Dr. Webster’s BLOG

Cyanobacteria in Freshwater


Florida is known for its picturesque beaches, stunning lakes and warm climate. This offers an attractive environment for both you and your furry companions. However, this paradise isn’t without its challenges, and one of the growing concerns here in the Sunshine State is the threat posed by cyanobacteria to your pets. Cyanobacteria, often referred to as blue-green algae, can be harmful to both humans and animals. In this article, we will delve into the dangers of cyanobacteria for pets in Florida and how you can protect your pets if they love playing in the water.

What is Cyanobacteria?

Cyanobacteria are a group of microorganisms that thrive in water bodies, particularly in warm and nutrient-rich environments. They can be found in freshwater lakes, ponds, rivers, and even some saltwater environments. For the purposes of this article, we’ll focus on freshwater. The state of Florida regularly monitors these in larger bodies of water like Lake Okeechobee, but it would be impossible to monitor each pond or lake in the Sunshine State.

Cyanobacteria and Harmful Algal Blooms (HABs)

Cyanobacteria can form dense populations known as Harmful Algal Blooms (HABs). These blooms can give the water a green, blue-green, or reddish appearance and often produce toxins, including microcystins and anatoxins, that can be hazardous to both pets and humans.

While some forms of cyanobacteria are harmless, others produce toxins that can be dangerous when ingested or exposed to the skin. Unfortunately, it is not possible to identify a toxic algae bloom just by looking at it. If your pet enjoys swimming of frolicking in your backyard or neighborhood pond, it is important to visually inspect the water- and use extreme caution (or simply avoid) any water that has a green/blue or reddish appearance.

Risks to Pets

  1. Ingestion: Dogs are especially at risk because they are more likely to drink water from lakes, rivers, and ponds. When cyanobacteria are present in these water bodies, dogs can ingest the toxins while swimming or playing.


  1. Skin Contact: Cyanobacteria toxins can also cause skin irritation. Dogs that swim in or come into contact with water contaminated by cyanobacteria may experience rashes, hives, or other skin issues.


  1. Inhalation: In some cases, aerosolized toxins from cyanobacteria can be inhaled, leading to respiratory problems in pets.

Symptoms of Cyanobacteria Poisoning in Pets

Recognizing the signs of cyanobacteria poisoning in pets is crucial for prompt treatment. Symptoms may include:

  • Vomiting
  • Diarrhea
  • Lethargy
  • Stumbling or loss of coordination
  • Tremors or seizures
  • Excessive drooling
  • Difficulty breathing
  • Liver failure (in severe cases)

If you notice any of the symptoms after your pet plays in the water, contact your veterinarian immediately.

Tips to protect your pet:

  1. Avoid Contaminated Water: The most effective way to protect your pets is to avoid water bodies with visible signs of cyanobacteria blooms. As mentioned earlier, the state only routinely monitors large bodies of water. To learn more about the state’s testing see their website. Some sites have been tested in our area, and the latest data can be found on the site.


  1. Keep Your Dog on a Leash: When near water bodies, keep your dog on a leash to prevent them from drinking or swimming in potentially contaminated water.


  1. Rinse After Water Activities: After any water activity, rinse your pet thoroughly with clean, fresh water to remove any potential toxins from their fur and skin.


  1. Provide Fresh Water: Always carry clean, fresh water for your pet to drink during outdoor activities, so they are less tempted to drink from natural water sources.

While our state’s natural resources are excellent, it’s essential for pet owners to be aware of the potential threat posed by cyanobacteria in our area’s ponds and lakes. By taking precautions, staying informed, and being proactive, you can ensure the safety and well-being of your beloved pets while enjoying the great outdoors in the Sunshine State. Always remember that when in doubt, it’s better to be cautious and protect your furry friends from potential harm.