Huge amounts of dead fish have been found in a reservoir in Poland near the Oder River, where wildlife was devastated by toxic algae in the summer of 2022.
More than 14.5 tons of fish was recovered in recent days in the Dzierzno Duże reservoir, which branches off from the Gliwice Canal connecting to the river, Marek Wójcik, head of the Silesian regional administration, said on Friday.
Laboratory tests by environmental authorities had found a high concentration of golden algae in water samples from the reservoir, the official said.
Barriers had been installed in a connection between the reservoir and the Gliwice Canal to prevent golden algae and infected fish from entering the canal and from there into the Oder.
Dead fish will continue to be recovered from reservoirs in the coming days, Wójcik added.
In late July 2022, a mass die-off of fish occurred in the Oder, which forms part of the border between Germany and Poland.
Experts in both countries concluded that a toxic bloom of the poisonous Prymnesium parvum algae likely caused the phenomenon.
The Gliwice Canal, which was commissioned in 1939, is 41 kilometres long and connects the Upper Silesian city of Gliwice with the Oder.
A large amount of dead fish was also recovered there last summer, after which local authorities ordered the water to be enriched with oxygen.
