4.8 Fishes in Switzerland are endangered
Swiss fish are endangered for a number of reasons: They lack sufficient food because insects and micro-organisms are being killed by environmental toxins. The course of many rivers and streams has been straightened, which reduces the number of available spawning grounds and hiding places such as gravel banks and piles of driftwood. In addition, many fish species travel upriver to breed, yet are unable to do so due to the existence of dams and reservoirs. Climate change is also driving fish species to extinction: in summer, water temperature can reach 30°C, and tens of thousands of fish die of stress and lack of oxygen.
4.9 The sea lamprey
The sea lamprey became extinct in Switzerland in 1884. This migratory fish travels from the sea up into rivers in order to spawn. The construction of hydroelectric power stations prevents them from reaching their breeding grounds. It is interesting to note that the sea lamprey is not actually a fish: this ancient jawless creature uses its sucker-like mouth full of sharp teeth to feed on living fish.
