The Fens in Franches-Montagnes
10 December 2021
The Parc Du Doubs in the Franches-Montagnes (canton of Jura) is known for the many streams, rivers and fens, a heritage of the last ice age and melting water, about 10 000 years ago.
The fens of Les Royes and Gruère are the best known and the largest. One smaller fen is l’étang de Bollement. The surface is about 1 ha; the nature reserve is 7.5 ha.
The fauna in the immediate vicinity shows remarkable diversity. The presence of the flowing water of the stream and the stagnant water of the fen, and the peat soil are the origin of this rich biodiversity.
The mills and sawmills also played an important economic role in Bollement from the 16th to the 20th century. This was also the case for the fens of Des Royes and Gruère.
It is hard to imagine today that such quiet, beautiful natural areas still had a lot of economic activity a century ago. It also shows how quickly nature can recover.