FURB – UNIVERSIDADE REGIONAL DE BLUMENAU - SBO

XII CBO – Congresso Brasileiro de Ornitologia
21 a 26 de novembro de 2004
Universidade Regional de Blumenau/SC
EFFECTS OF FOREST ENVIROMENTAL HETEROGENEITY ON
COMMUNITY COMPOSITION OF OWLS (AVES: STRIGIDAE) IN CENTRAL
AMAZON.
Obed Garcia Barros 1 , e Renato Cintra 1
1 Instituto Nacional de Pesquisas da Amazônia - INPA. Caixa postal 478 CEP 69011-970,
Manaus, Amazonas.
The goal of this study was to compare top predator (owls) community composition
among five drainage water basins, and analyze the effects of forest environmental
heterogeneity, produced by some structure components, on owl's occurrence, abundance
and community composition. The study was done in Terra-Firme forest at Reserva
Ducke (02º55’,03º01’S; 59º53’,59º59’W), Central Amazon. We surveyed the owls from
July 2001 to April 2002 in eighteen 8 km transects within the Reserve. We placed 50 x
50 m plots where owls were detected and similar plots of the where the owls were
absent. Within the plots six components of the forest structure were recorded. We
recorded the following six species, Otus watsonii, Lophostrix cristata, Pulsatrix
perspicillata, Glaucidium hardyi, Ciccaba huhula, Ciccaba virgata. Results of multiple
regression analyzes indicates that the abundance of owls (considering all species
together) increased significantly with increasing in the abundance of snags, and with
decreasing abundance of forest logs. We used Multivariate analysis (MDS ordination
techniques) to compare owl's community composition and found out that it was
significantly different among the drainage water basins. Also there was a positive and
significantly relationship between abundance of snags and the owls community
composition. The results indicate that nocturnal top predators (owls) in neotropical
rainforests can be affected by forest environmental heterogeneity.
Keywords: Owls, drainage water basins, forest structure components
Financed by: INPA, CNPq – PNOPg / PELD
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