The structure of summer bird's associations anthropogenic ecosystems steppe landscapes Baikal Siberia

The objective of the article is a revealing features of ecology-systematical structure of summer population of birds in anthropogenic ecosystems steppe landscapes Baikal Siberia - fields, fallow lands and settlements. In spring-summer period 33 species, on wild grasses fallow lands - 36 species were noticed. All species on the fields are visitors, we noticed very rare nesting two species (Eurasian skylark (Alauda arvensis) and Richard's pipit (ANTHUS richardi) on the oat field). On wild grasses fallow fields 6 species are nesting, others are visitors. The bird's density in agrocenoses is very low with bad ecological conditions. Bird's population of settlements in steppe landscapes of Baikal Siberia relatively rich and diverse in specific and ecological attitude. 26 species are registered include 16 nesting species. The basis of synanthropic associations constitute typical for South Siberia species (pigeons, some species of Corvidae, sparrows and etc.). The regional specificity to bird's population of settlements in steppe makes nesting of some species like a Rock sparrow, Daur- ian redstart. It has been established the influence of natural biotopes around the settlements on their fauna structure especially on diversity of visitors. Small geographical differences in structure of bird's population different regions Baikal Siberia are discovered.