Reed warblers (Acrocephalus, Sylviidae) on estuaries in the eastern Sea of Azov basin:: Mechanisms of ecological isolation and habitat changes in the community of high species diversity

Mechanisms of ecological isolation in multispecies communities of reed warblers (Acrocephalus melanopogon, A. agricola, A. scirpaceus, A. arundinaceus, A. palustris, and A. schoenobaenus) were studied on estuaries of the eastern part of the Sea of Azov basin. Two types of communities differing in the composition of breeding species and their relative number were distinguished: communities of the water area of the estuary and flooded vegetation and those of the coastal zone of estuaries. The species-edifiers of the first type of habitat were A. melanopogon and A. arundinaceus; A. schoenobaenus and A. palustris are species inhabiting the land. A. agricola and A. scirpaceus nest both on land and estuaries being a link between these two types of communities. Consequences of anthropogenic changes in the plant cover of flooded areas (substitution of reed for cattail) are discussed.