Monitoring exotic invasive snail species

The presence of the chinese mystery snail (Cipangopaludina chinensis) was first detected in Lake Memphremagog in 2012, followed by the discovery of the banded mystery snail (Viviparous georgianus) in 2019. Memphremagog Conservation's (MCI) team has been monitoring their populations since 2022. The intent is to document their colonization of the Canadian side of the lake and its surroundings. This monitoring was done via snorkeling during the summer season, with data on the characteristics of the habitat (percentage of vegetation and the type of substrate). 

Stations of active research of invasive mystery snails at lake Memphremagog, from 2022 to 2024.

Between 2022 and 2024, a gradual increase of the abundance of the banded mystery snails in Lake Memphremagog was observed. As for the Chinese mystery snail, the population in Austin appears to have increased.
 

The abundance of banded mystery snails in Lake Memphremagog between 2022 and 2024 was much higher than that of the Chinese mystery snails. The banded mystery snail occupied the majority of surveyed sites in Lake Memphremagog, whereas the Chinese mystery snail was confirmed at only one site in Greened Bay in Austin. 

  
Distribution and abundance of banded mystery snail populations (purple) and Chinese mystery snail populations (blue) at lake Memphremagog from 2022 to 2024.  

In 2024, a targeted control operation was conducted on the only known population of Chinese mystery snails, in Greene Bay, in Austin to limit its spread to other areas of the lake. This control collected 1,249 Chinese mystery snails as well as 4,175 banded mystery snails. 

Location of the Chinese mystery snail station in Greene Bay, Austin, 2024.

It would be relevant to continue Chinese mystery snail control measures to limit its spread in lake Memphremagog. 

Want to know more? Consult our studies:  
Suivi des populations de vivipares exotiques au lac Memphrémagog - 2022 à 2024
Suivi des populations des mollusques exotiques au lac Memphrémagog - Été 2023
Suivi des populations de moules zébrées et caractérisation des vivipares exotiques au lac Memphrémagog – Été 2022