Heat waves cause fish to die in mass in Switzerland

The river water temperature rises due to the hot sun causing many cold-water freshwater fish to die on the mass in Switzerland.

Dead fish were collected on the Rhine on August 6.(Photo: Reuters).

Prolonged heat waves in Europe in the past days caused many freshwater fish species on the Rhine River in Switzerland to die mass, AFP reported yesterday. The most severely affected area is the passage from Lake Constance to the Rhine Falls, where thousands of fish are dead or moved to colder waters to avoid heat.

The hot sun has pushed the river water temperature to above 27 ° C, the temperature is too high compared to cold-loving fish such as salmon and Thymallus - a freshwater fish of the Salmon family. According to Andreas Vogel, an official in Schaffhausen state, northern Switzerland, about 1,000kg of dead fish has been collected since last weekend on the Rhine River, accounting for 1/4 - 1/3 of the annual fish catch in this area.

In 2003, Switzerland also experienced an unusually prolonged heatwave that caused 90% of Thymallus fish to be wiped out. The Swiss government is "doing everything possible" to save the situation, including moving fish to cold waters hundreds of kilometers away and actively collecting fish bodies so as not to pollute the water. However, the number of dead fish is expected to continue to increase in the next few days due to the hot sun.