Stay Out of the Water

Something deadly to your pet may be lurking in the water this summer…and it isn’t that great for humans either.

Blue-green algae is cyanobacteria that infests freshwater lakes, streams, and ponds in the summer months. Unlike other algae, it is toxic and can be fatal. It thrives where there is heat, low water flow, and high amounts of nutrients like nitrogen and phosphorus.

Pets can be exposed to blue-green algae by ingesting it, through their skin, and even just by inhaling it. Dogs are the most common victims of blue-green algae poisoning, but livestock, birds, and cats are at risk too.

Blue-green algae sometimes smells bad and looks like spilled green paint or floating scum. To be on the safe side, keep your pet away from any water that looks greenish.

Symptoms of blue-green algae poisoning in pets include vomiting, diarrhea, difficulty breathing, muscle tremors or rigidity, seizures, coma and excessive drooling. There is no antidote for the toxins from blue-green algae. Death may occur within hours of exposure, even with treatment. If the pet has been exposed, rinse it with fresh water and seek immediate veterinary help.


Blue-Green Algae Information Bulletin. Available from:

Blue-Green Algae. Available from:

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