The Freshwater Pearl Mussel and its habitats in Sweden

Background

The freshwater pearl mussel is a fascinating species that has interested people for centuries. What caught the interest of people at the beginning was its valuable pearls, which led to widespread mussel fishing throughout the country. Today, however, the freshwater pearl mussel is red-listed in Sweden and protected from fishing. The mussel has an exciting biology, with its parasitic stage on brown trout or salmon before it develops into a recognizable mussel. The freshwater pearl mussel lives in fresh, running water with clean bottoms, lots of host fish, and protected edge zones of forest along the water. It is a good indicator of clean, living forest water. The major reasons behind the mussel’s decrease in numbers today include acidification, pollution, inadequate regulation of water flow and forestry.

Today, the freshwater pearl mussel is threatened in several regions of the country, and large parts of Europe. Still, Sweden is a core zone for the mussel, which means that we have an international responsibility for the species’ long-term survival.

The World Wide Fund for Nature, together with seven partners, has now improved the conditions for the freshwater pearl mussel in 21 rivers and streams in southern Sweden. The project was financed to 50% by the EU’s LIFE fund. The Swedish Environmental Protection Agency was co-financier. The seven partners were the County Administrative Boards in the counties of Västmanland, Örebro, Västra Götaland and Kalmar, The National Board of Forestry, the City of Göteborg and Karlstad University.