Ecological and systematic characteristic of wetland birds in the lake Baikal basin

The article presents a systematic and ecological analysis of the structure of wetland bird fauna in the Lake Baikal basin and general patterns of the variability of its landscape and natural areas. 180 species of waterbirds was identified in the Lake Baikal basin, representing about 40% of the region's species diversity. 85% of species composition of the fauna of hydrophilic and hygrophilous birds are represented by Сharadriiformes, Anseriformes, Gruiformes and Ciconiiformes, among them only Charadriiformes account for 47,8%. The systematic composition of different physiographic regions of the lake Baikal basin is differs markedly from the 67 in Khentei-Chikoy highlands to 167 species in the vicinity of lake Baikal and Baikal region. We have traced the general trend to loss of biological diversity of wetland birds in the region from north to south - from the taiga landscape natural zone to the steppe zone, it is determined by the geographical position and specific environmental conditions of the areas. According to distribution, migratory nesting species predominate (49,4%) in the fauna of wetland birds, but vagrants (25,5%) and migratory species (21,7%) migratory species (25,5%) and transitory species (21,7%) constitute a significant proportion. Such a large number of vagrant species is explained by the geographic position of the Lake Baikal basin at the intersection of natural zones and zoogeographic frontiers, as well as by the diversity of ecological conditions. The lake Baikal has a huge attractive force for wetland birds. Many species of birds in different parts of the region have different distribution, and this is associated with the heterogeneity of their ecological conditions. In general, it was found that in the northern areas the proportion of nesting species is higher and the proportion of flying species is less than in the southern regions. Also the proportion of migratory species from north to south is decreasing. According to the biotopic distribution obligate aquatic birds dominates among wetland birds, as well as swamp, wetland meadows and shoals species.