A bird community of lowland rainforest in New Guinea. 6. Foraging ecology and community structure of the avifauna

Abstract

The foraging ecology and community structure of 83 co-existing species at Brown River, Papua New Guinea, were analysed. Obligate carnivores, mostly insectivorous, are much more diverse in foraging behaviour than are facultative carnivores. Overlap between insectivorous species may be lower than in similar but depauperate communities in Australian rainforests. Herbivores are separated mostly by differences in weight. Carnivores do not conform to current theory on size-differences between co-existing congeners. It is suggested that the two opposing views, explaining the richness of tropical avifaunas, are both correct. For herbivores the abundance of resources permits wide overlaps between species. For carnivores the complex habitat permits many species to co-exist by finely dividing the habitat.