06/10/2026
Wellness Wednesday: Harmful Algal Blooms 🦠
Harmful algal bloom (HABs) season has begun! HABs can cause serious illness or death in pets that ingest water or mats containing high concentrations of cyanotoxins. Dogs can become extremely ill, and even die, within minutes to hours of exposure.
When in doubt, stay out! If you find thick, pea-green or blue-green foam, thick green or brownish-red mats, or bright green clumps suspended in the water in any body of water—especially in shallow, marshy areas where cyanobacteria blooms can form—do not let your pet drink or swim in the water.
Symptoms of exposure to a harmful algal bloom can include:
Weakness or collapse
Nausea, vomiting
Excessive drooling
Weakness, fatigue, stumbling
Abdominal pain
Diarrhea
Difficulty breathing
Shaking, trembling
Seizure like activity—tremors, rigidity, paralysis
Liver failure
The Oregon Health Authority has a live map on their website that updates what locations are marked as safe and unsafe from cytotoxins. Not all Oregon waterways are monitored for cyanobacteria blooms, so it's important to know what to watch for!
