Nearly 12 tons of dead fish removed from Oostende park pond

Oostende's Maria Hendrikapark pond has seen a massive die-off of fish, with nearly 12 tons of dead fish removed by the civil protection on Thursday. Dead fish have also been found in the Gauwlozekreek.

The cause is a combination of the persistent heat and a long dry spell, according to alderwoman Judith Ooms. "This has led to a sharp drop in the water level and a lack of oxygen in the water," she explained. "This oxygen deficit is amplified by the blue-green algae, which are present in large numbers in various parts of the city. They also cause extreme fluctuations in oxygen levels in the water."

In recent weeks, the city intervened in smaller ponds. "When we saw that the fish were in danger, we relocated them," Ooms said. "This is not easy, it is actually recommended to avoid it as much as possible, because moving fish from one pond to another creates new risks. But in places where it was clear the fish were no longer safe, we moved them. That is a last resort; you cannot do that with every pond."

Another measure is aerating the ponds to increase oxygen levels. The Maria Hendrikapark pond already has aerators, but their effectiveness is questionable. "If the water level drops too much, aeration is pointless," Ooms stated. Adding extra water to raise the level was also not an option. "At the moment, after the long dry period, there was no water available anywhere in the region to do that," the alderwoman said.

It is difficult to predict if more fish will die in the coming days. "To be honest, it's a bit of guesswork. We don't know," Ooms admitted. The city will continue to monitor the pond closely. The dead fish are taken to a specialized processing company with which the city has a framework agreement. Earlier this month, hundreds of fish also died in the Vlotdok due to oxygen deficiency.