Station 2 - English

Brooks Black with Pearl Mussels Station

The last pearls of the Eifel

The freshwater pearl mussel owes its name to its ability to enclose foreign objects that have penetrated inside its shell with mother-of-pearl, as a protection from injury, thus forming pearls up to five millimetres in diameter. Previously, millions of pearl mussels made their home in the upper and middle reaches of various bodies of water in the Eifel. Due to its immense wealth of pearl mussels the Schwalm, which flows into the Rur river near Monschau, received a new name: Perlenbach (Pearl brook).

In the 1880s, factory owner Josef Dahmen still transported mussels from the Schwalm by the cartload to his “pearl factory” in Monschau. In 1900 the Eifel pearl fishery finally collapsed. One hundred years later, only two dozen freshwater pearl mussels were to be found in the entire Perlenbach.

The dramatic decline was caused not only by the pearl fishery but also, much more importantly, by the pollution and destruction of the water biotopes. Today renaturalisation measures for National Park waters can create the conditions required for the freshwater pearl mussel to make its home here again.


On the right next to the bar code is a model of an opened freshwater pearl mussel that you can touch.

The freshwater pearl mussel is the only European freshwater mussel that forms valuable pearls. However, only one in approximately 2000 mussels contains a pearl. To this day, such pearls adorn church ornaments and royal crowns, and are regarded as precious jewels.