Botulism
Botulism occurs mainly during warm periods in stagnant or slow-moving water, such as ponds and ditches. The disease can lead to mortality among ducks, other waterfowl, and fish. Therefore, it is important to report dead or sick animals promptly to prevent further spread as much as possible.
We've compiled a list of frequently asked questions and answers for you.
What is botulism?
Botulism is a disease caused by a toxin produced by the bacterium Clostridium botulinum. Waterfowl and fish are particularly susceptible to this toxin. The bacterium occurs naturally in the environment and can multiply rapidly under warm, oxygen-deprived conditions, such as in the carcasses of dead animals. This process releases the toxin.
Animals can become infected by ingesting this toxin. This causes symptoms of paralysis and can lead to death. Dead animals then become a new source of infection. That is why it is important that carcasses be removed quickly.
Is botulism dangerous to humans?
Outbreaks in surface waters in Limburg almost always involve type C botulism. This type is not known to be dangerous to humans. However, the advice is not to touch dead animals and to avoid contact with water containing large numbers of sick or dead animals.
Botulism in humans is very rare in the Netherlands and is usually caused by contaminated food, not by contact with surface water.
Is botulism dangerous for pets?
Dogs and cats are much less susceptible to botulism than waterfowl and fish. However, they can still become ill. Therefore, it is advisable not to let pets drink from or swim in water where botulism may be present.
How can you recognize botulism?
Sick waterfowl often exhibit signs of paralysis. They can no longer hold their heads or necks upright, have difficulty moving, or are unable to fly. Fish may also become sluggish or have trouble swimming.
What should I do if I see a dead duck or fish?
- Do not touch or move the animal.
- Keep pets away.
- Please report dead or sick waterfowl to the Limburg Water Board by calling (0800) 0341 24 (toll-free, available 24 hours a day).
- Report live, sick waterfowl to the Animal Ambulance at (0495) 794 549
Is it okay to swim or fish in water where there are dead animals?
If botulism is suspected or if there are dead animals in the water, swimming and fishing are not recommended. It is also advised not to let pets swim in the water or drink from it.
What can we do to prevent botulism?
Botulism is a natural phenomenon that cannot be completely prevented. However, its spread can be limited by promptly reporting dead animals and having them removed. This reduces the likelihood that other animals will become infected.
Where can I find more information?
For more information, visit the Limburg Water Board's website: