Navegando por Assunto "Avifauna"

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Acesso aberto (Open Access)
Análise biogeográfica da avifauna de uma área de transição cerrado-caatinga no Centro-Sul do Piauí, Brasil
(Universidade Federal do Pará, 2001-01-16) SANTOS, Marcos Pérsio Dantas; SILVA, José Maria Cardoso da; http://lattes.cnpq.br/6929517840401044
Acesso aberto (Open Access)
Avifauna do estado de Roraima: biogeografia e conservação
(Universidade Federal do Pará, 2005) SANTOS, Marcos Pérsio Dantas; SILVA, José Maria Cardoso da; http://lattes.cnpq.br/6929517840401044
Acesso aberto (Open Access)
Avifauna do estado do Acre: composição, distribuição geográfica e conservação
(Universidade Federal do Pará, 2009) SILVA, Edson Guilherme da; SILVA, José Maria Cardoso da; http://lattes.cnpq.br/6929517840401044
The Brazilian state of Acre borders Peru and Bolivia, and is located in the lowlands of the southwestern Amazon basin, close to the foothills of the Andes, in a region considered to be biologically megadiverse. Despite this, the region is still relatively poorly‐known in scientific terms, and is considered to be a priority for further biological surveys. With the aim of contributing to the understanding of the bird fauna of southwestern Amazonia, the principal objective of the present study was to evaluate these three questions: (a) How many and which bird species are found in Acre? (b) How are the species distributed in the state? and (c) What is the conservation status of the resident species? These questions were evaluated through a number of different approaches: (a) a comprehensive review of the literature; (b) field surveys over a two‐year period, including the recording and collection of voucher specimens; (c) production of distribution maps for each taxon (including species and subspecies); (d) distribution of the taxa among the state’s three major interfluvia or subregions (east, central, and west); (e) identification of zones of contact and hybridization, based on the distribution of parapatric species within the state; (f) estimation of the potential distribution of the taxa within the state of Acre, based on the extrapolation of the area occupied by that of each ecological unit (phytophysionomy) in which they were recorded; (g) assessment of the conservation goals for each resident taxon; and (h) a gap analysis, based on the overlap of the potential distribution maps with the state’s protected areas. The gap analysis was conducted with reference to three different scenarios: (a) inclusion of all the protected areas; (b) inclusion of only the fully‐protected area exclusive sustainable‐use units and indigenous reservations; and (c) including fully‐protected and sustainable‐use units, but excluding indigenous reservations. The literature review and surveys (historical and current fieldwork) began in August, 2005, and continued until December, 2007. At the end of this period, a total of 7.141 records of birds had been accumulated for the whole of the state of Acre. Of these, 4.623 are of museum specimens, 2.295 (49,6%) of which were collected during the present study. The presence of 655 biological species was confirmed for Acre, distributed among 73 families and 23 orders. One direct result of the study was the addition of five new species to the list of Brazilian birds. Fifty‐nine migratory species were also recorded, including 30 (50,8%) Nearctic and 18 (30,5%) austral migrants, as well as 11 (18,6%) considered to be intratropical migrants. Forty‐four of the species recorded in the study are endemic to the Inambari endemism center. Of the 556 taxa of forest birds resident in Acre, 405 (72,8%) are found in all three subregions, 56 (10,0%) were recorded only in the western subregion, 30 (5.3%) in the eastern subregion, whereas only three (0,5%) were exclusive to the central area. At least six pairs of sister taxa have an allopatric distribution in the state, while 15 sets of taxa present a parapatric distribution. Two zones of secondary contact (east‐west) and two possible hybrid zones (east‐west) were identified within the state. The gap analysis revealed that, under scenario (a), 87,1% of the taxa were fully protected (100% conservation target), and 12% were considered intermediate, that is, partially protected, whereas only 0.8% were completely unprotected. In scenario (b), by contrast, only 0,6% of the taxa were fully protected, 97.6% were partially protected, and 1,8% were totally unprotected. In the third scenario (c), 73,5% of taxa were fully protected, 25,5% partially protected, and only 0,8% completely unprotected. The principal conclusions reached in the present study were: (a) the Brazilian state of Acre has an extremely rich bird fauna, although the number of species recorded should still increase as new surveys are conducted; (b) the Purus and Juruá rivers do not constitute physical barriers to the dispersal of most bird species resident in Acre; (c) the existence of zones of secondary contact not related to the state’s principal river systems supports the conclusion that factors other than physical barriers determine the present‐day pattern of distribution of some of the resident bird taxa in Acre; (d) that the number of “gap” and “partial gap” bird species in Acre is very low when the full protected area network is considered, although this number increases with the exclusion of indigenous reservations, and in particular, sustainable‐use conservation units; and (e) the only species completely unprotected by the state’s conservation network are those restricted to the campina and campinarana ecosystems of western Acre, which indicates a clear need for the establishment of one or more conservation units in this region with the specific aim of protecting this distinct type of ecosystem.
