Branta Issues > Issue №6 (2003)

Importance of oxbow lakes for the maintenance of bird diversity in the upper Dniester river basin.

Bokotey AA., Kuchynska I.V., Dziubenko N.V.

General characteristics of the avifauna and population of six main Dniester's oxbow lakes (former riverbeds) are presented in this paper. The material was collected in 1994-2002 in the upper Dniester river basin (Lviv, Ivano-Frankivsk and Ternopil regions).

The avifauna consists of 56 breeding species, among them 38 species are included into the population. The Great Reed Warbler is the dominant; next following species are the Reed Bunting, the Marsh Warbler and the Thrush Nightingale. The species list of separate oxbow lakes includes from 8 to 51 species. Population density ranges within 7.0 - 49.2 pairs/ha and shows strong negative correlation with the oxbow’s size. The species list and the population structure in the individual oxbow lakes are different and depend on many factors: size, age, vegetation, percent of open water, surrounding habitats, recreation load, distance from inhabited localities as well as from the other oxbow lakes. Generally, the oxbows are not of great importance for the avifauna of the upper Dniester basin because of their small number and size, though they noticeably diversify the bird fauna of surrounding habitats. To a certain extent these water bodies are valuable as breeding localities of several rare bird species of regional importance. A colony of the Little Egret is the northernmost point of this species breeding range in Western Ukraine.