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1.
Rev. biol. trop ; 65(4): 1358-1380, Oct.-Dec. 2017. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-897627

ABSTRACT

Abstract The Pantanal wetlands represent one of the largest flood plains in the World, with extreme climatic variations between dry and wet seasons. The area shelters a high diversity of habitats, representing the main formations found in this sub-region: grasslands, savannah, forested savannah, riparian forests, bays and salines, and Negro river itself. This habitat variability determines the structure and dynamics of the bird community, because most species are closely related to specific habitats. For this, we studied the abundance of bird species from 2001 to 2004 in a Pantanal area of Fazenda Rio Negro, Aquidauana, Brazil. The abundance was compared among those four consecutive years, seasons (dry and wet), time of the day (morning and afternoon), and also between seven different habitats, in order to determine the variation in distribution patterns and habitats used by birds. For this, we used the linear transect method in each of the seven habitats, and recorded bird abundances to obtain richness. The richness registered in the mosaic of habitats was of 201 species for the savannah, 87 in forested savannah, 116 in the riparian forest, 75 in grasslands, 120 in bays, 92 in the salines and 64 in the Negro river, accounting for 348 species in the Pantanal of Rio Negro. Overall, 98 species of migratory birds were registered. The results highlighted some important issues regarding the total abundance of birds in Nhecolândia: Psittacidae was the most abundant family in the region, with prominence in all environments. Recurvirostridae, a monospecific family, showed expressive abundance due to the dominance of Himantopusmexicanus in the salinas, followed by Ardeidae, Anatidae and Cracidae. Other families with high abundance were Tyrannidae, Columbidae, Thraupidae and Emberizidae, all in predominantly terrestrial environments. Moreover: a) The highest number of specimens was recorded in the morning period and in the dry season, regardless of the habitat; b) there were no differences in abundance in the same habitat along the years, but the abundance was different among habitats. In general, the results indicated that there is a relatively stable bird population in each habitat along the annual cycle, but there were differences in abundance among habitats. Thus, additional studies on food availability in dry and wet seasons should be better explored in the future, either in this region or in other Pantanal regions. This fact could better explain the seasonal dynamics of the richness and abundance of birds in the Pantanal area in general.


Resumen Los humedales del Pantanal representan una de las mayores llanuras de inundación del mundo, con variaciones climáticas extremas entre las estaciones seca y húmeda. La zona alberga una gran diversidad de hábitats, representando las principales formaciones encontradas en esta subregión de humedales del Pantanal: pastizales, sabanas, sabanas boscosas, bosques ribereños, bahías y salinas, y el propio Río Negro. La variabilidad del hábitat es una parte determinante de la estructura y dinámica de la comunidad de aves, ya que la mayoría de las especies están estrechamente relacionadas con hábitats específicos. Estudiamos la abundancia de especies de aves de 2001 a 2004 en la Fazenda Río Negro, Aquidauana, Brasil. La abundancia se comparó entre los cuatro años consecutivos, las estaciones (seca y húmeda), la hora del día (mañana y tarde) y también entre siete hábitats diferentes, para determinar la variación en los patrones de distribución y hábitats utilizados por las aves. Para ello, se utilizó el método de transectos lineales en cada uno de los siete hábitats, y se registraron las abundancias de aves para obtener la riqueza. La riqueza registrada en el mosaico de hábitats fue de 201 especies para la sabana, 87 sabana boscosa, 116 bosque ribereño, 75 en pastizales, 120 en bahías, 92 en salinas y 64 en el río Negro, con 348 especies en el Pantanal de Río Negro. En total, se registraron 98 especies de aves migratorias. Los resultados destacaron algunas cuestiones importantes con respecto a la abundancia total de aves en Nhecolândia: Psittacidae fue la familia más abundante en la región, con prominencia en todos los ambientes. Recurvirostridae, una familia monoespecífica, mostró abundancia significativa debido a la dominancia de Himantopusmexicanus en las salinas, seguido por Ardeidae, Anatidae y Cracidae. Otras familias con gran abundancia fueron: Tyrannidae, Columbidae, Thraupidae y Emberizidae, todas en ambientes predominantemente terrestres. Además: a) Se registró el mayor número de ejemplares en el período de la mañana y en la estación seca, independientemente del hábitat; B) no hubo diferencias en la abundancia en el mismo hábitat a lo largo de los años, pero la abundancia fue diferente entre los hábitats. En general, los resultados indicaron que hay una población de aves relativamente estable en cada hábitat a lo largo del ciclo anual, pero hubo diferencias en la abundancia entre los hábitats.

