Experts Warn: Blue-Green Algae Potentially Lethal to Dogs

Harmful algal blooms that can be found in New York State’s fresh water are known to be toxic to dogs, and, in some cases, even fatal.


If you walk your pooch near a lake or occasionally let them cool off by swimming in it, you might want to take necessary precautions. Namely, a particular species of freshwater algae can cause a myriad of health issues to both humans and their furry best friends- and, when it comes to canines, even death.


The problematic algae are the blue-green one, also known as cyanobacteria. These harmful algal blooms produce a variety of toxic substances, including neurotoxins and hepatotoxins, which, once dogs come in contact with it, can cause neurological or liver damage. In cases where the animal wasn’t brought to a vet on time, the toxins turned out to be fatal. While the toxins can affect your pet even if they merely come into contact with their skin, the far worse scenario if they ingest them by drinking contaminated lake water.


How to Recognize Blue-Green Algae Poisoning


Hepatotoxin exposure symptoms


  • repeated vomiting (green liquid)
  • diarrhea or tarry (bloody) stool
  • loss of appetite, anorexia
  • jaundice (yellowing of eye whites, gums)
  • abdominal swelling may be tender to the touch
  • cyanosis (bluish coloration) of skin
  • dark urine or reduced/ no urine output


Neurotoxin exposure symptoms


  • stumbling, seizures, convulsions, paralysis
  • excessive salivation/drooling
  • disorientation, inactivity or depression
  • elevated heart rate, difficulty breathing


How to Prevent Blue-Green Algae Poisoning


The safest way is to keep your pet on a leash at all times, particularly if your daily walk routes are in areas near lakes or other bodies of freshwater. Make sure to prevent your pet from going to the water, whether to drink, swim or just explore, especially if you notice that the water is foamy or pea soup-like. You should also steer clear if you see scums or floating mats (any color, not just blue-green in the water or on the shore, as dogs tend to be attracted by the scent of it.


While the situation is particularly dire in New York State, harmful algal blooms can be found worldwide, so don’t let your furbaby sniff around slimy lakes- wherever you live.

Angela Vuckovic
Angela Vuckovic

A proud mama to seven dogs and ten cats, Angela spends her days writing for her fellow pet parents and pampering her furballs, all of whom are rescues. When she's not gushing over her adorable cats or playing with her dogs, she can be found curled up with a good fantasy book.

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