Heatwaves cause fish die-offs in Swiss and German rivers

Extreme heat and rising water temperatures are causing significant fish die-offs in rivers across Switzerland and Germany.

In Villmergen, Switzerland, the Hinterbach stream has almost completely dried up. Local fishing tenant Rudolf Jost reported that the remaining water has become too warm and lacks sufficient oxygen. To prevent further loss, authorities organized an emergency rescue operation using electrofishing to relocate trout to the Erusbach. Despite these efforts, several burbot were found dead in the dry streambed.

Similarly, in the Neckar river near Starzach-Sulzau, Germany, high temperatures exceeding 24 degrees Celsius have led to the deaths of numerous eels and trout. Local fisherman Frank Schmitt noted that heat-induced algae growth further depletes oxygen levels. Eels are particularly vulnerable as they become covered in algae while attempting to burrow into the riverbed. Additionally, warmer waters facilitate the spread of 'red disease,' an infection that can be fatal to eel populations.