The scene looks like an apocalypse. In Enghien-les-Bains, in Val-d'Oise, nearly ten tonnes of inert fish were discovered on the surface of the city's lake. As elsewhere in France, the strong heat of July and August accentuates fish mortality.
"Due to an excessive presence of nitrogen and phosphorus, due to industrial, agricultural and urban discharges, algae proliferate and absorb all the oxygen and therefore there is a death of the whole ecosystem", explains Emma Haziza , hydrologist.
In streams and rivers, the drying up is such that fish get stuck in puddles. Several departmental fishing federations use electric rescue fishing to stun fish and move them to areas where the flow is sufficient.