2.
Rev. biol. trop ; 65(4): 1569-1581, Oct.-Dec. 2017. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-897643

ABSTRACT

Resumen La expansión del cultivo de palma de aceite ha ocasionado cambios drásticos en los hábitats naturales y modificado la estructura de la vegetación, reduciendo el hábitat disponible para las especies de aves nativas. Se estudiaron las aves asociadas a lotes de palma de aceite de diferentes clases de alturas en el piedemonte de la Orinoquia colombiana, entre agosto 2013 y febrero 2014. Las clases de altura fueron tres: pequeña hasta seis metros, mediana hasta 10 metros y grande hasta15 metros, en cada lote se censaron las aves mediante transectos lineales y se comparó la composición, riqueza, abundancia y describió la estructura de grupos tróficos. Registramos 468 individuos de 44 especies y 23 familias. Gymnomystax mexicanus, Crotophaga ani y Milvago chimachima fueron las especies más abundantes, las dos primeras representan el 4.5 % de las especies abundantes, el 25 % tuvo abundancias intermedias y el 70.4 % fueron especies raras en el área del cultivo. En términos de la abundancia proporcional de especies de aves, las palmas grandes y medianas fueron más parecidas. La comunidad de aves encontrada en parcelas de palma grande tuvo mayor diversidad y uniformidad (2.63 y 0.8907, respectivamente), mientras que en las palmas pequeñas hubo mayor dominancia y abundancia de individuos (0.1825 y 252, respectivamente). En todo el cultivo predominaron aves insectívoras y carnívoras, las cuales tuvieron mayor afinidad por palmas pequeñas y grandes. La palma de aceite puede funcionar como un hábitat favorable para un bajo número de especies de amplia distribución y la altura no parece ser una variable que beneficie de manera significativa la composición, riqueza y abundancia de las especies de aves asociadas a la plantación.


Abstract The expansion of oil palm plantations has caused drastic changes in natural ecosystems and modifications in the vegetation structure, reducing available habitat for native bird species. We studied birds associated with oil palm plantations plots of different palm size classes, in the foothills of the Colombian Orinoquia region, from August 2013 and February 2014. The palm size clases were three: small up to 6 m height; medium up to 10 m; and large up to 15 m; in each plot we counted birds through line transects, and compared their bird composition, richness, and abundance, and described trophic group structure. We recorded a total of 468 individuals, belonging to 44 bird species and 23 families. Gymnomystax mexicanus, Crotophaga ani and Milvago chimachima were the most abundant species, the first tow representing 4.5 % of the abundant species; 25 % had intermediate abundances and 70.4 % were rare in the plantations area. In terms of the abundance of bird species, medium and large palms plots were more similar. Bird community found in plots with large palms had the highest diversity and uniformity (2.63 and 0.8907, respectively), while in those of small palms it was a greater dominance and abundance of individual birds (0.1825 and 252, each one). For the entire plantation, insectivorous and carnivorous birds predominated, and had greater association with small and large palms. Oil palm stands serve as suitable habitats for a small number of widespread bird species, and the height does not seem to be an important factor, that may meaningfully benefit the composition, richness and abundance of bird species associated with the plantations.

3.
Biota neotrop. (Online, Ed. port.) ; 11(3): 275-286, jul.-set. 2011. ilus, graf, tab
Article in Portuguese | LILACS | ID: lil-610577

ABSTRACT

A Zona da Mata Mineira está localizada no sudeste do estado de Minas Gerais, nos domínios da Mata Atlântica, e é uma região altamente fragmentada, com muitas manchas pequenas e isoladas, cuja avifauna é pouco estudada. O objetivo deste trabalho foi inventariar a avifauna da Reserva Biológica Municipal Poço D'Anta (277 ha), uma área de floresta do município de Juiz de Fora, sudeste de Minas Gerais, através da caracterização de alguns aspectos ecológicos e o status de conservação. O levantamento foi realizado entre os períodos de março a setembro de 2007, e março de 2008 a maio de 2009, utilizando a lista de Mackinnon, capturas com redes-de-neblina e observações ocasionais. Foram identificadas 156 espécies, das quais 44 (28 por cento) são endêmicas da Mata Atlântica e seis (3,8 por cento) estão sob algum grau de ameaça. Dentre as espécies ameaçadas, cinco são dependentes de floresta (Dysithamnus stictothorax, Drymophila ochropyga, Sporophila frontalis, Sporophila falcirostris, Cyanoloxia moesta). Em geral a comunidade é caracterizada por aves com sensibilidade média ou baixa a perturbações ambientais. Contudo foram identificadas oito (5,1 por cento) espécies com elevada sensibilidade (Pulsatrix koeniswaldiana, Conopophaga melanops, Sclerurus scansor, Xiphorhynchus fuscus, Lepidocolaptes squamatus, Campylorhamphus falcularius, Anabazenops fuscus e Habia rubica). Além disso, algumas espécies já consideradas extintas em vários outros fragmentos do sudeste do estado estiveram presentes na área. Houve predomínio de espécies insetívoras (39,4 por cento; n = 61) e onívoras (31,6 por cento; n = 49). Como área legalmente protegida e pela sua extensão, considerando as características regionais, a Reserva Biológica Municipal Poço D'Anta tem um papel importante em abrigar populações de aves que vem enfrentando persistentes efeitos antropogênicos na região. A avifauna local está sujeita a impactos tais como atropelamentos, invasões de espécies exóticas e a caça, embora já existam propostas de medidas mitigadoras no plano de manejo da área. Ressalta-se o caráter de urgência em relação à implantação destas medidas a fim de minimizar os impactos sofridos pela avifauna.


