La pêche de la PerchePerca fluviatilis dans les trois lacs subjurassiens (Morat,Neuchâtel et Bienne)

The catch of perch (Perca fluviatilis) taken by professional and sport fishing is studied in three lakes located at the foot of the Swiss Jura mountains (lakes of Morat, Neuchatel and Bienne) where the annual productivity reaches 6 kg/ha. A three year cycle in the catches was induced since fifteen years by fishing pressure. Laws are suggested to improve the situation.