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Blue Green Algae - What Exactly Is It?

Blue Green Algae - What Exactly Is It?
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You may have seen reports of blue-green algae contamination in ponds and lakes during this hot spell of weather.

Here is an update on what you need to know about this potentially fatal toxin.

What is blue-green algae?

Blue-green algae (cyanobacteria) are microscopic bacteria found in freshwater lakes, streams, ponds and brackish water.

They can produce toxins that affect people, livestock and pets that swim in or drink from the contaminated water.

What does blue-green algae look like?

The bacteria are not visible to the naked eye unless they clump together to form “blooms”, which can give the water a “pea soup” appearance. Sometimes it can appear like foam or scum at the edge of the water.

It is most common in non-flowing fresh water, such as lakes and ponds, during periods of hot weather, although it can also occur at other times of the year.

Why is blue-green algae dangerous to dogs?

Not all forms of cyanobacteria are toxic, but it is impossible to tell without testing, so all algal blooms should be considered potentially dangerous.

The bacteria can produce different types of toxins, which can affect the liver or nervous system.

Exposure to toxic blue-green algae is often fatal, potentially within as little as 15-60 minutes.

What are the symptoms of blue-green algae poisoning?

The symptoms depend on the type of toxin produced, but may include:

  • Vomiting
  • Diarrhoea
  • Seizures / fitting
  • Weakness / collapse / unconsciousness
  • Disorientation/confusion
  • Salivation / drooling
  • Breathing difficulties

There is no antidote for the toxins produced by the bacteria. Immediate veterinary attention is imperative.

How can I protect my dog from blue-green algae?

Keep your dog away from lakes and ponds that you know or suspect may contain blue-green algae.

Take note of signs warning of the algae during dog walks and follow the information given.

Who else can be affected by blue-green algae?

Blue-green algae can be toxic to dogs, cats, livestock, birds, fish and people (especially children).

If you think you have spotted blue-green algae in water and cannot see any signage, report it to the Environment Agency  who can investigate.

If you have any further questions about blue-green algae or any other aspect of your pet’s health, please do not hesitate to contact us for advice.