Results and perspectives of fish population studies in the central lake-river system of the Meschera lowland

The study presents results of studies of fish fauna inhabiting the central lake-river system of the Meschera lowland. It includes the following structural elements: river Buzha, Klepiki (Great) lakes, river Pra, supplementary system of river Pra (tributaries, channels, inlets, oxbows and lakes), watershed lakes of river Pra’s high floodplain, lakes of River Oka and river Pra combined floodplain. Studied lake-river system is characteristic of having a high share of phytophilous fish species with long and average life cycle duration – bream, zope, ide, silver bream and pike. Optimal conditions of their reproduction are present in the river Pra’s supplementary system, especially in the inlets, oxbows and lakes of average size as well as in lakes of River Oka and river Pra combined floodplain. We suggest that the shallow Klepiki lakes and, possibly, river Buzha play an important role in the reproduction of these species. However, there is few data on the last two elements of the lake-river system. The studied part of Meschera lake-river system is notable for high fecundity of fish inhabiting it. Under favorable climatic conditions and the absence of anthropogenic press (poaching) present structure of fish fauna with high abundance of phytophilous fish species with long and average life cycle duration is likely to remain in a stable state