Factors of Spatial Distribution and Risk Assessment of Viviparus viviparus L. Invasion in Aquatic Ecosystems of the Ob River Basin

Abstract

Mollusks from the Viviparidae family are one of the invertebrates that actively settle outside their natural habitats. Alien representatives of this family dwell in the waters of North and South America, Europe, and Asia. This paper presents the results of long-term studies of Viviparus viviparus L. unintentionally introduced into the Novosibirsk Reservoir. The effect of types and concentrations of organic substances on the spatial distribution of V. viviparus in the reservoir has been studied. It is found that the formation of denser mollusks settlements (when compared to the natural areal) occurred in the Novosibirsk Reservoir due to its favorable environmental conditions. The Harmonia+ Protocol was used to assess the risk of V. viviparus invasion into water bodies of the Ob River basin, as well as the invasion consequences for its aquatic ecosystems. It is shown that water bodies of the Middle Ob basin are suitable for V. viviparus; the risk of further mollusk spread is estimated as high.