Acesso aberto (Open Access)
Composição e biogeografia da avifauna das ilhas Caviana e Mexiana, foz do Rio Amazonas
(Universidade Federal do Pará, 1994-01-14) HENRIQUES, Luiza Magalli Pinto; OREN, David Conway; http://lattes.cnpq.br/5451507856491990
The islands of Caviana and Mexiana, located in the mouth of the Amazon River, are composed of fluvial sediments and well consolidated lands that date from the Terciary and that were separated from the continent by tectonic action at the beginning of the Holocene. The composition of the avifauna of these islands is analized both from the biogeographical and the ecological points of view. I registered 148 bird species for Caviana Island and 183 for Mexiana Island. The discrepancy between the size of the two islands (Caviana is larger than Mexiana) and the number of species observed is due to undersampling of Caviana. However, the analysis of faunal composition demonstrated that Caviana is richer in forest species than is Mexiana. In contrast, Mexiana showed a greater richness of birds of open habitats. These differences suggest that the rising of sea level at the beginning of the Holocene caused the extinction of greater part of the fauna of the understory ou Mexiana. The portions of Mexiana Island with "teso" vegetation were not submerged, maintaining their characteristic avifauna, which is also represented on Marajó Island. To analyse of the distribuitions of 157 species I subdivided the avifauna into seven categorias: widespread distribution in South America (77 species); widespread Amazonian distribution (25); distribution restricted to eastern Amazonia (7); distribution restricted to south of the Amazon River and east of the Tapajós River (3); distribution restricted to várzea (19); widespread distribution in northern Amazonia and absent from the Tocantins-Xingu interfluvium (5); and widespread distribution in Central Brasil (21). I did not find elements restricted to the Tocantins-Xingu interfluvium. This fact is related to ecological rather than historical factors. The pattern related to northern Amazonia can be interpreted as the result of recent dispersal, the system of islands at the mouth of the Amazon, or by the formation of the Purás and Gurupá Arches, which, associated with the lowering of sea level during Pleistocene, established a connection between lhe right and left banks of the Amazon River. The dispersal occurred in both directions, explaining lhe existence of a large number of species and subspecies with distributions restricted to eastern Amazonia, as well as the dispersal of Central Brasilian elements to north of the Amazon River. This last component of the avifauna is a1so related to the expansion of open vegetations, characteristic of Central Brazil, during glacial periods.
Acesso aberto (Open Access)
Efeito do plantio de dendê sobre a diversidade funcional de aves na Amazônia Oriental
(Universidade Federal do Pará, 2017-03-29) SILVA, Larissa Cardoso; SANTOS, Marcos Pérsio Dantas; http://lattes.cnpq.br/7941154223198901
Oil palm plantations (Elaeis guineenses, Jacq.) are among the fastest growing agricultural practices in the world, and are among the most disturbing in the landscape in tropical regions and are known to affect species diversity. In this sense, we evaluated the functional diversity of birds in 11 points of palm plantation, 11 in permanent preservation areas (APP), which are portions of ciliary forest that includes the margins of water courses with a width of 10m to 30m of each Side of the stream, and 11 in adjacent forest fragments in the eastern Amazon. To evaluate the effect of palm plantations on the functional diversity (DF) of birds, three functional metrics, functional richness (FRic), functional evenness (FEve) and functional divergence (FDiv) were calculated. To test the response of functional characteristics to environmental conditions, we used RLQ ordering analysis. We recorded 269 bird species, 52 species recorded in palm plantations, 158 in APP and 203 in forest fragments. The FRic was lower in palm plantations when compared to APP and forest fragments. However, the APP did not differ from the forest fragments. Functional evenness did not differ between treatments and the functional divergence was shown to be higher in forest fragments compared to APP and palm. However, there was no difference between palm and APP. The RLQ analysis showed a relationship between traces and environmental variables. This decline in functional diversity shows that the loss of forest species has not been offset by the addition of new, disease tolerant species. We emphasize the importance of the maintenance and preservation of forest fragments and riparian forests (APP) in agricultural areas, and that this is a good conservation strategy within highly endangered regions, such as the Eastern Amazon.
