During the 20th century this species saw a dramatic decline in numerousness of individuals and occurrence localities.

The pearl mussel has a complicated life cycle. In the first phase of evolution it parasites on the gills of a salmonid fish, in the second phase it lives buried in the bottom of a water body.

The third, longest life period is then spent on the bottom surface, and the animal is half-inserted into the substrate. It is a longeval creature which may live more than 100 years.

The pearl mussel is confined to very clean oligotrophic water bodies. It has great demands not only on water quality, but also on the nature of the bottom, as well as on the composition of the vegetation cover of a catchment area.

Surrounding terrestrial plant vegetation is the main source of food for the pearl mussel, consisting of microscopic particles of a half-decomposed vegetable matter.

The complicated interlinking of the pearl mussel's life with many components of its environment, together with changes in water bodies taking place especially since the 19th century, has resulted in a disconsolate situation of the pearl mussel populations not only in the Czech Republic, but also in Europe.

In the CR there are currently known merely 15 occurrence localities, one of them being the most important one in Central Europe.

In order to preserve the pearl mussel, the CR has adopted a preservation program aimed at rehabilitating ecologically balanced oligotrophic water bodies, where the pearl mussel would be able to exist permanently.

Information & Contact:

Mgr. Michal Bílý
VUV.TGM Praha
Podbabská 30
160 02 Praha 6
tel: 00420 220 197 265
fax: 00420 233 333 804