Invasion of Zebra Mussel Dreissena polymorpha (Pallas, 1771) in the Basin of Lake Ladoga and the Biochemical Role of the Invader

Abstract—In June 2017, the invasion of an alien species Dreissena polymorpha was recorded in one of the quarries located in the Lake Ladoga basin (the Kelkolovo quarries, Kirovsky district, Leningrad Region). The biology of the population and the trace element composition in shells of the mollusks were studied. It is found that the population is young with a high potential for further development under favorable environmental conditions. One of the prerequisites for invasion of the species into the water body is a high water mineralization, which provides an optimum level of elements necessary for the construction of a calcareous skeleton of a large number of specimens. The main chorological types formed by zebra mussels are brushes and druses which allow the maximum use of food resources in a limited space. The role of shells in accumulation and bio-burial of some trace elements is shown.