Clean-up operation of dead fish in Dyje river begins

Firefighters in Břeclav are helping fishermen with a huge clean-up operation to clear the tens of tons of fish that died of suffocation in the river Dyje in South Moravia during the last week. The Czech News Agency reports that only about a tenth of the total amount of fish has been cleared so far, corresponding to around nine tons, according to Zdeněk Blabla, chairman of the Moravian Fishermen's Association.

The death of the fish is due to a lack of oxygen caused by an overabundance of cyanobacteria. Cyanobacteria consume oxygen at night and tend to multiply when there is hot weather, low water levels and a higher than normal concentration of phosphorus, which is the main nutrient the bacteria require. Phosphorus usually enters rivers because water treatment plants do not adequately remove it during the cleaning process, according to Petr Chmelař, spokesman for the Moravian River Basin.

The dead fish are being taken to a rendering plant to be processed. Among them are carp, zander, catfish, and bream. Fishermen estimate the damage caused to be in the millions of crowns.