Features of the Calandra Lark and Corn Bunting spatial distribution and abundance dynamics in the Northern Lower-Volga region were studied in the framework of the «Atlas of breeding birds of European Russia» project. Significant habitat boundary changes to the north (Calandra Lark) and north-east (Corn Bunting) were found over the last 10 - 15 years. Extension limits of the habitat boundaries of both species studied in the European Russia were forecast.