Many species of freshwater mussels are on the verge of local or global extinction. This is why it is important to preserve this species in the Kokemäenjoki River in western Finland.

Many freshwater mussels are on the verge of extinction. Photograph: Sean Gerety/Flickr

Freshwater mussels are one of the most vulnerable taxonomic groups in the world, and many species are on the verge of local or global extinction. Human activities have changed the living conditions of mussels in many ways. This is why Norilsk Nickel Harjavalta Oy is engaged in the conservation of this species in the Kokemäenjoki River in western Finland.

As a result of research carried out in the summer of 2020, scientists found that the number of mussels is recovering.

According to a study report completed at the end of 2020, the prevalence of 0–50 mm long mollusks born after 2014 in the samples was 18%. Also, the quality of the water in the river and the condition of the banks are good, the scientists conclude.

During the survey of the river, four species of mollusks were studied: Unio crassus, Anodonta anatina, Unio tumidus and Unio pictorum.

The results showed a very good recovery of three out of four mussel species. So Anodonta anatina recovered by 229% in six years. At the same time, Unio crassus recovered by 4%. Meanwhile, studying the river bottom, it was noted that in some areas the number of mussels did not change, while in other areas of the river bottom it increased significantly.

The goal of the program is to revitalize freshwater mussels’ populations both in Finland and around the world. Scientists note that the Norilsk Nickel Harjavalta initiative to study mussels in the Kokemäenjoki River in western Finland is extremely useful.

The study of mussels also provides important information about the state of the habitat. The fact that mussels live in the Kokemäenjoki River testifies to effective environmental protection measures in this region, the researchers conclude.

Author