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Bird species were surveyed in a variety of habitat types in a lightly populated area of western Brazilian Amazonia. Habitats surveyed were untagged forest, selectively logged forest, ‘capoeira’ (scrub regenerating on cleared land), cropfields, and an isolated 35 ha forest ‘island’. All habitats were within a few kilometres of each other. Many bird species were found to occur in all or most habitats, although the similarlity of the species assemblages dropped with increasing levels of disturbance of the natural vegetation. Certain understorey insectivores common in untagged forest were rarely observed in other habitats; disturbed areas contained higher numbers of flycalching insectivores or birds feeding on both insects and fruit, some of which were open-country rather than forest species. The avifauna of the forest ‘island’ was more similar to that of regenerating scrub than to that of tall forest, and the persistence of forest species was attributed to their ability to move to and from nearby continuous forest areas.

This study documents changes within a community of one nocturnal and five diurnal primate species in response to selective logging of their tropical rain-forest habitat. Groups of two diurnal primate species, Hylobates lar and Presbytis melalophos, were observed in the wild for 14 mo before and 12 mo after the onset oflogging. Both species showed alterations in activity budgets following logging, spending more time resting and less time feeding and travelling. These changes may be attributable to the reduction in the availability of their preferred, more nutritious foods. Both H. lar and P. melalophos were territorial in primary forest in the study area, and there was remarkably little change in their home ranges following logging. Changes that were apparent were generally to conform to changes in habitat topography. The extent of range overlap between P. melalophos groups appeared to increase in older logged forest, however, as food resources changed from an even to a clumped distribution.The overall response of the studied primate community to selective logging appeared to be a reaction to reduced food availability and to fragmentation or other alterations of the habitat. An ability to adjust foraging strategies to cope with variation in habitat and food supply probably accounts for the continued survival of these primate populations in logged forest.

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