Blue-green algae: a serious danger to dogs at the lake

Blue-green algae are actually cyanobacteria. Some species produce strong liver or neurotoxins that can be dangerous for dogs after drinking contaminated water. This is how you recognise warning signals and act correctly in an emergency.

A warm summer day at the lake is the greatest thing for many dogs. But greenish streaks, foam or deposits on the bank can indicate a bloom of cyanobacteria. They are colloquially called blue-green algae, although they are not algae but bacteria.

Not every cyanobacterial bloom produces toxins. However, it cannot be reliably determined from the outside whether and how toxic the water is. Dogs are particularly at risk because they swallow water while swimming, drink from the bank or later lick their wet fur.

Certain cyanobacteria produce cyanotoxins. These include substances that primarily damage the liver and others that attack the nervous system. The concentration can increase significantly locally on the shore due to wind. This is exactly where dogs often drink and play.

Dead, dried mats on the bank can also be dangerous. Therefore, don't rely on the fact that water outside of a visible green area is automatically safe.

Possible clues are:

An normal-looking water surface is not a guarantee. Before swimming, check the current information from the relevant municipality or federal state. If you are unsure, keep your dog on a lead and out of the water.

Depending on the toxin, the symptoms can appear very quickly. Possible warning signs include:

If you suspect exposure, don't wait for several symptoms to come together. Cyanotoxin poisoning can develop dramatically in a short period of time.

Get your dog out of the water immediately and prevent him from licking his fur. Wear gloves if visible deposits are present. Rinse the fur and paws thoroughly with clean tap water without letting the dog drink the rinse water.

Call the nearest veterinary practice or veterinary hospital immediately and report the possible cyanobacteria exposure. Provide location, time, symptoms and estimated amount of water. If possible without delay, take photos of the water source and warning signs. Then drive off straight away.

Do not induce vomiting yourself or give home remedies. There is no safe at-home procedure that can replace emergency veterinary treatment.

Pay attention to swimming bans and local warnings. Do not let your dog loose on the shore in unknown or suspicious waters. When going on excursions, take enough fresh drinking water and a bowl with you so that he doesn't have to drink from a lake, pond or puddle.

Rinse your dog after swimming in natural water, especially if the water was cloudy or there was visible debris on the shore. Also check sticks and toys that may have come into contact with contaminated water or shore mats.

Cyanobacteria can produce liver and neurotoxins. Since the toxicity cannot be clearly identified by its appearance, the following applies to suspicious water: do not let your dog drink or swim, and prevent licking of contaminated fur. After possible contact, rinse fur and seek veterinary advice immediately - if symptoms occur, go straight to the clinic.