Hundreds of Fish Die in Ostend Harbor Due to Algae Bloom and Oxygen Depletion

Hundreds of dead fish have been discovered in the Vlotdok in Ostend, Belgium, prompting an urgent response from authorities.

The deceased fish have been identified as flathead grey mullet. Local officials believe a severe lack of oxygen in the water, likely caused by the proliferation of blue-green algae, led to the mass die-off. The algae can create temperature differences in the water during the night, which the mullet are particularly sensitive to, leading to oxygen deprivation.

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It's 1 specific species of sea fish, the flathead grey mullet.

The Civil Protection was deployed to remove the fish carcasses, preventing decomposition and odor. However, port alderman Charlotte Verkeyn warned that more dead fish are expected to surface in the coming days. Signs have been posted around the Vlotdok, urging the public and pet owners to avoid contact with the water due to the potential toxicity of blue-green algae, which can cause skin rashes, eye irritation, and gastrointestinal issues in humans and animals.

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We also explicitly ask people not to go into the water. Keep your dog on a leash too. We have placed signs everywhere to convey that message.