O uso de habitat pela comunidade de Corujas (Strigidae) em uma Floresta de Terra Firme na Amazônia Central, Brasil

Abstract

Some structural features of environment are relevant for bird’s survivor, such as food availability, nesting places or shelters may influence in the structure of bird communities. The main goal of this study was to describe spatial distribution and the effects of the forest structural components on the habitat use and structure of the owl’s community (Otus watsonii, Lophostrix cristata, Pulsatrix perspicillata, Glaucidium hardyi, Ciccaba huhula, Ciccaba virgata) occurring in a area of “Terra-firme” forest in the central Amazon. From july 2001 to abril 2002, 18 transects of 8 km were surveyed at Reserva Florestal Adopho Ducke of the Instituto Nacional de Pesquisas da Amazônia (INPA) for the population census of 6 owls species. I compared plots of 50 x 50 m, placed where owls were detected. Within the 50 x50 m some components of the Forest were measured (canopy open, abundance of snags, abundance of trees, abundance of woody debris on the ground, the depth of leaf litter, altitude and the distance of closest water bodies) and compared with those in plots that owls are absent which were used as control. L. cristata and G. hardyi showed a pattern of spatial distribuition following the central platô wich divides the Reserve in the middle. O. watsonii, are distributed mainly in the southeast of the reserve while C. virgata, C. huhula and P. perspicillata showed low frequencies (2%). G. hardyi used areas closer to water bodies. Results of multiple regression analyses suggested that areas with a great abundance of snags were also significantly higher in density of L. cristata and O. watsonii. The variation of density of O. watsonii related to areas with a great abundance of trees and areas where the leaf litter was shallow were significantly. The different types of micro-basins, did not effect on the owl’s community composition, which one seemed to be preserved inside the reserve.