or spatial) that one wishes to detect, and the availability of time and financial resources.(AU)

A amostragem probabilística, uma recomendação clássica para dados não enviesados, tem sido frequentemente negligenciada. Reservatórios, diferentemente da maioria dos rios, permitem diversos desenhos amostrais probabilísticos para a amostragem de peixes por impor poucas restrições na escolha de pontos de coletas. Neste trabalho, avaliamos se métricas populacionais do Prochilodus lineatus diferem entre amostras de pontos fixos (não mudam a cada campanha) ou variáveis (mudam a cada campanha) nos reservatórios de Volta Grande (VGR) e Jaguara (JR), rio Grande, bacia do alto rio Paraná, Brasil. Amostramos os peixes com redes de emalhar em nove pontos fixos e nove pontos variáveis por campanha, todos probabilísticos. Foram 25 campanhas em RVG e 22 em RJ de 2011 a 2015. Para cada reservatório, fizemos 35 análises para 8 métricas. Encontramos influência do desenho amostral em apenas 7% das análises e em três métricas, aparentemente provocada por dados enviesados dos pontos fixos. Atribuímos a pequena porcentagem de análises influenciada pelo desenho amostral à baixa heterogeneidade espacial dos reservatórios. A escolha do desenho amostral mais apropriado parece depender, além disso, do tipo de variação (temporal ou espacial) que se deseja detectar, e a disponibilidade de tempo e de recurso financeiro.(AU)

Do different sampling designs produce differences in the metrics of curimba, Prochilodus lineatus (Characiformes: Prochilodontidae)?

Probabilistic sampling, a classical recommendation for unbiased data, has been often overlooked. Fish sampling in reservoirs, unlike most rivers, can be accomplished by a variety of probabilistic sampling designs due to few restrictions in the choice of sampling sites (SSs). We evaluated whether population metrics of Prochilodus lineatus differ between fixed SSs (do not change with each sampling trip) and variable SSs (change with each sampling trip) in the Volta Grande (VGR) and Jaguara (JR) reservoirs of the Grande River, Paraná River basin, Brazil. We used gillnets to sample fish at nine probabilistic fixed SSs and nine probabilistic variable SSs per sampling trip. We conducted 25 sampling trips in VGR and 22 in JR during 2011 to 2015, and performed 35 analyses of 8 metrics for each reservoir. We found sampling design influenced only 7% of the analyses involving three metrics, apparently caused by biased data of fixed SSs. We attribute the small percentage of analyses influenced by sampling design to the low spatial heterogeneity of the reservoirs. The choice of the most appropriate sampling design seems to depend on the type of variation (temporal or spatial) that one wishes to detect, and the availability of time and financial resources.(AU)

A amostragem probabilística, uma recomendação clássica para dados não enviesados, tem sido frequentemente negligenciada. Reservatórios, diferentemente da maioria dos rios, permitem diversos desenhos amostrais probabilísticos para a amostragem de peixes por impor poucas restrições na escolha de pontos de coletas. Neste trabalho, avaliamos se métricas populacionais do Prochilodus lineatus diferem entre amostras de pontos fixos (não mudam a cada campanha) ou variáveis (mudam a cada campanha) nos reservatórios de Volta Grande (VGR) e Jaguara (JR), rio Grande, bacia do alto rio Paraná, Brasil. Amostramos os peixes com redes de emalhar em nove pontos fixos e nove pontos variáveis por campanha, todos probabilísticos. Foram 25 campanhas em RVG e 22 em RJ de 2011 a 2015. Para cada reservatório, fizemos 35 análises para 8 métricas. Encontramos influência do desenho amostral em apenas 7% das análises e em três métricas, aparentemente provocada por dados enviesados dos pontos fixos. Atribuímos a pequena porcentagem de análises influenciada pelo desenho amostral à baixa heterogeneidade espacial dos reservatórios. A escolha do desenho amostral mais apropriado parece depender, além disso, do tipo de variação (temporal ou espacial) que se deseja detectar, e a disponibilidade de tempo e de recurso financeiro.(AU)

Reproduction of Oligosarcus hepsetus (Cuvier, 1829) (Characiforms) in the Serra do Mar State Park, São Paulo, Brazil

The purpose of this study was to characterize the reproduction of Oligosarcus hepsetus in the Grande river (Santa Virginia Unit - Serra do Mar State Park) based on the reproductive period, length of first gonadal maturation for both sexes, sexual proportion, oocyte development, type of spawn and fecundity. The Grande river was sampled monthly from January through December 2004. The numerical frequency of the stages of maturity and the volumetric method were utilized to determine the reproductive period and fecundity, respectively. The reproduction of Oligosarcus hepsetus was characterized by a long period, relatively low fecundity, precocious length of first gonadal maturation and parceled spawning.

O objetivo foi caracterizar a reprodução de Oligosarcus hepsetus no rio Grande (Núcleo Santa Virgínia - Parque Estadual da Serra do Mar). Foram abordados o período reprodutivo, os comprimentos de primeira maturação gonadal para ambos os sexos, a proporção sexual, o desenvolvimento ovocitário, o tipo de desova e a fecundidade. O rio Grande foi amostrado mensalmente de janeiro a dezembro de 2004. A freqüência numérica dos estádios de maturidade e o método volumétrico foram utilizados para a determinação do período reprodutivo e da fecundidade, respectivamente. A reprodução de Oligosarcus hepsetus foi caracterizada por ter período longo, fecundidade relativamente baixa, comprimento de primeira maturação gonadal precoce e desova parcelada.