Species richness, habitat use and conservation of birds of Alor Island, Lesser Sundas, Indonesia

Abstract

In the Lesser Sundas, rainforest is a key habitat for endemic and threatened birds but avian community patterns on Alor Island, Indonesia, have never been examined. In May 2002, systematic observations were made in two major habitat types in Tanglapui Timur village lands to describe comparative patterns of habitat use and bird species-richness and to identify populations of restricted-range bird species. There were substantial differences in avifaunal composition between rainforest and Eucalyptus savanna, although ordination of bird species by plots revealed a continuum. Bird species-richness did not differ significantly between habitats, but the following species groups were strongly associated with rainforest: globally restricted-range species, forest-specialists, Oriental and Australo-Papuan species and frugivores. This result was associated with substantial structural differences, including greater canopy cover and canopy height in rainforest. Three species were recorded significantly more frequently in Eucalyptus savanna (Brown Honeyeater, Lichmera indistincta; Golden-bellied Gerygone, Gerygone sulphurea; and Pied Bushchat, Saxicola coprata). All six restricted-range species known from Alor were recorded, indicating the importance of the study site for conservation. Study is needed of the taxonomic relations of Alor populations of Lesser Shortwing (Brachypteryx leucophrys) and Yellow-breasted Warbler (Seicercus montis).