Biodiversity of forest ornithofauna in Russian Priishimje

Based on field research conducted in 2015 and 2016, the structure and diversity of bird communities in forest habitats of the Russian Priishimje has been analysed. When considering the average number of species in the ecotone habitats and population density of birds, it was found that sub-taiga subzones have the lowest values among all the investigated natural areas. Considering the distribution of Shannon and Simpson diversity indexes in habitats, it was established that the indexes decreased significantly in habitats of the forest-steppe zone (birch forests) in 2016 as compared to 2015 and there was an increase of these indexes in the habitats of sub-taiga subzones. It is suggested that loss of species diversity was due to the reduction of low-numbered species and because of common species conservation in 2015. The situation is different in sub-taiga, i.e. while common species have been preserved; the variety of low-numbered species has increased. When comparing the diversity index by months, a link was established between the indicators of average monthly temperatures and the abundance of birds. That leads to the reduction of surface area, the impoverishment of the species composition of forest vegetation and distribution of open and semi-open habitats which are more typical for southern areas.