The Zona da Mata Mineira is located in the southeastern state of Minas Gerais, Brazil, in the Atlantic Forest domain, and it is a highly fragmented region, with many small and isolated patches, whose avifauna is poorly studied. The objective of this work was to survey the avifauna of the Poço D'Anta Municipal Biological Reserve (277 ha), a forest patch at Juiz de Fora county, southeastern Minas Gerais, determining its ecological traits and conservation status. The survey was conducted between March-September 2007 and March 2008-May 2009 using Mackinnon lists, mist-net captures and occasional observations. We identified 156 species, of which 44 (28 percent) are endemic to the Atlantic Forest and six (3.8 percent) are of conservation concern. Among the threatened species, five are forest dependent (Dysithamnus stictothorax, Drymophila ochropyga, Sporophila frontalis, Sporophila falcirostris, Cyanoloxia moesta). In general the community is characterized by birds with medium to low sensitivity to environmental perturbations. However, eight (5.1 percent) species with high sensitivity (Pulsatrix koeniswaldiana, Conopophaga melanops, Sclerurus scansor, Xiphorhynchus fuscus, Lepidocolaptes squamatus, Campylorhamphus falcularius, Anabazenops fuscus and Habia rubica) were identified. Moreover, some species once considered extinct in several other fragments in southeastern Minas Gerais were still present in the area. Insectivorous (39.4 percent, n = 61) and omnivorous (31.6 percent, n = 49) species were predominant. As a legally protected area and due to its extension, considering the regional characteristics, the Poço D'Anta Municipal Biological Reserve has an important role in harboring populations of birds that has facing persistence anthropogenic effects in the region. The local avifauna is subject to impacts such as running overs, invasions of exotic species and hunting, although there are proposals of mitigation measures in the management plan of the area. It is emphasized the character of urgency regarding the implementation of these measures in order to minimize the impacts suffered by birds.

4.
Biota neotrop. (Online, Ed. port.) ; 10(1): 121-130, Apr. 2010. graf, mapas, tab
Article in Portuguese | LILACS | ID: lil-556903

ABSTRACT

Este trabalho teve por objetivo analisar a comunidade de aves de um remanescente florestal de pequeno porte (10 ha) localizado no município de Tijucas do Sul, estado do Paraná, nos domínios da Floresta com Araucária. Durante o período de novembro de 1999 a abril de 2001 foram realizadas 15 amostragens de dois dias de duração no qual foram utilizados os métodos de amostragem por captura com redes de neblina e observações visuais e auditivas. Foram registradas 118 espécies de 35 famílias. De acordo com a freqüência de ocorrência cerca de 44 por cento das espécies foram consideradas pouco freqüentes. As guildas tróficas mais representativas foram aquelas compostas por espécies onívoras, seguidas pelas insetívoras de folhagem. O método de captura com redes ornitológicas obteve 501 capturas de 47 espécies. As espécies capturadas apresentaram abundâncias relativas variando de 0,31 a 13,16 por cento e o índice de equitabilidade foi de 0,83, demonstrando que a taxocenose apresenta uma baixa dominância. A estrutura da taxocenose registrada é a esperada para um fragmento de pequeno porte, com a maior abundância de guildas e espécies generalistas e com a presença de um grande número de espécies com baixa frequência de ocorrência. Apesar disso, a composição específica com uma grande presença de espécies silvícolas demonstra que o remanescente desempenha um importante papel na manutenção de espécies dependentes dos ambientes florestais.


In this study the community of birds in a small size remnant (10 ha) of Araucária forest, located in the city of Tijucas do Sul, Paraná was evaluated. During the period of November, 1999 to April 2001, 15 surveys had been carried, in which capture with mist nets and visual and aural contacts were used to estimate avian abundance and richness. We recorded 118 species of 35 families. According to the frequency of occurrence around 44 percent of species were considered with low frequency. When analyzed the trophics guilds, omnivorous and insectivorous of foliage were the most representative. By the capture method had been gotten 501 captures of 47 species. The capture species had relative abundances varying from 0.31 to 13.16 percent and the uniformity index was 0.83, demonstrating that the avian assemblage had a low dominance of some species. The structure of avian assemblage registered is expected for a small size remnant, with high relative abundance of generalists species and guilds, and the presence of a high number of species with low frequency of occurrence. Despite of, the specific composition presents a great number of species forest dependents showing that this forest remnant has a important role in the maintenance of species regionally.

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