Community-level effects of a Viviparus viviparus L. (Gastropoda, Viviparidae) invasion in the Novosibirsk reservoir

摘要

Alien species can have significant impacts on invaded ecosystems that include but are not limited to the reduction in biodiversity and alteration of the structure and functioning of ecosystems. From a management perspective, it is critical to assess the impact of alien species on the native community. The river snail, Viviparus viviparus L., is the most numerous invasive species in the Ob River basin. For 10?years from 2008 to 2017, the distribution of the alien species, V. viviparus, was studied in the Novosibirsk reservoir. During this period it colonized a large area, spreading throughout the middle and lower part of the reservoir. The average rate of mollusk dispersion exceeded 10?km per year, indicating potential facilitation by anthropogenic vectors such as recreational boating and fishery. In some parts of the reservoir, V. viviparus formed large aggregations with a biomass up to 4385?g/m2. Lower species diversity, but higher density and biomass of soft zoobenthos occurred in areas with high densities of V. viviparus.