Reporting dead animals

If you find a dead fish or bird, please report this as quickly as possible to the ‘Meldpunt Toezicht’ at the Hoogheemraadschap van Delfland (Delfland Water Board). You can reach this service 24 hours a day at tel. 015-270 18 88.

You can also send an email to: Make sure you report the date, time of day, the location, number of dead animals and kind of animal. The Water Board will work together with the municipality to remove the animals quickly and professionally.

In the summer of 2009 a number of dead fish and waterfowl were found in different areas in the Wateringse Veld neighbourhood. Studies have shown that several of these animals were infected with botulism, a form of food poisoning, prevalent mainly in waterfowl and mainly occurring in the summer when the water warms up.


Botulism is caused by the bacterium Clostridium botulinum which makes the botulinum toxin. The toxin paralyses the birds’ muscles, leading them to suffocate or drown. Botulism often occurs when temperatures rise above 20 degrees Celsius and in a high-protein environment. Shallow waters quickly become warm and are the ideal breeding ground. Dead animals lying in the water provide a breeding ground for the bacterium.

The illness spreads when fish and birds ingest the dead animals along with the toxin. That’s why it is important that the dead animals are removed as quickly as possible from the water.

Sick animals

Birds infected with botulism stand a good chance of survival if they are treated quickly at a bird rescue. If you see a sick bird, please contact the Animal Rescue Service at tel. 070-328 28 28 (24 hours a day). Infected birds are slow, are unable to fly or can only fly a little bit and have difficulty walking. They swim with a stretched neck and let their heads hang in the water because their neck muscles are weak. The birds lie deep in the water and have droopy wings.

Do not touch infected animals with your bare hands but use a plastic bag, for example. Avoid contact with the water in which the animals are lying.

Weekly checks

Botulism unfortunately cannot be prevented. The Delfland Water Board and the Municipality of The Hague will take measures to combat the illness as much as possible. They conduct weekly checks of all waterways and remove dead animals immediately. The water quality is also watched over carefully.

More information can be found at or

Published: 11 April 2017Modified: 12 May 2017