Many dogs love to swim in the ocean, lakes, ponds, and rivers during the summer, but not all water is safe. Blue-green algae, which can bloom during hot weather, can be extremely toxic to dogs. While blue-green algae are the most notorious for producing dangerous toxins, most true green algae and aquatic plants (like duckweed) are not toxic to dogs. However, it is difficult to distinguish toxic from non-toxic blooms visually, so all algal blooms should be treated as potentially dangerous.
Blue green algae often looks like green scum or pea soup on the surface of the water. Ingesting even a small amount while swimming or licking their fur afterward can cause rapid and severe illness. Symptoms may include vomiting, diarrhea, lethargy, seizures, and even death in extreme cases.
To protect your dog, avoid letting them swim in or drink from water that looks discolored, has a strange smell, or is stagnant. Bring fresh water with you to keep your dog hydrated and rinse it off after any swim, even in clean water
Stay alert for local warnings about algae blooms in recreational areas. Checking water safety before your dog jumps in can make the difference between a fun day and a tragedy.