Аннотация:Cis-Caucasia steppes of Southern Russia were actively afforested throughout the 20th century. The result of such a deep anthropogenic change is the emergences of a unique zone within the conditions contribute to resettlement of different taxa of birds towards each other from the European deciduous forest and the Caucasus forests to the north and south respectively. Our study focuses on the abundance, distribution and interaction between two closely related species of nightingales, the Common Nightingale Luscinia megarhynchos and the Thrush Nightingale Luscinia luscinia in Cis-Caucasia steppes of Southern Russia. Analysed data were gathered during 2017, 2019 and 2021 in Cis-Caucasia steppes. The songs of males were recorded, ecologically important traits were measured and a blood sample was collected for genetic analysis. The zone of secondary contact of nightingales in the Cis-Caucasia steppes was located in the north-eastern part of the Krasnodar region and in the western part of the Republic of Kalmykia according to study of this region conducted 40 years ago. At present, mixed populations have been found only in the Kalmykia. In the investigated areas of the Krasnodar region, the Common Nightingale was not found in the survey, although it was common in this area. The number of the Thrush Nightingale, on the contrary, has increased and the obtained data shows spreading the species to the south. These results characterize the Cis-Caucasia zone of repeated contact of nightingales as a sufficiently dynamic area, the reason of which is probably the fact that the origin is relatively young and anthropogenic.