Аннотация:BIRD COMMUNITIES OF LOWLAND AND MONTANE FORESTS
IN SOUTHERN VIETNAM: SPECIES COMPOSITION
AND TROPHIC GUILDS DISTRIBUTION
Bird communities were studied during field surveys in five protected forested
territories in the south of Vietnam: Yok Don National Park, Dong Nai Biosphere
Reserve, Bu Gia Map National Park, Bidoup-Nui Ba National Park and Chu Yang Sin
National Park. Lowland communities showed higher species diversity than montane
ones. The similarity measure of bird species composition was rather high among three
lowland forests and between two montane forests, however, few species were common
for both lowland and montane communities. The study of the ecological structure of
bird communities was based on trophic guilds composition. Six guilds of forest birds
were conventionally defined: insectivore, predatory, frugivore, nectarivore, granivore
and omnivore. All guilds were presented in all studied bird communities, but their
portion varied between lowland and montane forests. The high similarities of guild
proportions between all lowland and both montane forests demonstrated, assumingly,
that the found ecological structures are stable for each type of community. Although species composition of trophic guilds varied greatly between lowland and montane
communities, the similarity measure was greater among predatory birds and less among
“plant-eating” birds (frugivore, nectarivore and granivore guilds combined). Apparently,
that reflects greater dependence of “plant-eating” birds upon plant species composition
in lowland and montane forests. The complex assessment of bird communities based on
species composition and ecological structure can be useful for comparative studies of
bird distribution in diverse ecosystems and for temporal monitoring of degrading or
restored natural habits.