Acesso aberto (Open Access)
Estresse oxidativo de aves em clareiras naturais e sub-bosque na região Amazônica
(Universidade Federal do Pará, 2013) GOMES, Andreza de Lourdes Souza; SILVA, José Maria Cardoso da; http://lattes.cnpq.br/6929517840401044
Background: (Oxidative stress of birds in natural gaps and understory sites in the Amazon region). Studies that provide information about the distribution of birds in different phases of forest mosaic are essential for understanding the maintenance of biodiversity, since natural gaps play a central role on the structure and dynamics of tropical forest. Objectives: (a) to determine and compare the abundance and richness of frugivorous birds between the natural gap and understory habitats; (b) verify and associate the abundance of frugivorous birds with the availability of fruits in both areas; (c) to investigate the echophysiological interactions between the oxidative stress and the distribution of specimens of Dixiphia pipra and Willisornis poecilinotus, to determine which factors account for the variance of biomarkers of oxidative stress in these species. Methods: This study was carried out from November 2010 to October 2011 in terra firme forest sites at the National Forest of Caxiuanã, Melgaço, Pará, Brazil. Two different understory forest habitats were selected for sampling on the basis of physiognomies: natural tree fall gap and undisturbed forest. Twelve (12) sites were selected (6 natural gaps and 6 undisturbed continuous forests). In each site, groups of 10 mist nets were set at ground level which remained open from 6:00am to 2:00pm for two consecutive days, totaling six days each month. This procedure lasted for 12 months and the sampling effort totaled 23,040 mist net hours. All specimens captured were identified, marked with metal rings and kept in cotton bags. We collected blood, feces and regurgitation samples to determine the biomarkers of oxidative stress and the composition of the diet. The relationship between thiobarbituric acid reactive substances and the total antioxidant capacity was used as an index of oxidative stress. The vegetation structure was determined based on transects along the mist nets; the plants bearing fruits were identified and the total antioxidant capacity was determined in each plant. Results: During the period of the study 347 specimens of 21 species were sampled. The assemblage of frugivorous birds in natural gap is distinct from that of undisturbed forest sites. The species responsible for dissimilarity were Dixiphia pipra, Pipra rubrocapilla and Turdus albicollis. The richness of birds was similar in both sites, but the availability of fruits and the total capture index were higher in natural gaps. The primary frugivores (those whose feces or regurgitation always showed fruit pulp or seeds) occurred mainly in natural gaps, where the most abundant species was Dixiphia pipra. In addition, Pipra rubrocapilla was the most abundant species in undisturbed sites. Thirty-six (36) species of plants bearing fruits were recorded, and the abundance of frugivorous birds was significantly correlated with the number of plants bearing fruits in natural gaps, where the most common species of plants were: Psychotria colorata and Psychotria iodotricha. On the other hand, Faramea anisocalyx and Virola surinamensis were the most common species in undisturbed sites. The variation of biomarkers of oxidative stress in specimens presenting lek behavior varied with gender and to the site of sampling. In natural gaps, the adult males of Dixiphia pipra showed higher levels of oxidative stress. The high metabolic rate resulting of flight effort to avoid predators, courtship behavior to the female and territory defense, can increase the production of pro-oxidant compounds. However, the ingestion of fruits with high content of antioxidant compounds by male can minimize the deleterious effects of oxidative stress. The variance of oxidative stress of species that do not have organization in leks was associated only with the site of sampling. The specimens sampling in natural gaps showed higher levels of oxidative stress. This can be due to the increase in metabolic rate to avoid predators as well as new flight strategies for foraging.
Acesso aberto (Open Access)
Filogeografia comparada de aves com distribuição trans-amazônica e trans-andina
(Universidade Federal do Pará, 2015-05-28) MIRANDA, Leonardo de Sousa; ALEIXO, Alexandre Luis Padovan; http://lattes.cnpq.br/3661799396744570
Acesso aberto (Open Access)
Padrão de distribuição de assembléias de aves nas florestas de várzea do rio Madeira
(Universidade Federal do Pará, 2014) SILVA, Bianca Darski; SANTOS, Marcos Pérsio Dantas; http://lattes.cnpq.br/7941154223198901
Acesso aberto (Open Access)
Padrões de distribuição da avifauna em área de Ecótono Cerrado-Caatinga no Nordeste do Brasil
(Universidade Federal do Pará, 2015) GONÇALVES, Gabriela Silva Ribeiro; OLIVEIRA, Arthur Ângelo Bispo de; http://lattes.cnpq.br/1100433822757573; SANTOS, Marcos Pérsio Dantas; http://lattes.cnpq.br/7941154223198901
Acesso aberto (Open Access)
Padrões espaciais em comunidades de aves amazônicas
(Universidade Federal do Pará, 2006) VALENTE, Renata de Melo; SILVA, José Maria Cardoso da; http://lattes.cnpq.br/6929517840401044
Amazonia houses the world´s richest avifauna. To understand the processes that originated and have maintained this diversity, are required detailed studies concerning spatial variation of major patterns of bird assemblages as well as comparisons among them across different spatial scales. In addition, it is essential to use an approach that takes in to consideration different factors that can be acting on and influencing these patterns. This thesis is composed of three chapters. In the first chapter, the composition, ecological characteristics and vulnerability patterns of the avifauna at the Ferreira Penna Scientific Station (ECFPn), Eastern Amazonia, are described. An updated species list to that area, with information on the abundance, trophic guilds and habitat type is presented. Vulnerability for each species was determined by using rarity patterns. In the second chapter, the avifauna of ECFPn is compared with other sites representing the different areas of Amazonian bird endemism. Different taxonomic and ecological categories were considered in several comparisons to evaluate if patterns of distribution are different among these categories and determine which factors can influence the patterns observed. Finally, the third chapter presents an analysis of the spatial variation of richness, abundance and similarity across six 100-ha sites located within a homogeneous landscape dominated by upland forests. Variation in species composition was then correlated with geographical distance and vegetation structure of these sites. The combination of theses studies increases our knowledge about the area of endemism Xingu and uses for the first time several different approaches to investigate distribution patterns bird assemblage in Amazonia at different spatial scales.