The larval mussel is a so-called invasive species that established itself in Lake Mälaren and a number of lakes in Uppland during the 1920s. In 2013, the mussel was found in the Roxen and Glan lakes in Motala Ström's water system. In the same year, an inventory of the larval mussel larvae was made along Göta Canal in Västra Götaland and Östergötland county.

In this project, a new inventory will be made in 2019 with the same performer (University of Borås) and with the same methodology to investigate whether the mussel has spread further in the system. The samples are analyzed microscopically.