Synanthropization of the adventitious species Dreissena (dreissena) Polymorphain the conditions of anthropogenic transformation of the Bolshoy Irgiz river

The boundary of the range of the D. polymorpha in the Bolshoy Irgiz river has been clarified. The new boundary has expanded to 152 km upstream of the river. Quantity of the species at the stations has been lower than in the Volga reservoirs. Ecological factors determining of distribution and development of the species has been fixed.