Estimativas de riqueza, composição de espécies e conservação da avifauna na Estação Ecológica do Panga, Uberlândia, MG, Brasil

Abstract

Generally, time to obtain biological data, as well as human and logistical resources are limiting factors, especially in countries which are underdeveloped and present great diversity. Facing those difficulties, it is essential to develop strategies for fast tracking and inventory of biological diversity, especially when considering the current pace of destruction of natural ecosystems and the high rates of extinction of species. Thus, the objectives of the study are: to assess the composition of bird species in the Panga Ecological Station (EEP), to comment on the conservation of birds and to estimate the variety of bird species by comparing the performance of different types of lists, and the estimators not Mackinnon - parametric associated with it. The study area is located in Uberlândia, State of Minas Gerais, Brazil and represents one of the main units of conservation in the Triângulo Mineiro. The study was conducted between November 2007 and November 2008. The method used in the study was the method of lists of Mackinnon, using lists of 10, 15 and 20 species. To compose the final list of species (n = 234 species) the aspects taken into consideration were the 50 hours of observations made during the calibration of the method in November and December of 2007 and the 250 hours used for the preparation of the lists between January and November 2008 . Besides the number of species found in the field, five non-parametric were estimated using the wealth of estimators: ICE, Chao 2, Jacknife 1, Jacknife 2 and Bootstrap. At the end, the study was made of 308 10-species lists, 201 15-species lists and 149 20- species lists, and 220 species were recorded during the compilation of lists. The wealth field was found in 94% and 96% of average wealth estimated by estimators Jacknife 2 and Jacknife 1, using 10-species lists. Already the estimates generated by estimators ICE, Chao 2 and Bootstrap showed virtually no differences of species observed in the field for all types of lists. However, it is worth emphasizing that the curve of the rarefaction in the area not yet reached asymptote, showing a slight tendency to increase the number of bird species that drive for storage. Already in relative abundance, were produced at different rates of frequency lists between different types of sampling. Here, we recommend the use of this simple technique in environmental impact assessments and offer some suggestions for use of the lists of Mackinnon in areas of Cerrado. Approximately 10% of species recorded (n = 22) are classified as endemic, threatened or migratory, and several other species considered rare or little known region in Minas Gerais. With our results reinforce the importance of Ecological Station of Panga to maintain biodiversity in the Triângulo Mineiro, besides offering information on estimates of wealth can also be used for decision making in conservation in the region and also in rapid environmental assessments. Among the most important records in the area stand out Black Hawk-Eagle Spizaetus tyrannus, Ocellated Crake Micropygia schomburgkii, Forest Elaenia Myiopagis gaimardii, Coal-crested Finch Charitospiza eucosma and Chestnut-bellied Seed-Finch Sporophila angolensis.